blob: 4d2b82e610e2a48f429a700f0529d6dc5942700a [file] [log] [blame]
Arjan van de Venf71d20e2006-06-28 04:26:45 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 Copyright (C) 2002 Richard Henderson
Rusty Russell51f3d0f2010-08-05 12:59:13 -06003 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18*/
Paul Gortmaker9984de12011-05-23 14:51:41 -040019#include <linux/export.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/moduleloader.h>
Steven Rostedt (Red Hat)af658dc2015-04-29 14:36:05 -040021#include <linux/trace_events.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/init.h>
Alexey Dobriyanae84e322007-05-08 00:28:38 -070023#include <linux/kallsyms.h>
Kees Cook34e11692012-10-16 07:31:07 +103024#include <linux/file.h>
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +040025#include <linux/fs.h>
Roland McGrath6d760132007-10-16 23:26:40 -070026#include <linux/sysfs.h>
Randy Dunlap9f158332005-09-13 01:25:16 -070027#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/slab.h>
29#include <linux/vmalloc.h>
30#include <linux/elf.h>
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +040031#include <linux/proc_fs.h>
Kees Cook2e72d512012-10-16 07:32:07 +103032#include <linux/security.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/seq_file.h>
34#include <linux/syscalls.h>
35#include <linux/fcntl.h>
36#include <linux/rcupdate.h>
Randy.Dunlapc59ede72006-01-11 12:17:46 -080037#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038#include <linux/cpu.h>
39#include <linux/moduleparam.h>
40#include <linux/errno.h>
41#include <linux/err.h>
42#include <linux/vermagic.h>
43#include <linux/notifier.h>
Al Virof6a57032006-10-18 01:47:25 -040044#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045#include <linux/device.h>
Matt Domschc988d2b2005-06-23 22:05:15 -070046#include <linux/string.h>
Arjan van de Ven97d1f152006-03-23 03:00:24 -080047#include <linux/mutex.h>
Andi Kleend72b3752008-08-30 10:09:00 +020048#include <linux/rculist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070049#include <asm/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070050#include <asm/cacheflush.h>
Bernd Schmidteb8cdec2009-09-21 17:03:57 -070051#include <asm/mmu_context.h>
Sam Ravnborgb817f6f2006-06-09 21:53:55 +020052#include <linux/license.h>
Christoph Lameter6d762392008-02-08 04:18:42 -080053#include <asm/sections.h>
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -040054#include <linux/tracepoint.h>
Steven Rostedt90d595f2008-08-14 15:45:09 -040055#include <linux/ftrace.h>
Arjan van de Ven22a9d642009-01-07 08:45:46 -080056#include <linux/async.h>
Tejun Heofbf59bc2009-02-20 16:29:08 +090057#include <linux/percpu.h>
Catalin Marinas4f2294b2009-06-11 13:23:20 +010058#include <linux/kmemleak.h>
Jason Baronbf5438fc2010-09-17 11:09:00 -040059#include <linux/jump_label.h>
matthieu castet84e1c6b2010-11-16 22:35:16 +010060#include <linux/pfn.h>
Alessio Igor Bogani403ed272011-04-20 11:10:52 +020061#include <linux/bsearch.h>
Rusty Russell2f3238a2012-10-22 18:09:41 +103062#include <uapi/linux/module.h>
Rusty Russell106a4ee2012-09-26 10:09:40 +010063#include "module-internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
Li Zefan7ead8b82009-08-17 16:56:28 +080065#define CREATE_TRACE_POINTS
66#include <trace/events/module.h>
67
Linus Torvalds1da177e2005-04-16 15:20:36 -070068#ifndef ARCH_SHF_SMALL
69#define ARCH_SHF_SMALL 0
70#endif
71
matthieu castet84e1c6b2010-11-16 22:35:16 +010072/*
73 * Modules' sections will be aligned on page boundaries
74 * to ensure complete separation of code and data, but
75 * only when CONFIG_DEBUG_SET_MODULE_RONX=y
76 */
77#ifdef CONFIG_DEBUG_SET_MODULE_RONX
78# define debug_align(X) ALIGN(X, PAGE_SIZE)
79#else
80# define debug_align(X) (X)
81#endif
82
83/*
84 * Given BASE and SIZE this macro calculates the number of pages the
85 * memory regions occupies
86 */
87#define MOD_NUMBER_OF_PAGES(BASE, SIZE) (((SIZE) > 0) ? \
88 (PFN_DOWN((unsigned long)(BASE) + (SIZE) - 1) - \
89 PFN_DOWN((unsigned long)BASE) + 1) \
90 : (0UL))
91
Linus Torvalds1da177e2005-04-16 15:20:36 -070092/* If this is set, the section belongs in the init part of the module */
93#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
94
Rusty Russell75676502010-06-05 11:17:36 -060095/*
96 * Mutex protects:
97 * 1) List of modules (also safely readable with preempt_disable),
98 * 2) module_use links,
99 * 3) module_addr_min/module_addr_max.
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030100 * (delete and add uses RCU list operations). */
Tim Abbottc6b37802008-12-05 19:03:59 -0500101DEFINE_MUTEX(module_mutex);
102EXPORT_SYMBOL_GPL(module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103static LIST_HEAD(modules);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930104
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930105#ifdef CONFIG_MODULES_TREE_LOOKUP
106
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930107/*
108 * Use a latched RB-tree for __module_address(); this allows us to use
109 * RCU-sched lookups of the address from any context.
110 *
111 * Because modules have two address ranges: init and core, we need two
112 * latch_tree_nodes entries. Therefore we need the back-pointer from
113 * mod_tree_node.
114 *
115 * Because init ranges are short lived we mark them unlikely and have placed
116 * them outside the critical cacheline in struct module.
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930117 *
118 * This is conditional on PERF_EVENTS || TRACING because those can really hit
119 * __module_address() hard by doing a lot of stack unwinding; potentially from
120 * NMI context.
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930121 */
122
123static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
124{
125 struct mod_tree_node *mtn = container_of(n, struct mod_tree_node, node);
126 struct module *mod = mtn->mod;
127
128 if (unlikely(mtn == &mod->mtn_init))
129 return (unsigned long)mod->module_init;
130
131 return (unsigned long)mod->module_core;
132}
133
134static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
135{
136 struct mod_tree_node *mtn = container_of(n, struct mod_tree_node, node);
137 struct module *mod = mtn->mod;
138
139 if (unlikely(mtn == &mod->mtn_init))
140 return (unsigned long)mod->init_size;
141
142 return (unsigned long)mod->core_size;
143}
144
145static __always_inline bool
146mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b)
147{
148 return __mod_tree_val(a) < __mod_tree_val(b);
149}
150
151static __always_inline int
152mod_tree_comp(void *key, struct latch_tree_node *n)
153{
154 unsigned long val = (unsigned long)key;
155 unsigned long start, end;
156
157 start = __mod_tree_val(n);
158 if (val < start)
159 return -1;
160
161 end = start + __mod_tree_size(n);
162 if (val >= end)
163 return 1;
164
165 return 0;
166}
167
168static const struct latch_tree_ops mod_tree_ops = {
169 .less = mod_tree_less,
170 .comp = mod_tree_comp,
171};
172
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930173static struct mod_tree_root {
174 struct latch_tree_root root;
175 unsigned long addr_min;
176 unsigned long addr_max;
177} mod_tree __cacheline_aligned = {
178 .addr_min = -1UL,
179};
180
181#define module_addr_min mod_tree.addr_min
182#define module_addr_max mod_tree.addr_max
183
184static noinline void __mod_tree_insert(struct mod_tree_node *node)
185{
186 latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);
187}
188
189static void __mod_tree_remove(struct mod_tree_node *node)
190{
191 latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);
192}
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930193
194/*
195 * These modifications: insert, remove_init and remove; are serialized by the
196 * module_mutex.
197 */
198static void mod_tree_insert(struct module *mod)
199{
200 mod->mtn_core.mod = mod;
201 mod->mtn_init.mod = mod;
202
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930203 __mod_tree_insert(&mod->mtn_core);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930204 if (mod->init_size)
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930205 __mod_tree_insert(&mod->mtn_init);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930206}
207
208static void mod_tree_remove_init(struct module *mod)
209{
210 if (mod->init_size)
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930211 __mod_tree_remove(&mod->mtn_init);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930212}
213
214static void mod_tree_remove(struct module *mod)
215{
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930216 __mod_tree_remove(&mod->mtn_core);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930217 mod_tree_remove_init(mod);
218}
219
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930220static struct module *mod_find(unsigned long addr)
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930221{
222 struct latch_tree_node *ltn;
223
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930224 ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930225 if (!ltn)
226 return NULL;
227
228 return container_of(ltn, struct mod_tree_node, node)->mod;
229}
230
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930231#else /* MODULES_TREE_LOOKUP */
232
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930233static unsigned long module_addr_min = -1UL, module_addr_max = 0;
234
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930235static void mod_tree_insert(struct module *mod) { }
236static void mod_tree_remove_init(struct module *mod) { }
237static void mod_tree_remove(struct module *mod) { }
238
239static struct module *mod_find(unsigned long addr)
240{
241 struct module *mod;
242
243 list_for_each_entry_rcu(mod, &modules, list) {
244 if (within_module(addr, mod))
245 return mod;
246 }
247
248 return NULL;
249}
250
251#endif /* MODULES_TREE_LOOKUP */
252
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930253/*
254 * Bounds of module text, for speeding up __module_address.
255 * Protected by module_mutex.
256 */
257static void __mod_update_bounds(void *base, unsigned int size)
258{
259 unsigned long min = (unsigned long)base;
260 unsigned long max = min + size;
261
262 if (min < module_addr_min)
263 module_addr_min = min;
264 if (max > module_addr_max)
265 module_addr_max = max;
266}
267
268static void mod_update_bounds(struct module *mod)
269{
270 __mod_update_bounds(mod->module_core, mod->core_size);
271 if (mod->init_size)
272 __mod_update_bounds(mod->module_init, mod->init_size);
273}
274
Jason Wessel67fc4e02010-05-20 21:04:21 -0500275#ifdef CONFIG_KGDB_KDB
276struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
277#endif /* CONFIG_KGDB_KDB */
278
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930279static void module_assert_mutex(void)
Rusty Russell106a4ee2012-09-26 10:09:40 +0100280{
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930281 lockdep_assert_held(&module_mutex);
Rusty Russell106a4ee2012-09-26 10:09:40 +0100282}
283
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930284static void module_assert_mutex_or_preempt(void)
285{
286#ifdef CONFIG_LOCKDEP
287 if (unlikely(!debug_locks))
288 return;
Rusty Russell106a4ee2012-09-26 10:09:40 +0100289
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930290 WARN_ON(!rcu_read_lock_sched_held() &&
291 !lockdep_is_held(&module_mutex));
292#endif
293}
294
Luis R. Rodriguez6727bb92015-05-27 11:09:39 +0930295static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);
296#ifndef CONFIG_MODULE_SIG_FORCE
Rusty Russell106a4ee2012-09-26 10:09:40 +0100297module_param(sig_enforce, bool_enable_only, 0644);
298#endif /* !CONFIG_MODULE_SIG_FORCE */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299
Stephen Rothwell19e45292009-04-14 17:27:18 +1000300/* Block module loading/unloading? */
301int modules_disabled = 0;
Dave Young02608be2012-02-01 10:33:14 +0800302core_param(nomodule, modules_disabled, bint, 0);
Stephen Rothwell19e45292009-04-14 17:27:18 +1000303
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500304/* Waiting for a module to finish initializing? */
305static DECLARE_WAIT_QUEUE_HEAD(module_wq);
306
Alan Sterne041c682006-03-27 01:16:30 -0800307static BLOCKING_NOTIFIER_HEAD(module_notify_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308
Ionut Alexa6da0b562014-11-10 09:31:29 +1030309int register_module_notifier(struct notifier_block *nb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310{
Alan Sterne041c682006-03-27 01:16:30 -0800311 return blocking_notifier_chain_register(&module_notify_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312}
313EXPORT_SYMBOL(register_module_notifier);
314
Ionut Alexa6da0b562014-11-10 09:31:29 +1030315int unregister_module_notifier(struct notifier_block *nb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316{
Alan Sterne041c682006-03-27 01:16:30 -0800317 return blocking_notifier_chain_unregister(&module_notify_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318}
319EXPORT_SYMBOL(unregister_module_notifier);
320
Rusty Russelleded41c2010-08-05 12:59:07 -0600321struct load_info {
322 Elf_Ehdr *hdr;
323 unsigned long len;
324 Elf_Shdr *sechdrs;
Rusty Russell6526c532010-08-05 12:59:10 -0600325 char *secstrings, *strtab;
Rusty Russelld9131882010-08-05 12:59:08 -0600326 unsigned long symoffs, stroffs;
Rusty Russell811d66a2010-08-05 12:59:12 -0600327 struct _ddebug *debug;
328 unsigned int num_debug;
Rusty Russell106a4ee2012-09-26 10:09:40 +0100329 bool sig_ok;
Rusty Russelleded41c2010-08-05 12:59:07 -0600330 struct {
331 unsigned int sym, str, mod, vers, info, pcpu;
332 } index;
333};
334
Matti Linnanvuori9a4b9702007-11-08 08:37:38 -0800335/* We require a truly strong try_module_get(): 0 means failure due to
336 ongoing or failed initialization etc. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337static inline int strong_try_module_get(struct module *mod)
338{
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030339 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 if (mod && mod->state == MODULE_STATE_COMING)
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500341 return -EBUSY;
342 if (try_module_get(mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 return 0;
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500344 else
345 return -ENOENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346}
347
Rusty Russell373d4d02013-01-21 17:17:39 +1030348static inline void add_taint_module(struct module *mod, unsigned flag,
349 enum lockdep_ok lockdep_ok)
Florin Malitafa3ba2e82006-10-11 01:21:48 -0700350{
Rusty Russell373d4d02013-01-21 17:17:39 +1030351 add_taint(flag, lockdep_ok);
Andi Kleen25ddbb12008-10-15 22:01:41 -0700352 mod->taints |= (1U << flag);
Florin Malitafa3ba2e82006-10-11 01:21:48 -0700353}
354
Robert P. J. Day02a3e592007-05-09 07:26:28 +0200355/*
356 * A thread that wants to hold a reference to a module only while it
357 * is running can call this to safely exit. nfsd and lockd use this.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358 */
359void __module_put_and_exit(struct module *mod, long code)
360{
361 module_put(mod);
362 do_exit(code);
363}
364EXPORT_SYMBOL(__module_put_and_exit);
Daniel Walker22a8bde2007-10-18 03:06:07 -0700365
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366/* Find a module section: 0 means not found. */
Rusty Russell49668682010-08-05 12:59:10 -0600367static unsigned int find_sec(const struct load_info *info, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368{
369 unsigned int i;
370
Rusty Russell49668682010-08-05 12:59:10 -0600371 for (i = 1; i < info->hdr->e_shnum; i++) {
372 Elf_Shdr *shdr = &info->sechdrs[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373 /* Alloc bit cleared means "ignore it." */
Rusty Russell49668682010-08-05 12:59:10 -0600374 if ((shdr->sh_flags & SHF_ALLOC)
375 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 return i;
Rusty Russell49668682010-08-05 12:59:10 -0600377 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 return 0;
379}
380
Rusty Russell5e458cc2008-10-22 10:00:13 -0500381/* Find a module section, or NULL. */
Rusty Russell49668682010-08-05 12:59:10 -0600382static void *section_addr(const struct load_info *info, const char *name)
Rusty Russell5e458cc2008-10-22 10:00:13 -0500383{
384 /* Section 0 has sh_addr 0. */
Rusty Russell49668682010-08-05 12:59:10 -0600385 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
Rusty Russell5e458cc2008-10-22 10:00:13 -0500386}
387
388/* Find a module section, or NULL. Fill in number of "objects" in section. */
Rusty Russell49668682010-08-05 12:59:10 -0600389static void *section_objs(const struct load_info *info,
Rusty Russell5e458cc2008-10-22 10:00:13 -0500390 const char *name,
391 size_t object_size,
392 unsigned int *num)
393{
Rusty Russell49668682010-08-05 12:59:10 -0600394 unsigned int sec = find_sec(info, name);
Rusty Russell5e458cc2008-10-22 10:00:13 -0500395
396 /* Section 0 has sh_addr 0 and sh_size 0. */
Rusty Russell49668682010-08-05 12:59:10 -0600397 *num = info->sechdrs[sec].sh_size / object_size;
398 return (void *)info->sechdrs[sec].sh_addr;
Rusty Russell5e458cc2008-10-22 10:00:13 -0500399}
400
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401/* Provided by the linker */
402extern const struct kernel_symbol __start___ksymtab[];
403extern const struct kernel_symbol __stop___ksymtab[];
404extern const struct kernel_symbol __start___ksymtab_gpl[];
405extern const struct kernel_symbol __stop___ksymtab_gpl[];
Greg Kroah-Hartman9f28bb72006-03-20 13:17:13 -0800406extern const struct kernel_symbol __start___ksymtab_gpl_future[];
407extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408extern const unsigned long __start___kcrctab[];
409extern const unsigned long __start___kcrctab_gpl[];
Greg Kroah-Hartman9f28bb72006-03-20 13:17:13 -0800410extern const unsigned long __start___kcrctab_gpl_future[];
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500411#ifdef CONFIG_UNUSED_SYMBOLS
412extern const struct kernel_symbol __start___ksymtab_unused[];
413extern const struct kernel_symbol __stop___ksymtab_unused[];
414extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
415extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700416extern const unsigned long __start___kcrctab_unused[];
417extern const unsigned long __start___kcrctab_unused_gpl[];
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500418#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419
420#ifndef CONFIG_MODVERSIONS
421#define symversion(base, idx) NULL
422#else
Andrew Mortonf83ca9f2006-03-28 01:56:20 -0800423#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424#endif
425
Rusty Russelldafd0942008-07-22 19:24:25 -0500426static bool each_symbol_in_section(const struct symsearch *arr,
427 unsigned int arrsize,
428 struct module *owner,
429 bool (*fn)(const struct symsearch *syms,
430 struct module *owner,
Rusty Russellde4d8d52011-04-19 21:49:58 +0200431 void *data),
Rusty Russelldafd0942008-07-22 19:24:25 -0500432 void *data)
Sam Ravnborg3fd68052006-02-08 21:16:45 +0100433{
Rusty Russellde4d8d52011-04-19 21:49:58 +0200434 unsigned int j;
Rusty Russelldafd0942008-07-22 19:24:25 -0500435
436 for (j = 0; j < arrsize; j++) {
Rusty Russellde4d8d52011-04-19 21:49:58 +0200437 if (fn(&arr[j], owner, data))
438 return true;
Rusty Russelldafd0942008-07-22 19:24:25 -0500439 }
440
441 return false;
Sam Ravnborg3fd68052006-02-08 21:16:45 +0100442}
443
Rusty Russelldafd0942008-07-22 19:24:25 -0500444/* Returns true as soon as fn returns true, otherwise false. */
Rusty Russellde4d8d52011-04-19 21:49:58 +0200445bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
446 struct module *owner,
447 void *data),
448 void *data)
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700449{
Rusty Russelldafd0942008-07-22 19:24:25 -0500450 struct module *mod;
Linus Torvalds44032e62010-08-05 12:59:05 -0600451 static const struct symsearch arr[] = {
Rusty Russelldafd0942008-07-22 19:24:25 -0500452 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
453 NOT_GPL_ONLY, false },
454 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
455 __start___kcrctab_gpl,
456 GPL_ONLY, false },
457 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
458 __start___kcrctab_gpl_future,
459 WILL_BE_GPL_ONLY, false },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500460#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500461 { __start___ksymtab_unused, __stop___ksymtab_unused,
462 __start___kcrctab_unused,
463 NOT_GPL_ONLY, true },
464 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
465 __start___kcrctab_unused_gpl,
466 GPL_ONLY, true },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500467#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500468 };
469
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930470 module_assert_mutex_or_preempt();
471
Rusty Russelldafd0942008-07-22 19:24:25 -0500472 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
473 return true;
474
Andi Kleend72b3752008-08-30 10:09:00 +0200475 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russelldafd0942008-07-22 19:24:25 -0500476 struct symsearch arr[] = {
477 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
478 NOT_GPL_ONLY, false },
479 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
480 mod->gpl_crcs,
481 GPL_ONLY, false },
482 { mod->gpl_future_syms,
483 mod->gpl_future_syms + mod->num_gpl_future_syms,
484 mod->gpl_future_crcs,
485 WILL_BE_GPL_ONLY, false },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500486#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500487 { mod->unused_syms,
488 mod->unused_syms + mod->num_unused_syms,
489 mod->unused_crcs,
490 NOT_GPL_ONLY, true },
491 { mod->unused_gpl_syms,
492 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
493 mod->unused_gpl_crcs,
494 GPL_ONLY, true },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500495#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500496 };
497
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030498 if (mod->state == MODULE_STATE_UNFORMED)
499 continue;
500
Rusty Russelldafd0942008-07-22 19:24:25 -0500501 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
502 return true;
503 }
504 return false;
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700505}
Rusty Russellde4d8d52011-04-19 21:49:58 +0200506EXPORT_SYMBOL_GPL(each_symbol_section);
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700507
Rusty Russelldafd0942008-07-22 19:24:25 -0500508struct find_symbol_arg {
509 /* Input */
510 const char *name;
511 bool gplok;
512 bool warn;
513
514 /* Output */
515 struct module *owner;
516 const unsigned long *crc;
Tim Abbott414fd312008-12-05 19:03:56 -0500517 const struct kernel_symbol *sym;
Rusty Russelldafd0942008-07-22 19:24:25 -0500518};
519
Rusty Russellde4d8d52011-04-19 21:49:58 +0200520static bool check_symbol(const struct symsearch *syms,
521 struct module *owner,
522 unsigned int symnum, void *data)
Rusty Russellad9546c2008-05-01 21:14:59 -0500523{
Rusty Russelldafd0942008-07-22 19:24:25 -0500524 struct find_symbol_arg *fsa = data;
525
Rusty Russelldafd0942008-07-22 19:24:25 -0500526 if (!fsa->gplok) {
527 if (syms->licence == GPL_ONLY)
528 return false;
529 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800530 pr_warn("Symbol %s is being used by a non-GPL module, "
531 "which will not be allowed in the future\n",
532 fsa->name);
Rusty Russelldafd0942008-07-22 19:24:25 -0500533 }
534 }
535
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500536#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500537 if (syms->unused && fsa->warn) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800538 pr_warn("Symbol %s is marked as UNUSED, however this module is "
539 "using it.\n", fsa->name);
540 pr_warn("This symbol will go away in the future.\n");
Yannick Guerrini7b63c3a2015-03-24 12:31:40 +1030541 pr_warn("Please evaluate if this is the right api to use and "
542 "if it really is, submit a report to the linux kernel "
543 "mailing list together with submitting your code for "
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800544 "inclusion.\n");
Rusty Russellad9546c2008-05-01 21:14:59 -0500545 }
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500546#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500547
548 fsa->owner = owner;
549 fsa->crc = symversion(syms->crcs, symnum);
Tim Abbott414fd312008-12-05 19:03:56 -0500550 fsa->sym = &syms->start[symnum];
Rusty Russellad9546c2008-05-01 21:14:59 -0500551 return true;
552}
553
Alessio Igor Bogani403ed272011-04-20 11:10:52 +0200554static int cmp_name(const void *va, const void *vb)
555{
556 const char *a;
557 const struct kernel_symbol *b;
558 a = va; b = vb;
559 return strcmp(a, b->name);
560}
561
Rusty Russellde4d8d52011-04-19 21:49:58 +0200562static bool find_symbol_in_section(const struct symsearch *syms,
563 struct module *owner,
564 void *data)
565{
566 struct find_symbol_arg *fsa = data;
Alessio Igor Bogani403ed272011-04-20 11:10:52 +0200567 struct kernel_symbol *sym;
Rusty Russellde4d8d52011-04-19 21:49:58 +0200568
Alessio Igor Bogani403ed272011-04-20 11:10:52 +0200569 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
570 sizeof(struct kernel_symbol), cmp_name);
571
572 if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
573 return true;
574
Rusty Russellde4d8d52011-04-19 21:49:58 +0200575 return false;
576}
577
Tim Abbott414fd312008-12-05 19:03:56 -0500578/* Find a symbol and return it, along with, (optional) crc and
Rusty Russell75676502010-06-05 11:17:36 -0600579 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
Tim Abbottc6b37802008-12-05 19:03:59 -0500580const struct kernel_symbol *find_symbol(const char *name,
581 struct module **owner,
582 const unsigned long **crc,
583 bool gplok,
584 bool warn)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585{
Rusty Russelldafd0942008-07-22 19:24:25 -0500586 struct find_symbol_arg fsa;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587
Rusty Russelldafd0942008-07-22 19:24:25 -0500588 fsa.name = name;
589 fsa.gplok = gplok;
590 fsa.warn = warn;
591
Rusty Russellde4d8d52011-04-19 21:49:58 +0200592 if (each_symbol_section(find_symbol_in_section, &fsa)) {
Rusty Russellad9546c2008-05-01 21:14:59 -0500593 if (owner)
Rusty Russelldafd0942008-07-22 19:24:25 -0500594 *owner = fsa.owner;
595 if (crc)
596 *crc = fsa.crc;
Tim Abbott414fd312008-12-05 19:03:56 -0500597 return fsa.sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 }
Rusty Russellad9546c2008-05-01 21:14:59 -0500599
Jim Cromie5e124162011-12-06 12:11:31 -0700600 pr_debug("Failed to find symbol %s\n", name);
Tim Abbott414fd312008-12-05 19:03:56 -0500601 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602}
Tim Abbottc6b37802008-12-05 19:03:59 -0500603EXPORT_SYMBOL_GPL(find_symbol);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605/* Search for module by name: must hold module_mutex. */
Mathias Krause4f6de4d2013-07-02 15:35:11 +0930606static struct module *find_module_all(const char *name, size_t len,
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030607 bool even_unformed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608{
609 struct module *mod;
610
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930611 module_assert_mutex();
612
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 list_for_each_entry(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030614 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
615 continue;
Mathias Krause4f6de4d2013-07-02 15:35:11 +0930616 if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 return mod;
618 }
619 return NULL;
620}
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030621
622struct module *find_module(const char *name)
623{
Mathias Krause4f6de4d2013-07-02 15:35:11 +0930624 return find_module_all(name, strlen(name), false);
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030625}
Tim Abbottc6b37802008-12-05 19:03:59 -0500626EXPORT_SYMBOL_GPL(find_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627
628#ifdef CONFIG_SMP
Tejun Heofbf59bc2009-02-20 16:29:08 +0900629
Tejun Heo259354d2010-03-10 18:56:10 +0900630static inline void __percpu *mod_percpu(struct module *mod)
Tejun Heofbf59bc2009-02-20 16:29:08 +0900631{
Tejun Heo259354d2010-03-10 18:56:10 +0900632 return mod->percpu;
633}
Tejun Heofbf59bc2009-02-20 16:29:08 +0900634
Rusty Russell9eb76d72013-07-03 10:06:29 +0930635static int percpu_modalloc(struct module *mod, struct load_info *info)
Tejun Heo259354d2010-03-10 18:56:10 +0900636{
Rusty Russell9eb76d72013-07-03 10:06:29 +0930637 Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
638 unsigned long align = pcpusec->sh_addralign;
639
640 if (!pcpusec->sh_size)
641 return 0;
642
Tejun Heofbf59bc2009-02-20 16:29:08 +0900643 if (align > PAGE_SIZE) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800644 pr_warn("%s: per-cpu alignment %li > %li\n",
645 mod->name, align, PAGE_SIZE);
Tejun Heofbf59bc2009-02-20 16:29:08 +0900646 align = PAGE_SIZE;
647 }
648
Rusty Russell9eb76d72013-07-03 10:06:29 +0930649 mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
Tejun Heo259354d2010-03-10 18:56:10 +0900650 if (!mod->percpu) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800651 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
652 mod->name, (unsigned long)pcpusec->sh_size);
Tejun Heo259354d2010-03-10 18:56:10 +0900653 return -ENOMEM;
654 }
Rusty Russell9eb76d72013-07-03 10:06:29 +0930655 mod->percpu_size = pcpusec->sh_size;
Tejun Heo259354d2010-03-10 18:56:10 +0900656 return 0;
Tejun Heofbf59bc2009-02-20 16:29:08 +0900657}
658
Tejun Heo259354d2010-03-10 18:56:10 +0900659static void percpu_modfree(struct module *mod)
Tejun Heofbf59bc2009-02-20 16:29:08 +0900660{
Tejun Heo259354d2010-03-10 18:56:10 +0900661 free_percpu(mod->percpu);
Tejun Heofbf59bc2009-02-20 16:29:08 +0900662}
663
Rusty Russell49668682010-08-05 12:59:10 -0600664static unsigned int find_pcpusec(struct load_info *info)
Tejun Heo6b588c12009-02-20 16:29:07 +0900665{
Rusty Russell49668682010-08-05 12:59:10 -0600666 return find_sec(info, ".data..percpu");
Tejun Heo6b588c12009-02-20 16:29:07 +0900667}
668
Tejun Heo259354d2010-03-10 18:56:10 +0900669static void percpu_modcopy(struct module *mod,
670 const void *from, unsigned long size)
Tejun Heo6b588c12009-02-20 16:29:07 +0900671{
672 int cpu;
673
674 for_each_possible_cpu(cpu)
Tejun Heo259354d2010-03-10 18:56:10 +0900675 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
Tejun Heo6b588c12009-02-20 16:29:07 +0900676}
677
Tejun Heo10fad5e2010-03-10 18:57:54 +0900678/**
679 * is_module_percpu_address - test whether address is from module static percpu
680 * @addr: address to test
681 *
682 * Test whether @addr belongs to module static percpu area.
683 *
684 * RETURNS:
685 * %true if @addr is from module static percpu area
686 */
687bool is_module_percpu_address(unsigned long addr)
688{
689 struct module *mod;
690 unsigned int cpu;
691
692 preempt_disable();
693
694 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030695 if (mod->state == MODULE_STATE_UNFORMED)
696 continue;
Tejun Heo10fad5e2010-03-10 18:57:54 +0900697 if (!mod->percpu_size)
698 continue;
699 for_each_possible_cpu(cpu) {
700 void *start = per_cpu_ptr(mod->percpu, cpu);
701
702 if ((void *)addr >= start &&
703 (void *)addr < start + mod->percpu_size) {
704 preempt_enable();
705 return true;
706 }
707 }
708 }
709
710 preempt_enable();
711 return false;
Daniel Walker22a8bde2007-10-18 03:06:07 -0700712}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713
714#else /* ... !CONFIG_SMP */
Tejun Heo6b588c12009-02-20 16:29:07 +0900715
Tejun Heo259354d2010-03-10 18:56:10 +0900716static inline void __percpu *mod_percpu(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717{
718 return NULL;
719}
Rusty Russell9eb76d72013-07-03 10:06:29 +0930720static int percpu_modalloc(struct module *mod, struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721{
Rusty Russell9eb76d72013-07-03 10:06:29 +0930722 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
723 if (info->sechdrs[info->index.pcpu].sh_size != 0)
724 return -ENOMEM;
725 return 0;
Tejun Heo259354d2010-03-10 18:56:10 +0900726}
727static inline void percpu_modfree(struct module *mod)
728{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729}
Rusty Russell49668682010-08-05 12:59:10 -0600730static unsigned int find_pcpusec(struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731{
732 return 0;
733}
Tejun Heo259354d2010-03-10 18:56:10 +0900734static inline void percpu_modcopy(struct module *mod,
735 const void *from, unsigned long size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736{
737 /* pcpusec should be 0, and size of that section should be 0. */
738 BUG_ON(size != 0);
739}
Tejun Heo10fad5e2010-03-10 18:57:54 +0900740bool is_module_percpu_address(unsigned long addr)
741{
742 return false;
743}
Tejun Heo6b588c12009-02-20 16:29:07 +0900744
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745#endif /* CONFIG_SMP */
746
Matt Domschc988d2b2005-06-23 22:05:15 -0700747#define MODINFO_ATTR(field) \
748static void setup_modinfo_##field(struct module *mod, const char *s) \
749{ \
750 mod->field = kstrdup(s, GFP_KERNEL); \
751} \
752static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
Kay Sievers4befb022011-07-24 22:06:04 +0930753 struct module_kobject *mk, char *buffer) \
Matt Domschc988d2b2005-06-23 22:05:15 -0700754{ \
Chen Gangcc56ded2013-08-20 15:34:21 +0930755 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
Matt Domschc988d2b2005-06-23 22:05:15 -0700756} \
757static int modinfo_##field##_exists(struct module *mod) \
758{ \
759 return mod->field != NULL; \
760} \
761static void free_modinfo_##field(struct module *mod) \
762{ \
Daniel Walker22a8bde2007-10-18 03:06:07 -0700763 kfree(mod->field); \
764 mod->field = NULL; \
Matt Domschc988d2b2005-06-23 22:05:15 -0700765} \
766static struct module_attribute modinfo_##field = { \
Tejun Heo7b595752007-06-14 03:45:17 +0900767 .attr = { .name = __stringify(field), .mode = 0444 }, \
Matt Domschc988d2b2005-06-23 22:05:15 -0700768 .show = show_modinfo_##field, \
769 .setup = setup_modinfo_##field, \
770 .test = modinfo_##field##_exists, \
771 .free = free_modinfo_##field, \
772};
773
774MODINFO_ATTR(version);
775MODINFO_ATTR(srcversion);
776
Arjan van de Vene14af7e2008-01-25 21:08:33 +0100777static char last_unloaded_module[MODULE_NAME_LEN+1];
778
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -0800779#ifdef CONFIG_MODULE_UNLOAD
Steven Rostedteb0c5372010-03-29 14:25:18 -0400780
781EXPORT_TRACEPOINT_SYMBOL(module_get);
782
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030783/* MODULE_REF_BASE is the base reference count by kmodule loader. */
784#define MODULE_REF_BASE 1
785
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786/* Init the unload section of the module. */
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600787static int module_unload_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788{
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030789 /*
790 * Initialize reference counter to MODULE_REF_BASE.
791 * refcnt == 0 means module is going.
792 */
793 atomic_set(&mod->refcnt, MODULE_REF_BASE);
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600794
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700795 INIT_LIST_HEAD(&mod->source_list);
796 INIT_LIST_HEAD(&mod->target_list);
Christoph Lametere1783a22010-01-05 15:34:50 +0900797
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 /* Hold reference count during initialization. */
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030799 atomic_inc(&mod->refcnt);
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600800
801 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802}
803
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804/* Does a already use b? */
805static int already_uses(struct module *a, struct module *b)
806{
807 struct module_use *use;
808
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700809 list_for_each_entry(use, &b->source_list, source_list) {
810 if (use->source == a) {
Jim Cromie5e124162011-12-06 12:11:31 -0700811 pr_debug("%s uses %s!\n", a->name, b->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 return 1;
813 }
814 }
Jim Cromie5e124162011-12-06 12:11:31 -0700815 pr_debug("%s does not use %s!\n", a->name, b->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 return 0;
817}
818
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700819/*
820 * Module a uses b
821 * - we add 'a' as a "source", 'b' as a "target" of module use
822 * - the module_use is added to the list of 'b' sources (so
823 * 'b' can walk the list to see who sourced them), and of 'a'
824 * targets (so 'a' can see what modules it targets).
825 */
826static int add_module_usage(struct module *a, struct module *b)
827{
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700828 struct module_use *use;
829
Jim Cromie5e124162011-12-06 12:11:31 -0700830 pr_debug("Allocating new usage for %s.\n", a->name);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700831 use = kmalloc(sizeof(*use), GFP_ATOMIC);
832 if (!use) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800833 pr_warn("%s: out of memory loading\n", a->name);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700834 return -ENOMEM;
835 }
836
837 use->source = a;
838 use->target = b;
839 list_add(&use->source_list, &b->source_list);
840 list_add(&use->target_list, &a->target_list);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700841 return 0;
842}
843
Rusty Russell75676502010-06-05 11:17:36 -0600844/* Module a uses b: caller needs module_mutex() */
Rusty Russell9bea7f22010-06-05 11:17:37 -0600845int ref_module(struct module *a, struct module *b)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846{
Rusty Russellc8e21ce2010-06-05 11:17:35 -0600847 int err;
Kay Sievers270a6c42007-01-18 13:26:15 +0100848
Rusty Russell9bea7f22010-06-05 11:17:37 -0600849 if (b == NULL || already_uses(a, b))
Linus Torvalds218ce732010-05-25 16:48:30 -0700850 return 0;
Linus Torvalds218ce732010-05-25 16:48:30 -0700851
Rusty Russell9bea7f22010-06-05 11:17:37 -0600852 /* If module isn't available, we fail. */
853 err = strong_try_module_get(b);
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500854 if (err)
Rusty Russell9bea7f22010-06-05 11:17:37 -0600855 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700857 err = add_module_usage(a, b);
858 if (err) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859 module_put(b);
Rusty Russell9bea7f22010-06-05 11:17:37 -0600860 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861 }
Rusty Russell9bea7f22010-06-05 11:17:37 -0600862 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863}
Rusty Russell9bea7f22010-06-05 11:17:37 -0600864EXPORT_SYMBOL_GPL(ref_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865
866/* Clear the unload stuff of the module. */
867static void module_unload_free(struct module *mod)
868{
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700869 struct module_use *use, *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870
Rusty Russell75676502010-06-05 11:17:36 -0600871 mutex_lock(&module_mutex);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700872 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
873 struct module *i = use->target;
Jim Cromie5e124162011-12-06 12:11:31 -0700874 pr_debug("%s unusing %s\n", mod->name, i->name);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700875 module_put(i);
876 list_del(&use->source_list);
877 list_del(&use->target_list);
878 kfree(use);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 }
Rusty Russell75676502010-06-05 11:17:36 -0600880 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700881}
882
883#ifdef CONFIG_MODULE_FORCE_UNLOAD
Akinobu Mitafb169792006-01-08 01:04:29 -0800884static inline int try_force_unload(unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885{
886 int ret = (flags & O_TRUNC);
887 if (ret)
Rusty Russell373d4d02013-01-21 17:17:39 +1030888 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 return ret;
890}
891#else
Akinobu Mitafb169792006-01-08 01:04:29 -0800892static inline int try_force_unload(unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893{
894 return 0;
895}
896#endif /* CONFIG_MODULE_FORCE_UNLOAD */
897
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030898/* Try to release refcount of module, 0 means success. */
899static int try_release_module_ref(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900{
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030901 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030903 /* Try to decrement refcnt which we set at loading */
904 ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
905 BUG_ON(ret < 0);
906 if (ret)
907 /* Someone can put this right now, recover with checking */
908 ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700909
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030910 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911}
912
913static int try_stop_module(struct module *mod, int flags, int *forced)
914{
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030915 /* If it's not unused, quit unless we're forcing. */
916 if (try_release_module_ref(mod) != 0) {
917 *forced = try_force_unload(flags);
918 if (!(*forced))
919 return -EWOULDBLOCK;
920 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030922 /* Mark it as dying. */
923 mod->state = MODULE_STATE_GOING;
924
925 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926}
927
Rusty Russelld5db1392015-01-22 11:13:14 +1030928/**
929 * module_refcount - return the refcount or -1 if unloading
930 *
931 * @mod: the module we're checking
932 *
933 * Returns:
934 * -1 if the module is in the process of unloading
935 * otherwise the number of references in the kernel to the module
936 */
937int module_refcount(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938{
Rusty Russelld5db1392015-01-22 11:13:14 +1030939 return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940}
941EXPORT_SYMBOL(module_refcount);
942
943/* This exists whether we can unload or not */
944static void free_module(struct module *mod);
945
Heiko Carstens17da2bd2009-01-14 14:14:10 +0100946SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
947 unsigned int, flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948{
949 struct module *mod;
Greg Kroah-Hartmandfff0a02007-02-23 14:54:57 -0800950 char name[MODULE_NAME_LEN];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700951 int ret, forced = 0;
952
Kees Cook3d433212009-04-02 15:49:29 -0700953 if (!capable(CAP_SYS_MODULE) || modules_disabled)
Greg Kroah-Hartmandfff0a02007-02-23 14:54:57 -0800954 return -EPERM;
955
956 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
957 return -EFAULT;
958 name[MODULE_NAME_LEN-1] = '\0';
959
Tejun Heo3fc1f1e2010-05-06 18:49:20 +0200960 if (mutex_lock_interruptible(&module_mutex) != 0)
961 return -EINTR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962
963 mod = find_module(name);
964 if (!mod) {
965 ret = -ENOENT;
966 goto out;
967 }
968
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700969 if (!list_empty(&mod->source_list)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970 /* Other modules depend on us: get rid of them first. */
971 ret = -EWOULDBLOCK;
972 goto out;
973 }
974
975 /* Doing init or already dying? */
976 if (mod->state != MODULE_STATE_LIVE) {
Rusty Russell3f2b9c92013-09-17 05:48:51 +0930977 /* FIXME: if (force), slam module count damn the torpedoes */
Jim Cromie5e124162011-12-06 12:11:31 -0700978 pr_debug("%s already dying\n", mod->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979 ret = -EBUSY;
980 goto out;
981 }
982
983 /* If it has an init func, it must have an exit func to unload */
Rusty Russellaf49d922007-10-16 23:26:27 -0700984 if (mod->init && !mod->exit) {
Akinobu Mitafb169792006-01-08 01:04:29 -0800985 forced = try_force_unload(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700986 if (!forced) {
987 /* This module can't be removed */
988 ret = -EBUSY;
989 goto out;
990 }
991 }
992
Linus Torvalds1da177e2005-04-16 15:20:36 -0700993 /* Stop the machine so refcounts can't move and disable module. */
994 ret = try_stop_module(mod, flags, &forced);
995 if (ret != 0)
996 goto out;
997
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +0200998 mutex_unlock(&module_mutex);
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300999 /* Final destruction now no one is using it. */
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +02001000 if (mod->exit != NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001 mod->exit();
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +02001002 blocking_notifier_call_chain(&module_notify_list,
1003 MODULE_STATE_GOING, mod);
Arjan van de Ven22a9d642009-01-07 08:45:46 -08001004 async_synchronize_full();
Rusty Russell75676502010-06-05 11:17:36 -06001005
Arjan van de Vene14af7e2008-01-25 21:08:33 +01001006 /* Store the name of the last unloaded module for diagnostic purposes */
Rusty Russellefa53452008-01-29 17:13:20 -05001007 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008
Rusty Russell75676502010-06-05 11:17:36 -06001009 free_module(mod);
1010 return 0;
1011out:
Ashutosh Naik6389a382006-03-23 03:00:46 -08001012 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013 return ret;
1014}
1015
Jianjun Kongd1e99d72008-12-08 14:26:29 +08001016static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001017{
1018 struct module_use *use;
1019 int printed_something = 0;
1020
Rusty Russelld5db1392015-01-22 11:13:14 +10301021 seq_printf(m, " %i ", module_refcount(mod));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001022
Ionut Alexa6da0b562014-11-10 09:31:29 +10301023 /*
1024 * Always include a trailing , so userspace can differentiate
1025 * between this and the old multi-field proc format.
1026 */
Linus Torvalds2c02dfe2010-05-31 12:19:37 -07001027 list_for_each_entry(use, &mod->source_list, source_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028 printed_something = 1;
Linus Torvalds2c02dfe2010-05-31 12:19:37 -07001029 seq_printf(m, "%s,", use->source->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030 }
1031
Linus Torvalds1da177e2005-04-16 15:20:36 -07001032 if (mod->init != NULL && mod->exit == NULL) {
1033 printed_something = 1;
Ionut Alexa6da0b562014-11-10 09:31:29 +10301034 seq_puts(m, "[permanent],");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035 }
1036
1037 if (!printed_something)
Ionut Alexa6da0b562014-11-10 09:31:29 +10301038 seq_puts(m, "-");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001039}
1040
1041void __symbol_put(const char *symbol)
1042{
1043 struct module *owner;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001044
Rusty Russell24da1cb2007-07-15 23:41:46 -07001045 preempt_disable();
Tim Abbott414fd312008-12-05 19:03:56 -05001046 if (!find_symbol(symbol, &owner, NULL, true, false))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001047 BUG();
1048 module_put(owner);
Rusty Russell24da1cb2007-07-15 23:41:46 -07001049 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001050}
1051EXPORT_SYMBOL(__symbol_put);
1052
Rusty Russell7d1d16e2009-08-26 22:02:54 +09301053/* Note this assumes addr is a function, which it currently always is. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054void symbol_put_addr(void *addr)
1055{
Trent Piepho5e376612006-05-15 09:44:06 -07001056 struct module *modaddr;
Rusty Russell7d1d16e2009-08-26 22:02:54 +09301057 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001058
Rusty Russell7d1d16e2009-08-26 22:02:54 +09301059 if (core_kernel_text(a))
Trent Piepho5e376612006-05-15 09:44:06 -07001060 return;
1061
Rusty Russella6e6abd2009-03-31 13:05:31 -06001062 /* module_text_address is safe here: we're supposed to have reference
1063 * to module from symbol_get, so it can't go away. */
Rusty Russell7d1d16e2009-08-26 22:02:54 +09301064 modaddr = __module_text_address(a);
Rusty Russella6e6abd2009-03-31 13:05:31 -06001065 BUG_ON(!modaddr);
Trent Piepho5e376612006-05-15 09:44:06 -07001066 module_put(modaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067}
1068EXPORT_SYMBOL_GPL(symbol_put_addr);
1069
1070static ssize_t show_refcnt(struct module_attribute *mattr,
Kay Sievers4befb022011-07-24 22:06:04 +09301071 struct module_kobject *mk, char *buffer)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072{
Rusty Russelld5db1392015-01-22 11:13:14 +10301073 return sprintf(buffer, "%i\n", module_refcount(mk->mod));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074}
1075
Kay Sieverscca3e702012-01-13 09:32:15 +10301076static struct module_attribute modinfo_refcnt =
1077 __ATTR(refcnt, 0444, show_refcnt, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078
Steven Rostedtd53799b2012-03-26 12:50:52 +10301079void __module_get(struct module *module)
1080{
1081 if (module) {
1082 preempt_disable();
Masami Hiramatsu2f35c412014-11-10 09:29:29 +10301083 atomic_inc(&module->refcnt);
Steven Rostedtd53799b2012-03-26 12:50:52 +10301084 trace_module_get(module, _RET_IP_);
1085 preempt_enable();
1086 }
1087}
1088EXPORT_SYMBOL(__module_get);
1089
1090bool try_module_get(struct module *module)
1091{
1092 bool ret = true;
1093
1094 if (module) {
1095 preempt_disable();
Masami Hiramatsue513cc12014-11-10 09:30:29 +10301096 /* Note: here, we can fail to get a reference */
1097 if (likely(module_is_live(module) &&
1098 atomic_inc_not_zero(&module->refcnt) != 0))
Steven Rostedtd53799b2012-03-26 12:50:52 +10301099 trace_module_get(module, _RET_IP_);
Masami Hiramatsue513cc12014-11-10 09:30:29 +10301100 else
Steven Rostedtd53799b2012-03-26 12:50:52 +10301101 ret = false;
1102
1103 preempt_enable();
1104 }
1105 return ret;
1106}
1107EXPORT_SYMBOL(try_module_get);
1108
Al Virof6a57032006-10-18 01:47:25 -04001109void module_put(struct module *module)
1110{
Masami Hiramatsue513cc12014-11-10 09:30:29 +10301111 int ret;
1112
Al Virof6a57032006-10-18 01:47:25 -04001113 if (module) {
Christoph Lametere1783a22010-01-05 15:34:50 +09001114 preempt_disable();
Masami Hiramatsue513cc12014-11-10 09:30:29 +10301115 ret = atomic_dec_if_positive(&module->refcnt);
1116 WARN_ON(ret < 0); /* Failed to put refcount */
Li Zefanae832d12010-03-24 10:57:43 +08001117 trace_module_put(module, _RET_IP_);
Christoph Lametere1783a22010-01-05 15:34:50 +09001118 preempt_enable();
Al Virof6a57032006-10-18 01:47:25 -04001119 }
1120}
1121EXPORT_SYMBOL(module_put);
1122
Linus Torvalds1da177e2005-04-16 15:20:36 -07001123#else /* !CONFIG_MODULE_UNLOAD */
Jianjun Kongd1e99d72008-12-08 14:26:29 +08001124static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001125{
1126 /* We don't know the usage count, or what modules are using. */
Ionut Alexa6da0b562014-11-10 09:31:29 +10301127 seq_puts(m, " - -");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001128}
1129
1130static inline void module_unload_free(struct module *mod)
1131{
1132}
1133
Rusty Russell9bea7f22010-06-05 11:17:37 -06001134int ref_module(struct module *a, struct module *b)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135{
Rusty Russell9bea7f22010-06-05 11:17:37 -06001136 return strong_try_module_get(b);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137}
Rusty Russell9bea7f22010-06-05 11:17:37 -06001138EXPORT_SYMBOL_GPL(ref_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001139
Rusty Russell9f85a4b2010-08-05 12:59:04 -06001140static inline int module_unload_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141{
Rusty Russell9f85a4b2010-08-05 12:59:04 -06001142 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143}
1144#endif /* CONFIG_MODULE_UNLOAD */
1145
Kevin Winchester53999bf2012-01-15 19:32:55 -04001146static size_t module_flags_taint(struct module *mod, char *buf)
1147{
1148 size_t l = 0;
1149
1150 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
1151 buf[l++] = 'P';
1152 if (mod->taints & (1 << TAINT_OOT_MODULE))
1153 buf[l++] = 'O';
1154 if (mod->taints & (1 << TAINT_FORCED_MODULE))
1155 buf[l++] = 'F';
1156 if (mod->taints & (1 << TAINT_CRAP))
1157 buf[l++] = 'C';
Mathieu Desnoyers66cc69e2014-03-13 12:11:30 +10301158 if (mod->taints & (1 << TAINT_UNSIGNED_MODULE))
Rusty Russell57673c22014-03-31 14:39:57 +10301159 buf[l++] = 'E';
Kevin Winchester53999bf2012-01-15 19:32:55 -04001160 /*
1161 * TAINT_FORCED_RMMOD: could be added.
Dave Jones8c904872014-02-26 10:49:49 -05001162 * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
Kevin Winchester53999bf2012-01-15 19:32:55 -04001163 * apply to modules.
1164 */
1165 return l;
1166}
1167
Kay Sievers1f717402006-11-24 12:15:25 +01001168static ssize_t show_initstate(struct module_attribute *mattr,
Kay Sievers4befb022011-07-24 22:06:04 +09301169 struct module_kobject *mk, char *buffer)
Kay Sievers1f717402006-11-24 12:15:25 +01001170{
1171 const char *state = "unknown";
1172
Kay Sievers4befb022011-07-24 22:06:04 +09301173 switch (mk->mod->state) {
Kay Sievers1f717402006-11-24 12:15:25 +01001174 case MODULE_STATE_LIVE:
1175 state = "live";
1176 break;
1177 case MODULE_STATE_COMING:
1178 state = "coming";
1179 break;
1180 case MODULE_STATE_GOING:
1181 state = "going";
1182 break;
Rusty Russell0d21b0e2013-01-12 11:38:44 +10301183 default:
1184 BUG();
Kay Sievers1f717402006-11-24 12:15:25 +01001185 }
1186 return sprintf(buffer, "%s\n", state);
1187}
1188
Kay Sieverscca3e702012-01-13 09:32:15 +10301189static struct module_attribute modinfo_initstate =
1190 __ATTR(initstate, 0444, show_initstate, NULL);
Kay Sievers1f717402006-11-24 12:15:25 +01001191
Kay Sievers88bfa322011-07-24 22:06:04 +09301192static ssize_t store_uevent(struct module_attribute *mattr,
1193 struct module_kobject *mk,
1194 const char *buffer, size_t count)
1195{
1196 enum kobject_action action;
1197
1198 if (kobject_action_type(buffer, count, &action) == 0)
1199 kobject_uevent(&mk->kobj, action);
1200 return count;
1201}
1202
Kay Sieverscca3e702012-01-13 09:32:15 +10301203struct module_attribute module_uevent =
1204 __ATTR(uevent, 0200, NULL, store_uevent);
1205
1206static ssize_t show_coresize(struct module_attribute *mattr,
1207 struct module_kobject *mk, char *buffer)
1208{
1209 return sprintf(buffer, "%u\n", mk->mod->core_size);
1210}
1211
1212static struct module_attribute modinfo_coresize =
1213 __ATTR(coresize, 0444, show_coresize, NULL);
1214
1215static ssize_t show_initsize(struct module_attribute *mattr,
1216 struct module_kobject *mk, char *buffer)
1217{
1218 return sprintf(buffer, "%u\n", mk->mod->init_size);
1219}
1220
1221static struct module_attribute modinfo_initsize =
1222 __ATTR(initsize, 0444, show_initsize, NULL);
1223
1224static ssize_t show_taint(struct module_attribute *mattr,
1225 struct module_kobject *mk, char *buffer)
1226{
1227 size_t l;
1228
1229 l = module_flags_taint(mk->mod, buffer);
1230 buffer[l++] = '\n';
1231 return l;
1232}
1233
1234static struct module_attribute modinfo_taint =
1235 __ATTR(taint, 0444, show_taint, NULL);
Kay Sievers88bfa322011-07-24 22:06:04 +09301236
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001237static struct module_attribute *modinfo_attrs[] = {
Kay Sieverscca3e702012-01-13 09:32:15 +10301238 &module_uevent,
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001239 &modinfo_version,
1240 &modinfo_srcversion,
Kay Sieverscca3e702012-01-13 09:32:15 +10301241 &modinfo_initstate,
1242 &modinfo_coresize,
1243 &modinfo_initsize,
1244 &modinfo_taint,
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001245#ifdef CONFIG_MODULE_UNLOAD
Kay Sieverscca3e702012-01-13 09:32:15 +10301246 &modinfo_refcnt,
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001247#endif
1248 NULL,
1249};
1250
Linus Torvalds1da177e2005-04-16 15:20:36 -07001251static const char vermagic[] = VERMAGIC_STRING;
1252
Rusty Russellc6e665c2009-03-31 13:05:33 -06001253static int try_to_force_load(struct module *mod, const char *reason)
Linus Torvalds826e4502008-05-04 17:04:16 -07001254{
1255#ifdef CONFIG_MODULE_FORCE_LOAD
Andi Kleen25ddbb12008-10-15 22:01:41 -07001256 if (!test_taint(TAINT_FORCED_MODULE))
Andrew Mortonbddb12b2013-11-12 15:11:28 -08001257 pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
Rusty Russell373d4d02013-01-21 17:17:39 +10301258 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
Linus Torvalds826e4502008-05-04 17:04:16 -07001259 return 0;
1260#else
1261 return -ENOEXEC;
1262#endif
1263}
1264
Linus Torvalds1da177e2005-04-16 15:20:36 -07001265#ifdef CONFIG_MODVERSIONS
Rusty Russelld4703ae2009-12-15 16:28:32 -06001266/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
1267static unsigned long maybe_relocated(unsigned long crc,
1268 const struct module *crc_owner)
1269{
1270#ifdef ARCH_RELOCATES_KCRCTAB
1271 if (crc_owner == NULL)
1272 return crc - (unsigned long)reloc_start;
1273#endif
1274 return crc;
1275}
1276
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277static int check_version(Elf_Shdr *sechdrs,
1278 unsigned int versindex,
1279 const char *symname,
Ionut Alexa6da0b562014-11-10 09:31:29 +10301280 struct module *mod,
Rusty Russelld4703ae2009-12-15 16:28:32 -06001281 const unsigned long *crc,
1282 const struct module *crc_owner)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283{
1284 unsigned int i, num_versions;
1285 struct modversion_info *versions;
1286
1287 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1288 if (!crc)
1289 return 1;
1290
Rusty Russella5dd6972008-05-09 16:24:21 +10001291 /* No versions at all? modprobe --force does this. */
1292 if (versindex == 0)
1293 return try_to_force_load(mod, symname) == 0;
1294
Linus Torvalds1da177e2005-04-16 15:20:36 -07001295 versions = (void *) sechdrs[versindex].sh_addr;
1296 num_versions = sechdrs[versindex].sh_size
1297 / sizeof(struct modversion_info);
1298
1299 for (i = 0; i < num_versions; i++) {
1300 if (strcmp(versions[i].name, symname) != 0)
1301 continue;
1302
Rusty Russelld4703ae2009-12-15 16:28:32 -06001303 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001304 return 1;
Jim Cromie5e124162011-12-06 12:11:31 -07001305 pr_debug("Found checksum %lX vs module %lX\n",
Rusty Russelld4703ae2009-12-15 16:28:32 -06001306 maybe_relocated(*crc, crc_owner), versions[i].crc);
Linus Torvalds826e4502008-05-04 17:04:16 -07001307 goto bad_version;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001308 }
Linus Torvalds826e4502008-05-04 17:04:16 -07001309
Andrew Mortonbddb12b2013-11-12 15:11:28 -08001310 pr_warn("%s: no symbol version for %s\n", mod->name, symname);
Rusty Russella5dd6972008-05-09 16:24:21 +10001311 return 0;
Linus Torvalds826e4502008-05-04 17:04:16 -07001312
1313bad_version:
Ionut Alexa6da0b562014-11-10 09:31:29 +10301314 pr_warn("%s: disagrees about version of symbol %s\n",
Linus Torvalds826e4502008-05-04 17:04:16 -07001315 mod->name, symname);
1316 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001317}
1318
1319static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1320 unsigned int versindex,
1321 struct module *mod)
1322{
1323 const unsigned long *crc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001324
Peter Zijlstra926a59b2015-05-27 11:09:35 +09301325 /*
1326 * Since this should be found in kernel (which can't be removed), no
1327 * locking is necessary -- use preempt_disable() to placate lockdep.
1328 */
1329 preempt_disable();
Rusty Russellb92021b2013-03-15 15:04:17 +10301330 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
Peter Zijlstra926a59b2015-05-27 11:09:35 +09301331 &crc, true, false)) {
1332 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001333 BUG();
Peter Zijlstra926a59b2015-05-27 11:09:35 +09301334 }
1335 preempt_enable();
James Hogana4b6a772013-03-18 19:38:56 +10301336 return check_version(sechdrs, versindex,
1337 VMLINUX_SYMBOL_STR(module_layout), mod, crc,
Rusty Russelld4703ae2009-12-15 16:28:32 -06001338 NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001339}
1340
Rusty Russell91e37a72008-05-09 16:25:28 +10001341/* First part is kernel version, which we ignore if module has crcs. */
1342static inline int same_magic(const char *amagic, const char *bmagic,
1343 bool has_crcs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001344{
Rusty Russell91e37a72008-05-09 16:25:28 +10001345 if (has_crcs) {
1346 amagic += strcspn(amagic, " ");
1347 bmagic += strcspn(bmagic, " ");
1348 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001349 return strcmp(amagic, bmagic) == 0;
1350}
1351#else
1352static inline int check_version(Elf_Shdr *sechdrs,
1353 unsigned int versindex,
1354 const char *symname,
Ionut Alexa6da0b562014-11-10 09:31:29 +10301355 struct module *mod,
Rusty Russelld4703ae2009-12-15 16:28:32 -06001356 const unsigned long *crc,
1357 const struct module *crc_owner)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001358{
1359 return 1;
1360}
1361
1362static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1363 unsigned int versindex,
1364 struct module *mod)
1365{
1366 return 1;
1367}
1368
Rusty Russell91e37a72008-05-09 16:25:28 +10001369static inline int same_magic(const char *amagic, const char *bmagic,
1370 bool has_crcs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001371{
1372 return strcmp(amagic, bmagic) == 0;
1373}
1374#endif /* CONFIG_MODVERSIONS */
1375
Rusty Russell75676502010-06-05 11:17:36 -06001376/* Resolve a symbol for this module. I.e. if we find one, record usage. */
Rusty Russell49668682010-08-05 12:59:10 -06001377static const struct kernel_symbol *resolve_symbol(struct module *mod,
1378 const struct load_info *info,
Tim Abbott414fd312008-12-05 19:03:56 -05001379 const char *name,
Rusty Russell9bea7f22010-06-05 11:17:37 -06001380 char ownername[])
Linus Torvalds1da177e2005-04-16 15:20:36 -07001381{
1382 struct module *owner;
Tim Abbott414fd312008-12-05 19:03:56 -05001383 const struct kernel_symbol *sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001384 const unsigned long *crc;
Rusty Russell9bea7f22010-06-05 11:17:37 -06001385 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001386
Peter Zijlstrad64810f2015-02-11 15:01:13 +10301387 /*
1388 * The module_mutex should not be a heavily contended lock;
1389 * if we get the occasional sleep here, we'll go an extra iteration
1390 * in the wait_event_interruptible(), which is harmless.
1391 */
1392 sched_annotate_sleep();
Rusty Russell75676502010-06-05 11:17:36 -06001393 mutex_lock(&module_mutex);
Tim Abbott414fd312008-12-05 19:03:56 -05001394 sym = find_symbol(name, &owner, &crc,
Andi Kleen25ddbb12008-10-15 22:01:41 -07001395 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
Rusty Russell9bea7f22010-06-05 11:17:37 -06001396 if (!sym)
1397 goto unlock;
1398
Rusty Russell49668682010-08-05 12:59:10 -06001399 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1400 owner)) {
Rusty Russell9bea7f22010-06-05 11:17:37 -06001401 sym = ERR_PTR(-EINVAL);
1402 goto getname;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001403 }
Rusty Russell9bea7f22010-06-05 11:17:37 -06001404
1405 err = ref_module(mod, owner);
1406 if (err) {
1407 sym = ERR_PTR(err);
1408 goto getname;
1409 }
1410
1411getname:
1412 /* We must make copy under the lock if we failed to get ref. */
1413 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1414unlock:
Rusty Russell75676502010-06-05 11:17:36 -06001415 mutex_unlock(&module_mutex);
Linus Torvalds218ce732010-05-25 16:48:30 -07001416 return sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417}
1418
Rusty Russell49668682010-08-05 12:59:10 -06001419static const struct kernel_symbol *
1420resolve_symbol_wait(struct module *mod,
1421 const struct load_info *info,
1422 const char *name)
Rusty Russell9bea7f22010-06-05 11:17:37 -06001423{
1424 const struct kernel_symbol *ksym;
Rusty Russell49668682010-08-05 12:59:10 -06001425 char owner[MODULE_NAME_LEN];
Rusty Russell9bea7f22010-06-05 11:17:37 -06001426
1427 if (wait_event_interruptible_timeout(module_wq,
Rusty Russell49668682010-08-05 12:59:10 -06001428 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1429 || PTR_ERR(ksym) != -EBUSY,
Rusty Russell9bea7f22010-06-05 11:17:37 -06001430 30 * HZ) <= 0) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08001431 pr_warn("%s: gave up waiting for init of module %s.\n",
1432 mod->name, owner);
Rusty Russell9bea7f22010-06-05 11:17:37 -06001433 }
1434 return ksym;
1435}
1436
Linus Torvalds1da177e2005-04-16 15:20:36 -07001437/*
1438 * /sys/module/foo/sections stuff
1439 * J. Corbet <corbet@lwn.net>
1440 */
Rusty Russell8f6d0372010-08-05 12:59:09 -06001441#ifdef CONFIG_SYSFS
Ben Hutchings10b465a2009-12-19 14:43:01 +00001442
Rusty Russell8f6d0372010-08-05 12:59:09 -06001443#ifdef CONFIG_KALLSYMS
Ben Hutchings10b465a2009-12-19 14:43:01 +00001444static inline bool sect_empty(const Elf_Shdr *sect)
1445{
1446 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1447}
1448
Ionut Alexa6da0b562014-11-10 09:31:29 +10301449struct module_sect_attr {
Rusty Russella58730c2008-03-13 09:03:44 +00001450 struct module_attribute mattr;
1451 char *name;
1452 unsigned long address;
1453};
1454
Ionut Alexa6da0b562014-11-10 09:31:29 +10301455struct module_sect_attrs {
Rusty Russella58730c2008-03-13 09:03:44 +00001456 struct attribute_group grp;
1457 unsigned int nsections;
1458 struct module_sect_attr attrs[0];
1459};
1460
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461static ssize_t module_sect_show(struct module_attribute *mattr,
Kay Sievers4befb022011-07-24 22:06:04 +09301462 struct module_kobject *mk, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001463{
1464 struct module_sect_attr *sattr =
1465 container_of(mattr, struct module_sect_attr, mattr);
Kees Cook9f36e2c2011-03-22 16:34:22 -07001466 return sprintf(buf, "0x%pK\n", (void *)sattr->address);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001467}
1468
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001469static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1470{
Rusty Russella58730c2008-03-13 09:03:44 +00001471 unsigned int section;
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001472
1473 for (section = 0; section < sect_attrs->nsections; section++)
1474 kfree(sect_attrs->attrs[section].name);
1475 kfree(sect_attrs);
1476}
1477
Rusty Russell8f6d0372010-08-05 12:59:09 -06001478static void add_sect_attrs(struct module *mod, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001479{
1480 unsigned int nloaded = 0, i, size[2];
1481 struct module_sect_attrs *sect_attrs;
1482 struct module_sect_attr *sattr;
1483 struct attribute **gattr;
Daniel Walker22a8bde2007-10-18 03:06:07 -07001484
Linus Torvalds1da177e2005-04-16 15:20:36 -07001485 /* Count loaded sections and allocate structures */
Rusty Russell8f6d0372010-08-05 12:59:09 -06001486 for (i = 0; i < info->hdr->e_shnum; i++)
1487 if (!sect_empty(&info->sechdrs[i]))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001488 nloaded++;
1489 size[0] = ALIGN(sizeof(*sect_attrs)
1490 + nloaded * sizeof(sect_attrs->attrs[0]),
1491 sizeof(sect_attrs->grp.attrs[0]));
1492 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001493 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1494 if (sect_attrs == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001495 return;
1496
1497 /* Setup section attributes. */
1498 sect_attrs->grp.name = "sections";
1499 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1500
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001501 sect_attrs->nsections = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001502 sattr = &sect_attrs->attrs[0];
1503 gattr = &sect_attrs->grp.attrs[0];
Rusty Russell8f6d0372010-08-05 12:59:09 -06001504 for (i = 0; i < info->hdr->e_shnum; i++) {
1505 Elf_Shdr *sec = &info->sechdrs[i];
1506 if (sect_empty(sec))
Helge Deller35dead42009-12-03 00:29:15 +01001507 continue;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001508 sattr->address = sec->sh_addr;
1509 sattr->name = kstrdup(info->secstrings + sec->sh_name,
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001510 GFP_KERNEL);
1511 if (sattr->name == NULL)
1512 goto out;
1513 sect_attrs->nsections++;
Eric W. Biederman361795b2010-02-12 13:41:56 -08001514 sysfs_attr_init(&sattr->mattr.attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001515 sattr->mattr.show = module_sect_show;
1516 sattr->mattr.store = NULL;
1517 sattr->mattr.attr.name = sattr->name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001518 sattr->mattr.attr.mode = S_IRUGO;
1519 *(gattr++) = &(sattr++)->mattr.attr;
1520 }
1521 *gattr = NULL;
1522
1523 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1524 goto out;
1525
1526 mod->sect_attrs = sect_attrs;
1527 return;
1528 out:
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001529 free_sect_attrs(sect_attrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530}
1531
1532static void remove_sect_attrs(struct module *mod)
1533{
1534 if (mod->sect_attrs) {
1535 sysfs_remove_group(&mod->mkobj.kobj,
1536 &mod->sect_attrs->grp);
1537 /* We are positive that no one is using any sect attrs
1538 * at this point. Deallocate immediately. */
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001539 free_sect_attrs(mod->sect_attrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001540 mod->sect_attrs = NULL;
1541 }
1542}
1543
Roland McGrath6d760132007-10-16 23:26:40 -07001544/*
1545 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1546 */
1547
1548struct module_notes_attrs {
1549 struct kobject *dir;
1550 unsigned int notes;
1551 struct bin_attribute attrs[0];
1552};
1553
Chris Wright2c3c8be2010-05-12 18:28:57 -07001554static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
Roland McGrath6d760132007-10-16 23:26:40 -07001555 struct bin_attribute *bin_attr,
1556 char *buf, loff_t pos, size_t count)
1557{
1558 /*
1559 * The caller checked the pos and count against our size.
1560 */
1561 memcpy(buf, bin_attr->private + pos, count);
1562 return count;
1563}
1564
1565static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1566 unsigned int i)
1567{
1568 if (notes_attrs->dir) {
1569 while (i-- > 0)
1570 sysfs_remove_bin_file(notes_attrs->dir,
1571 &notes_attrs->attrs[i]);
Alexey Dobriyane9432092008-09-23 23:51:11 +04001572 kobject_put(notes_attrs->dir);
Roland McGrath6d760132007-10-16 23:26:40 -07001573 }
1574 kfree(notes_attrs);
1575}
1576
Rusty Russell8f6d0372010-08-05 12:59:09 -06001577static void add_notes_attrs(struct module *mod, const struct load_info *info)
Roland McGrath6d760132007-10-16 23:26:40 -07001578{
1579 unsigned int notes, loaded, i;
1580 struct module_notes_attrs *notes_attrs;
1581 struct bin_attribute *nattr;
1582
Ingo Molnarea6bff32009-08-28 10:44:56 +02001583 /* failed to create section attributes, so can't create notes */
1584 if (!mod->sect_attrs)
1585 return;
1586
Roland McGrath6d760132007-10-16 23:26:40 -07001587 /* Count notes sections and allocate structures. */
1588 notes = 0;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001589 for (i = 0; i < info->hdr->e_shnum; i++)
1590 if (!sect_empty(&info->sechdrs[i]) &&
1591 (info->sechdrs[i].sh_type == SHT_NOTE))
Roland McGrath6d760132007-10-16 23:26:40 -07001592 ++notes;
1593
1594 if (notes == 0)
1595 return;
1596
1597 notes_attrs = kzalloc(sizeof(*notes_attrs)
1598 + notes * sizeof(notes_attrs->attrs[0]),
1599 GFP_KERNEL);
1600 if (notes_attrs == NULL)
1601 return;
1602
1603 notes_attrs->notes = notes;
1604 nattr = &notes_attrs->attrs[0];
Rusty Russell8f6d0372010-08-05 12:59:09 -06001605 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1606 if (sect_empty(&info->sechdrs[i]))
Roland McGrath6d760132007-10-16 23:26:40 -07001607 continue;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001608 if (info->sechdrs[i].sh_type == SHT_NOTE) {
Eric W. Biederman361795b2010-02-12 13:41:56 -08001609 sysfs_bin_attr_init(nattr);
Roland McGrath6d760132007-10-16 23:26:40 -07001610 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1611 nattr->attr.mode = S_IRUGO;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001612 nattr->size = info->sechdrs[i].sh_size;
1613 nattr->private = (void *) info->sechdrs[i].sh_addr;
Roland McGrath6d760132007-10-16 23:26:40 -07001614 nattr->read = module_notes_read;
1615 ++nattr;
1616 }
1617 ++loaded;
1618 }
1619
Greg Kroah-Hartman4ff6abf2007-11-05 22:24:43 -08001620 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
Roland McGrath6d760132007-10-16 23:26:40 -07001621 if (!notes_attrs->dir)
1622 goto out;
1623
1624 for (i = 0; i < notes; ++i)
1625 if (sysfs_create_bin_file(notes_attrs->dir,
1626 &notes_attrs->attrs[i]))
1627 goto out;
1628
1629 mod->notes_attrs = notes_attrs;
1630 return;
1631
1632 out:
1633 free_notes_attrs(notes_attrs, i);
1634}
1635
1636static void remove_notes_attrs(struct module *mod)
1637{
1638 if (mod->notes_attrs)
1639 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1640}
1641
Linus Torvalds1da177e2005-04-16 15:20:36 -07001642#else
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001643
Rusty Russell8f6d0372010-08-05 12:59:09 -06001644static inline void add_sect_attrs(struct module *mod,
1645 const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001646{
1647}
1648
1649static inline void remove_sect_attrs(struct module *mod)
1650{
1651}
Roland McGrath6d760132007-10-16 23:26:40 -07001652
Rusty Russell8f6d0372010-08-05 12:59:09 -06001653static inline void add_notes_attrs(struct module *mod,
1654 const struct load_info *info)
Roland McGrath6d760132007-10-16 23:26:40 -07001655{
1656}
1657
1658static inline void remove_notes_attrs(struct module *mod)
1659{
1660}
Rusty Russell8f6d0372010-08-05 12:59:09 -06001661#endif /* CONFIG_KALLSYMS */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001662
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001663static void add_usage_links(struct module *mod)
1664{
1665#ifdef CONFIG_MODULE_UNLOAD
1666 struct module_use *use;
1667 int nowarn;
1668
Rusty Russell75676502010-06-05 11:17:36 -06001669 mutex_lock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001670 list_for_each_entry(use, &mod->target_list, target_list) {
1671 nowarn = sysfs_create_link(use->target->holders_dir,
1672 &mod->mkobj.kobj, mod->name);
1673 }
Rusty Russell75676502010-06-05 11:17:36 -06001674 mutex_unlock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001675#endif
1676}
1677
1678static void del_usage_links(struct module *mod)
1679{
1680#ifdef CONFIG_MODULE_UNLOAD
1681 struct module_use *use;
1682
Rusty Russell75676502010-06-05 11:17:36 -06001683 mutex_lock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001684 list_for_each_entry(use, &mod->target_list, target_list)
1685 sysfs_remove_link(use->target->holders_dir, mod->name);
Rusty Russell75676502010-06-05 11:17:36 -06001686 mutex_unlock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001687#endif
1688}
1689
Rusty Russell6407ebb22010-06-05 11:17:36 -06001690static int module_add_modinfo_attrs(struct module *mod)
Matt Domschc988d2b2005-06-23 22:05:15 -07001691{
1692 struct module_attribute *attr;
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001693 struct module_attribute *temp_attr;
Matt Domschc988d2b2005-06-23 22:05:15 -07001694 int error = 0;
1695 int i;
1696
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001697 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1698 (ARRAY_SIZE(modinfo_attrs) + 1)),
1699 GFP_KERNEL);
1700 if (!mod->modinfo_attrs)
1701 return -ENOMEM;
1702
1703 temp_attr = mod->modinfo_attrs;
Matt Domschc988d2b2005-06-23 22:05:15 -07001704 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1705 if (!attr->test ||
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001706 (attr->test && attr->test(mod))) {
1707 memcpy(temp_attr, attr, sizeof(*temp_attr));
Eric W. Biederman361795b2010-02-12 13:41:56 -08001708 sysfs_attr_init(&temp_attr->attr);
Ionut Alexa6da0b562014-11-10 09:31:29 +10301709 error = sysfs_create_file(&mod->mkobj.kobj,
1710 &temp_attr->attr);
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001711 ++temp_attr;
1712 }
Matt Domschc988d2b2005-06-23 22:05:15 -07001713 }
1714 return error;
1715}
1716
Rusty Russell6407ebb22010-06-05 11:17:36 -06001717static void module_remove_modinfo_attrs(struct module *mod)
Matt Domschc988d2b2005-06-23 22:05:15 -07001718{
1719 struct module_attribute *attr;
1720 int i;
1721
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001722 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1723 /* pick a field to test for end of list */
1724 if (!attr->attr.name)
1725 break;
Ionut Alexa6da0b562014-11-10 09:31:29 +10301726 sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001727 if (attr->free)
1728 attr->free(mod);
Matt Domschc988d2b2005-06-23 22:05:15 -07001729 }
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001730 kfree(mod->modinfo_attrs);
Matt Domschc988d2b2005-06-23 22:05:15 -07001731}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001732
Li Zhong942e4432013-09-03 16:33:57 +09301733static void mod_kobject_put(struct module *mod)
1734{
1735 DECLARE_COMPLETION_ONSTACK(c);
1736 mod->mkobj.kobj_completion = &c;
1737 kobject_put(&mod->mkobj.kobj);
1738 wait_for_completion(&c);
1739}
1740
Rusty Russell6407ebb22010-06-05 11:17:36 -06001741static int mod_sysfs_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001742{
1743 int err;
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001744 struct kobject *kobj;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001745
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -07001746 if (!module_sysfs_initialized) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08001747 pr_err("%s: module sysfs not initialized\n", mod->name);
Ed Swierk1cc5f712006-09-25 16:25:36 -07001748 err = -EINVAL;
1749 goto out;
1750 }
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001751
1752 kobj = kset_find_obj(module_kset, mod->name);
1753 if (kobj) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08001754 pr_err("%s: module is already loaded\n", mod->name);
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001755 kobject_put(kobj);
1756 err = -EINVAL;
1757 goto out;
1758 }
1759
Linus Torvalds1da177e2005-04-16 15:20:36 -07001760 mod->mkobj.mod = mod;
Kay Sieverse17e0f52006-11-24 12:15:25 +01001761
Greg Kroah-Hartmanac3c8142007-12-17 23:05:35 -07001762 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1763 mod->mkobj.kobj.kset = module_kset;
1764 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1765 "%s", mod->name);
1766 if (err)
Li Zhong942e4432013-09-03 16:33:57 +09301767 mod_kobject_put(mod);
Kay Sievers270a6c42007-01-18 13:26:15 +01001768
Kay Sievers97c146e2007-11-29 23:46:11 +01001769 /* delay uevent until full sysfs population */
Kay Sievers270a6c42007-01-18 13:26:15 +01001770out:
1771 return err;
1772}
1773
Rusty Russell6407ebb22010-06-05 11:17:36 -06001774static int mod_sysfs_setup(struct module *mod,
Rusty Russell8f6d0372010-08-05 12:59:09 -06001775 const struct load_info *info,
Kay Sievers270a6c42007-01-18 13:26:15 +01001776 struct kernel_param *kparam,
1777 unsigned int num_params)
1778{
1779 int err;
1780
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001781 err = mod_sysfs_init(mod);
1782 if (err)
1783 goto out;
1784
Greg Kroah-Hartman4ff6abf2007-11-05 22:24:43 -08001785 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
Akinobu Mita240936e2007-04-26 00:12:09 -07001786 if (!mod->holders_dir) {
1787 err = -ENOMEM;
Kay Sievers270a6c42007-01-18 13:26:15 +01001788 goto out_unreg;
Akinobu Mita240936e2007-04-26 00:12:09 -07001789 }
Kay Sievers270a6c42007-01-18 13:26:15 +01001790
Linus Torvalds1da177e2005-04-16 15:20:36 -07001791 err = module_param_sysfs_setup(mod, kparam, num_params);
1792 if (err)
Kay Sievers270a6c42007-01-18 13:26:15 +01001793 goto out_unreg_holders;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001794
Matt Domschc988d2b2005-06-23 22:05:15 -07001795 err = module_add_modinfo_attrs(mod);
1796 if (err)
Kay Sieverse17e0f52006-11-24 12:15:25 +01001797 goto out_unreg_param;
Matt Domschc988d2b2005-06-23 22:05:15 -07001798
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001799 add_usage_links(mod);
Rusty Russell8f6d0372010-08-05 12:59:09 -06001800 add_sect_attrs(mod, info);
1801 add_notes_attrs(mod, info);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001802
Kay Sieverse17e0f52006-11-24 12:15:25 +01001803 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001804 return 0;
1805
Kay Sieverse17e0f52006-11-24 12:15:25 +01001806out_unreg_param:
1807 module_param_sysfs_remove(mod);
Kay Sievers270a6c42007-01-18 13:26:15 +01001808out_unreg_holders:
Greg Kroah-Hartman78a2d902007-12-20 08:13:05 -08001809 kobject_put(mod->holders_dir);
Kay Sievers270a6c42007-01-18 13:26:15 +01001810out_unreg:
Li Zhong942e4432013-09-03 16:33:57 +09301811 mod_kobject_put(mod);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001812out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001813 return err;
1814}
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001815
1816static void mod_sysfs_fini(struct module *mod)
1817{
Rusty Russell8f6d0372010-08-05 12:59:09 -06001818 remove_notes_attrs(mod);
1819 remove_sect_attrs(mod);
Li Zhong942e4432013-09-03 16:33:57 +09301820 mod_kobject_put(mod);
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001821}
1822
Rusty Russellcf2fde72015-06-26 06:44:38 +09301823static void init_param_lock(struct module *mod)
1824{
1825 mutex_init(&mod->param_lock);
1826}
Rusty Russell8f6d0372010-08-05 12:59:09 -06001827#else /* !CONFIG_SYSFS */
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001828
Rusty Russell8f6d0372010-08-05 12:59:09 -06001829static int mod_sysfs_setup(struct module *mod,
1830 const struct load_info *info,
Rusty Russell6407ebb22010-06-05 11:17:36 -06001831 struct kernel_param *kparam,
1832 unsigned int num_params)
1833{
1834 return 0;
1835}
1836
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001837static void mod_sysfs_fini(struct module *mod)
1838{
1839}
1840
Rusty Russell36b03602010-08-05 12:59:09 -06001841static void module_remove_modinfo_attrs(struct module *mod)
1842{
1843}
1844
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001845static void del_usage_links(struct module *mod)
1846{
1847}
1848
Rusty Russellcf2fde72015-06-26 06:44:38 +09301849static void init_param_lock(struct module *mod)
1850{
1851}
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001852#endif /* CONFIG_SYSFS */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001853
Rusty Russell36b03602010-08-05 12:59:09 -06001854static void mod_sysfs_teardown(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001855{
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001856 del_usage_links(mod);
Matt Domschc988d2b2005-06-23 22:05:15 -07001857 module_remove_modinfo_attrs(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001858 module_param_sysfs_remove(mod);
Greg Kroah-Hartman78a2d902007-12-20 08:13:05 -08001859 kobject_put(mod->mkobj.drivers_dir);
1860 kobject_put(mod->holders_dir);
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001861 mod_sysfs_fini(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001862}
1863
matthieu castet84e1c6b2010-11-16 22:35:16 +01001864#ifdef CONFIG_DEBUG_SET_MODULE_RONX
1865/*
1866 * LKM RO/NX protection: protect module's text/ro-data
1867 * from modification and any data from execution.
1868 */
1869void set_page_attributes(void *start, void *end, int (*set)(unsigned long start, int num_pages))
1870{
1871 unsigned long begin_pfn = PFN_DOWN((unsigned long)start);
1872 unsigned long end_pfn = PFN_DOWN((unsigned long)end);
1873
1874 if (end_pfn > begin_pfn)
1875 set(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1876}
1877
1878static void set_section_ro_nx(void *base,
1879 unsigned long text_size,
1880 unsigned long ro_size,
1881 unsigned long total_size)
1882{
1883 /* begin and end PFNs of the current subsection */
1884 unsigned long begin_pfn;
1885 unsigned long end_pfn;
1886
1887 /*
1888 * Set RO for module text and RO-data:
1889 * - Always protect first page.
1890 * - Do not protect last partial page.
1891 */
1892 if (ro_size > 0)
1893 set_page_attributes(base, base + ro_size, set_memory_ro);
1894
1895 /*
1896 * Set NX permissions for module data:
1897 * - Do not protect first partial page.
1898 * - Always protect last page.
1899 */
1900 if (total_size > text_size) {
1901 begin_pfn = PFN_UP((unsigned long)base + text_size);
1902 end_pfn = PFN_UP((unsigned long)base + total_size);
1903 if (end_pfn > begin_pfn)
1904 set_memory_nx(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
1905 }
1906}
1907
Jan Glauber01526ed2011-05-19 16:55:26 -06001908static void unset_module_core_ro_nx(struct module *mod)
matthieu castet84e1c6b2010-11-16 22:35:16 +01001909{
Jan Glauber01526ed2011-05-19 16:55:26 -06001910 set_page_attributes(mod->module_core + mod->core_text_size,
1911 mod->module_core + mod->core_size,
1912 set_memory_x);
1913 set_page_attributes(mod->module_core,
1914 mod->module_core + mod->core_ro_size,
1915 set_memory_rw);
1916}
1917
1918static void unset_module_init_ro_nx(struct module *mod)
1919{
1920 set_page_attributes(mod->module_init + mod->init_text_size,
1921 mod->module_init + mod->init_size,
1922 set_memory_x);
1923 set_page_attributes(mod->module_init,
1924 mod->module_init + mod->init_ro_size,
1925 set_memory_rw);
matthieu castet84e1c6b2010-11-16 22:35:16 +01001926}
1927
1928/* Iterate through all modules and set each module's text as RW */
Daniel J Blueman5d05c702011-03-08 22:01:47 +08001929void set_all_modules_text_rw(void)
matthieu castet84e1c6b2010-11-16 22:35:16 +01001930{
1931 struct module *mod;
1932
1933 mutex_lock(&module_mutex);
1934 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10301935 if (mod->state == MODULE_STATE_UNFORMED)
1936 continue;
matthieu castet84e1c6b2010-11-16 22:35:16 +01001937 if ((mod->module_core) && (mod->core_text_size)) {
1938 set_page_attributes(mod->module_core,
1939 mod->module_core + mod->core_text_size,
1940 set_memory_rw);
1941 }
1942 if ((mod->module_init) && (mod->init_text_size)) {
1943 set_page_attributes(mod->module_init,
1944 mod->module_init + mod->init_text_size,
1945 set_memory_rw);
1946 }
1947 }
1948 mutex_unlock(&module_mutex);
1949}
1950
1951/* Iterate through all modules and set each module's text as RO */
Daniel J Blueman5d05c702011-03-08 22:01:47 +08001952void set_all_modules_text_ro(void)
matthieu castet84e1c6b2010-11-16 22:35:16 +01001953{
1954 struct module *mod;
1955
1956 mutex_lock(&module_mutex);
1957 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10301958 if (mod->state == MODULE_STATE_UNFORMED)
1959 continue;
matthieu castet84e1c6b2010-11-16 22:35:16 +01001960 if ((mod->module_core) && (mod->core_text_size)) {
1961 set_page_attributes(mod->module_core,
1962 mod->module_core + mod->core_text_size,
1963 set_memory_ro);
1964 }
1965 if ((mod->module_init) && (mod->init_text_size)) {
1966 set_page_attributes(mod->module_init,
1967 mod->module_init + mod->init_text_size,
1968 set_memory_ro);
1969 }
1970 }
1971 mutex_unlock(&module_mutex);
1972}
1973#else
1974static inline void set_section_ro_nx(void *base, unsigned long text_size, unsigned long ro_size, unsigned long total_size) { }
Jan Glauber01526ed2011-05-19 16:55:26 -06001975static void unset_module_core_ro_nx(struct module *mod) { }
1976static void unset_module_init_ro_nx(struct module *mod) { }
matthieu castet84e1c6b2010-11-16 22:35:16 +01001977#endif
1978
Rusty Russellbe1f2212015-01-20 09:07:05 +10301979void __weak module_memfree(void *module_region)
Jonas Bonn74e08fc2011-06-30 21:22:11 +02001980{
1981 vfree(module_region);
1982}
1983
1984void __weak module_arch_cleanup(struct module *mod)
1985{
1986}
1987
Rusty Russelld453cde2015-01-20 09:07:04 +10301988void __weak module_arch_freeing_init(struct module *mod)
1989{
1990}
1991
Rusty Russell75676502010-06-05 11:17:36 -06001992/* Free a module, remove from lists, etc. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001993static void free_module(struct module *mod)
1994{
Li Zefan7ead8b82009-08-17 16:56:28 +08001995 trace_module_free(mod);
1996
Rusty Russell36b03602010-08-05 12:59:09 -06001997 mod_sysfs_teardown(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001998
Rusty Russell944a1fa2013-04-17 13:20:03 +09301999 /* We leave it in list to prevent duplicate loads, but make sure
2000 * that noone uses it while it's being deconstructed. */
Prarit Bhargavad3051b42014-10-14 02:51:39 +10302001 mutex_lock(&module_mutex);
Rusty Russell944a1fa2013-04-17 13:20:03 +09302002 mod->state = MODULE_STATE_UNFORMED;
Prarit Bhargavad3051b42014-10-14 02:51:39 +10302003 mutex_unlock(&module_mutex);
Rusty Russell944a1fa2013-04-17 13:20:03 +09302004
Jason Baronb82bab4b2010-07-27 13:18:01 -07002005 /* Remove dynamic debug info */
2006 ddebug_remove_module(mod->name);
2007
Linus Torvalds1da177e2005-04-16 15:20:36 -07002008 /* Arch-specific cleanup. */
2009 module_arch_cleanup(mod);
2010
2011 /* Module unload stuff */
2012 module_unload_free(mod);
2013
Rusty Russelle180a6b2009-03-31 13:05:29 -06002014 /* Free any allocated parameters. */
2015 destroy_params(mod->kp, mod->num_kp);
2016
Rusty Russell944a1fa2013-04-17 13:20:03 +09302017 /* Now we can delete it from the lists */
2018 mutex_lock(&module_mutex);
Masami Hiramatsu461e34a2014-11-10 09:27:29 +10302019 /* Unlink carefully: kallsyms could be walking list. */
2020 list_del_rcu(&mod->list);
Peter Zijlstra93c2e102015-05-27 11:09:37 +09302021 mod_tree_remove(mod);
Masami Hiramatsu0286b5e2014-11-10 09:28:29 +10302022 /* Remove this module from bug list, this uses list_del_rcu */
Masami Hiramatsu461e34a2014-11-10 09:27:29 +10302023 module_bug_cleanup(mod);
Peter Zijlstra0be964b2015-05-27 11:09:35 +09302024 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2025 synchronize_sched();
Rusty Russell944a1fa2013-04-17 13:20:03 +09302026 mutex_unlock(&module_mutex);
2027
Linus Torvalds1da177e2005-04-16 15:20:36 -07002028 /* This may be NULL, but that's OK */
Jan Glauber01526ed2011-05-19 16:55:26 -06002029 unset_module_init_ro_nx(mod);
Rusty Russelld453cde2015-01-20 09:07:04 +10302030 module_arch_freeing_init(mod);
Rusty Russellbe1f2212015-01-20 09:07:05 +10302031 module_memfree(mod->module_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002032 kfree(mod->args);
Tejun Heo259354d2010-03-10 18:56:10 +09002033 percpu_modfree(mod);
Rusty Russell9f85a4b2010-08-05 12:59:04 -06002034
Peter Zijlstra35a93932015-02-26 16:23:11 +01002035 /* Free lock-classes; relies on the preceding sync_rcu(). */
Ingo Molnarfbb9ce952006-07-03 00:24:50 -07002036 lockdep_free_key_range(mod->module_core, mod->core_size);
2037
Linus Torvalds1da177e2005-04-16 15:20:36 -07002038 /* Finally, free the core (containing the module structure) */
Jan Glauber01526ed2011-05-19 16:55:26 -06002039 unset_module_core_ro_nx(mod);
Rusty Russellbe1f2212015-01-20 09:07:05 +10302040 module_memfree(mod->module_core);
Bernd Schmidteb8cdec2009-09-21 17:03:57 -07002041
2042#ifdef CONFIG_MPU
2043 update_protections(current->mm);
2044#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002045}
2046
2047void *__symbol_get(const char *symbol)
2048{
2049 struct module *owner;
Tim Abbott414fd312008-12-05 19:03:56 -05002050 const struct kernel_symbol *sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002051
Rusty Russell24da1cb2007-07-15 23:41:46 -07002052 preempt_disable();
Tim Abbott414fd312008-12-05 19:03:56 -05002053 sym = find_symbol(symbol, &owner, NULL, true, true);
2054 if (sym && strong_try_module_get(owner))
2055 sym = NULL;
Rusty Russell24da1cb2007-07-15 23:41:46 -07002056 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002057
Tim Abbott414fd312008-12-05 19:03:56 -05002058 return sym ? (void *)sym->value : NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002059}
2060EXPORT_SYMBOL_GPL(__symbol_get);
2061
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002062/*
2063 * Ensure that an exported symbol [global namespace] does not already exist
Robert P. J. Day02a3e592007-05-09 07:26:28 +02002064 * in the kernel or in some other module's exported symbol table.
Rusty Russellbe593f42010-06-05 11:17:37 -06002065 *
2066 * You must hold the module_mutex.
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002067 */
2068static int verify_export_symbols(struct module *mod)
2069{
Rusty Russellb2111042008-05-01 21:15:00 -05002070 unsigned int i;
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002071 struct module *owner;
Rusty Russellb2111042008-05-01 21:15:00 -05002072 const struct kernel_symbol *s;
2073 struct {
2074 const struct kernel_symbol *sym;
2075 unsigned int num;
2076 } arr[] = {
2077 { mod->syms, mod->num_syms },
2078 { mod->gpl_syms, mod->num_gpl_syms },
2079 { mod->gpl_future_syms, mod->num_gpl_future_syms },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05002080#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russellb2111042008-05-01 21:15:00 -05002081 { mod->unused_syms, mod->num_unused_syms },
2082 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05002083#endif
Rusty Russellb2111042008-05-01 21:15:00 -05002084 };
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002085
Rusty Russellb2111042008-05-01 21:15:00 -05002086 for (i = 0; i < ARRAY_SIZE(arr); i++) {
2087 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
Rusty Russellbe593f42010-06-05 11:17:37 -06002088 if (find_symbol(s->name, &owner, NULL, true, false)) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002089 pr_err("%s: exports duplicate symbol %s"
Rusty Russellb2111042008-05-01 21:15:00 -05002090 " (owned by %s)\n",
2091 mod->name, s->name, module_name(owner));
2092 return -ENOEXEC;
2093 }
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002094 }
Rusty Russellb2111042008-05-01 21:15:00 -05002095 }
2096 return 0;
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002097}
2098
Matti Linnanvuori9a4b9702007-11-08 08:37:38 -08002099/* Change all symbols so that st_value encodes the pointer directly. */
Rusty Russell49668682010-08-05 12:59:10 -06002100static int simplify_symbols(struct module *mod, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002101{
Rusty Russell49668682010-08-05 12:59:10 -06002102 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2103 Elf_Sym *sym = (void *)symsec->sh_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002104 unsigned long secbase;
Rusty Russell49668682010-08-05 12:59:10 -06002105 unsigned int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002106 int ret = 0;
Tim Abbott414fd312008-12-05 19:03:56 -05002107 const struct kernel_symbol *ksym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002108
Rusty Russell49668682010-08-05 12:59:10 -06002109 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
2110 const char *name = info->strtab + sym[i].st_name;
2111
Linus Torvalds1da177e2005-04-16 15:20:36 -07002112 switch (sym[i].st_shndx) {
2113 case SHN_COMMON:
Joe Mario80375982014-02-08 09:01:09 +01002114 /* Ignore common symbols */
2115 if (!strncmp(name, "__gnu_lto", 9))
2116 break;
2117
Linus Torvalds1da177e2005-04-16 15:20:36 -07002118 /* We compiled with -fno-common. These are not
2119 supposed to happen. */
Jim Cromie5e124162011-12-06 12:11:31 -07002120 pr_debug("Common symbol: %s\n", name);
Ionut Alexa6da0b562014-11-10 09:31:29 +10302121 pr_warn("%s: please compile with -fno-common\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002122 mod->name);
2123 ret = -ENOEXEC;
2124 break;
2125
2126 case SHN_ABS:
2127 /* Don't need to do anything */
Jim Cromie5e124162011-12-06 12:11:31 -07002128 pr_debug("Absolute symbol: 0x%08lx\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002129 (long)sym[i].st_value);
2130 break;
2131
2132 case SHN_UNDEF:
Rusty Russell49668682010-08-05 12:59:10 -06002133 ksym = resolve_symbol_wait(mod, info, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002134 /* Ok if resolved. */
Rusty Russell9bea7f22010-06-05 11:17:37 -06002135 if (ksym && !IS_ERR(ksym)) {
Tim Abbott414fd312008-12-05 19:03:56 -05002136 sym[i].st_value = ksym->value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002137 break;
Tim Abbott414fd312008-12-05 19:03:56 -05002138 }
2139
Linus Torvalds1da177e2005-04-16 15:20:36 -07002140 /* Ok if weak. */
Rusty Russell9bea7f22010-06-05 11:17:37 -06002141 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002142 break;
2143
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002144 pr_warn("%s: Unknown symbol %s (err %li)\n",
2145 mod->name, name, PTR_ERR(ksym));
Rusty Russell9bea7f22010-06-05 11:17:37 -06002146 ret = PTR_ERR(ksym) ?: -ENOENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002147 break;
2148
2149 default:
2150 /* Divert to percpu allocation if a percpu var. */
Rusty Russell49668682010-08-05 12:59:10 -06002151 if (sym[i].st_shndx == info->index.pcpu)
Tejun Heo259354d2010-03-10 18:56:10 +09002152 secbase = (unsigned long)mod_percpu(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002153 else
Rusty Russell49668682010-08-05 12:59:10 -06002154 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002155 sym[i].st_value += secbase;
2156 break;
2157 }
2158 }
2159
2160 return ret;
2161}
2162
Rusty Russell49668682010-08-05 12:59:10 -06002163static int apply_relocations(struct module *mod, const struct load_info *info)
Rusty Russell22e268e2010-08-05 12:59:05 -06002164{
2165 unsigned int i;
2166 int err = 0;
2167
2168 /* Now do relocations. */
Rusty Russell49668682010-08-05 12:59:10 -06002169 for (i = 1; i < info->hdr->e_shnum; i++) {
2170 unsigned int infosec = info->sechdrs[i].sh_info;
Rusty Russell22e268e2010-08-05 12:59:05 -06002171
2172 /* Not a valid relocation section? */
Rusty Russell49668682010-08-05 12:59:10 -06002173 if (infosec >= info->hdr->e_shnum)
Rusty Russell22e268e2010-08-05 12:59:05 -06002174 continue;
2175
2176 /* Don't bother with non-allocated sections */
Rusty Russell49668682010-08-05 12:59:10 -06002177 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
Rusty Russell22e268e2010-08-05 12:59:05 -06002178 continue;
2179
Rusty Russell49668682010-08-05 12:59:10 -06002180 if (info->sechdrs[i].sh_type == SHT_REL)
2181 err = apply_relocate(info->sechdrs, info->strtab,
2182 info->index.sym, i, mod);
2183 else if (info->sechdrs[i].sh_type == SHT_RELA)
2184 err = apply_relocate_add(info->sechdrs, info->strtab,
2185 info->index.sym, i, mod);
Rusty Russell22e268e2010-08-05 12:59:05 -06002186 if (err < 0)
2187 break;
2188 }
2189 return err;
2190}
2191
Helge Deller088af9a2008-12-31 12:31:18 +01002192/* Additional bytes needed by arch in front of individual sections */
2193unsigned int __weak arch_mod_section_prepend(struct module *mod,
2194 unsigned int section)
2195{
2196 /* default implementation just returns zero */
2197 return 0;
2198}
2199
Linus Torvalds1da177e2005-04-16 15:20:36 -07002200/* Update size with this section: return offset. */
Helge Deller088af9a2008-12-31 12:31:18 +01002201static long get_offset(struct module *mod, unsigned int *size,
2202 Elf_Shdr *sechdr, unsigned int section)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002203{
2204 long ret;
2205
Helge Deller088af9a2008-12-31 12:31:18 +01002206 *size += arch_mod_section_prepend(mod, section);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002207 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2208 *size = ret + sechdr->sh_size;
2209 return ret;
2210}
2211
2212/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2213 might -- code, read-only data, read-write data, small data. Tally
2214 sizes, and place the offsets into sh_entsize fields: high bit means it
2215 belongs in init. */
Rusty Russell49668682010-08-05 12:59:10 -06002216static void layout_sections(struct module *mod, struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002217{
2218 static unsigned long const masks[][2] = {
2219 /* NOTE: all executable code must be the first section
2220 * in this array; otherwise modify the text_size
2221 * finder in the two loops below */
2222 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2223 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
2224 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2225 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2226 };
2227 unsigned int m, i;
2228
Rusty Russell49668682010-08-05 12:59:10 -06002229 for (i = 0; i < info->hdr->e_shnum; i++)
2230 info->sechdrs[i].sh_entsize = ~0UL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002231
Jim Cromie5e124162011-12-06 12:11:31 -07002232 pr_debug("Core section allocation order:\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002233 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
Rusty Russell49668682010-08-05 12:59:10 -06002234 for (i = 0; i < info->hdr->e_shnum; ++i) {
2235 Elf_Shdr *s = &info->sechdrs[i];
2236 const char *sname = info->secstrings + s->sh_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002237
2238 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2239 || (s->sh_flags & masks[m][1])
2240 || s->sh_entsize != ~0UL
Rusty Russell49668682010-08-05 12:59:10 -06002241 || strstarts(sname, ".init"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002242 continue;
Helge Deller088af9a2008-12-31 12:31:18 +01002243 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
Jim Cromie5e124162011-12-06 12:11:31 -07002244 pr_debug("\t%s\n", sname);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002245 }
matthieu castet84e1c6b2010-11-16 22:35:16 +01002246 switch (m) {
2247 case 0: /* executable */
2248 mod->core_size = debug_align(mod->core_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002249 mod->core_text_size = mod->core_size;
matthieu castet84e1c6b2010-11-16 22:35:16 +01002250 break;
2251 case 1: /* RO: text and ro-data */
2252 mod->core_size = debug_align(mod->core_size);
2253 mod->core_ro_size = mod->core_size;
2254 break;
2255 case 3: /* whole core */
2256 mod->core_size = debug_align(mod->core_size);
2257 break;
2258 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002259 }
2260
Jim Cromie5e124162011-12-06 12:11:31 -07002261 pr_debug("Init section allocation order:\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002262 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
Rusty Russell49668682010-08-05 12:59:10 -06002263 for (i = 0; i < info->hdr->e_shnum; ++i) {
2264 Elf_Shdr *s = &info->sechdrs[i];
2265 const char *sname = info->secstrings + s->sh_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002266
2267 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2268 || (s->sh_flags & masks[m][1])
2269 || s->sh_entsize != ~0UL
Rusty Russell49668682010-08-05 12:59:10 -06002270 || !strstarts(sname, ".init"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002271 continue;
Helge Deller088af9a2008-12-31 12:31:18 +01002272 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002273 | INIT_OFFSET_MASK);
Jim Cromie5e124162011-12-06 12:11:31 -07002274 pr_debug("\t%s\n", sname);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002275 }
matthieu castet84e1c6b2010-11-16 22:35:16 +01002276 switch (m) {
2277 case 0: /* executable */
2278 mod->init_size = debug_align(mod->init_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002279 mod->init_text_size = mod->init_size;
matthieu castet84e1c6b2010-11-16 22:35:16 +01002280 break;
2281 case 1: /* RO: text and ro-data */
2282 mod->init_size = debug_align(mod->init_size);
2283 mod->init_ro_size = mod->init_size;
2284 break;
2285 case 3: /* whole init */
2286 mod->init_size = debug_align(mod->init_size);
2287 break;
2288 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002289 }
2290}
2291
Linus Torvalds1da177e2005-04-16 15:20:36 -07002292static void set_license(struct module *mod, const char *license)
2293{
2294 if (!license)
2295 license = "unspecified";
2296
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002297 if (!license_is_gpl_compatible(license)) {
Andi Kleen25ddbb12008-10-15 22:01:41 -07002298 if (!test_taint(TAINT_PROPRIETARY_MODULE))
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002299 pr_warn("%s: module license '%s' taints kernel.\n",
2300 mod->name, license);
Rusty Russell373d4d02013-01-21 17:17:39 +10302301 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2302 LOCKDEP_NOW_UNRELIABLE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002303 }
2304}
2305
2306/* Parse tag=value strings from .modinfo section */
2307static char *next_string(char *string, unsigned long *secsize)
2308{
2309 /* Skip non-zero chars */
2310 while (string[0]) {
2311 string++;
2312 if ((*secsize)-- <= 1)
2313 return NULL;
2314 }
2315
2316 /* Skip any zero padding. */
2317 while (!string[0]) {
2318 string++;
2319 if ((*secsize)-- <= 1)
2320 return NULL;
2321 }
2322 return string;
2323}
2324
Rusty Russell49668682010-08-05 12:59:10 -06002325static char *get_modinfo(struct load_info *info, const char *tag)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002326{
2327 char *p;
2328 unsigned int taglen = strlen(tag);
Rusty Russell49668682010-08-05 12:59:10 -06002329 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2330 unsigned long size = infosec->sh_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002331
Rusty Russell49668682010-08-05 12:59:10 -06002332 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002333 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2334 return p + taglen + 1;
2335 }
2336 return NULL;
2337}
2338
Rusty Russell49668682010-08-05 12:59:10 -06002339static void setup_modinfo(struct module *mod, struct load_info *info)
Matt Domschc988d2b2005-06-23 22:05:15 -07002340{
2341 struct module_attribute *attr;
2342 int i;
2343
2344 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2345 if (attr->setup)
Rusty Russell49668682010-08-05 12:59:10 -06002346 attr->setup(mod, get_modinfo(info, attr->attr.name));
Matt Domschc988d2b2005-06-23 22:05:15 -07002347 }
2348}
Matt Domschc988d2b2005-06-23 22:05:15 -07002349
Rusty Russella263f772009-09-25 00:32:58 -06002350static void free_modinfo(struct module *mod)
2351{
2352 struct module_attribute *attr;
2353 int i;
2354
2355 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2356 if (attr->free)
2357 attr->free(mod);
2358 }
2359}
2360
Linus Torvalds1da177e2005-04-16 15:20:36 -07002361#ifdef CONFIG_KALLSYMS
WANG Cong15bba372008-07-24 15:41:48 +01002362
2363/* lookup symbol in given range of kernel_symbols */
2364static const struct kernel_symbol *lookup_symbol(const char *name,
2365 const struct kernel_symbol *start,
2366 const struct kernel_symbol *stop)
2367{
Alessio Igor Bogani9d634872011-05-18 22:35:59 +02002368 return bsearch(name, start, stop - start,
2369 sizeof(struct kernel_symbol), cmp_name);
WANG Cong15bba372008-07-24 15:41:48 +01002370}
2371
Tim Abbottca4787b2009-01-05 08:40:10 -06002372static int is_exported(const char *name, unsigned long value,
2373 const struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002374{
Tim Abbottca4787b2009-01-05 08:40:10 -06002375 const struct kernel_symbol *ks;
2376 if (!mod)
2377 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
Sam Ravnborg3fd68052006-02-08 21:16:45 +01002378 else
Tim Abbottca4787b2009-01-05 08:40:10 -06002379 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2380 return ks != NULL && ks->value == value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002381}
2382
2383/* As per nm */
Rusty Russelleded41c2010-08-05 12:59:07 -06002384static char elf_type(const Elf_Sym *sym, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002385{
Rusty Russelleded41c2010-08-05 12:59:07 -06002386 const Elf_Shdr *sechdrs = info->sechdrs;
2387
Linus Torvalds1da177e2005-04-16 15:20:36 -07002388 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2389 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2390 return 'v';
2391 else
2392 return 'w';
2393 }
2394 if (sym->st_shndx == SHN_UNDEF)
2395 return 'U';
2396 if (sym->st_shndx == SHN_ABS)
2397 return 'a';
2398 if (sym->st_shndx >= SHN_LORESERVE)
2399 return '?';
2400 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2401 return 't';
2402 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2403 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2404 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2405 return 'r';
2406 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2407 return 'g';
2408 else
2409 return 'd';
2410 }
2411 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2412 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2413 return 's';
2414 else
2415 return 'b';
2416 }
Rusty Russelleded41c2010-08-05 12:59:07 -06002417 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2418 ".debug")) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002419 return 'n';
Rusty Russelleded41c2010-08-05 12:59:07 -06002420 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002421 return '?';
2422}
2423
Jan Beulich4a496222009-07-06 14:50:42 +01002424static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
Ionut Alexa6da0b562014-11-10 09:31:29 +10302425 unsigned int shnum)
Jan Beulich4a496222009-07-06 14:50:42 +01002426{
2427 const Elf_Shdr *sec;
2428
2429 if (src->st_shndx == SHN_UNDEF
2430 || src->st_shndx >= shnum
2431 || !src->st_name)
2432 return false;
2433
2434 sec = sechdrs + src->st_shndx;
2435 if (!(sec->sh_flags & SHF_ALLOC)
2436#ifndef CONFIG_KALLSYMS_ALL
2437 || !(sec->sh_flags & SHF_EXECINSTR)
2438#endif
2439 || (sec->sh_entsize & INIT_OFFSET_MASK))
2440 return false;
2441
2442 return true;
2443}
2444
Kevin Cernekee48fd1182012-01-13 09:32:14 +10302445/*
2446 * We only allocate and copy the strings needed by the parts of symtab
2447 * we keep. This is simple, but has the effect of making multiple
2448 * copies of duplicates. We could be more sophisticated, see
2449 * linux-kernel thread starting with
2450 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2451 */
Rusty Russell49668682010-08-05 12:59:10 -06002452static void layout_symtab(struct module *mod, struct load_info *info)
Jan Beulich4a496222009-07-06 14:50:42 +01002453{
Rusty Russell49668682010-08-05 12:59:10 -06002454 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2455 Elf_Shdr *strsect = info->sechdrs + info->index.str;
Jan Beulich4a496222009-07-06 14:50:42 +01002456 const Elf_Sym *src;
Satoru Takeuchi54523ec2012-12-05 12:29:04 +10302457 unsigned int i, nsrc, ndst, strtab_size = 0;
Jan Beulich4a496222009-07-06 14:50:42 +01002458
2459 /* Put symbol section at end of init part of module. */
2460 symsect->sh_flags |= SHF_ALLOC;
2461 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
Rusty Russell49668682010-08-05 12:59:10 -06002462 info->index.sym) | INIT_OFFSET_MASK;
Jim Cromie5e124162011-12-06 12:11:31 -07002463 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
Jan Beulich4a496222009-07-06 14:50:42 +01002464
Rusty Russell49668682010-08-05 12:59:10 -06002465 src = (void *)info->hdr + symsect->sh_offset;
Jan Beulich4a496222009-07-06 14:50:42 +01002466 nsrc = symsect->sh_size / sizeof(*src);
Kevin Cernekee70b1e9162011-11-12 19:08:55 -08002467
Kevin Cernekee48fd1182012-01-13 09:32:14 +10302468 /* Compute total space required for the core symbols' strtab. */
Rusty Russell59ef28b2012-10-25 10:49:25 +10302469 for (ndst = i = 0; i < nsrc; i++) {
2470 if (i == 0 ||
2471 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2472 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
Kevin Cernekee48fd1182012-01-13 09:32:14 +10302473 ndst++;
Jan Beulich554bdfe2009-07-06 14:51:44 +01002474 }
Rusty Russell59ef28b2012-10-25 10:49:25 +10302475 }
Jan Beulich4a496222009-07-06 14:50:42 +01002476
2477 /* Append room for core symbols at end of core part. */
Rusty Russell49668682010-08-05 12:59:10 -06002478 info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
Kevin Cernekee48fd1182012-01-13 09:32:14 +10302479 info->stroffs = mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
2480 mod->core_size += strtab_size;
Laura Abbott168e47f2015-02-25 14:14:57 -08002481 mod->core_size = debug_align(mod->core_size);
Jan Beulich4a496222009-07-06 14:50:42 +01002482
Jan Beulich554bdfe2009-07-06 14:51:44 +01002483 /* Put string table section at end of init part of module. */
2484 strsect->sh_flags |= SHF_ALLOC;
2485 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
Rusty Russell49668682010-08-05 12:59:10 -06002486 info->index.str) | INIT_OFFSET_MASK;
Laura Abbott168e47f2015-02-25 14:14:57 -08002487 mod->init_size = debug_align(mod->init_size);
Jim Cromie5e124162011-12-06 12:11:31 -07002488 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
Jan Beulich4a496222009-07-06 14:50:42 +01002489}
2490
Rusty Russell811d66a2010-08-05 12:59:12 -06002491static void add_kallsyms(struct module *mod, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002492{
Jan Beulich4a496222009-07-06 14:50:42 +01002493 unsigned int i, ndst;
2494 const Elf_Sym *src;
2495 Elf_Sym *dst;
Jan Beulich554bdfe2009-07-06 14:51:44 +01002496 char *s;
Rusty Russelleded41c2010-08-05 12:59:07 -06002497 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002498
Rusty Russelleded41c2010-08-05 12:59:07 -06002499 mod->symtab = (void *)symsec->sh_addr;
2500 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
Rusty Russell511ca6a2010-08-05 12:59:08 -06002501 /* Make sure we get permanent strtab: don't use info->strtab. */
2502 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002503
2504 /* Set types up while we still have access to sections. */
2505 for (i = 0; i < mod->num_symtab; i++)
Rusty Russelleded41c2010-08-05 12:59:07 -06002506 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
Jan Beulich4a496222009-07-06 14:50:42 +01002507
Rusty Russelld9131882010-08-05 12:59:08 -06002508 mod->core_symtab = dst = mod->module_core + info->symoffs;
Kevin Cernekee48fd1182012-01-13 09:32:14 +10302509 mod->core_strtab = s = mod->module_core + info->stroffs;
Jan Beulich4a496222009-07-06 14:50:42 +01002510 src = mod->symtab;
Rusty Russell59ef28b2012-10-25 10:49:25 +10302511 for (ndst = i = 0; i < mod->num_symtab; i++) {
2512 if (i == 0 ||
2513 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
2514 dst[ndst] = src[i];
2515 dst[ndst++].st_name = s - mod->core_strtab;
2516 s += strlcpy(s, &mod->strtab[src[i].st_name],
2517 KSYM_NAME_LEN) + 1;
2518 }
Jan Beulich4a496222009-07-06 14:50:42 +01002519 }
2520 mod->core_num_syms = ndst;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002521}
2522#else
Rusty Russell49668682010-08-05 12:59:10 -06002523static inline void layout_symtab(struct module *mod, struct load_info *info)
Jan Beulich4a496222009-07-06 14:50:42 +01002524{
2525}
Paul Mundt3ae91c22009-10-01 15:43:54 -07002526
Michał Mirosławabbce902010-09-20 01:58:08 +02002527static void add_kallsyms(struct module *mod, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002528{
2529}
2530#endif /* CONFIG_KALLSYMS */
2531
Jason Barone9d376f2009-02-05 11:51:38 -05002532static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
Rusty Russell5e458cc2008-10-22 10:00:13 -05002533{
Rusty Russell811d66a2010-08-05 12:59:12 -06002534 if (!debug)
2535 return;
Jason Barone9d376f2009-02-05 11:51:38 -05002536#ifdef CONFIG_DYNAMIC_DEBUG
2537 if (ddebug_add_module(debug, num, debug->modname))
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002538 pr_err("dynamic debug error adding module: %s\n",
2539 debug->modname);
Jason Barone9d376f2009-02-05 11:51:38 -05002540#endif
Rusty Russell5e458cc2008-10-22 10:00:13 -05002541}
Jason Baron346e15b2008-08-12 16:46:19 -04002542
Yehuda Sadehff49d742010-07-03 13:07:35 +10002543static void dynamic_debug_remove(struct _ddebug *debug)
2544{
2545 if (debug)
2546 ddebug_remove_module(debug->modname);
2547}
2548
Jonas Bonn74e08fc2011-06-30 21:22:11 +02002549void * __weak module_alloc(unsigned long size)
2550{
Rusty Russell82fab442012-12-11 09:38:33 +10302551 return vmalloc_exec(size);
Jonas Bonn74e08fc2011-06-30 21:22:11 +02002552}
2553
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002554#ifdef CONFIG_DEBUG_KMEMLEAK
Rusty Russell49668682010-08-05 12:59:10 -06002555static void kmemleak_load_module(const struct module *mod,
2556 const struct load_info *info)
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002557{
2558 unsigned int i;
2559
2560 /* only scan the sections containing data */
Catalin Marinasc017b4b2009-10-28 13:33:09 +00002561 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002562
Rusty Russell49668682010-08-05 12:59:10 -06002563 for (i = 1; i < info->hdr->e_shnum; i++) {
Steven Rostedt06c94942013-05-15 20:33:01 +01002564 /* Scan all writable sections that's not executable */
2565 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2566 !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2567 (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002568 continue;
2569
Rusty Russell49668682010-08-05 12:59:10 -06002570 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2571 info->sechdrs[i].sh_size, GFP_KERNEL);
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002572 }
2573}
2574#else
Rusty Russell49668682010-08-05 12:59:10 -06002575static inline void kmemleak_load_module(const struct module *mod,
2576 const struct load_info *info)
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002577{
2578}
2579#endif
2580
Rusty Russell106a4ee2012-09-26 10:09:40 +01002581#ifdef CONFIG_MODULE_SIG
Kees Cook34e11692012-10-16 07:31:07 +10302582static int module_sig_check(struct load_info *info)
Rusty Russell106a4ee2012-09-26 10:09:40 +01002583{
2584 int err = -ENOKEY;
Kees Cook34e11692012-10-16 07:31:07 +10302585 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2586 const void *mod = info->hdr;
Rusty Russell106a4ee2012-09-26 10:09:40 +01002587
Kees Cook34e11692012-10-16 07:31:07 +10302588 if (info->len > markerlen &&
2589 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
David Howellscaabe242012-10-20 01:19:29 +01002590 /* We truncate the module to discard the signature */
Kees Cook34e11692012-10-16 07:31:07 +10302591 info->len -= markerlen;
2592 err = mod_verify_sig(mod, &info->len);
Rusty Russell106a4ee2012-09-26 10:09:40 +01002593 }
2594
2595 if (!err) {
2596 info->sig_ok = true;
2597 return 0;
2598 }
2599
2600 /* Not having a signature is only an error if we're strict. */
2601 if (err == -ENOKEY && !sig_enforce)
2602 err = 0;
2603
2604 return err;
2605}
2606#else /* !CONFIG_MODULE_SIG */
Kees Cook34e11692012-10-16 07:31:07 +10302607static int module_sig_check(struct load_info *info)
Rusty Russell106a4ee2012-09-26 10:09:40 +01002608{
2609 return 0;
2610}
2611#endif /* !CONFIG_MODULE_SIG */
2612
Kees Cook34e11692012-10-16 07:31:07 +10302613/* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2614static int elf_header_check(struct load_info *info)
Rusty Russell40dd2562010-08-05 12:59:03 -06002615{
Kees Cook34e11692012-10-16 07:31:07 +10302616 if (info->len < sizeof(*(info->hdr)))
Rusty Russell40dd2562010-08-05 12:59:03 -06002617 return -ENOEXEC;
2618
Kees Cook34e11692012-10-16 07:31:07 +10302619 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2620 || info->hdr->e_type != ET_REL
2621 || !elf_check_arch(info->hdr)
2622 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2623 return -ENOEXEC;
2624
2625 if (info->hdr->e_shoff >= info->len
2626 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2627 info->len - info->hdr->e_shoff))
2628 return -ENOEXEC;
2629
2630 return 0;
2631}
2632
Linus Torvalds3afe9f82015-04-07 10:33:49 -07002633#define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2634
2635static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
2636{
2637 do {
2638 unsigned long n = min(len, COPY_CHUNK_SIZE);
2639
2640 if (copy_from_user(dst, usrc, n) != 0)
2641 return -EFAULT;
2642 cond_resched();
2643 dst += n;
2644 usrc += n;
2645 len -= n;
2646 } while (len);
2647 return 0;
2648}
2649
Kees Cook34e11692012-10-16 07:31:07 +10302650/* Sets info->hdr and info->len. */
2651static int copy_module_from_user(const void __user *umod, unsigned long len,
2652 struct load_info *info)
2653{
Kees Cook2e72d512012-10-16 07:32:07 +10302654 int err;
2655
Kees Cook34e11692012-10-16 07:31:07 +10302656 info->len = len;
2657 if (info->len < sizeof(*(info->hdr)))
Rusty Russell40dd2562010-08-05 12:59:03 -06002658 return -ENOEXEC;
2659
Kees Cook2e72d512012-10-16 07:32:07 +10302660 err = security_kernel_module_from_file(NULL);
2661 if (err)
2662 return err;
2663
Rusty Russell40dd2562010-08-05 12:59:03 -06002664 /* Suck in entire file: we'll want most of it. */
Kirill A. Shutemovcc9e6052015-03-24 12:31:40 +10302665 info->hdr = __vmalloc(info->len,
2666 GFP_KERNEL | __GFP_HIGHMEM | __GFP_NOWARN, PAGE_KERNEL);
Kees Cook34e11692012-10-16 07:31:07 +10302667 if (!info->hdr)
Rusty Russell40dd2562010-08-05 12:59:03 -06002668 return -ENOMEM;
2669
Linus Torvalds3afe9f82015-04-07 10:33:49 -07002670 if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
Kees Cook34e11692012-10-16 07:31:07 +10302671 vfree(info->hdr);
2672 return -EFAULT;
Rusty Russell40dd2562010-08-05 12:59:03 -06002673 }
2674
Rusty Russell40dd2562010-08-05 12:59:03 -06002675 return 0;
Kees Cook34e11692012-10-16 07:31:07 +10302676}
Rusty Russell40dd2562010-08-05 12:59:03 -06002677
Kees Cook34e11692012-10-16 07:31:07 +10302678/* Sets info->hdr and info->len. */
2679static int copy_module_from_fd(int fd, struct load_info *info)
2680{
Al Viroa2e05782013-08-30 12:41:41 -04002681 struct fd f = fdget(fd);
Kees Cook34e11692012-10-16 07:31:07 +10302682 int err;
2683 struct kstat stat;
2684 loff_t pos;
2685 ssize_t bytes = 0;
2686
Al Viroa2e05782013-08-30 12:41:41 -04002687 if (!f.file)
Kees Cook34e11692012-10-16 07:31:07 +10302688 return -ENOEXEC;
2689
Al Viroa2e05782013-08-30 12:41:41 -04002690 err = security_kernel_module_from_file(f.file);
Kees Cook2e72d512012-10-16 07:32:07 +10302691 if (err)
2692 goto out;
2693
Al Viroa2e05782013-08-30 12:41:41 -04002694 err = vfs_getattr(&f.file->f_path, &stat);
Kees Cook34e11692012-10-16 07:31:07 +10302695 if (err)
2696 goto out;
2697
2698 if (stat.size > INT_MAX) {
2699 err = -EFBIG;
2700 goto out;
2701 }
Sasha Levin52441fa2013-01-03 11:09:53 +10302702
2703 /* Don't hand 0 to vmalloc, it whines. */
2704 if (stat.size == 0) {
2705 err = -EINVAL;
2706 goto out;
2707 }
2708
Kees Cook34e11692012-10-16 07:31:07 +10302709 info->hdr = vmalloc(stat.size);
2710 if (!info->hdr) {
2711 err = -ENOMEM;
2712 goto out;
2713 }
2714
2715 pos = 0;
2716 while (pos < stat.size) {
Al Viroa2e05782013-08-30 12:41:41 -04002717 bytes = kernel_read(f.file, pos, (char *)(info->hdr) + pos,
Kees Cook34e11692012-10-16 07:31:07 +10302718 stat.size - pos);
2719 if (bytes < 0) {
2720 vfree(info->hdr);
2721 err = bytes;
2722 goto out;
2723 }
2724 if (bytes == 0)
2725 break;
2726 pos += bytes;
2727 }
2728 info->len = pos;
2729
2730out:
Al Viroa2e05782013-08-30 12:41:41 -04002731 fdput(f);
Rusty Russell40dd2562010-08-05 12:59:03 -06002732 return err;
2733}
2734
Rusty Russelld9131882010-08-05 12:59:08 -06002735static void free_copy(struct load_info *info)
2736{
Rusty Russelld9131882010-08-05 12:59:08 -06002737 vfree(info->hdr);
2738}
2739
Rusty Russell2f3238a2012-10-22 18:09:41 +10302740static int rewrite_section_headers(struct load_info *info, int flags)
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002741{
2742 unsigned int i;
2743
2744 /* This should always be true, but let's be sure. */
2745 info->sechdrs[0].sh_addr = 0;
2746
2747 for (i = 1; i < info->hdr->e_shnum; i++) {
2748 Elf_Shdr *shdr = &info->sechdrs[i];
2749 if (shdr->sh_type != SHT_NOBITS
2750 && info->len < shdr->sh_offset + shdr->sh_size) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002751 pr_err("Module len %lu truncated\n", info->len);
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002752 return -ENOEXEC;
2753 }
2754
2755 /* Mark all sections sh_addr with their address in the
2756 temporary image. */
2757 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2758
2759#ifndef CONFIG_MODULE_UNLOAD
2760 /* Don't load .exit sections */
2761 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2762 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2763#endif
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002764 }
Rusty Russelld6df72a2010-08-05 12:59:07 -06002765
2766 /* Track but don't keep modinfo and version sections. */
Rusty Russell2f3238a2012-10-22 18:09:41 +10302767 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2768 info->index.vers = 0; /* Pretend no __versions section! */
2769 else
2770 info->index.vers = find_sec(info, "__versions");
Rusty Russell49668682010-08-05 12:59:10 -06002771 info->index.info = find_sec(info, ".modinfo");
Rusty Russelld6df72a2010-08-05 12:59:07 -06002772 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2773 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002774 return 0;
2775}
2776
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002777/*
2778 * Set up our basic convenience variables (pointers to section headers,
2779 * search for module section index etc), and do some basic section
2780 * verification.
2781 *
2782 * Return the temporary module pointer (we'll replace it with the final
2783 * one when we move the module sections around).
2784 */
Rusty Russell2f3238a2012-10-22 18:09:41 +10302785static struct module *setup_load_info(struct load_info *info, int flags)
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002786{
2787 unsigned int i;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002788 int err;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002789 struct module *mod;
2790
2791 /* Set up the convenience variables */
2792 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002793 info->secstrings = (void *)info->hdr
2794 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002795
Rusty Russell2f3238a2012-10-22 18:09:41 +10302796 err = rewrite_section_headers(info, flags);
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002797 if (err)
2798 return ERR_PTR(err);
2799
2800 /* Find internal symbols and strings. */
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002801 for (i = 1; i < info->hdr->e_shnum; i++) {
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002802 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2803 info->index.sym = i;
2804 info->index.str = info->sechdrs[i].sh_link;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002805 info->strtab = (char *)info->hdr
2806 + info->sechdrs[info->index.str].sh_offset;
2807 break;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002808 }
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002809 }
2810
Rusty Russell49668682010-08-05 12:59:10 -06002811 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002812 if (!info->index.mod) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002813 pr_warn("No module found in object\n");
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002814 return ERR_PTR(-ENOEXEC);
2815 }
2816 /* This is temporary: point mod into copy of data. */
2817 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2818
2819 if (info->index.sym == 0) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002820 pr_warn("%s: module has no symbols (stripped?)\n", mod->name);
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002821 return ERR_PTR(-ENOEXEC);
2822 }
2823
Rusty Russell49668682010-08-05 12:59:10 -06002824 info->index.pcpu = find_pcpusec(info);
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002825
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002826 /* Check module struct version now, before we try to use module. */
2827 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2828 return ERR_PTR(-ENOEXEC);
2829
2830 return mod;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002831}
2832
Rusty Russell2f3238a2012-10-22 18:09:41 +10302833static int check_modinfo(struct module *mod, struct load_info *info, int flags)
Rusty Russell40dd2562010-08-05 12:59:03 -06002834{
Rusty Russell49668682010-08-05 12:59:10 -06002835 const char *modmagic = get_modinfo(info, "vermagic");
Rusty Russell40dd2562010-08-05 12:59:03 -06002836 int err;
2837
Rusty Russell2f3238a2012-10-22 18:09:41 +10302838 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2839 modmagic = NULL;
2840
Rusty Russell40dd2562010-08-05 12:59:03 -06002841 /* This is allowed: modprobe --force will invalidate it. */
2842 if (!modmagic) {
2843 err = try_to_force_load(mod, "bad vermagic");
2844 if (err)
2845 return err;
Rusty Russell49668682010-08-05 12:59:10 -06002846 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002847 pr_err("%s: version magic '%s' should be '%s'\n",
Rusty Russell40dd2562010-08-05 12:59:03 -06002848 mod->name, modmagic, vermagic);
2849 return -ENOEXEC;
2850 }
2851
Ben Hutchings2449b8b2011-10-24 15:12:28 +02002852 if (!get_modinfo(info, "intree"))
Rusty Russell373d4d02013-01-21 17:17:39 +10302853 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
Ben Hutchings2449b8b2011-10-24 15:12:28 +02002854
Rusty Russell49668682010-08-05 12:59:10 -06002855 if (get_modinfo(info, "staging")) {
Rusty Russell373d4d02013-01-21 17:17:39 +10302856 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002857 pr_warn("%s: module is from the staging directory, the quality "
2858 "is unknown, you have been warned.\n", mod->name);
Rusty Russell40dd2562010-08-05 12:59:03 -06002859 }
Rusty Russell22e268e2010-08-05 12:59:05 -06002860
2861 /* Set up license info based on the info section */
Rusty Russell49668682010-08-05 12:59:10 -06002862 set_license(mod, get_modinfo(info, "license"));
Rusty Russell22e268e2010-08-05 12:59:05 -06002863
Rusty Russell40dd2562010-08-05 12:59:03 -06002864 return 0;
2865}
2866
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10302867static int find_module_sections(struct module *mod, struct load_info *info)
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002868{
Rusty Russell49668682010-08-05 12:59:10 -06002869 mod->kp = section_objs(info, "__param",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002870 sizeof(*mod->kp), &mod->num_kp);
Rusty Russell49668682010-08-05 12:59:10 -06002871 mod->syms = section_objs(info, "__ksymtab",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002872 sizeof(*mod->syms), &mod->num_syms);
Rusty Russell49668682010-08-05 12:59:10 -06002873 mod->crcs = section_addr(info, "__kcrctab");
2874 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002875 sizeof(*mod->gpl_syms),
2876 &mod->num_gpl_syms);
Rusty Russell49668682010-08-05 12:59:10 -06002877 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2878 mod->gpl_future_syms = section_objs(info,
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002879 "__ksymtab_gpl_future",
2880 sizeof(*mod->gpl_future_syms),
2881 &mod->num_gpl_future_syms);
Rusty Russell49668682010-08-05 12:59:10 -06002882 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002883
2884#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russell49668682010-08-05 12:59:10 -06002885 mod->unused_syms = section_objs(info, "__ksymtab_unused",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002886 sizeof(*mod->unused_syms),
2887 &mod->num_unused_syms);
Rusty Russell49668682010-08-05 12:59:10 -06002888 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2889 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002890 sizeof(*mod->unused_gpl_syms),
2891 &mod->num_unused_gpl_syms);
Rusty Russell49668682010-08-05 12:59:10 -06002892 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002893#endif
2894#ifdef CONFIG_CONSTRUCTORS
Rusty Russell49668682010-08-05 12:59:10 -06002895 mod->ctors = section_objs(info, ".ctors",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002896 sizeof(*mod->ctors), &mod->num_ctors);
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10302897 if (!mod->ctors)
2898 mod->ctors = section_objs(info, ".init_array",
2899 sizeof(*mod->ctors), &mod->num_ctors);
2900 else if (find_sec(info, ".init_array")) {
2901 /*
2902 * This shouldn't happen with same compiler and binutils
2903 * building all parts of the module.
2904 */
Ionut Alexa6da0b562014-11-10 09:31:29 +10302905 pr_warn("%s: has both .ctors and .init_array.\n",
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10302906 mod->name);
2907 return -EINVAL;
2908 }
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002909#endif
2910
2911#ifdef CONFIG_TRACEPOINTS
Mathieu Desnoyers65498642011-01-26 17:26:22 -05002912 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2913 sizeof(*mod->tracepoints_ptrs),
2914 &mod->num_tracepoints);
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002915#endif
Jason Baronbf5438fc2010-09-17 11:09:00 -04002916#ifdef HAVE_JUMP_LABEL
2917 mod->jump_entries = section_objs(info, "__jump_table",
2918 sizeof(*mod->jump_entries),
2919 &mod->num_jump_entries);
2920#endif
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002921#ifdef CONFIG_EVENT_TRACING
Rusty Russell49668682010-08-05 12:59:10 -06002922 mod->trace_events = section_objs(info, "_ftrace_events",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002923 sizeof(*mod->trace_events),
2924 &mod->num_trace_events);
Steven Rostedt (Red Hat)3673b8e2015-03-25 15:44:21 -04002925 mod->trace_enums = section_objs(info, "_ftrace_enum_map",
2926 sizeof(*mod->trace_enums),
2927 &mod->num_trace_enums);
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002928#endif
Steven Rostedt13b9b6e2010-11-10 22:19:24 -05002929#ifdef CONFIG_TRACING
2930 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2931 sizeof(*mod->trace_bprintk_fmt_start),
2932 &mod->num_trace_bprintk_fmt);
Steven Rostedt13b9b6e2010-11-10 22:19:24 -05002933#endif
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002934#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2935 /* sechdrs[0].sh_size is always zero */
Rusty Russell49668682010-08-05 12:59:10 -06002936 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002937 sizeof(*mod->ftrace_callsites),
2938 &mod->num_ftrace_callsites);
2939#endif
Rusty Russell22e268e2010-08-05 12:59:05 -06002940
Rusty Russell811d66a2010-08-05 12:59:12 -06002941 mod->extable = section_objs(info, "__ex_table",
2942 sizeof(*mod->extable), &mod->num_exentries);
2943
Rusty Russell49668682010-08-05 12:59:10 -06002944 if (section_addr(info, "__obsparm"))
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002945 pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
Rusty Russell811d66a2010-08-05 12:59:12 -06002946
2947 info->debug = section_objs(info, "__verbose",
2948 sizeof(*info->debug), &info->num_debug);
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10302949
2950 return 0;
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002951}
2952
Rusty Russell49668682010-08-05 12:59:10 -06002953static int move_module(struct module *mod, struct load_info *info)
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002954{
2955 int i;
2956 void *ptr;
2957
2958 /* Do the allocs. */
Peter Zijlstra4f6665462015-05-27 11:09:38 +09302959 ptr = module_alloc(mod->core_size);
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002960 /*
2961 * The pointer to this block is stored in the module structure
2962 * which is inside the block. Just mark it as not being a
2963 * leak.
2964 */
2965 kmemleak_not_leak(ptr);
2966 if (!ptr)
Rusty Russelld9131882010-08-05 12:59:08 -06002967 return -ENOMEM;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002968
2969 memset(ptr, 0, mod->core_size);
2970 mod->module_core = ptr;
2971
Rusty Russell82fab442012-12-11 09:38:33 +10302972 if (mod->init_size) {
Peter Zijlstra4f6665462015-05-27 11:09:38 +09302973 ptr = module_alloc(mod->init_size);
Rusty Russell82fab442012-12-11 09:38:33 +10302974 /*
2975 * The pointer to this block is stored in the module structure
2976 * which is inside the block. This block doesn't need to be
2977 * scanned as it contains data and code that will be freed
2978 * after the module is initialized.
2979 */
2980 kmemleak_ignore(ptr);
2981 if (!ptr) {
Rusty Russellbe1f2212015-01-20 09:07:05 +10302982 module_memfree(mod->module_core);
Rusty Russell82fab442012-12-11 09:38:33 +10302983 return -ENOMEM;
2984 }
2985 memset(ptr, 0, mod->init_size);
2986 mod->module_init = ptr;
2987 } else
2988 mod->module_init = NULL;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002989
2990 /* Transfer each section which specifies SHF_ALLOC */
Jim Cromie5e124162011-12-06 12:11:31 -07002991 pr_debug("final section addresses:\n");
Rusty Russell49668682010-08-05 12:59:10 -06002992 for (i = 0; i < info->hdr->e_shnum; i++) {
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002993 void *dest;
Rusty Russell49668682010-08-05 12:59:10 -06002994 Elf_Shdr *shdr = &info->sechdrs[i];
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002995
Rusty Russell49668682010-08-05 12:59:10 -06002996 if (!(shdr->sh_flags & SHF_ALLOC))
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002997 continue;
2998
Rusty Russell49668682010-08-05 12:59:10 -06002999 if (shdr->sh_entsize & INIT_OFFSET_MASK)
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003000 dest = mod->module_init
Rusty Russell49668682010-08-05 12:59:10 -06003001 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003002 else
Rusty Russell49668682010-08-05 12:59:10 -06003003 dest = mod->module_core + shdr->sh_entsize;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003004
Rusty Russell49668682010-08-05 12:59:10 -06003005 if (shdr->sh_type != SHT_NOBITS)
3006 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003007 /* Update sh_addr to point to copy in image. */
Rusty Russell49668682010-08-05 12:59:10 -06003008 shdr->sh_addr = (unsigned long)dest;
Jim Cromie5e124162011-12-06 12:11:31 -07003009 pr_debug("\t0x%lx %s\n",
3010 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003011 }
Rusty Russelld9131882010-08-05 12:59:08 -06003012
3013 return 0;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003014}
3015
Rusty Russell49668682010-08-05 12:59:10 -06003016static int check_module_license_and_versions(struct module *mod)
Rusty Russell22e268e2010-08-05 12:59:05 -06003017{
3018 /*
3019 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3020 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3021 * using GPL-only symbols it needs.
3022 */
3023 if (strcmp(mod->name, "ndiswrapper") == 0)
Rusty Russell373d4d02013-01-21 17:17:39 +10303024 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
Rusty Russell22e268e2010-08-05 12:59:05 -06003025
3026 /* driverloader was caught wrongly pretending to be under GPL */
3027 if (strcmp(mod->name, "driverloader") == 0)
Rusty Russell373d4d02013-01-21 17:17:39 +10303028 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3029 LOCKDEP_NOW_UNRELIABLE);
Rusty Russell22e268e2010-08-05 12:59:05 -06003030
Matthew Garrettc99af372012-06-22 13:49:31 -04003031 /* lve claims to be GPL but upstream won't provide source */
3032 if (strcmp(mod->name, "lve") == 0)
Rusty Russell373d4d02013-01-21 17:17:39 +10303033 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3034 LOCKDEP_NOW_UNRELIABLE);
Matthew Garrettc99af372012-06-22 13:49:31 -04003035
Rusty Russell22e268e2010-08-05 12:59:05 -06003036#ifdef CONFIG_MODVERSIONS
3037 if ((mod->num_syms && !mod->crcs)
3038 || (mod->num_gpl_syms && !mod->gpl_crcs)
3039 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
3040#ifdef CONFIG_UNUSED_SYMBOLS
3041 || (mod->num_unused_syms && !mod->unused_crcs)
3042 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
3043#endif
3044 ) {
3045 return try_to_force_load(mod,
3046 "no versions for exported symbols");
3047 }
3048#endif
3049 return 0;
3050}
3051
3052static void flush_module_icache(const struct module *mod)
3053{
3054 mm_segment_t old_fs;
3055
3056 /* flush the icache in correct context */
3057 old_fs = get_fs();
3058 set_fs(KERNEL_DS);
3059
3060 /*
3061 * Flush the instruction cache, since we've played with text.
3062 * Do it before processing of module parameters, so the module
3063 * can provide parameter accessor functions of its own.
3064 */
3065 if (mod->module_init)
3066 flush_icache_range((unsigned long)mod->module_init,
3067 (unsigned long)mod->module_init
3068 + mod->init_size);
3069 flush_icache_range((unsigned long)mod->module_core,
3070 (unsigned long)mod->module_core + mod->core_size);
3071
3072 set_fs(old_fs);
3073}
3074
Jonas Bonn74e08fc2011-06-30 21:22:11 +02003075int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
3076 Elf_Shdr *sechdrs,
3077 char *secstrings,
3078 struct module *mod)
3079{
3080 return 0;
3081}
3082
Rusty Russell2f3238a2012-10-22 18:09:41 +10303083static struct module *layout_and_allocate(struct load_info *info, int flags)
Rusty Russelld9131882010-08-05 12:59:08 -06003084{
3085 /* Module within temporary copy. */
3086 struct module *mod;
3087 int err;
3088
Rusty Russell2f3238a2012-10-22 18:09:41 +10303089 mod = setup_load_info(info, flags);
Rusty Russelld9131882010-08-05 12:59:08 -06003090 if (IS_ERR(mod))
3091 return mod;
3092
Rusty Russell2f3238a2012-10-22 18:09:41 +10303093 err = check_modinfo(mod, info, flags);
Rusty Russelld9131882010-08-05 12:59:08 -06003094 if (err)
3095 return ERR_PTR(err);
3096
3097 /* Allow arches to frob section contents and sizes. */
Rusty Russell49668682010-08-05 12:59:10 -06003098 err = module_frob_arch_sections(info->hdr, info->sechdrs,
3099 info->secstrings, mod);
Rusty Russelld9131882010-08-05 12:59:08 -06003100 if (err < 0)
Rusty Russell8d8022e2013-07-03 10:06:28 +09303101 return ERR_PTR(err);
Rusty Russelld9131882010-08-05 12:59:08 -06003102
Rusty Russell8d8022e2013-07-03 10:06:28 +09303103 /* We will do a special allocation for per-cpu sections later. */
3104 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
Rusty Russelld9131882010-08-05 12:59:08 -06003105
3106 /* Determine total sizes, and put offsets in sh_entsize. For now
3107 this is done generically; there doesn't appear to be any
3108 special cases for the architectures. */
Rusty Russell49668682010-08-05 12:59:10 -06003109 layout_sections(mod, info);
Rusty Russell49668682010-08-05 12:59:10 -06003110 layout_symtab(mod, info);
Rusty Russelld9131882010-08-05 12:59:08 -06003111
3112 /* Allocate and move to the final place */
Rusty Russell49668682010-08-05 12:59:10 -06003113 err = move_module(mod, info);
Rusty Russelld9131882010-08-05 12:59:08 -06003114 if (err)
Rusty Russell8d8022e2013-07-03 10:06:28 +09303115 return ERR_PTR(err);
Rusty Russelld9131882010-08-05 12:59:08 -06003116
3117 /* Module has been copied to its final place now: return it. */
3118 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
Rusty Russell49668682010-08-05 12:59:10 -06003119 kmemleak_load_module(mod, info);
Rusty Russelld9131882010-08-05 12:59:08 -06003120 return mod;
Rusty Russelld9131882010-08-05 12:59:08 -06003121}
3122
3123/* mod is no longer valid after this! */
3124static void module_deallocate(struct module *mod, struct load_info *info)
3125{
Rusty Russelld9131882010-08-05 12:59:08 -06003126 percpu_modfree(mod);
Rusty Russelld453cde2015-01-20 09:07:04 +10303127 module_arch_freeing_init(mod);
Rusty Russellbe1f2212015-01-20 09:07:05 +10303128 module_memfree(mod->module_init);
3129 module_memfree(mod->module_core);
Rusty Russelld9131882010-08-05 12:59:08 -06003130}
3131
Jonas Bonn74e08fc2011-06-30 21:22:11 +02003132int __weak module_finalize(const Elf_Ehdr *hdr,
3133 const Elf_Shdr *sechdrs,
3134 struct module *me)
3135{
3136 return 0;
3137}
3138
Rusty Russell811d66a2010-08-05 12:59:12 -06003139static int post_relocation(struct module *mod, const struct load_info *info)
3140{
Rusty Russell51f3d0f2010-08-05 12:59:13 -06003141 /* Sort exception table now relocations are done. */
Rusty Russell811d66a2010-08-05 12:59:12 -06003142 sort_extable(mod->extable, mod->extable + mod->num_exentries);
3143
3144 /* Copy relocated percpu area over. */
3145 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3146 info->sechdrs[info->index.pcpu].sh_size);
3147
Rusty Russell51f3d0f2010-08-05 12:59:13 -06003148 /* Setup kallsyms-specific fields. */
Rusty Russell811d66a2010-08-05 12:59:12 -06003149 add_kallsyms(mod, info);
3150
3151 /* Arch-specific module finalizing. */
3152 return module_finalize(info->hdr, info->sechdrs, mod);
3153}
3154
Rusty Russell9bb9c3b2012-09-28 14:31:03 +09303155/* Is this module of this name done loading? No locks held. */
3156static bool finished_loading(const char *name)
3157{
3158 struct module *mod;
3159 bool ret;
3160
Peter Zijlstra9cc019b2015-02-11 15:01:13 +10303161 /*
3162 * The module_mutex should not be a heavily contended lock;
3163 * if we get the occasional sleep here, we'll go an extra iteration
3164 * in the wait_event_interruptible(), which is harmless.
3165 */
3166 sched_annotate_sleep();
Rusty Russell9bb9c3b2012-09-28 14:31:03 +09303167 mutex_lock(&module_mutex);
Mathias Krause4f6de4d2013-07-02 15:35:11 +09303168 mod = find_module_all(name, strlen(name), true);
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303169 ret = !mod || mod->state == MODULE_STATE_LIVE
3170 || mod->state == MODULE_STATE_GOING;
Rusty Russell9bb9c3b2012-09-28 14:31:03 +09303171 mutex_unlock(&module_mutex);
3172
3173 return ret;
3174}
3175
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -07003176/* Call module constructors. */
3177static void do_mod_ctors(struct module *mod)
3178{
3179#ifdef CONFIG_CONSTRUCTORS
3180 unsigned long i;
3181
3182 for (i = 0; i < mod->num_ctors; i++)
3183 mod->ctors[i]();
3184#endif
3185}
3186
Rusty Russellc7496372015-01-20 09:07:05 +10303187/* For freeing module_init on success, in case kallsyms traversing */
3188struct mod_initfree {
3189 struct rcu_head rcu;
3190 void *module_init;
3191};
3192
3193static void do_free_init(struct rcu_head *head)
3194{
3195 struct mod_initfree *m = container_of(head, struct mod_initfree, rcu);
3196 module_memfree(m->module_init);
3197 kfree(m);
3198}
3199
Jan Kiszkabe02a182015-02-17 13:46:50 -08003200/*
3201 * This is where the real work happens.
3202 *
3203 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3204 * helper command 'lx-symbols'.
3205 */
3206static noinline int do_init_module(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003207{
Linus Torvalds1da177e2005-04-16 15:20:36 -07003208 int ret = 0;
Rusty Russellc7496372015-01-20 09:07:05 +10303209 struct mod_initfree *freeinit;
3210
3211 freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
3212 if (!freeinit) {
3213 ret = -ENOMEM;
3214 goto fail;
3215 }
3216 freeinit->module_init = mod->module_init;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003217
Tejun Heo774a1222013-01-15 18:52:51 -08003218 /*
3219 * We want to find out whether @mod uses async during init. Clear
3220 * PF_USED_ASYNC. async_schedule*() will set it.
3221 */
3222 current->flags &= ~PF_USED_ASYNC;
3223
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -07003224 do_mod_ctors(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003225 /* Start the module */
3226 if (mod->init != NULL)
Arjan van de Ven59f94152008-07-30 12:49:02 -07003227 ret = do_one_initcall(mod->init);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003228 if (ret < 0) {
Rusty Russellc7496372015-01-20 09:07:05 +10303229 goto fail_free_freeinit;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003230 }
Alexey Dobriyane24e2e62008-03-10 11:43:53 -07003231 if (ret > 0) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003232 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3233 "follow 0/-E convention\n"
3234 "%s: loading module anyway...\n",
3235 __func__, mod->name, ret, __func__);
Alexey Dobriyane24e2e62008-03-10 11:43:53 -07003236 dump_stack();
3237 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003238
Rusty Russell6f139092012-09-28 14:31:03 +09303239 /* Now it's a first class citizen! */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003240 mod->state = MODULE_STATE_LIVE;
Masami Hiramatsu0deddf432009-01-06 14:41:54 -08003241 blocking_notifier_call_chain(&module_notify_list,
3242 MODULE_STATE_LIVE, mod);
Rusty Russell6c5db222008-03-10 11:43:52 -07003243
Tejun Heo774a1222013-01-15 18:52:51 -08003244 /*
3245 * We need to finish all async code before the module init sequence
3246 * is done. This has potential to deadlock. For example, a newly
3247 * detected block device can trigger request_module() of the
3248 * default iosched from async probing task. Once userland helper
3249 * reaches here, async_synchronize_full() will wait on the async
3250 * task waiting on request_module() and deadlock.
3251 *
3252 * This deadlock is avoided by perfomring async_synchronize_full()
3253 * iff module init queued any async jobs. This isn't a full
3254 * solution as it will deadlock the same if module loading from
3255 * async jobs nests more than once; however, due to the various
3256 * constraints, this hack seems to be the best option for now.
3257 * Please refer to the following thread for details.
3258 *
3259 * http://thread.gmane.org/gmane.linux.kernel/1420814
3260 */
Luis R. Rodriguezf2411da2015-03-30 16:20:05 -07003261 if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC))
Tejun Heo774a1222013-01-15 18:52:51 -08003262 async_synchronize_full();
Linus Torvaldsd6de2c82009-04-10 12:17:41 -07003263
Rusty Russell6c5db222008-03-10 11:43:52 -07003264 mutex_lock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003265 /* Drop initial reference. */
3266 module_put(mod);
Rusty Russellad6561d2009-06-12 21:47:03 -06003267 trim_init_extable(mod);
Jan Beulich4a496222009-07-06 14:50:42 +01003268#ifdef CONFIG_KALLSYMS
3269 mod->num_symtab = mod->core_num_syms;
3270 mod->symtab = mod->core_symtab;
Jan Beulich554bdfe2009-07-06 14:51:44 +01003271 mod->strtab = mod->core_strtab;
Jan Beulich4a496222009-07-06 14:50:42 +01003272#endif
Peter Zijlstra93c2e102015-05-27 11:09:37 +09303273 mod_tree_remove_init(mod);
Jan Glauber01526ed2011-05-19 16:55:26 -06003274 unset_module_init_ro_nx(mod);
Rusty Russelld453cde2015-01-20 09:07:04 +10303275 module_arch_freeing_init(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003276 mod->module_init = NULL;
3277 mod->init_size = 0;
Jan Glauber4d103802011-05-19 16:55:25 -06003278 mod->init_ro_size = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003279 mod->init_text_size = 0;
Rusty Russellc7496372015-01-20 09:07:05 +10303280 /*
3281 * We want to free module_init, but be aware that kallsyms may be
Peter Zijlstra0be964b2015-05-27 11:09:35 +09303282 * walking this with preempt disabled. In all the failure paths, we
3283 * call synchronize_sched(), but we don't want to slow down the success
3284 * path, so use actual RCU here.
Rusty Russellc7496372015-01-20 09:07:05 +10303285 */
Peter Zijlstra0be964b2015-05-27 11:09:35 +09303286 call_rcu_sched(&freeinit->rcu, do_free_init);
Ashutosh Naik6389a382006-03-23 03:00:46 -08003287 mutex_unlock(&module_mutex);
Rusty Russell6f139092012-09-28 14:31:03 +09303288 wake_up_all(&module_wq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003289
3290 return 0;
Rusty Russellc7496372015-01-20 09:07:05 +10303291
3292fail_free_freeinit:
3293 kfree(freeinit);
3294fail:
3295 /* Try to protect us from buggy refcounters. */
3296 mod->state = MODULE_STATE_GOING;
3297 synchronize_sched();
3298 module_put(mod);
3299 blocking_notifier_call_chain(&module_notify_list,
3300 MODULE_STATE_GOING, mod);
3301 free_module(mod);
3302 wake_up_all(&module_wq);
3303 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003304}
3305
Kees Cook34e11692012-10-16 07:31:07 +10303306static int may_init_module(void)
3307{
3308 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3309 return -EPERM;
3310
3311 return 0;
3312}
3313
Rusty Russella3535c72013-01-21 17:18:59 +10303314/*
3315 * We try to place it in the list now to make sure it's unique before
3316 * we dedicate too many resources. In particular, temporary percpu
3317 * memory exhaustion.
3318 */
3319static int add_unformed_module(struct module *mod)
3320{
3321 int err;
3322 struct module *old;
3323
3324 mod->state = MODULE_STATE_UNFORMED;
3325
3326again:
3327 mutex_lock(&module_mutex);
Mathias Krause4f6de4d2013-07-02 15:35:11 +09303328 old = find_module_all(mod->name, strlen(mod->name), true);
3329 if (old != NULL) {
Rusty Russella3535c72013-01-21 17:18:59 +10303330 if (old->state == MODULE_STATE_COMING
3331 || old->state == MODULE_STATE_UNFORMED) {
3332 /* Wait in case it fails to load. */
3333 mutex_unlock(&module_mutex);
Peter Zijlstra9cc019b2015-02-11 15:01:13 +10303334 err = wait_event_interruptible(module_wq,
3335 finished_loading(mod->name));
Rusty Russella3535c72013-01-21 17:18:59 +10303336 if (err)
3337 goto out_unlocked;
3338 goto again;
3339 }
3340 err = -EEXIST;
3341 goto out;
3342 }
Peter Zijlstra4f6665462015-05-27 11:09:38 +09303343 mod_update_bounds(mod);
Rusty Russella3535c72013-01-21 17:18:59 +10303344 list_add_rcu(&mod->list, &modules);
Peter Zijlstra93c2e102015-05-27 11:09:37 +09303345 mod_tree_insert(mod);
Rusty Russella3535c72013-01-21 17:18:59 +10303346 err = 0;
3347
3348out:
3349 mutex_unlock(&module_mutex);
3350out_unlocked:
3351 return err;
3352}
3353
3354static int complete_formation(struct module *mod, struct load_info *info)
3355{
3356 int err;
3357
3358 mutex_lock(&module_mutex);
3359
3360 /* Find duplicate symbols (must be called under lock). */
3361 err = verify_export_symbols(mod);
3362 if (err < 0)
3363 goto out;
3364
3365 /* This relies on module_mutex for list integrity. */
3366 module_bug_finalize(info->hdr, info->sechdrs, mod);
3367
Rusty Russell49822232014-05-14 10:54:19 +09303368 /* Set RO and NX regions for core */
3369 set_section_ro_nx(mod->module_core,
3370 mod->core_text_size,
3371 mod->core_ro_size,
3372 mod->core_size);
3373
3374 /* Set RO and NX regions for init */
3375 set_section_ro_nx(mod->module_init,
3376 mod->init_text_size,
3377 mod->init_ro_size,
3378 mod->init_size);
3379
Rusty Russella3535c72013-01-21 17:18:59 +10303380 /* Mark state as coming so strong_try_module_get() ignores us,
3381 * but kallsyms etc. can see us. */
3382 mod->state = MODULE_STATE_COMING;
Rusty Russell49822232014-05-14 10:54:19 +09303383 mutex_unlock(&module_mutex);
3384
3385 blocking_notifier_call_chain(&module_notify_list,
3386 MODULE_STATE_COMING, mod);
3387 return 0;
Rusty Russella3535c72013-01-21 17:18:59 +10303388
3389out:
3390 mutex_unlock(&module_mutex);
3391 return err;
3392}
3393
Luis R. Rodriguezecc86172015-03-30 16:20:03 -07003394static int unknown_module_param_cb(char *param, char *val, const char *modname,
3395 void *arg)
Rusty Russell54041d82013-07-02 15:35:12 +09303396{
Luis R. Rodriguezf2411da2015-03-30 16:20:05 -07003397 struct module *mod = arg;
3398 int ret;
3399
3400 if (strcmp(param, "async_probe") == 0) {
3401 mod->async_probe_requested = true;
3402 return 0;
3403 }
3404
Ionut Alexa6da0b562014-11-10 09:31:29 +10303405 /* Check for magic 'dyndbg' arg */
Luis R. Rodriguezf2411da2015-03-30 16:20:05 -07003406 ret = ddebug_dyndbg_module_param_cb(param, val, modname);
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003407 if (ret != 0)
3408 pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
Rusty Russell54041d82013-07-02 15:35:12 +09303409 return 0;
3410}
3411
Kees Cook34e11692012-10-16 07:31:07 +10303412/* Allocate and load the module: note that size of section 0 is always
3413 zero, and we rely on this for optional sections. */
Rusty Russell2f3238a2012-10-22 18:09:41 +10303414static int load_module(struct load_info *info, const char __user *uargs,
3415 int flags)
Kees Cook34e11692012-10-16 07:31:07 +10303416{
Rusty Russella3535c72013-01-21 17:18:59 +10303417 struct module *mod;
Kees Cook34e11692012-10-16 07:31:07 +10303418 long err;
Rusty Russell51e158c2014-04-28 11:34:33 +09303419 char *after_dashes;
Kees Cook34e11692012-10-16 07:31:07 +10303420
3421 err = module_sig_check(info);
3422 if (err)
3423 goto free_copy;
3424
3425 err = elf_header_check(info);
3426 if (err)
3427 goto free_copy;
3428
3429 /* Figure out module layout, and allocate all the memory. */
Rusty Russell2f3238a2012-10-22 18:09:41 +10303430 mod = layout_and_allocate(info, flags);
Kees Cook34e11692012-10-16 07:31:07 +10303431 if (IS_ERR(mod)) {
3432 err = PTR_ERR(mod);
3433 goto free_copy;
3434 }
3435
Rusty Russella3535c72013-01-21 17:18:59 +10303436 /* Reserve our place in the list. */
3437 err = add_unformed_module(mod);
3438 if (err)
Rusty Russell1fb93412013-01-12 13:27:34 +10303439 goto free_module;
Rusty Russell1fb93412013-01-12 13:27:34 +10303440
Kees Cook34e11692012-10-16 07:31:07 +10303441#ifdef CONFIG_MODULE_SIG
3442 mod->sig_ok = info->sig_ok;
Rusty Russell64748a22013-01-21 17:03:02 +10303443 if (!mod->sig_ok) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003444 pr_notice_once("%s: module verification failed: signature "
Marcel Holtmannab92ebb2015-02-06 15:09:57 +10303445 "and/or required key missing - tainting "
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003446 "kernel\n", mod->name);
Mathieu Desnoyers66cc69e2014-03-13 12:11:30 +10303447 add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
Rusty Russell64748a22013-01-21 17:03:02 +10303448 }
Kees Cook34e11692012-10-16 07:31:07 +10303449#endif
3450
Rusty Russell8d8022e2013-07-03 10:06:28 +09303451 /* To avoid stressing percpu allocator, do this once we're unique. */
Rusty Russell9eb76d72013-07-03 10:06:29 +09303452 err = percpu_modalloc(mod, info);
Rusty Russell8d8022e2013-07-03 10:06:28 +09303453 if (err)
3454 goto unlink_mod;
3455
Kees Cook34e11692012-10-16 07:31:07 +10303456 /* Now module is in final location, initialize linked lists, etc. */
3457 err = module_unload_init(mod);
3458 if (err)
Rusty Russell1fb93412013-01-12 13:27:34 +10303459 goto unlink_mod;
Kees Cook34e11692012-10-16 07:31:07 +10303460
Rusty Russellcf2fde72015-06-26 06:44:38 +09303461 init_param_lock(mod);
Dan Streetmanb51d23e2015-06-17 06:18:52 +09303462
Kees Cook34e11692012-10-16 07:31:07 +10303463 /* Now we've got everything in the final locations, we can
3464 * find optional sections. */
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10303465 err = find_module_sections(mod, info);
3466 if (err)
3467 goto free_unload;
Kees Cook34e11692012-10-16 07:31:07 +10303468
3469 err = check_module_license_and_versions(mod);
3470 if (err)
3471 goto free_unload;
3472
3473 /* Set up MODINFO_ATTR fields */
3474 setup_modinfo(mod, info);
3475
3476 /* Fix up syms, so that st_value is a pointer to location. */
3477 err = simplify_symbols(mod, info);
3478 if (err < 0)
3479 goto free_modinfo;
3480
3481 err = apply_relocations(mod, info);
3482 if (err < 0)
3483 goto free_modinfo;
3484
3485 err = post_relocation(mod, info);
3486 if (err < 0)
3487 goto free_modinfo;
3488
3489 flush_module_icache(mod);
3490
3491 /* Now copy in args */
3492 mod->args = strndup_user(uargs, ~0UL >> 1);
3493 if (IS_ERR(mod->args)) {
3494 err = PTR_ERR(mod->args);
3495 goto free_arch_cleanup;
3496 }
3497
Kees Cook34e11692012-10-16 07:31:07 +10303498 dynamic_debug_setup(info->debug, info->num_debug);
3499
Steven Rostedt (Red Hat)a949ae52014-04-24 10:40:12 -04003500 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3501 ftrace_module_init(mod);
3502
Rusty Russella3535c72013-01-21 17:18:59 +10303503 /* Finally it's fully formed, ready to start executing. */
3504 err = complete_formation(mod, info);
3505 if (err)
Rusty Russell1fb93412013-01-12 13:27:34 +10303506 goto ddebug_cleanup;
Kees Cook34e11692012-10-16 07:31:07 +10303507
Kees Cook34e11692012-10-16 07:31:07 +10303508 /* Module is ready to execute: parsing args may do that. */
Rusty Russell51e158c2014-04-28 11:34:33 +09303509 after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
Luis R. Rodriguezecc86172015-03-30 16:20:03 -07003510 -32768, 32767, NULL,
3511 unknown_module_param_cb);
Rusty Russell51e158c2014-04-28 11:34:33 +09303512 if (IS_ERR(after_dashes)) {
3513 err = PTR_ERR(after_dashes);
Rusty Russell1fb93412013-01-12 13:27:34 +10303514 goto bug_cleanup;
Rusty Russell51e158c2014-04-28 11:34:33 +09303515 } else if (after_dashes) {
3516 pr_warn("%s: parameters '%s' after `--' ignored\n",
3517 mod->name, after_dashes);
3518 }
Kees Cook34e11692012-10-16 07:31:07 +10303519
3520 /* Link in to syfs. */
3521 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3522 if (err < 0)
Rusty Russell1fb93412013-01-12 13:27:34 +10303523 goto bug_cleanup;
Kees Cook34e11692012-10-16 07:31:07 +10303524
3525 /* Get rid of temporary copy. */
3526 free_copy(info);
3527
3528 /* Done! */
3529 trace_module_load(mod);
3530
3531 return do_init_module(mod);
3532
Rusty Russell1fb93412013-01-12 13:27:34 +10303533 bug_cleanup:
3534 /* module_bug_cleanup needs module_mutex protection */
Kees Cook34e11692012-10-16 07:31:07 +10303535 mutex_lock(&module_mutex);
Kees Cook34e11692012-10-16 07:31:07 +10303536 module_bug_cleanup(mod);
Linus Torvaldsee61abb2013-01-20 20:22:58 -08003537 mutex_unlock(&module_mutex);
Andy Lutomirskiff7e0052014-08-16 04:13:37 +09303538
Steven Rostedt37815bf2015-05-09 03:06:23 +09303539 blocking_notifier_call_chain(&module_notify_list,
3540 MODULE_STATE_GOING, mod);
3541
Andy Lutomirskiff7e0052014-08-16 04:13:37 +09303542 /* we can't deallocate the module until we clear memory protection */
3543 unset_module_init_ro_nx(mod);
3544 unset_module_core_ro_nx(mod);
3545
Rusty Russella3535c72013-01-21 17:18:59 +10303546 ddebug_cleanup:
Rusty Russell1fb93412013-01-12 13:27:34 +10303547 dynamic_debug_remove(info->debug);
Kees Cook34e11692012-10-16 07:31:07 +10303548 synchronize_sched();
3549 kfree(mod->args);
3550 free_arch_cleanup:
3551 module_arch_cleanup(mod);
3552 free_modinfo:
3553 free_modinfo(mod);
3554 free_unload:
3555 module_unload_free(mod);
Rusty Russell1fb93412013-01-12 13:27:34 +10303556 unlink_mod:
3557 mutex_lock(&module_mutex);
3558 /* Unlink carefully: kallsyms could be walking list. */
3559 list_del_rcu(&mod->list);
Peter Zijlstra758556b2015-07-09 06:48:06 +09303560 mod_tree_remove(mod);
Rusty Russell1fb93412013-01-12 13:27:34 +10303561 wake_up_all(&module_wq);
Peter Zijlstra0be964b2015-05-27 11:09:35 +09303562 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3563 synchronize_sched();
Rusty Russell1fb93412013-01-12 13:27:34 +10303564 mutex_unlock(&module_mutex);
Kees Cook34e11692012-10-16 07:31:07 +10303565 free_module:
Peter Zijlstra35a93932015-02-26 16:23:11 +01003566 /* Free lock-classes; relies on the preceding sync_rcu() */
3567 lockdep_free_key_range(mod->module_core, mod->core_size);
3568
Kees Cook34e11692012-10-16 07:31:07 +10303569 module_deallocate(mod, info);
3570 free_copy:
3571 free_copy(info);
3572 return err;
3573}
3574
3575SYSCALL_DEFINE3(init_module, void __user *, umod,
3576 unsigned long, len, const char __user *, uargs)
3577{
3578 int err;
3579 struct load_info info = { };
3580
3581 err = may_init_module();
3582 if (err)
3583 return err;
3584
3585 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3586 umod, len, uargs);
3587
3588 err = copy_module_from_user(umod, len, &info);
3589 if (err)
3590 return err;
3591
Rusty Russell2f3238a2012-10-22 18:09:41 +10303592 return load_module(&info, uargs, 0);
Kees Cook34e11692012-10-16 07:31:07 +10303593}
3594
Rusty Russell2f3238a2012-10-22 18:09:41 +10303595SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
Kees Cook34e11692012-10-16 07:31:07 +10303596{
3597 int err;
3598 struct load_info info = { };
3599
3600 err = may_init_module();
3601 if (err)
3602 return err;
3603
Rusty Russell2f3238a2012-10-22 18:09:41 +10303604 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3605
3606 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3607 |MODULE_INIT_IGNORE_VERMAGIC))
3608 return -EINVAL;
Kees Cook34e11692012-10-16 07:31:07 +10303609
3610 err = copy_module_from_fd(fd, &info);
3611 if (err)
3612 return err;
3613
Rusty Russell2f3238a2012-10-22 18:09:41 +10303614 return load_module(&info, uargs, flags);
Kees Cook34e11692012-10-16 07:31:07 +10303615}
3616
Linus Torvalds1da177e2005-04-16 15:20:36 -07003617static inline int within(unsigned long addr, void *start, unsigned long size)
3618{
3619 return ((void *)addr >= start && (void *)addr < start + size);
3620}
3621
3622#ifdef CONFIG_KALLSYMS
3623/*
3624 * This ignores the intensely annoying "mapping symbols" found
3625 * in ARM ELF files: $a, $t and $d.
3626 */
3627static inline int is_arm_mapping_symbol(const char *str)
3628{
Russell King2e3a10a2014-07-27 07:29:01 +09303629 if (str[0] == '.' && str[1] == 'L')
3630 return true;
Kyle McMartin6c34f1f2014-09-16 22:37:18 +01003631 return str[0] == '$' && strchr("axtd", str[1])
Linus Torvalds1da177e2005-04-16 15:20:36 -07003632 && (str[2] == '\0' || str[2] == '.');
3633}
3634
3635static const char *get_ksymbol(struct module *mod,
3636 unsigned long addr,
3637 unsigned long *size,
3638 unsigned long *offset)
3639{
3640 unsigned int i, best = 0;
3641 unsigned long nextval;
3642
3643 /* At worse, next value is at end of module */
Masami Hiramatsua06f6212009-01-06 14:41:49 -08003644 if (within_module_init(addr, mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003645 nextval = (unsigned long)mod->module_init+mod->init_text_size;
Daniel Walker22a8bde2007-10-18 03:06:07 -07003646 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07003647 nextval = (unsigned long)mod->module_core+mod->core_text_size;
3648
Lucas De Marchi25985ed2011-03-30 22:57:33 -03003649 /* Scan for closest preceding symbol, and next symbol. (ELF
Daniel Walker22a8bde2007-10-18 03:06:07 -07003650 starts real symbols at 1). */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003651 for (i = 1; i < mod->num_symtab; i++) {
3652 if (mod->symtab[i].st_shndx == SHN_UNDEF)
3653 continue;
3654
3655 /* We ignore unnamed symbols: they're uninformative
3656 * and inserted at a whim. */
3657 if (mod->symtab[i].st_value <= addr
3658 && mod->symtab[i].st_value > mod->symtab[best].st_value
3659 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3660 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3661 best = i;
3662 if (mod->symtab[i].st_value > addr
3663 && mod->symtab[i].st_value < nextval
3664 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
3665 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
3666 nextval = mod->symtab[i].st_value;
3667 }
3668
3669 if (!best)
3670 return NULL;
3671
Alexey Dobriyanffb45122007-05-08 00:28:41 -07003672 if (size)
3673 *size = nextval - mod->symtab[best].st_value;
3674 if (offset)
3675 *offset = addr - mod->symtab[best].st_value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003676 return mod->strtab + mod->symtab[best].st_name;
3677}
3678
Rusty Russell6dd06c92008-01-29 17:13:22 -05003679/* For kallsyms to ask for address resolution. NULL means not found. Careful
3680 * not to lock to avoid deadlock on oopses, simply disable preemption. */
Andrew Morton92dfc9d2008-02-08 04:18:43 -08003681const char *module_address_lookup(unsigned long addr,
Rusty Russell6dd06c92008-01-29 17:13:22 -05003682 unsigned long *size,
3683 unsigned long *offset,
3684 char **modname,
3685 char *namebuf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003686{
Rusty Russellcb2a5202008-01-14 00:55:03 -08003687 const char *ret = NULL;
Peter Zijlstrab7df4d12015-05-27 11:09:37 +09303688 struct module *mod;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003689
Rusty Russellcb2a5202008-01-14 00:55:03 -08003690 preempt_disable();
Peter Zijlstrab7df4d12015-05-27 11:09:37 +09303691 mod = __module_address(addr);
3692 if (mod) {
3693 if (modname)
3694 *modname = mod->name;
3695 ret = get_ksymbol(mod, addr, size, offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003696 }
Rusty Russell6dd06c92008-01-29 17:13:22 -05003697 /* Make a copy in here where it's safe */
3698 if (ret) {
3699 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3700 ret = namebuf;
3701 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08003702 preempt_enable();
Peter Zijlstrab7df4d12015-05-27 11:09:37 +09303703
Andrew Morton92dfc9d2008-02-08 04:18:43 -08003704 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003705}
3706
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07003707int lookup_module_symbol_name(unsigned long addr, char *symname)
3708{
3709 struct module *mod;
3710
Rusty Russellcb2a5202008-01-14 00:55:03 -08003711 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02003712 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303713 if (mod->state == MODULE_STATE_UNFORMED)
3714 continue;
Petr Mladek9b20a352014-07-27 07:24:01 +09303715 if (within_module(addr, mod)) {
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07003716 const char *sym;
3717
3718 sym = get_ksymbol(mod, addr, NULL, NULL);
3719 if (!sym)
3720 goto out;
Tejun Heo9281ace2007-07-17 04:03:51 -07003721 strlcpy(symname, sym, KSYM_NAME_LEN);
Rusty Russellcb2a5202008-01-14 00:55:03 -08003722 preempt_enable();
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07003723 return 0;
3724 }
3725 }
3726out:
Rusty Russellcb2a5202008-01-14 00:55:03 -08003727 preempt_enable();
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07003728 return -ERANGE;
3729}
3730
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07003731int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
3732 unsigned long *offset, char *modname, char *name)
3733{
3734 struct module *mod;
3735
Rusty Russellcb2a5202008-01-14 00:55:03 -08003736 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02003737 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303738 if (mod->state == MODULE_STATE_UNFORMED)
3739 continue;
Petr Mladek9b20a352014-07-27 07:24:01 +09303740 if (within_module(addr, mod)) {
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07003741 const char *sym;
3742
3743 sym = get_ksymbol(mod, addr, size, offset);
3744 if (!sym)
3745 goto out;
3746 if (modname)
Tejun Heo9281ace2007-07-17 04:03:51 -07003747 strlcpy(modname, mod->name, MODULE_NAME_LEN);
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07003748 if (name)
Tejun Heo9281ace2007-07-17 04:03:51 -07003749 strlcpy(name, sym, KSYM_NAME_LEN);
Rusty Russellcb2a5202008-01-14 00:55:03 -08003750 preempt_enable();
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07003751 return 0;
3752 }
3753 }
3754out:
Rusty Russellcb2a5202008-01-14 00:55:03 -08003755 preempt_enable();
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07003756 return -ERANGE;
3757}
3758
Alexey Dobriyanea078902007-05-08 00:28:39 -07003759int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
3760 char *name, char *module_name, int *exported)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003761{
3762 struct module *mod;
3763
Rusty Russellcb2a5202008-01-14 00:55:03 -08003764 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02003765 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303766 if (mod->state == MODULE_STATE_UNFORMED)
3767 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003768 if (symnum < mod->num_symtab) {
3769 *value = mod->symtab[symnum].st_value;
3770 *type = mod->symtab[symnum].st_info;
Andreas Gruenbacher098c5ee2006-07-14 00:24:04 -07003771 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
Tejun Heo9281ace2007-07-17 04:03:51 -07003772 KSYM_NAME_LEN);
3773 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
Tim Abbottca4787b2009-01-05 08:40:10 -06003774 *exported = is_exported(name, *value, mod);
Rusty Russellcb2a5202008-01-14 00:55:03 -08003775 preempt_enable();
Alexey Dobriyanea078902007-05-08 00:28:39 -07003776 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003777 }
3778 symnum -= mod->num_symtab;
3779 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08003780 preempt_enable();
Alexey Dobriyanea078902007-05-08 00:28:39 -07003781 return -ERANGE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003782}
3783
3784static unsigned long mod_find_symname(struct module *mod, const char *name)
3785{
3786 unsigned int i;
3787
3788 for (i = 0; i < mod->num_symtab; i++)
Keith Owens54e8ce42006-02-03 03:03:53 -08003789 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
3790 mod->symtab[i].st_info != 'U')
Linus Torvalds1da177e2005-04-16 15:20:36 -07003791 return mod->symtab[i].st_value;
3792 return 0;
3793}
3794
3795/* Look for this name: can be of form module:name. */
3796unsigned long module_kallsyms_lookup_name(const char *name)
3797{
3798 struct module *mod;
3799 char *colon;
3800 unsigned long ret = 0;
3801
3802 /* Don't lock: we're in enough trouble already. */
Rusty Russellcb2a5202008-01-14 00:55:03 -08003803 preempt_disable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07003804 if ((colon = strchr(name, ':')) != NULL) {
Mathias Krause4f6de4d2013-07-02 15:35:11 +09303805 if ((mod = find_module_all(name, colon - name, false)) != NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003806 ret = mod_find_symname(mod, colon+1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003807 } else {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303808 list_for_each_entry_rcu(mod, &modules, list) {
3809 if (mod->state == MODULE_STATE_UNFORMED)
3810 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003811 if ((ret = mod_find_symname(mod, name)) != 0)
3812 break;
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303813 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003814 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08003815 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07003816 return ret;
3817}
Anders Kaseorg75a66612008-12-05 19:03:58 -05003818
3819int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3820 struct module *, unsigned long),
3821 void *data)
3822{
3823 struct module *mod;
3824 unsigned int i;
3825 int ret;
3826
Peter Zijlstra0be964b2015-05-27 11:09:35 +09303827 module_assert_mutex();
3828
Anders Kaseorg75a66612008-12-05 19:03:58 -05003829 list_for_each_entry(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303830 if (mod->state == MODULE_STATE_UNFORMED)
3831 continue;
Anders Kaseorg75a66612008-12-05 19:03:58 -05003832 for (i = 0; i < mod->num_symtab; i++) {
3833 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3834 mod, mod->symtab[i].st_value);
3835 if (ret != 0)
3836 return ret;
3837 }
3838 }
3839 return 0;
3840}
Linus Torvalds1da177e2005-04-16 15:20:36 -07003841#endif /* CONFIG_KALLSYMS */
3842
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003843static char *module_flags(struct module *mod, char *buf)
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003844{
3845 int bx = 0;
3846
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303847 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003848 if (mod->taints ||
3849 mod->state == MODULE_STATE_GOING ||
3850 mod->state == MODULE_STATE_COMING) {
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003851 buf[bx++] = '(';
Kay Sieverscca3e702012-01-13 09:32:15 +10303852 bx += module_flags_taint(mod, buf + bx);
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003853 /* Show a - for module-is-being-unloaded */
3854 if (mod->state == MODULE_STATE_GOING)
3855 buf[bx++] = '-';
3856 /* Show a + for module-is-being-loaded */
3857 if (mod->state == MODULE_STATE_COMING)
3858 buf[bx++] = '+';
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003859 buf[bx++] = ')';
3860 }
3861 buf[bx] = '\0';
3862
3863 return buf;
3864}
3865
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04003866#ifdef CONFIG_PROC_FS
3867/* Called by the /proc file system to return a list of modules. */
3868static void *m_start(struct seq_file *m, loff_t *pos)
3869{
3870 mutex_lock(&module_mutex);
3871 return seq_list_start(&modules, *pos);
3872}
3873
3874static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3875{
3876 return seq_list_next(p, &modules, pos);
3877}
3878
3879static void m_stop(struct seq_file *m, void *p)
3880{
3881 mutex_unlock(&module_mutex);
3882}
3883
Linus Torvalds1da177e2005-04-16 15:20:36 -07003884static int m_show(struct seq_file *m, void *p)
3885{
3886 struct module *mod = list_entry(p, struct module, list);
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003887 char buf[8];
3888
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303889 /* We always ignore unformed modules. */
3890 if (mod->state == MODULE_STATE_UNFORMED)
3891 return 0;
3892
Denys Vlasenko2f0f2a32008-07-22 19:24:27 -05003893 seq_printf(m, "%s %u",
Linus Torvalds1da177e2005-04-16 15:20:36 -07003894 mod->name, mod->init_size + mod->core_size);
3895 print_unload_info(m, mod);
3896
3897 /* Informative for users. */
3898 seq_printf(m, " %s",
Ionut Alexa6da0b562014-11-10 09:31:29 +10303899 mod->state == MODULE_STATE_GOING ? "Unloading" :
3900 mod->state == MODULE_STATE_COMING ? "Loading" :
Linus Torvalds1da177e2005-04-16 15:20:36 -07003901 "Live");
3902 /* Used by oprofile and other similar tools. */
Kees Cook9f36e2c2011-03-22 16:34:22 -07003903 seq_printf(m, " 0x%pK", mod->module_core);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003904
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003905 /* Taints info */
3906 if (mod->taints)
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003907 seq_printf(m, " %s", module_flags(mod, buf));
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003908
Ionut Alexa6da0b562014-11-10 09:31:29 +10303909 seq_puts(m, "\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07003910 return 0;
3911}
3912
3913/* Format: modulename size refcount deps address
3914
3915 Where refcount is a number or -, and deps is a comma-separated list
3916 of depends or -.
3917*/
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04003918static const struct seq_operations modules_op = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003919 .start = m_start,
3920 .next = m_next,
3921 .stop = m_stop,
3922 .show = m_show
3923};
3924
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04003925static int modules_open(struct inode *inode, struct file *file)
3926{
3927 return seq_open(file, &modules_op);
3928}
3929
3930static const struct file_operations proc_modules_operations = {
3931 .open = modules_open,
3932 .read = seq_read,
3933 .llseek = seq_lseek,
3934 .release = seq_release,
3935};
3936
3937static int __init proc_modules_init(void)
3938{
3939 proc_create("modules", 0, NULL, &proc_modules_operations);
3940 return 0;
3941}
3942module_init(proc_modules_init);
3943#endif
3944
Linus Torvalds1da177e2005-04-16 15:20:36 -07003945/* Given an address, look for it in the module exception tables. */
3946const struct exception_table_entry *search_module_extables(unsigned long addr)
3947{
Linus Torvalds1da177e2005-04-16 15:20:36 -07003948 const struct exception_table_entry *e = NULL;
3949 struct module *mod;
3950
Rusty Russell24da1cb2007-07-15 23:41:46 -07003951 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02003952 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303953 if (mod->state == MODULE_STATE_UNFORMED)
3954 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003955 if (mod->num_exentries == 0)
3956 continue;
Daniel Walker22a8bde2007-10-18 03:06:07 -07003957
Linus Torvalds1da177e2005-04-16 15:20:36 -07003958 e = search_extable(mod->extable,
3959 mod->extable + mod->num_exentries - 1,
3960 addr);
3961 if (e)
3962 break;
3963 }
Rusty Russell24da1cb2007-07-15 23:41:46 -07003964 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07003965
3966 /* Now, if we found one, we are running inside it now, hence
Daniel Walker22a8bde2007-10-18 03:06:07 -07003967 we cannot unload the module, hence no refcnt needed. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003968 return e;
3969}
3970
Ingo Molnar4d435f92006-07-03 00:24:24 -07003971/*
Rusty Russelle6104992009-03-31 13:05:31 -06003972 * is_module_address - is this address inside a module?
3973 * @addr: the address to check.
3974 *
3975 * See is_module_text_address() if you simply want to see if the address
3976 * is code (not data).
Ingo Molnar4d435f92006-07-03 00:24:24 -07003977 */
Rusty Russelle6104992009-03-31 13:05:31 -06003978bool is_module_address(unsigned long addr)
Ingo Molnar4d435f92006-07-03 00:24:24 -07003979{
Rusty Russelle6104992009-03-31 13:05:31 -06003980 bool ret;
Ingo Molnar4d435f92006-07-03 00:24:24 -07003981
Rusty Russell24da1cb2007-07-15 23:41:46 -07003982 preempt_disable();
Rusty Russelle6104992009-03-31 13:05:31 -06003983 ret = __module_address(addr) != NULL;
Rusty Russell24da1cb2007-07-15 23:41:46 -07003984 preempt_enable();
Ingo Molnar4d435f92006-07-03 00:24:24 -07003985
Rusty Russelle6104992009-03-31 13:05:31 -06003986 return ret;
Ingo Molnar4d435f92006-07-03 00:24:24 -07003987}
3988
Rusty Russelle6104992009-03-31 13:05:31 -06003989/*
3990 * __module_address - get the module which contains an address.
3991 * @addr: the address.
3992 *
3993 * Must be called with preempt disabled or module mutex held so that
3994 * module doesn't get freed during this.
3995 */
Linus Torvalds714f83d2009-04-05 11:04:19 -07003996struct module *__module_address(unsigned long addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003997{
3998 struct module *mod;
3999
Rusty Russell3a642e92008-07-22 19:24:28 -05004000 if (addr < module_addr_min || addr > module_addr_max)
4001 return NULL;
4002
Peter Zijlstra0be964b2015-05-27 11:09:35 +09304003 module_assert_mutex_or_preempt();
4004
Peter Zijlstra6c9692e2015-05-27 11:09:37 +09304005 mod = mod_find(addr);
Peter Zijlstra93c2e102015-05-27 11:09:37 +09304006 if (mod) {
4007 BUG_ON(!within_module(addr, mod));
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304008 if (mod->state == MODULE_STATE_UNFORMED)
Peter Zijlstra93c2e102015-05-27 11:09:37 +09304009 mod = NULL;
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304010 }
Peter Zijlstra93c2e102015-05-27 11:09:37 +09304011 return mod;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004012}
Tim Abbottc6b37802008-12-05 19:03:59 -05004013EXPORT_SYMBOL_GPL(__module_address);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004014
Rusty Russelle6104992009-03-31 13:05:31 -06004015/*
4016 * is_module_text_address - is this address inside module code?
4017 * @addr: the address to check.
4018 *
4019 * See is_module_address() if you simply want to see if the address is
4020 * anywhere in a module. See kernel_text_address() for testing if an
4021 * address corresponds to kernel or module code.
4022 */
4023bool is_module_text_address(unsigned long addr)
4024{
4025 bool ret;
4026
4027 preempt_disable();
4028 ret = __module_text_address(addr) != NULL;
4029 preempt_enable();
4030
4031 return ret;
4032}
4033
4034/*
4035 * __module_text_address - get the module whose code contains an address.
4036 * @addr: the address.
4037 *
4038 * Must be called with preempt disabled or module mutex held so that
4039 * module doesn't get freed during this.
4040 */
4041struct module *__module_text_address(unsigned long addr)
4042{
4043 struct module *mod = __module_address(addr);
4044 if (mod) {
4045 /* Make sure it's within the text section. */
4046 if (!within(addr, mod->module_init, mod->init_text_size)
4047 && !within(addr, mod->module_core, mod->core_text_size))
4048 mod = NULL;
4049 }
4050 return mod;
4051}
Tim Abbottc6b37802008-12-05 19:03:59 -05004052EXPORT_SYMBOL_GPL(__module_text_address);
Rusty Russelle6104992009-03-31 13:05:31 -06004053
Linus Torvalds1da177e2005-04-16 15:20:36 -07004054/* Don't grab lock, we're oopsing. */
4055void print_modules(void)
4056{
4057 struct module *mod;
Randy Dunlap2bc2d612006-10-02 02:17:02 -07004058 char buf[8];
Linus Torvalds1da177e2005-04-16 15:20:36 -07004059
Linus Torvaldsb2311252009-06-16 11:07:14 -07004060 printk(KERN_DEFAULT "Modules linked in:");
Andi Kleend72b3752008-08-30 10:09:00 +02004061 /* Most callers should already have preempt disabled, but make sure */
4062 preempt_disable();
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304063 list_for_each_entry_rcu(mod, &modules, list) {
4064 if (mod->state == MODULE_STATE_UNFORMED)
4065 continue;
Jiri Slaby27bba4d2014-02-03 11:13:13 +10304066 pr_cont(" %s%s", mod->name, module_flags(mod, buf));
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304067 }
Andi Kleend72b3752008-08-30 10:09:00 +02004068 preempt_enable();
Arjan van de Vene14af7e2008-01-25 21:08:33 +01004069 if (last_unloaded_module[0])
Jiri Slaby27bba4d2014-02-03 11:13:13 +10304070 pr_cont(" [last unloaded: %s]", last_unloaded_module);
4071 pr_cont("\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07004072}
4073
Linus Torvalds1da177e2005-04-16 15:20:36 -07004074#ifdef CONFIG_MODVERSIONS
Rusty Russell8c8ef422009-03-31 13:05:34 -06004075/* Generate the signature for all relevant module structures here.
4076 * If these change, we don't want to try to parse the module. */
4077void module_layout(struct module *mod,
4078 struct modversion_info *ver,
4079 struct kernel_param *kp,
4080 struct kernel_symbol *ks,
Mathieu Desnoyers65498642011-01-26 17:26:22 -05004081 struct tracepoint * const *tp)
Rusty Russell8c8ef422009-03-31 13:05:34 -06004082{
4083}
4084EXPORT_SYMBOL(module_layout);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004085#endif