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Arjan van de Venf71d20e2006-06-28 04:26:45 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
4
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*/
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/module.h>
20#include <linux/moduleloader.h>
Steven Rostedt6d723732009-04-10 14:53:50 -040021#include <linux/ftrace_event.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>
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +040024#include <linux/fs.h>
Roland McGrath6d760132007-10-16 23:26:40 -070025#include <linux/sysfs.h>
Randy Dunlap9f158332005-09-13 01:25:16 -070026#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/slab.h>
28#include <linux/vmalloc.h>
29#include <linux/elf.h>
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +040030#include <linux/proc_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <linux/seq_file.h>
32#include <linux/syscalls.h>
33#include <linux/fcntl.h>
34#include <linux/rcupdate.h>
Randy.Dunlapc59ede72006-01-11 12:17:46 -080035#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#include <linux/cpu.h>
37#include <linux/moduleparam.h>
38#include <linux/errno.h>
39#include <linux/err.h>
40#include <linux/vermagic.h>
41#include <linux/notifier.h>
Al Virof6a57032006-10-18 01:47:25 -040042#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#include <linux/stop_machine.h>
44#include <linux/device.h>
Matt Domschc988d2b2005-06-23 22:05:15 -070045#include <linux/string.h>
Arjan van de Ven97d1f152006-03-23 03:00:24 -080046#include <linux/mutex.h>
Andi Kleend72b3752008-08-30 10:09:00 +020047#include <linux/rculist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070048#include <asm/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070049#include <asm/cacheflush.h>
Bernd Schmidteb8cdec2009-09-21 17:03:57 -070050#include <asm/mmu_context.h>
Sam Ravnborgb817f6f2006-06-09 21:53:55 +020051#include <linux/license.h>
Christoph Lameter6d762392008-02-08 04:18:42 -080052#include <asm/sections.h>
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -040053#include <linux/tracepoint.h>
Steven Rostedt90d595f2008-08-14 15:45:09 -040054#include <linux/ftrace.h>
Arjan van de Ven22a9d642009-01-07 08:45:46 -080055#include <linux/async.h>
Tejun Heofbf59bc2009-02-20 16:29:08 +090056#include <linux/percpu.h>
Catalin Marinas4f2294b2009-06-11 13:23:20 +010057#include <linux/kmemleak.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
Li Zefan7ead8b82009-08-17 16:56:28 +080059#define CREATE_TRACE_POINTS
60#include <trace/events/module.h>
61
Linus Torvalds1da177e2005-04-16 15:20:36 -070062#if 0
63#define DEBUGP printk
64#else
65#define DEBUGP(fmt , a...)
66#endif
67
68#ifndef ARCH_SHF_SMALL
69#define ARCH_SHF_SMALL 0
70#endif
71
72/* If this is set, the section belongs in the init part of the module */
73#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
74
Rusty Russell24da1cb2007-07-15 23:41:46 -070075/* List of modules, protected by module_mutex or preempt_disable
Andi Kleend72b3752008-08-30 10:09:00 +020076 * (delete uses stop_machine/add uses RCU list operations). */
Tim Abbottc6b37802008-12-05 19:03:59 -050077DEFINE_MUTEX(module_mutex);
78EXPORT_SYMBOL_GPL(module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079static LIST_HEAD(modules);
Jason Wessel67fc4e02010-05-20 21:04:21 -050080#ifdef CONFIG_KGDB_KDB
81struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
82#endif /* CONFIG_KGDB_KDB */
83
Linus Torvalds1da177e2005-04-16 15:20:36 -070084
Stephen Rothwell19e45292009-04-14 17:27:18 +100085/* Block module loading/unloading? */
86int modules_disabled = 0;
87
Rusty Russellc9a3ba52008-01-29 17:13:18 -050088/* Waiting for a module to finish initializing? */
89static DECLARE_WAIT_QUEUE_HEAD(module_wq);
90
Alan Sterne041c682006-03-27 01:16:30 -080091static BLOCKING_NOTIFIER_HEAD(module_notify_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -070092
Rusty Russelle6104992009-03-31 13:05:31 -060093/* Bounds of module allocation, for speeding __module_address */
Rusty Russell3a642e92008-07-22 19:24:28 -050094static unsigned long module_addr_min = -1UL, module_addr_max = 0;
95
Linus Torvalds1da177e2005-04-16 15:20:36 -070096int register_module_notifier(struct notifier_block * nb)
97{
Alan Sterne041c682006-03-27 01:16:30 -080098 return blocking_notifier_chain_register(&module_notify_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099}
100EXPORT_SYMBOL(register_module_notifier);
101
102int unregister_module_notifier(struct notifier_block * nb)
103{
Alan Sterne041c682006-03-27 01:16:30 -0800104 return blocking_notifier_chain_unregister(&module_notify_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105}
106EXPORT_SYMBOL(unregister_module_notifier);
107
Matti Linnanvuori9a4b9702007-11-08 08:37:38 -0800108/* We require a truly strong try_module_get(): 0 means failure due to
109 ongoing or failed initialization etc. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110static inline int strong_try_module_get(struct module *mod)
111{
112 if (mod && mod->state == MODULE_STATE_COMING)
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500113 return -EBUSY;
114 if (try_module_get(mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 return 0;
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500116 else
117 return -ENOENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118}
119
Florin Malitafa3ba2e82006-10-11 01:21:48 -0700120static inline void add_taint_module(struct module *mod, unsigned flag)
121{
122 add_taint(flag);
Andi Kleen25ddbb12008-10-15 22:01:41 -0700123 mod->taints |= (1U << flag);
Florin Malitafa3ba2e82006-10-11 01:21:48 -0700124}
125
Robert P. J. Day02a3e592007-05-09 07:26:28 +0200126/*
127 * A thread that wants to hold a reference to a module only while it
128 * is running can call this to safely exit. nfsd and lockd use this.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 */
130void __module_put_and_exit(struct module *mod, long code)
131{
132 module_put(mod);
133 do_exit(code);
134}
135EXPORT_SYMBOL(__module_put_and_exit);
Daniel Walker22a8bde2007-10-18 03:06:07 -0700136
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137/* Find a module section: 0 means not found. */
138static unsigned int find_sec(Elf_Ehdr *hdr,
139 Elf_Shdr *sechdrs,
140 const char *secstrings,
141 const char *name)
142{
143 unsigned int i;
144
145 for (i = 1; i < hdr->e_shnum; i++)
146 /* Alloc bit cleared means "ignore it." */
147 if ((sechdrs[i].sh_flags & SHF_ALLOC)
148 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
149 return i;
150 return 0;
151}
152
Rusty Russell5e458cc2008-10-22 10:00:13 -0500153/* Find a module section, or NULL. */
154static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
155 const char *secstrings, const char *name)
156{
157 /* Section 0 has sh_addr 0. */
158 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
159}
160
161/* Find a module section, or NULL. Fill in number of "objects" in section. */
162static void *section_objs(Elf_Ehdr *hdr,
163 Elf_Shdr *sechdrs,
164 const char *secstrings,
165 const char *name,
166 size_t object_size,
167 unsigned int *num)
168{
169 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
170
171 /* Section 0 has sh_addr 0 and sh_size 0. */
172 *num = sechdrs[sec].sh_size / object_size;
173 return (void *)sechdrs[sec].sh_addr;
174}
175
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176/* Provided by the linker */
177extern const struct kernel_symbol __start___ksymtab[];
178extern const struct kernel_symbol __stop___ksymtab[];
179extern const struct kernel_symbol __start___ksymtab_gpl[];
180extern const struct kernel_symbol __stop___ksymtab_gpl[];
Greg Kroah-Hartman9f28bb72006-03-20 13:17:13 -0800181extern const struct kernel_symbol __start___ksymtab_gpl_future[];
182extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183extern const unsigned long __start___kcrctab[];
184extern const unsigned long __start___kcrctab_gpl[];
Greg Kroah-Hartman9f28bb72006-03-20 13:17:13 -0800185extern const unsigned long __start___kcrctab_gpl_future[];
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500186#ifdef CONFIG_UNUSED_SYMBOLS
187extern const struct kernel_symbol __start___ksymtab_unused[];
188extern const struct kernel_symbol __stop___ksymtab_unused[];
189extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
190extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700191extern const unsigned long __start___kcrctab_unused[];
192extern const unsigned long __start___kcrctab_unused_gpl[];
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500193#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194
195#ifndef CONFIG_MODVERSIONS
196#define symversion(base, idx) NULL
197#else
Andrew Mortonf83ca9f2006-03-28 01:56:20 -0800198#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199#endif
200
Rusty Russelldafd0942008-07-22 19:24:25 -0500201static bool each_symbol_in_section(const struct symsearch *arr,
202 unsigned int arrsize,
203 struct module *owner,
204 bool (*fn)(const struct symsearch *syms,
205 struct module *owner,
206 unsigned int symnum, void *data),
207 void *data)
Sam Ravnborg3fd68052006-02-08 21:16:45 +0100208{
Rusty Russelldafd0942008-07-22 19:24:25 -0500209 unsigned int i, j;
210
211 for (j = 0; j < arrsize; j++) {
212 for (i = 0; i < arr[j].stop - arr[j].start; i++)
213 if (fn(&arr[j], owner, i, data))
214 return true;
215 }
216
217 return false;
Sam Ravnborg3fd68052006-02-08 21:16:45 +0100218}
219
Rusty Russelldafd0942008-07-22 19:24:25 -0500220/* Returns true as soon as fn returns true, otherwise false. */
Tim Abbottc6b37802008-12-05 19:03:59 -0500221bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
222 unsigned int symnum, void *data), void *data)
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700223{
Rusty Russelldafd0942008-07-22 19:24:25 -0500224 struct module *mod;
225 const struct symsearch arr[] = {
226 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
227 NOT_GPL_ONLY, false },
228 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
229 __start___kcrctab_gpl,
230 GPL_ONLY, false },
231 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
232 __start___kcrctab_gpl_future,
233 WILL_BE_GPL_ONLY, false },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500234#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500235 { __start___ksymtab_unused, __stop___ksymtab_unused,
236 __start___kcrctab_unused,
237 NOT_GPL_ONLY, true },
238 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
239 __start___kcrctab_unused_gpl,
240 GPL_ONLY, true },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500241#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500242 };
243
244 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
245 return true;
246
Andi Kleend72b3752008-08-30 10:09:00 +0200247 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russelldafd0942008-07-22 19:24:25 -0500248 struct symsearch arr[] = {
249 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
250 NOT_GPL_ONLY, false },
251 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
252 mod->gpl_crcs,
253 GPL_ONLY, false },
254 { mod->gpl_future_syms,
255 mod->gpl_future_syms + mod->num_gpl_future_syms,
256 mod->gpl_future_crcs,
257 WILL_BE_GPL_ONLY, false },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500258#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500259 { mod->unused_syms,
260 mod->unused_syms + mod->num_unused_syms,
261 mod->unused_crcs,
262 NOT_GPL_ONLY, true },
263 { mod->unused_gpl_syms,
264 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
265 mod->unused_gpl_crcs,
266 GPL_ONLY, true },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500267#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500268 };
269
270 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
271 return true;
272 }
273 return false;
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700274}
Tim Abbottc6b37802008-12-05 19:03:59 -0500275EXPORT_SYMBOL_GPL(each_symbol);
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700276
Rusty Russelldafd0942008-07-22 19:24:25 -0500277struct find_symbol_arg {
278 /* Input */
279 const char *name;
280 bool gplok;
281 bool warn;
282
283 /* Output */
284 struct module *owner;
285 const unsigned long *crc;
Tim Abbott414fd312008-12-05 19:03:56 -0500286 const struct kernel_symbol *sym;
Rusty Russelldafd0942008-07-22 19:24:25 -0500287};
288
289static bool find_symbol_in_section(const struct symsearch *syms,
290 struct module *owner,
291 unsigned int symnum, void *data)
Rusty Russellad9546c2008-05-01 21:14:59 -0500292{
Rusty Russelldafd0942008-07-22 19:24:25 -0500293 struct find_symbol_arg *fsa = data;
294
295 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
296 return false;
297
298 if (!fsa->gplok) {
299 if (syms->licence == GPL_ONLY)
300 return false;
301 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
302 printk(KERN_WARNING "Symbol %s is being used "
303 "by a non-GPL module, which will not "
304 "be allowed in the future\n", fsa->name);
305 printk(KERN_WARNING "Please see the file "
306 "Documentation/feature-removal-schedule.txt "
307 "in the kernel source tree for more details.\n");
308 }
309 }
310
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500311#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500312 if (syms->unused && fsa->warn) {
Rusty Russellad9546c2008-05-01 21:14:59 -0500313 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
Rusty Russelldafd0942008-07-22 19:24:25 -0500314 "however this module is using it.\n", fsa->name);
Rusty Russellad9546c2008-05-01 21:14:59 -0500315 printk(KERN_WARNING
316 "This symbol will go away in the future.\n");
317 printk(KERN_WARNING
318 "Please evalute if this is the right api to use and if "
319 "it really is, submit a report the linux kernel "
320 "mailinglist together with submitting your code for "
321 "inclusion.\n");
322 }
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500323#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500324
325 fsa->owner = owner;
326 fsa->crc = symversion(syms->crcs, symnum);
Tim Abbott414fd312008-12-05 19:03:56 -0500327 fsa->sym = &syms->start[symnum];
Rusty Russellad9546c2008-05-01 21:14:59 -0500328 return true;
329}
330
Tim Abbott414fd312008-12-05 19:03:56 -0500331/* Find a symbol and return it, along with, (optional) crc and
332 * (optional) module which owns it */
Tim Abbottc6b37802008-12-05 19:03:59 -0500333const struct kernel_symbol *find_symbol(const char *name,
334 struct module **owner,
335 const unsigned long **crc,
336 bool gplok,
337 bool warn)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338{
Rusty Russelldafd0942008-07-22 19:24:25 -0500339 struct find_symbol_arg fsa;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340
Rusty Russelldafd0942008-07-22 19:24:25 -0500341 fsa.name = name;
342 fsa.gplok = gplok;
343 fsa.warn = warn;
344
345 if (each_symbol(find_symbol_in_section, &fsa)) {
Rusty Russellad9546c2008-05-01 21:14:59 -0500346 if (owner)
Rusty Russelldafd0942008-07-22 19:24:25 -0500347 *owner = fsa.owner;
348 if (crc)
349 *crc = fsa.crc;
Tim Abbott414fd312008-12-05 19:03:56 -0500350 return fsa.sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 }
Rusty Russellad9546c2008-05-01 21:14:59 -0500352
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353 DEBUGP("Failed to find symbol %s\n", name);
Tim Abbott414fd312008-12-05 19:03:56 -0500354 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355}
Tim Abbottc6b37802008-12-05 19:03:59 -0500356EXPORT_SYMBOL_GPL(find_symbol);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358/* Search for module by name: must hold module_mutex. */
Tim Abbottc6b37802008-12-05 19:03:59 -0500359struct module *find_module(const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360{
361 struct module *mod;
362
363 list_for_each_entry(mod, &modules, list) {
364 if (strcmp(mod->name, name) == 0)
365 return mod;
366 }
367 return NULL;
368}
Tim Abbottc6b37802008-12-05 19:03:59 -0500369EXPORT_SYMBOL_GPL(find_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370
371#ifdef CONFIG_SMP
Tejun Heofbf59bc2009-02-20 16:29:08 +0900372
Tejun Heo259354d2010-03-10 18:56:10 +0900373static inline void __percpu *mod_percpu(struct module *mod)
Tejun Heofbf59bc2009-02-20 16:29:08 +0900374{
Tejun Heo259354d2010-03-10 18:56:10 +0900375 return mod->percpu;
376}
Tejun Heofbf59bc2009-02-20 16:29:08 +0900377
Tejun Heo259354d2010-03-10 18:56:10 +0900378static int percpu_modalloc(struct module *mod,
379 unsigned long size, unsigned long align)
380{
Tejun Heofbf59bc2009-02-20 16:29:08 +0900381 if (align > PAGE_SIZE) {
382 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
Tejun Heo259354d2010-03-10 18:56:10 +0900383 mod->name, align, PAGE_SIZE);
Tejun Heofbf59bc2009-02-20 16:29:08 +0900384 align = PAGE_SIZE;
385 }
386
Tejun Heo259354d2010-03-10 18:56:10 +0900387 mod->percpu = __alloc_reserved_percpu(size, align);
388 if (!mod->percpu) {
Tejun Heofbf59bc2009-02-20 16:29:08 +0900389 printk(KERN_WARNING
390 "Could not allocate %lu bytes percpu data\n", size);
Tejun Heo259354d2010-03-10 18:56:10 +0900391 return -ENOMEM;
392 }
393 mod->percpu_size = size;
394 return 0;
Tejun Heofbf59bc2009-02-20 16:29:08 +0900395}
396
Tejun Heo259354d2010-03-10 18:56:10 +0900397static void percpu_modfree(struct module *mod)
Tejun Heofbf59bc2009-02-20 16:29:08 +0900398{
Tejun Heo259354d2010-03-10 18:56:10 +0900399 free_percpu(mod->percpu);
Tejun Heofbf59bc2009-02-20 16:29:08 +0900400}
401
Tejun Heo6b588c12009-02-20 16:29:07 +0900402static unsigned int find_pcpusec(Elf_Ehdr *hdr,
403 Elf_Shdr *sechdrs,
404 const char *secstrings)
405{
Denys Vlasenko3d9a8542010-02-20 01:03:43 +0100406 return find_sec(hdr, sechdrs, secstrings, ".data..percpu");
Tejun Heo6b588c12009-02-20 16:29:07 +0900407}
408
Tejun Heo259354d2010-03-10 18:56:10 +0900409static void percpu_modcopy(struct module *mod,
410 const void *from, unsigned long size)
Tejun Heo6b588c12009-02-20 16:29:07 +0900411{
412 int cpu;
413
414 for_each_possible_cpu(cpu)
Tejun Heo259354d2010-03-10 18:56:10 +0900415 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
Tejun Heo6b588c12009-02-20 16:29:07 +0900416}
417
Tejun Heo10fad5e2010-03-10 18:57:54 +0900418/**
419 * is_module_percpu_address - test whether address is from module static percpu
420 * @addr: address to test
421 *
422 * Test whether @addr belongs to module static percpu area.
423 *
424 * RETURNS:
425 * %true if @addr is from module static percpu area
426 */
427bool is_module_percpu_address(unsigned long addr)
428{
429 struct module *mod;
430 unsigned int cpu;
431
432 preempt_disable();
433
434 list_for_each_entry_rcu(mod, &modules, list) {
435 if (!mod->percpu_size)
436 continue;
437 for_each_possible_cpu(cpu) {
438 void *start = per_cpu_ptr(mod->percpu, cpu);
439
440 if ((void *)addr >= start &&
441 (void *)addr < start + mod->percpu_size) {
442 preempt_enable();
443 return true;
444 }
445 }
446 }
447
448 preempt_enable();
449 return false;
Daniel Walker22a8bde2007-10-18 03:06:07 -0700450}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451
452#else /* ... !CONFIG_SMP */
Tejun Heo6b588c12009-02-20 16:29:07 +0900453
Tejun Heo259354d2010-03-10 18:56:10 +0900454static inline void __percpu *mod_percpu(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455{
456 return NULL;
457}
Tejun Heo259354d2010-03-10 18:56:10 +0900458static inline int percpu_modalloc(struct module *mod,
459 unsigned long size, unsigned long align)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460{
Tejun Heo259354d2010-03-10 18:56:10 +0900461 return -ENOMEM;
462}
463static inline void percpu_modfree(struct module *mod)
464{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465}
466static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
467 Elf_Shdr *sechdrs,
468 const char *secstrings)
469{
470 return 0;
471}
Tejun Heo259354d2010-03-10 18:56:10 +0900472static inline void percpu_modcopy(struct module *mod,
473 const void *from, unsigned long size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474{
475 /* pcpusec should be 0, and size of that section should be 0. */
476 BUG_ON(size != 0);
477}
Tejun Heo10fad5e2010-03-10 18:57:54 +0900478bool is_module_percpu_address(unsigned long addr)
479{
480 return false;
481}
Tejun Heo6b588c12009-02-20 16:29:07 +0900482
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483#endif /* CONFIG_SMP */
484
Matt Domschc988d2b2005-06-23 22:05:15 -0700485#define MODINFO_ATTR(field) \
486static void setup_modinfo_##field(struct module *mod, const char *s) \
487{ \
488 mod->field = kstrdup(s, GFP_KERNEL); \
489} \
490static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
491 struct module *mod, char *buffer) \
492{ \
493 return sprintf(buffer, "%s\n", mod->field); \
494} \
495static int modinfo_##field##_exists(struct module *mod) \
496{ \
497 return mod->field != NULL; \
498} \
499static void free_modinfo_##field(struct module *mod) \
500{ \
Daniel Walker22a8bde2007-10-18 03:06:07 -0700501 kfree(mod->field); \
502 mod->field = NULL; \
Matt Domschc988d2b2005-06-23 22:05:15 -0700503} \
504static struct module_attribute modinfo_##field = { \
Tejun Heo7b595752007-06-14 03:45:17 +0900505 .attr = { .name = __stringify(field), .mode = 0444 }, \
Matt Domschc988d2b2005-06-23 22:05:15 -0700506 .show = show_modinfo_##field, \
507 .setup = setup_modinfo_##field, \
508 .test = modinfo_##field##_exists, \
509 .free = free_modinfo_##field, \
510};
511
512MODINFO_ATTR(version);
513MODINFO_ATTR(srcversion);
514
Arjan van de Vene14af7e2008-01-25 21:08:33 +0100515static char last_unloaded_module[MODULE_NAME_LEN+1];
516
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -0800517#ifdef CONFIG_MODULE_UNLOAD
Steven Rostedteb0c5372010-03-29 14:25:18 -0400518
519EXPORT_TRACEPOINT_SYMBOL(module_get);
520
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521/* Init the unload section of the module. */
522static void module_unload_init(struct module *mod)
523{
Eric Dumazet720eba32009-02-03 13:31:36 +1030524 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700526 INIT_LIST_HEAD(&mod->source_list);
527 INIT_LIST_HEAD(&mod->target_list);
Nick Piggin5fbfb182010-04-01 19:09:40 +1100528 for_each_possible_cpu(cpu) {
529 per_cpu_ptr(mod->refptr, cpu)->incs = 0;
530 per_cpu_ptr(mod->refptr, cpu)->decs = 0;
531 }
Christoph Lametere1783a22010-01-05 15:34:50 +0900532
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533 /* Hold reference count during initialization. */
Nick Piggin5fbfb182010-04-01 19:09:40 +1100534 __this_cpu_write(mod->refptr->incs, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 /* Backwards compatibility macros put refcount during init. */
536 mod->waiter = current;
537}
538
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539/* Does a already use b? */
540static int already_uses(struct module *a, struct module *b)
541{
542 struct module_use *use;
543
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700544 list_for_each_entry(use, &b->source_list, source_list) {
545 if (use->source == a) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 DEBUGP("%s uses %s!\n", a->name, b->name);
547 return 1;
548 }
549 }
550 DEBUGP("%s does not use %s!\n", a->name, b->name);
551 return 0;
552}
553
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700554/*
555 * Module a uses b
556 * - we add 'a' as a "source", 'b' as a "target" of module use
557 * - the module_use is added to the list of 'b' sources (so
558 * 'b' can walk the list to see who sourced them), and of 'a'
559 * targets (so 'a' can see what modules it targets).
560 */
561static int add_module_usage(struct module *a, struct module *b)
562{
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700563 struct module_use *use;
564
565 DEBUGP("Allocating new usage for %s.\n", a->name);
566 use = kmalloc(sizeof(*use), GFP_ATOMIC);
567 if (!use) {
568 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
569 return -ENOMEM;
570 }
571
572 use->source = a;
573 use->target = b;
574 list_add(&use->source_list, &b->source_list);
575 list_add(&use->target_list, &a->target_list);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700576 return 0;
577}
578
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579/* Module a uses b */
Tim Abbottc6b37802008-12-05 19:03:59 -0500580int use_module(struct module *a, struct module *b)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581{
Rusty Russellc8e21ce2010-06-05 11:17:35 -0600582 int err;
Kay Sievers270a6c42007-01-18 13:26:15 +0100583
Linus Torvalds218ce732010-05-25 16:48:30 -0700584 if (b == NULL || already_uses(a, b)) return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500586 /* If we're interrupted or time out, we fail. */
Linus Torvalds218ce732010-05-25 16:48:30 -0700587 if (wait_event_interruptible_timeout(
588 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
589 30 * HZ) <= 0) {
590 printk("%s: gave up waiting for init of module %s.\n",
591 a->name, b->name);
592 return 0;
593 }
594
595 /* If strong_try_module_get() returned a different error, we fail. */
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500596 if (err)
Linus Torvalds218ce732010-05-25 16:48:30 -0700597 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700599 err = add_module_usage(a, b);
600 if (err) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 module_put(b);
Linus Torvalds218ce732010-05-25 16:48:30 -0700602 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 }
Linus Torvalds218ce732010-05-25 16:48:30 -0700604 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605}
Tim Abbottc6b37802008-12-05 19:03:59 -0500606EXPORT_SYMBOL_GPL(use_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607
608/* Clear the unload stuff of the module. */
609static void module_unload_free(struct module *mod)
610{
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700611 struct module_use *use, *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700613 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
614 struct module *i = use->target;
615 DEBUGP("%s unusing %s\n", mod->name, i->name);
616 module_put(i);
617 list_del(&use->source_list);
618 list_del(&use->target_list);
619 kfree(use);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620 }
621}
622
623#ifdef CONFIG_MODULE_FORCE_UNLOAD
Akinobu Mitafb169792006-01-08 01:04:29 -0800624static inline int try_force_unload(unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625{
626 int ret = (flags & O_TRUNC);
627 if (ret)
Akinobu Mitafb169792006-01-08 01:04:29 -0800628 add_taint(TAINT_FORCED_RMMOD);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 return ret;
630}
631#else
Akinobu Mitafb169792006-01-08 01:04:29 -0800632static inline int try_force_unload(unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633{
634 return 0;
635}
636#endif /* CONFIG_MODULE_FORCE_UNLOAD */
637
638struct stopref
639{
640 struct module *mod;
641 int flags;
642 int *forced;
643};
644
645/* Whole machine is stopped with interrupts off when this runs. */
646static int __try_stop_module(void *_sref)
647{
648 struct stopref *sref = _sref;
649
Rusty Russellda39ba52008-07-22 19:24:25 -0500650 /* If it's not unused, quit unless we're forcing. */
651 if (module_refcount(sref->mod) != 0) {
Akinobu Mitafb169792006-01-08 01:04:29 -0800652 if (!(*sref->forced = try_force_unload(sref->flags)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653 return -EWOULDBLOCK;
654 }
655
656 /* Mark it as dying. */
657 sref->mod->state = MODULE_STATE_GOING;
658 return 0;
659}
660
661static int try_stop_module(struct module *mod, int flags, int *forced)
662{
Rusty Russellda39ba52008-07-22 19:24:25 -0500663 if (flags & O_NONBLOCK) {
664 struct stopref sref = { mod, flags, forced };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665
Rusty Russell9b1a4d32008-07-28 12:16:30 -0500666 return stop_machine(__try_stop_module, &sref, NULL);
Rusty Russellda39ba52008-07-22 19:24:25 -0500667 } else {
668 /* We don't need to stop the machine for this. */
669 mod->state = MODULE_STATE_GOING;
670 synchronize_sched();
671 return 0;
672 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673}
674
675unsigned int module_refcount(struct module *mod)
676{
Nick Piggin5fbfb182010-04-01 19:09:40 +1100677 unsigned int incs = 0, decs = 0;
Eric Dumazet720eba32009-02-03 13:31:36 +1030678 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679
Eric Dumazet720eba32009-02-03 13:31:36 +1030680 for_each_possible_cpu(cpu)
Nick Piggin5fbfb182010-04-01 19:09:40 +1100681 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
682 /*
683 * ensure the incs are added up after the decs.
684 * module_put ensures incs are visible before decs with smp_wmb.
685 *
686 * This 2-count scheme avoids the situation where the refcount
687 * for CPU0 is read, then CPU0 increments the module refcount,
688 * then CPU1 drops that refcount, then the refcount for CPU1 is
689 * read. We would record a decrement but not its corresponding
690 * increment so we would see a low count (disaster).
691 *
692 * Rare situation? But module_refcount can be preempted, and we
693 * might be tallying up 4096+ CPUs. So it is not impossible.
694 */
695 smp_rmb();
696 for_each_possible_cpu(cpu)
697 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
698 return incs - decs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699}
700EXPORT_SYMBOL(module_refcount);
701
702/* This exists whether we can unload or not */
703static void free_module(struct module *mod);
704
705static void wait_for_zero_refcount(struct module *mod)
706{
Matthew Wilcoxa6550202008-02-26 10:47:18 -0500707 /* Since we might sleep for some time, release the mutex first */
Ashutosh Naik6389a382006-03-23 03:00:46 -0800708 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 for (;;) {
710 DEBUGP("Looking at refcount...\n");
711 set_current_state(TASK_UNINTERRUPTIBLE);
712 if (module_refcount(mod) == 0)
713 break;
714 schedule();
715 }
716 current->state = TASK_RUNNING;
Ashutosh Naik6389a382006-03-23 03:00:46 -0800717 mutex_lock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718}
719
Heiko Carstens17da2bd2009-01-14 14:14:10 +0100720SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
721 unsigned int, flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722{
723 struct module *mod;
Greg Kroah-Hartmandfff0a02007-02-23 14:54:57 -0800724 char name[MODULE_NAME_LEN];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 int ret, forced = 0;
726
Kees Cook3d433212009-04-02 15:49:29 -0700727 if (!capable(CAP_SYS_MODULE) || modules_disabled)
Greg Kroah-Hartmandfff0a02007-02-23 14:54:57 -0800728 return -EPERM;
729
730 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
731 return -EFAULT;
732 name[MODULE_NAME_LEN-1] = '\0';
733
Tejun Heo3fc1f1e2010-05-06 18:49:20 +0200734 if (mutex_lock_interruptible(&module_mutex) != 0)
735 return -EINTR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736
737 mod = find_module(name);
738 if (!mod) {
739 ret = -ENOENT;
740 goto out;
741 }
742
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700743 if (!list_empty(&mod->source_list)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744 /* Other modules depend on us: get rid of them first. */
745 ret = -EWOULDBLOCK;
746 goto out;
747 }
748
749 /* Doing init or already dying? */
750 if (mod->state != MODULE_STATE_LIVE) {
751 /* FIXME: if (force), slam module count and wake up
752 waiter --RR */
753 DEBUGP("%s already dying\n", mod->name);
754 ret = -EBUSY;
755 goto out;
756 }
757
758 /* If it has an init func, it must have an exit func to unload */
Rusty Russellaf49d922007-10-16 23:26:27 -0700759 if (mod->init && !mod->exit) {
Akinobu Mitafb169792006-01-08 01:04:29 -0800760 forced = try_force_unload(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 if (!forced) {
762 /* This module can't be removed */
763 ret = -EBUSY;
764 goto out;
765 }
766 }
767
768 /* Set this up before setting mod->state */
769 mod->waiter = current;
770
771 /* Stop the machine so refcounts can't move and disable module. */
772 ret = try_stop_module(mod, flags, &forced);
773 if (ret != 0)
774 goto out;
775
776 /* Never wait if forced. */
777 if (!forced && module_refcount(mod) != 0)
778 wait_for_zero_refcount(mod);
779
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +0200780 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781 /* Final destruction now noone is using it. */
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +0200782 if (mod->exit != NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783 mod->exit();
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +0200784 blocking_notifier_call_chain(&module_notify_list,
785 MODULE_STATE_GOING, mod);
Arjan van de Ven22a9d642009-01-07 08:45:46 -0800786 async_synchronize_full();
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +0200787 mutex_lock(&module_mutex);
Arjan van de Vene14af7e2008-01-25 21:08:33 +0100788 /* Store the name of the last unloaded module for diagnostic purposes */
Rusty Russellefa53452008-01-29 17:13:20 -0500789 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
Jason Barone9d376f2009-02-05 11:51:38 -0500790 ddebug_remove_module(mod->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791 free_module(mod);
792
793 out:
Ashutosh Naik6389a382006-03-23 03:00:46 -0800794 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795 return ret;
796}
797
Jianjun Kongd1e99d72008-12-08 14:26:29 +0800798static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799{
800 struct module_use *use;
801 int printed_something = 0;
802
803 seq_printf(m, " %u ", module_refcount(mod));
804
805 /* Always include a trailing , so userspace can differentiate
806 between this and the old multi-field proc format. */
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700807 list_for_each_entry(use, &mod->source_list, source_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 printed_something = 1;
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700809 seq_printf(m, "%s,", use->source->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 }
811
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 if (mod->init != NULL && mod->exit == NULL) {
813 printed_something = 1;
814 seq_printf(m, "[permanent],");
815 }
816
817 if (!printed_something)
818 seq_printf(m, "-");
819}
820
821void __symbol_put(const char *symbol)
822{
823 struct module *owner;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824
Rusty Russell24da1cb2007-07-15 23:41:46 -0700825 preempt_disable();
Tim Abbott414fd312008-12-05 19:03:56 -0500826 if (!find_symbol(symbol, &owner, NULL, true, false))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827 BUG();
828 module_put(owner);
Rusty Russell24da1cb2007-07-15 23:41:46 -0700829 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830}
831EXPORT_SYMBOL(__symbol_put);
832
Rusty Russell7d1d16e2009-08-26 22:02:54 +0930833/* Note this assumes addr is a function, which it currently always is. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834void symbol_put_addr(void *addr)
835{
Trent Piepho5e376612006-05-15 09:44:06 -0700836 struct module *modaddr;
Rusty Russell7d1d16e2009-08-26 22:02:54 +0930837 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838
Rusty Russell7d1d16e2009-08-26 22:02:54 +0930839 if (core_kernel_text(a))
Trent Piepho5e376612006-05-15 09:44:06 -0700840 return;
841
Rusty Russella6e6abd2009-03-31 13:05:31 -0600842 /* module_text_address is safe here: we're supposed to have reference
843 * to module from symbol_get, so it can't go away. */
Rusty Russell7d1d16e2009-08-26 22:02:54 +0930844 modaddr = __module_text_address(a);
Rusty Russella6e6abd2009-03-31 13:05:31 -0600845 BUG_ON(!modaddr);
Trent Piepho5e376612006-05-15 09:44:06 -0700846 module_put(modaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847}
848EXPORT_SYMBOL_GPL(symbol_put_addr);
849
850static ssize_t show_refcnt(struct module_attribute *mattr,
851 struct module *mod, char *buffer)
852{
Alexey Dobriyan256e2fd2007-08-06 23:47:45 +0400853 return sprintf(buffer, "%u\n", module_refcount(mod));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854}
855
856static struct module_attribute refcnt = {
Tejun Heo7b595752007-06-14 03:45:17 +0900857 .attr = { .name = "refcnt", .mode = 0444 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858 .show = show_refcnt,
859};
860
Al Virof6a57032006-10-18 01:47:25 -0400861void module_put(struct module *module)
862{
863 if (module) {
Christoph Lametere1783a22010-01-05 15:34:50 +0900864 preempt_disable();
Nick Piggin5fbfb182010-04-01 19:09:40 +1100865 smp_wmb(); /* see comment in module_refcount */
866 __this_cpu_inc(module->refptr->decs);
Christoph Lametere1783a22010-01-05 15:34:50 +0900867
Li Zefanae832d12010-03-24 10:57:43 +0800868 trace_module_put(module, _RET_IP_);
Al Virof6a57032006-10-18 01:47:25 -0400869 /* Maybe they're waiting for us to drop reference? */
870 if (unlikely(!module_is_live(module)))
871 wake_up_process(module->waiter);
Christoph Lametere1783a22010-01-05 15:34:50 +0900872 preempt_enable();
Al Virof6a57032006-10-18 01:47:25 -0400873 }
874}
875EXPORT_SYMBOL(module_put);
876
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877#else /* !CONFIG_MODULE_UNLOAD */
Jianjun Kongd1e99d72008-12-08 14:26:29 +0800878static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879{
880 /* We don't know the usage count, or what modules are using. */
881 seq_printf(m, " - -");
882}
883
884static inline void module_unload_free(struct module *mod)
885{
886}
887
Tim Abbottc6b37802008-12-05 19:03:59 -0500888int use_module(struct module *a, struct module *b)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889{
Linus Torvalds218ce732010-05-25 16:48:30 -0700890 return strong_try_module_get(b) == 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700891}
Tim Abbottc6b37802008-12-05 19:03:59 -0500892EXPORT_SYMBOL_GPL(use_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893
894static inline void module_unload_init(struct module *mod)
895{
896}
897#endif /* CONFIG_MODULE_UNLOAD */
898
Kay Sievers1f717402006-11-24 12:15:25 +0100899static ssize_t show_initstate(struct module_attribute *mattr,
900 struct module *mod, char *buffer)
901{
902 const char *state = "unknown";
903
904 switch (mod->state) {
905 case MODULE_STATE_LIVE:
906 state = "live";
907 break;
908 case MODULE_STATE_COMING:
909 state = "coming";
910 break;
911 case MODULE_STATE_GOING:
912 state = "going";
913 break;
914 }
915 return sprintf(buffer, "%s\n", state);
916}
917
918static struct module_attribute initstate = {
Tejun Heo7b595752007-06-14 03:45:17 +0900919 .attr = { .name = "initstate", .mode = 0444 },
Kay Sievers1f717402006-11-24 12:15:25 +0100920 .show = show_initstate,
921};
922
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -0800923static struct module_attribute *modinfo_attrs[] = {
924 &modinfo_version,
925 &modinfo_srcversion,
Kay Sievers1f717402006-11-24 12:15:25 +0100926 &initstate,
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -0800927#ifdef CONFIG_MODULE_UNLOAD
928 &refcnt,
929#endif
930 NULL,
931};
932
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933static const char vermagic[] = VERMAGIC_STRING;
934
Rusty Russellc6e665c2009-03-31 13:05:33 -0600935static int try_to_force_load(struct module *mod, const char *reason)
Linus Torvalds826e4502008-05-04 17:04:16 -0700936{
937#ifdef CONFIG_MODULE_FORCE_LOAD
Andi Kleen25ddbb12008-10-15 22:01:41 -0700938 if (!test_taint(TAINT_FORCED_MODULE))
Rusty Russellc6e665c2009-03-31 13:05:33 -0600939 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
940 mod->name, reason);
Linus Torvalds826e4502008-05-04 17:04:16 -0700941 add_taint_module(mod, TAINT_FORCED_MODULE);
942 return 0;
943#else
944 return -ENOEXEC;
945#endif
946}
947
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948#ifdef CONFIG_MODVERSIONS
Rusty Russelld4703ae2009-12-15 16:28:32 -0600949/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
950static unsigned long maybe_relocated(unsigned long crc,
951 const struct module *crc_owner)
952{
953#ifdef ARCH_RELOCATES_KCRCTAB
954 if (crc_owner == NULL)
955 return crc - (unsigned long)reloc_start;
956#endif
957 return crc;
958}
959
Linus Torvalds1da177e2005-04-16 15:20:36 -0700960static int check_version(Elf_Shdr *sechdrs,
961 unsigned int versindex,
962 const char *symname,
963 struct module *mod,
Rusty Russelld4703ae2009-12-15 16:28:32 -0600964 const unsigned long *crc,
965 const struct module *crc_owner)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700966{
967 unsigned int i, num_versions;
968 struct modversion_info *versions;
969
970 /* Exporting module didn't supply crcs? OK, we're already tainted. */
971 if (!crc)
972 return 1;
973
Rusty Russella5dd6972008-05-09 16:24:21 +1000974 /* No versions at all? modprobe --force does this. */
975 if (versindex == 0)
976 return try_to_force_load(mod, symname) == 0;
977
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978 versions = (void *) sechdrs[versindex].sh_addr;
979 num_versions = sechdrs[versindex].sh_size
980 / sizeof(struct modversion_info);
981
982 for (i = 0; i < num_versions; i++) {
983 if (strcmp(versions[i].name, symname) != 0)
984 continue;
985
Rusty Russelld4703ae2009-12-15 16:28:32 -0600986 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988 DEBUGP("Found checksum %lX vs module %lX\n",
Rusty Russelld4703ae2009-12-15 16:28:32 -0600989 maybe_relocated(*crc, crc_owner), versions[i].crc);
Linus Torvalds826e4502008-05-04 17:04:16 -0700990 goto bad_version;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991 }
Linus Torvalds826e4502008-05-04 17:04:16 -0700992
Rusty Russella5dd6972008-05-09 16:24:21 +1000993 printk(KERN_WARNING "%s: no symbol version for %s\n",
994 mod->name, symname);
995 return 0;
Linus Torvalds826e4502008-05-04 17:04:16 -0700996
997bad_version:
998 printk("%s: disagrees about version of symbol %s\n",
999 mod->name, symname);
1000 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001}
1002
1003static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1004 unsigned int versindex,
1005 struct module *mod)
1006{
1007 const unsigned long *crc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008
Mike Frysinger6560dc12009-07-23 23:42:08 +09301009 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1010 &crc, true, false))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 BUG();
Rusty Russelld4703ae2009-12-15 16:28:32 -06001012 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1013 NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001014}
1015
Rusty Russell91e37a72008-05-09 16:25:28 +10001016/* First part is kernel version, which we ignore if module has crcs. */
1017static inline int same_magic(const char *amagic, const char *bmagic,
1018 bool has_crcs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019{
Rusty Russell91e37a72008-05-09 16:25:28 +10001020 if (has_crcs) {
1021 amagic += strcspn(amagic, " ");
1022 bmagic += strcspn(bmagic, " ");
1023 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001024 return strcmp(amagic, bmagic) == 0;
1025}
1026#else
1027static inline int check_version(Elf_Shdr *sechdrs,
1028 unsigned int versindex,
1029 const char *symname,
1030 struct module *mod,
Rusty Russelld4703ae2009-12-15 16:28:32 -06001031 const unsigned long *crc,
1032 const struct module *crc_owner)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033{
1034 return 1;
1035}
1036
1037static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1038 unsigned int versindex,
1039 struct module *mod)
1040{
1041 return 1;
1042}
1043
Rusty Russell91e37a72008-05-09 16:25:28 +10001044static inline int same_magic(const char *amagic, const char *bmagic,
1045 bool has_crcs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046{
1047 return strcmp(amagic, bmagic) == 0;
1048}
1049#endif /* CONFIG_MODVERSIONS */
1050
1051/* Resolve a symbol for this module. I.e. if we find one, record usage.
1052 Must be holding module_mutex. */
Tim Abbott414fd312008-12-05 19:03:56 -05001053static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
1054 unsigned int versindex,
1055 const char *name,
1056 struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001057{
1058 struct module *owner;
Tim Abbott414fd312008-12-05 19:03:56 -05001059 const struct kernel_symbol *sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060 const unsigned long *crc;
1061
Tim Abbott414fd312008-12-05 19:03:56 -05001062 sym = find_symbol(name, &owner, &crc,
Andi Kleen25ddbb12008-10-15 22:01:41 -07001063 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
Linus Torvalds218ce732010-05-25 16:48:30 -07001064 /* use_module can fail due to OOM,
1065 or module initialization or unloading */
1066 if (sym) {
1067 if (!check_version(sechdrs, versindex, name, mod, crc, owner)
1068 || !use_module(mod, owner))
1069 sym = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001070 }
Linus Torvalds218ce732010-05-25 16:48:30 -07001071 return sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072}
1073
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074/*
1075 * /sys/module/foo/sections stuff
1076 * J. Corbet <corbet@lwn.net>
1077 */
Kay Sievers120fc3d2008-02-21 00:33:20 +01001078#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
Ben Hutchings10b465a2009-12-19 14:43:01 +00001079
1080static inline bool sect_empty(const Elf_Shdr *sect)
1081{
1082 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1083}
1084
Rusty Russella58730c2008-03-13 09:03:44 +00001085struct module_sect_attr
1086{
1087 struct module_attribute mattr;
1088 char *name;
1089 unsigned long address;
1090};
1091
1092struct module_sect_attrs
1093{
1094 struct attribute_group grp;
1095 unsigned int nsections;
1096 struct module_sect_attr attrs[0];
1097};
1098
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099static ssize_t module_sect_show(struct module_attribute *mattr,
1100 struct module *mod, char *buf)
1101{
1102 struct module_sect_attr *sattr =
1103 container_of(mattr, struct module_sect_attr, mattr);
1104 return sprintf(buf, "0x%lx\n", sattr->address);
1105}
1106
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001107static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1108{
Rusty Russella58730c2008-03-13 09:03:44 +00001109 unsigned int section;
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001110
1111 for (section = 0; section < sect_attrs->nsections; section++)
1112 kfree(sect_attrs->attrs[section].name);
1113 kfree(sect_attrs);
1114}
1115
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116static void add_sect_attrs(struct module *mod, unsigned int nsect,
1117 char *secstrings, Elf_Shdr *sechdrs)
1118{
1119 unsigned int nloaded = 0, i, size[2];
1120 struct module_sect_attrs *sect_attrs;
1121 struct module_sect_attr *sattr;
1122 struct attribute **gattr;
Daniel Walker22a8bde2007-10-18 03:06:07 -07001123
Linus Torvalds1da177e2005-04-16 15:20:36 -07001124 /* Count loaded sections and allocate structures */
1125 for (i = 0; i < nsect; i++)
Ben Hutchings10b465a2009-12-19 14:43:01 +00001126 if (!sect_empty(&sechdrs[i]))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001127 nloaded++;
1128 size[0] = ALIGN(sizeof(*sect_attrs)
1129 + nloaded * sizeof(sect_attrs->attrs[0]),
1130 sizeof(sect_attrs->grp.attrs[0]));
1131 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001132 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1133 if (sect_attrs == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001134 return;
1135
1136 /* Setup section attributes. */
1137 sect_attrs->grp.name = "sections";
1138 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1139
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001140 sect_attrs->nsections = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141 sattr = &sect_attrs->attrs[0];
1142 gattr = &sect_attrs->grp.attrs[0];
1143 for (i = 0; i < nsect; i++) {
Ben Hutchings10b465a2009-12-19 14:43:01 +00001144 if (sect_empty(&sechdrs[i]))
Helge Deller35dead42009-12-03 00:29:15 +01001145 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001146 sattr->address = sechdrs[i].sh_addr;
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001147 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1148 GFP_KERNEL);
1149 if (sattr->name == NULL)
1150 goto out;
1151 sect_attrs->nsections++;
Eric W. Biederman361795b2010-02-12 13:41:56 -08001152 sysfs_attr_init(&sattr->mattr.attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001153 sattr->mattr.show = module_sect_show;
1154 sattr->mattr.store = NULL;
1155 sattr->mattr.attr.name = sattr->name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001156 sattr->mattr.attr.mode = S_IRUGO;
1157 *(gattr++) = &(sattr++)->mattr.attr;
1158 }
1159 *gattr = NULL;
1160
1161 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1162 goto out;
1163
1164 mod->sect_attrs = sect_attrs;
1165 return;
1166 out:
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001167 free_sect_attrs(sect_attrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001168}
1169
1170static void remove_sect_attrs(struct module *mod)
1171{
1172 if (mod->sect_attrs) {
1173 sysfs_remove_group(&mod->mkobj.kobj,
1174 &mod->sect_attrs->grp);
1175 /* We are positive that no one is using any sect attrs
1176 * at this point. Deallocate immediately. */
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001177 free_sect_attrs(mod->sect_attrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178 mod->sect_attrs = NULL;
1179 }
1180}
1181
Roland McGrath6d760132007-10-16 23:26:40 -07001182/*
1183 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1184 */
1185
1186struct module_notes_attrs {
1187 struct kobject *dir;
1188 unsigned int notes;
1189 struct bin_attribute attrs[0];
1190};
1191
Chris Wright2c3c8be2010-05-12 18:28:57 -07001192static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
Roland McGrath6d760132007-10-16 23:26:40 -07001193 struct bin_attribute *bin_attr,
1194 char *buf, loff_t pos, size_t count)
1195{
1196 /*
1197 * The caller checked the pos and count against our size.
1198 */
1199 memcpy(buf, bin_attr->private + pos, count);
1200 return count;
1201}
1202
1203static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1204 unsigned int i)
1205{
1206 if (notes_attrs->dir) {
1207 while (i-- > 0)
1208 sysfs_remove_bin_file(notes_attrs->dir,
1209 &notes_attrs->attrs[i]);
Alexey Dobriyane9432092008-09-23 23:51:11 +04001210 kobject_put(notes_attrs->dir);
Roland McGrath6d760132007-10-16 23:26:40 -07001211 }
1212 kfree(notes_attrs);
1213}
1214
1215static void add_notes_attrs(struct module *mod, unsigned int nsect,
1216 char *secstrings, Elf_Shdr *sechdrs)
1217{
1218 unsigned int notes, loaded, i;
1219 struct module_notes_attrs *notes_attrs;
1220 struct bin_attribute *nattr;
1221
Ingo Molnarea6bff32009-08-28 10:44:56 +02001222 /* failed to create section attributes, so can't create notes */
1223 if (!mod->sect_attrs)
1224 return;
1225
Roland McGrath6d760132007-10-16 23:26:40 -07001226 /* Count notes sections and allocate structures. */
1227 notes = 0;
1228 for (i = 0; i < nsect; i++)
Ben Hutchings10b465a2009-12-19 14:43:01 +00001229 if (!sect_empty(&sechdrs[i]) &&
Roland McGrath6d760132007-10-16 23:26:40 -07001230 (sechdrs[i].sh_type == SHT_NOTE))
1231 ++notes;
1232
1233 if (notes == 0)
1234 return;
1235
1236 notes_attrs = kzalloc(sizeof(*notes_attrs)
1237 + notes * sizeof(notes_attrs->attrs[0]),
1238 GFP_KERNEL);
1239 if (notes_attrs == NULL)
1240 return;
1241
1242 notes_attrs->notes = notes;
1243 nattr = &notes_attrs->attrs[0];
1244 for (loaded = i = 0; i < nsect; ++i) {
Ben Hutchings10b465a2009-12-19 14:43:01 +00001245 if (sect_empty(&sechdrs[i]))
Roland McGrath6d760132007-10-16 23:26:40 -07001246 continue;
1247 if (sechdrs[i].sh_type == SHT_NOTE) {
Eric W. Biederman361795b2010-02-12 13:41:56 -08001248 sysfs_bin_attr_init(nattr);
Roland McGrath6d760132007-10-16 23:26:40 -07001249 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1250 nattr->attr.mode = S_IRUGO;
1251 nattr->size = sechdrs[i].sh_size;
1252 nattr->private = (void *) sechdrs[i].sh_addr;
1253 nattr->read = module_notes_read;
1254 ++nattr;
1255 }
1256 ++loaded;
1257 }
1258
Greg Kroah-Hartman4ff6abf2007-11-05 22:24:43 -08001259 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
Roland McGrath6d760132007-10-16 23:26:40 -07001260 if (!notes_attrs->dir)
1261 goto out;
1262
1263 for (i = 0; i < notes; ++i)
1264 if (sysfs_create_bin_file(notes_attrs->dir,
1265 &notes_attrs->attrs[i]))
1266 goto out;
1267
1268 mod->notes_attrs = notes_attrs;
1269 return;
1270
1271 out:
1272 free_notes_attrs(notes_attrs, i);
1273}
1274
1275static void remove_notes_attrs(struct module *mod)
1276{
1277 if (mod->notes_attrs)
1278 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1279}
1280
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281#else
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001282
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1284 char *sectstrings, Elf_Shdr *sechdrs)
1285{
1286}
1287
1288static inline void remove_sect_attrs(struct module *mod)
1289{
1290}
Roland McGrath6d760132007-10-16 23:26:40 -07001291
1292static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1293 char *sectstrings, Elf_Shdr *sechdrs)
1294{
1295}
1296
1297static inline void remove_notes_attrs(struct module *mod)
1298{
1299}
Kay Sievers120fc3d2008-02-21 00:33:20 +01001300#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301
Randy Dunlapef665c12007-02-13 15:19:06 -08001302#ifdef CONFIG_SYSFS
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001303static void add_usage_links(struct module *mod)
1304{
1305#ifdef CONFIG_MODULE_UNLOAD
1306 struct module_use *use;
1307 int nowarn;
1308
1309 list_for_each_entry(use, &mod->target_list, target_list) {
1310 nowarn = sysfs_create_link(use->target->holders_dir,
1311 &mod->mkobj.kobj, mod->name);
1312 }
1313#endif
1314}
1315
1316static void del_usage_links(struct module *mod)
1317{
1318#ifdef CONFIG_MODULE_UNLOAD
1319 struct module_use *use;
1320
1321 list_for_each_entry(use, &mod->target_list, target_list)
1322 sysfs_remove_link(use->target->holders_dir, mod->name);
1323#endif
1324}
1325
Rusty Russell6407ebb22010-06-05 11:17:36 -06001326static int module_add_modinfo_attrs(struct module *mod)
Matt Domschc988d2b2005-06-23 22:05:15 -07001327{
1328 struct module_attribute *attr;
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001329 struct module_attribute *temp_attr;
Matt Domschc988d2b2005-06-23 22:05:15 -07001330 int error = 0;
1331 int i;
1332
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001333 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1334 (ARRAY_SIZE(modinfo_attrs) + 1)),
1335 GFP_KERNEL);
1336 if (!mod->modinfo_attrs)
1337 return -ENOMEM;
1338
1339 temp_attr = mod->modinfo_attrs;
Matt Domschc988d2b2005-06-23 22:05:15 -07001340 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1341 if (!attr->test ||
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001342 (attr->test && attr->test(mod))) {
1343 memcpy(temp_attr, attr, sizeof(*temp_attr));
Eric W. Biederman361795b2010-02-12 13:41:56 -08001344 sysfs_attr_init(&temp_attr->attr);
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001345 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1346 ++temp_attr;
1347 }
Matt Domschc988d2b2005-06-23 22:05:15 -07001348 }
1349 return error;
1350}
1351
Rusty Russell6407ebb22010-06-05 11:17:36 -06001352static void module_remove_modinfo_attrs(struct module *mod)
Matt Domschc988d2b2005-06-23 22:05:15 -07001353{
1354 struct module_attribute *attr;
1355 int i;
1356
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001357 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1358 /* pick a field to test for end of list */
1359 if (!attr->attr.name)
1360 break;
Matt Domschc988d2b2005-06-23 22:05:15 -07001361 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001362 if (attr->free)
1363 attr->free(mod);
Matt Domschc988d2b2005-06-23 22:05:15 -07001364 }
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001365 kfree(mod->modinfo_attrs);
Matt Domschc988d2b2005-06-23 22:05:15 -07001366}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001367
Rusty Russell6407ebb22010-06-05 11:17:36 -06001368static int mod_sysfs_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369{
1370 int err;
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001371 struct kobject *kobj;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -07001373 if (!module_sysfs_initialized) {
1374 printk(KERN_ERR "%s: module sysfs not initialized\n",
Ed Swierk1cc5f712006-09-25 16:25:36 -07001375 mod->name);
1376 err = -EINVAL;
1377 goto out;
1378 }
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001379
1380 kobj = kset_find_obj(module_kset, mod->name);
1381 if (kobj) {
1382 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1383 kobject_put(kobj);
1384 err = -EINVAL;
1385 goto out;
1386 }
1387
Linus Torvalds1da177e2005-04-16 15:20:36 -07001388 mod->mkobj.mod = mod;
Kay Sieverse17e0f52006-11-24 12:15:25 +01001389
Greg Kroah-Hartmanac3c8142007-12-17 23:05:35 -07001390 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1391 mod->mkobj.kobj.kset = module_kset;
1392 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1393 "%s", mod->name);
1394 if (err)
1395 kobject_put(&mod->mkobj.kobj);
Kay Sievers270a6c42007-01-18 13:26:15 +01001396
Kay Sievers97c146e2007-11-29 23:46:11 +01001397 /* delay uevent until full sysfs population */
Kay Sievers270a6c42007-01-18 13:26:15 +01001398out:
1399 return err;
1400}
1401
Rusty Russell6407ebb22010-06-05 11:17:36 -06001402static int mod_sysfs_setup(struct module *mod,
Kay Sievers270a6c42007-01-18 13:26:15 +01001403 struct kernel_param *kparam,
1404 unsigned int num_params)
1405{
1406 int err;
1407
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001408 err = mod_sysfs_init(mod);
1409 if (err)
1410 goto out;
1411
Greg Kroah-Hartman4ff6abf2007-11-05 22:24:43 -08001412 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
Akinobu Mita240936e2007-04-26 00:12:09 -07001413 if (!mod->holders_dir) {
1414 err = -ENOMEM;
Kay Sievers270a6c42007-01-18 13:26:15 +01001415 goto out_unreg;
Akinobu Mita240936e2007-04-26 00:12:09 -07001416 }
Kay Sievers270a6c42007-01-18 13:26:15 +01001417
Linus Torvalds1da177e2005-04-16 15:20:36 -07001418 err = module_param_sysfs_setup(mod, kparam, num_params);
1419 if (err)
Kay Sievers270a6c42007-01-18 13:26:15 +01001420 goto out_unreg_holders;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001421
Matt Domschc988d2b2005-06-23 22:05:15 -07001422 err = module_add_modinfo_attrs(mod);
1423 if (err)
Kay Sieverse17e0f52006-11-24 12:15:25 +01001424 goto out_unreg_param;
Matt Domschc988d2b2005-06-23 22:05:15 -07001425
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001426 add_usage_links(mod);
1427
Kay Sieverse17e0f52006-11-24 12:15:25 +01001428 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001429 return 0;
1430
Kay Sieverse17e0f52006-11-24 12:15:25 +01001431out_unreg_param:
1432 module_param_sysfs_remove(mod);
Kay Sievers270a6c42007-01-18 13:26:15 +01001433out_unreg_holders:
Greg Kroah-Hartman78a2d902007-12-20 08:13:05 -08001434 kobject_put(mod->holders_dir);
Kay Sievers270a6c42007-01-18 13:26:15 +01001435out_unreg:
Kay Sieverse17e0f52006-11-24 12:15:25 +01001436 kobject_put(&mod->mkobj.kobj);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001437out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001438 return err;
1439}
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001440
1441static void mod_sysfs_fini(struct module *mod)
1442{
1443 kobject_put(&mod->mkobj.kobj);
1444}
1445
1446#else /* CONFIG_SYSFS */
1447
Rusty Russell6407ebb22010-06-05 11:17:36 -06001448static inline int mod_sysfs_init(struct module *mod)
1449{
1450 return 0;
1451}
1452
1453static inline int mod_sysfs_setup(struct module *mod,
1454 struct kernel_param *kparam,
1455 unsigned int num_params)
1456{
1457 return 0;
1458}
1459
1460static inline int module_add_modinfo_attrs(struct module *mod)
1461{
1462 return 0;
1463}
1464
1465static inline void module_remove_modinfo_attrs(struct module *mod)
1466{
1467}
1468
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001469static void mod_sysfs_fini(struct module *mod)
1470{
1471}
1472
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001473static void del_usage_links(struct module *mod)
1474{
1475}
1476
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001477#endif /* CONFIG_SYSFS */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001478
1479static void mod_kobject_remove(struct module *mod)
1480{
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001481 del_usage_links(mod);
Matt Domschc988d2b2005-06-23 22:05:15 -07001482 module_remove_modinfo_attrs(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001483 module_param_sysfs_remove(mod);
Greg Kroah-Hartman78a2d902007-12-20 08:13:05 -08001484 kobject_put(mod->mkobj.drivers_dir);
1485 kobject_put(mod->holders_dir);
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001486 mod_sysfs_fini(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487}
1488
1489/*
1490 * unlink the module with the whole machine is stopped with interrupts off
1491 * - this defends against kallsyms not taking locks
1492 */
1493static int __unlink_module(void *_mod)
1494{
1495 struct module *mod = _mod;
1496 list_del(&mod->list);
1497 return 0;
1498}
1499
Robert P. J. Day02a3e592007-05-09 07:26:28 +02001500/* Free a module, remove from lists, etc (must hold module_mutex). */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001501static void free_module(struct module *mod)
1502{
Li Zefan7ead8b82009-08-17 16:56:28 +08001503 trace_module_free(mod);
1504
Linus Torvalds1da177e2005-04-16 15:20:36 -07001505 /* Delete from various lists */
Rusty Russell9b1a4d32008-07-28 12:16:30 -05001506 stop_machine(__unlink_module, mod, NULL);
Roland McGrath6d760132007-10-16 23:26:40 -07001507 remove_notes_attrs(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001508 remove_sect_attrs(mod);
1509 mod_kobject_remove(mod);
1510
1511 /* Arch-specific cleanup. */
1512 module_arch_cleanup(mod);
1513
1514 /* Module unload stuff */
1515 module_unload_free(mod);
1516
Rusty Russelle180a6b2009-03-31 13:05:29 -06001517 /* Free any allocated parameters. */
1518 destroy_params(mod->kp, mod->num_kp);
1519
Linus Torvalds1da177e2005-04-16 15:20:36 -07001520 /* This may be NULL, but that's OK */
1521 module_free(mod, mod->module_init);
1522 kfree(mod->args);
Tejun Heo259354d2010-03-10 18:56:10 +09001523 percpu_modfree(mod);
Christoph Lametere1783a22010-01-05 15:34:50 +09001524#if defined(CONFIG_MODULE_UNLOAD)
Eric Dumazet720eba32009-02-03 13:31:36 +10301525 if (mod->refptr)
Christoph Lametere1783a22010-01-05 15:34:50 +09001526 free_percpu(mod->refptr);
Eric Dumazet720eba32009-02-03 13:31:36 +10301527#endif
Ingo Molnarfbb9ce952006-07-03 00:24:50 -07001528 /* Free lock-classes: */
1529 lockdep_free_key_range(mod->module_core, mod->core_size);
1530
Linus Torvalds1da177e2005-04-16 15:20:36 -07001531 /* Finally, free the core (containing the module structure) */
1532 module_free(mod, mod->module_core);
Bernd Schmidteb8cdec2009-09-21 17:03:57 -07001533
1534#ifdef CONFIG_MPU
1535 update_protections(current->mm);
1536#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001537}
1538
1539void *__symbol_get(const char *symbol)
1540{
1541 struct module *owner;
Tim Abbott414fd312008-12-05 19:03:56 -05001542 const struct kernel_symbol *sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001543
Rusty Russell24da1cb2007-07-15 23:41:46 -07001544 preempt_disable();
Tim Abbott414fd312008-12-05 19:03:56 -05001545 sym = find_symbol(symbol, &owner, NULL, true, true);
1546 if (sym && strong_try_module_get(owner))
1547 sym = NULL;
Rusty Russell24da1cb2007-07-15 23:41:46 -07001548 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001549
Tim Abbott414fd312008-12-05 19:03:56 -05001550 return sym ? (void *)sym->value : NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001551}
1552EXPORT_SYMBOL_GPL(__symbol_get);
1553
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001554/*
1555 * Ensure that an exported symbol [global namespace] does not already exist
Robert P. J. Day02a3e592007-05-09 07:26:28 +02001556 * in the kernel or in some other module's exported symbol table.
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001557 */
1558static int verify_export_symbols(struct module *mod)
1559{
Rusty Russellb2111042008-05-01 21:15:00 -05001560 unsigned int i;
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001561 struct module *owner;
Rusty Russellb2111042008-05-01 21:15:00 -05001562 const struct kernel_symbol *s;
1563 struct {
1564 const struct kernel_symbol *sym;
1565 unsigned int num;
1566 } arr[] = {
1567 { mod->syms, mod->num_syms },
1568 { mod->gpl_syms, mod->num_gpl_syms },
1569 { mod->gpl_future_syms, mod->num_gpl_future_syms },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001570#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russellb2111042008-05-01 21:15:00 -05001571 { mod->unused_syms, mod->num_unused_syms },
1572 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001573#endif
Rusty Russellb2111042008-05-01 21:15:00 -05001574 };
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001575
Rusty Russellb2111042008-05-01 21:15:00 -05001576 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1577 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
Tim Abbott414fd312008-12-05 19:03:56 -05001578 if (find_symbol(s->name, &owner, NULL, true, false)) {
Rusty Russellb2111042008-05-01 21:15:00 -05001579 printk(KERN_ERR
1580 "%s: exports duplicate symbol %s"
1581 " (owned by %s)\n",
1582 mod->name, s->name, module_name(owner));
1583 return -ENOEXEC;
1584 }
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001585 }
Rusty Russellb2111042008-05-01 21:15:00 -05001586 }
1587 return 0;
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001588}
1589
Matti Linnanvuori9a4b9702007-11-08 08:37:38 -08001590/* Change all symbols so that st_value encodes the pointer directly. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001591static int simplify_symbols(Elf_Shdr *sechdrs,
1592 unsigned int symindex,
1593 const char *strtab,
1594 unsigned int versindex,
1595 unsigned int pcpuindex,
1596 struct module *mod)
1597{
1598 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1599 unsigned long secbase;
1600 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1601 int ret = 0;
Tim Abbott414fd312008-12-05 19:03:56 -05001602 const struct kernel_symbol *ksym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001603
1604 for (i = 1; i < n; i++) {
1605 switch (sym[i].st_shndx) {
1606 case SHN_COMMON:
1607 /* We compiled with -fno-common. These are not
1608 supposed to happen. */
1609 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1610 printk("%s: please compile with -fno-common\n",
1611 mod->name);
1612 ret = -ENOEXEC;
1613 break;
1614
1615 case SHN_ABS:
1616 /* Don't need to do anything */
1617 DEBUGP("Absolute symbol: 0x%08lx\n",
1618 (long)sym[i].st_value);
1619 break;
1620
1621 case SHN_UNDEF:
Tim Abbott414fd312008-12-05 19:03:56 -05001622 ksym = resolve_symbol(sechdrs, versindex,
1623 strtab + sym[i].st_name, mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001624 /* Ok if resolved. */
Tim Abbott414fd312008-12-05 19:03:56 -05001625 if (ksym) {
1626 sym[i].st_value = ksym->value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001627 break;
Tim Abbott414fd312008-12-05 19:03:56 -05001628 }
1629
Linus Torvalds1da177e2005-04-16 15:20:36 -07001630 /* Ok if weak. */
1631 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1632 break;
1633
1634 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1635 mod->name, strtab + sym[i].st_name);
1636 ret = -ENOENT;
1637 break;
1638
1639 default:
1640 /* Divert to percpu allocation if a percpu var. */
1641 if (sym[i].st_shndx == pcpuindex)
Tejun Heo259354d2010-03-10 18:56:10 +09001642 secbase = (unsigned long)mod_percpu(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001643 else
1644 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1645 sym[i].st_value += secbase;
1646 break;
1647 }
1648 }
1649
1650 return ret;
1651}
1652
Helge Deller088af9a2008-12-31 12:31:18 +01001653/* Additional bytes needed by arch in front of individual sections */
1654unsigned int __weak arch_mod_section_prepend(struct module *mod,
1655 unsigned int section)
1656{
1657 /* default implementation just returns zero */
1658 return 0;
1659}
1660
Linus Torvalds1da177e2005-04-16 15:20:36 -07001661/* Update size with this section: return offset. */
Helge Deller088af9a2008-12-31 12:31:18 +01001662static long get_offset(struct module *mod, unsigned int *size,
1663 Elf_Shdr *sechdr, unsigned int section)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001664{
1665 long ret;
1666
Helge Deller088af9a2008-12-31 12:31:18 +01001667 *size += arch_mod_section_prepend(mod, section);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001668 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1669 *size = ret + sechdr->sh_size;
1670 return ret;
1671}
1672
1673/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1674 might -- code, read-only data, read-write data, small data. Tally
1675 sizes, and place the offsets into sh_entsize fields: high bit means it
1676 belongs in init. */
1677static void layout_sections(struct module *mod,
1678 const Elf_Ehdr *hdr,
1679 Elf_Shdr *sechdrs,
1680 const char *secstrings)
1681{
1682 static unsigned long const masks[][2] = {
1683 /* NOTE: all executable code must be the first section
1684 * in this array; otherwise modify the text_size
1685 * finder in the two loops below */
1686 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1687 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1688 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1689 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1690 };
1691 unsigned int m, i;
1692
1693 for (i = 0; i < hdr->e_shnum; i++)
1694 sechdrs[i].sh_entsize = ~0UL;
1695
1696 DEBUGP("Core section allocation order:\n");
1697 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1698 for (i = 0; i < hdr->e_shnum; ++i) {
1699 Elf_Shdr *s = &sechdrs[i];
1700
1701 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1702 || (s->sh_flags & masks[m][1])
1703 || s->sh_entsize != ~0UL
Rusty Russell49502672009-03-31 13:05:36 -06001704 || strstarts(secstrings + s->sh_name, ".init"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001705 continue;
Helge Deller088af9a2008-12-31 12:31:18 +01001706 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001707 DEBUGP("\t%s\n", secstrings + s->sh_name);
1708 }
1709 if (m == 0)
1710 mod->core_text_size = mod->core_size;
1711 }
1712
1713 DEBUGP("Init section allocation order:\n");
1714 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1715 for (i = 0; i < hdr->e_shnum; ++i) {
1716 Elf_Shdr *s = &sechdrs[i];
1717
1718 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1719 || (s->sh_flags & masks[m][1])
1720 || s->sh_entsize != ~0UL
Rusty Russell49502672009-03-31 13:05:36 -06001721 || !strstarts(secstrings + s->sh_name, ".init"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001722 continue;
Helge Deller088af9a2008-12-31 12:31:18 +01001723 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001724 | INIT_OFFSET_MASK);
1725 DEBUGP("\t%s\n", secstrings + s->sh_name);
1726 }
1727 if (m == 0)
1728 mod->init_text_size = mod->init_size;
1729 }
1730}
1731
Linus Torvalds1da177e2005-04-16 15:20:36 -07001732static void set_license(struct module *mod, const char *license)
1733{
1734 if (!license)
1735 license = "unspecified";
1736
Florin Malitafa3ba2e82006-10-11 01:21:48 -07001737 if (!license_is_gpl_compatible(license)) {
Andi Kleen25ddbb12008-10-15 22:01:41 -07001738 if (!test_taint(TAINT_PROPRIETARY_MODULE))
Jan Dittmer1d4d2622006-10-28 10:38:38 -07001739 printk(KERN_WARNING "%s: module license '%s' taints "
Florin Malitafa3ba2e82006-10-11 01:21:48 -07001740 "kernel.\n", mod->name, license);
1741 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001742 }
1743}
1744
1745/* Parse tag=value strings from .modinfo section */
1746static char *next_string(char *string, unsigned long *secsize)
1747{
1748 /* Skip non-zero chars */
1749 while (string[0]) {
1750 string++;
1751 if ((*secsize)-- <= 1)
1752 return NULL;
1753 }
1754
1755 /* Skip any zero padding. */
1756 while (!string[0]) {
1757 string++;
1758 if ((*secsize)-- <= 1)
1759 return NULL;
1760 }
1761 return string;
1762}
1763
1764static char *get_modinfo(Elf_Shdr *sechdrs,
1765 unsigned int info,
1766 const char *tag)
1767{
1768 char *p;
1769 unsigned int taglen = strlen(tag);
1770 unsigned long size = sechdrs[info].sh_size;
1771
1772 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1773 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1774 return p + taglen + 1;
1775 }
1776 return NULL;
1777}
1778
Matt Domschc988d2b2005-06-23 22:05:15 -07001779static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1780 unsigned int infoindex)
1781{
1782 struct module_attribute *attr;
1783 int i;
1784
1785 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1786 if (attr->setup)
1787 attr->setup(mod,
1788 get_modinfo(sechdrs,
1789 infoindex,
1790 attr->attr.name));
1791 }
1792}
Matt Domschc988d2b2005-06-23 22:05:15 -07001793
Rusty Russella263f772009-09-25 00:32:58 -06001794static void free_modinfo(struct module *mod)
1795{
1796 struct module_attribute *attr;
1797 int i;
1798
1799 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1800 if (attr->free)
1801 attr->free(mod);
1802 }
1803}
1804
Linus Torvalds1da177e2005-04-16 15:20:36 -07001805#ifdef CONFIG_KALLSYMS
WANG Cong15bba372008-07-24 15:41:48 +01001806
1807/* lookup symbol in given range of kernel_symbols */
1808static const struct kernel_symbol *lookup_symbol(const char *name,
1809 const struct kernel_symbol *start,
1810 const struct kernel_symbol *stop)
1811{
1812 const struct kernel_symbol *ks = start;
1813 for (; ks < stop; ks++)
1814 if (strcmp(ks->name, name) == 0)
1815 return ks;
1816 return NULL;
1817}
1818
Tim Abbottca4787b2009-01-05 08:40:10 -06001819static int is_exported(const char *name, unsigned long value,
1820 const struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001821{
Tim Abbottca4787b2009-01-05 08:40:10 -06001822 const struct kernel_symbol *ks;
1823 if (!mod)
1824 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
Sam Ravnborg3fd68052006-02-08 21:16:45 +01001825 else
Tim Abbottca4787b2009-01-05 08:40:10 -06001826 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1827 return ks != NULL && ks->value == value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001828}
1829
1830/* As per nm */
1831static char elf_type(const Elf_Sym *sym,
1832 Elf_Shdr *sechdrs,
1833 const char *secstrings,
1834 struct module *mod)
1835{
1836 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1837 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1838 return 'v';
1839 else
1840 return 'w';
1841 }
1842 if (sym->st_shndx == SHN_UNDEF)
1843 return 'U';
1844 if (sym->st_shndx == SHN_ABS)
1845 return 'a';
1846 if (sym->st_shndx >= SHN_LORESERVE)
1847 return '?';
1848 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1849 return 't';
1850 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1851 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1852 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1853 return 'r';
1854 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1855 return 'g';
1856 else
1857 return 'd';
1858 }
1859 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1860 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1861 return 's';
1862 else
1863 return 'b';
1864 }
Rusty Russell49502672009-03-31 13:05:36 -06001865 if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001866 return 'n';
1867 return '?';
1868}
1869
Jan Beulich4a496222009-07-06 14:50:42 +01001870static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1871 unsigned int shnum)
1872{
1873 const Elf_Shdr *sec;
1874
1875 if (src->st_shndx == SHN_UNDEF
1876 || src->st_shndx >= shnum
1877 || !src->st_name)
1878 return false;
1879
1880 sec = sechdrs + src->st_shndx;
1881 if (!(sec->sh_flags & SHF_ALLOC)
1882#ifndef CONFIG_KALLSYMS_ALL
1883 || !(sec->sh_flags & SHF_EXECINSTR)
1884#endif
1885 || (sec->sh_entsize & INIT_OFFSET_MASK))
1886 return false;
1887
1888 return true;
1889}
1890
1891static unsigned long layout_symtab(struct module *mod,
1892 Elf_Shdr *sechdrs,
1893 unsigned int symindex,
Jan Beulich554bdfe2009-07-06 14:51:44 +01001894 unsigned int strindex,
Jan Beulich4a496222009-07-06 14:50:42 +01001895 const Elf_Ehdr *hdr,
Jan Beulich554bdfe2009-07-06 14:51:44 +01001896 const char *secstrings,
1897 unsigned long *pstroffs,
1898 unsigned long *strmap)
Jan Beulich4a496222009-07-06 14:50:42 +01001899{
1900 unsigned long symoffs;
1901 Elf_Shdr *symsect = sechdrs + symindex;
Jan Beulich554bdfe2009-07-06 14:51:44 +01001902 Elf_Shdr *strsect = sechdrs + strindex;
Jan Beulich4a496222009-07-06 14:50:42 +01001903 const Elf_Sym *src;
Jan Beulich554bdfe2009-07-06 14:51:44 +01001904 const char *strtab;
Jan Beulich4a496222009-07-06 14:50:42 +01001905 unsigned int i, nsrc, ndst;
1906
1907 /* Put symbol section at end of init part of module. */
1908 symsect->sh_flags |= SHF_ALLOC;
1909 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1910 symindex) | INIT_OFFSET_MASK;
1911 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
1912
1913 src = (void *)hdr + symsect->sh_offset;
1914 nsrc = symsect->sh_size / sizeof(*src);
Jan Beulich554bdfe2009-07-06 14:51:44 +01001915 strtab = (void *)hdr + strsect->sh_offset;
Jan Beulich4a496222009-07-06 14:50:42 +01001916 for (ndst = i = 1; i < nsrc; ++i, ++src)
Jan Beulich554bdfe2009-07-06 14:51:44 +01001917 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
1918 unsigned int j = src->st_name;
1919
1920 while(!__test_and_set_bit(j, strmap) && strtab[j])
1921 ++j;
Jan Beulich4a496222009-07-06 14:50:42 +01001922 ++ndst;
Jan Beulich554bdfe2009-07-06 14:51:44 +01001923 }
Jan Beulich4a496222009-07-06 14:50:42 +01001924
1925 /* Append room for core symbols at end of core part. */
1926 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
1927 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
1928
Jan Beulich554bdfe2009-07-06 14:51:44 +01001929 /* Put string table section at end of init part of module. */
1930 strsect->sh_flags |= SHF_ALLOC;
1931 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
1932 strindex) | INIT_OFFSET_MASK;
1933 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
1934
1935 /* Append room for core symbols' strings at end of core part. */
1936 *pstroffs = mod->core_size;
1937 __set_bit(0, strmap);
1938 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
1939
Jan Beulich4a496222009-07-06 14:50:42 +01001940 return symoffs;
1941}
1942
Linus Torvalds1da177e2005-04-16 15:20:36 -07001943static void add_kallsyms(struct module *mod,
1944 Elf_Shdr *sechdrs,
Jan Beulich4a496222009-07-06 14:50:42 +01001945 unsigned int shnum,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001946 unsigned int symindex,
1947 unsigned int strindex,
Jan Beulich4a496222009-07-06 14:50:42 +01001948 unsigned long symoffs,
Jan Beulich554bdfe2009-07-06 14:51:44 +01001949 unsigned long stroffs,
1950 const char *secstrings,
1951 unsigned long *strmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001952{
Jan Beulich4a496222009-07-06 14:50:42 +01001953 unsigned int i, ndst;
1954 const Elf_Sym *src;
1955 Elf_Sym *dst;
Jan Beulich554bdfe2009-07-06 14:51:44 +01001956 char *s;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001957
1958 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1959 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1960 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1961
1962 /* Set types up while we still have access to sections. */
1963 for (i = 0; i < mod->num_symtab; i++)
1964 mod->symtab[i].st_info
1965 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
Jan Beulich4a496222009-07-06 14:50:42 +01001966
1967 mod->core_symtab = dst = mod->module_core + symoffs;
1968 src = mod->symtab;
1969 *dst = *src;
1970 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
1971 if (!is_core_symbol(src, sechdrs, shnum))
1972 continue;
1973 dst[ndst] = *src;
Jan Beulich554bdfe2009-07-06 14:51:44 +01001974 dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
Jan Beulich4a496222009-07-06 14:50:42 +01001975 ++ndst;
1976 }
1977 mod->core_num_syms = ndst;
Jan Beulich554bdfe2009-07-06 14:51:44 +01001978
1979 mod->core_strtab = s = mod->module_core + stroffs;
1980 for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
1981 if (test_bit(i, strmap))
1982 *++s = mod->strtab[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001983}
1984#else
Jan Beulich4a496222009-07-06 14:50:42 +01001985static inline unsigned long layout_symtab(struct module *mod,
1986 Elf_Shdr *sechdrs,
1987 unsigned int symindex,
Jan Beulich554bdfe2009-07-06 14:51:44 +01001988 unsigned int strindex,
Paul Mundt3ae91c22009-10-01 15:43:54 -07001989 const Elf_Ehdr *hdr,
Jan Beulich554bdfe2009-07-06 14:51:44 +01001990 const char *secstrings,
1991 unsigned long *pstroffs,
1992 unsigned long *strmap)
Jan Beulich4a496222009-07-06 14:50:42 +01001993{
Paul Mundt3ae91c22009-10-01 15:43:54 -07001994 return 0;
Jan Beulich4a496222009-07-06 14:50:42 +01001995}
Paul Mundt3ae91c22009-10-01 15:43:54 -07001996
Linus Torvalds1da177e2005-04-16 15:20:36 -07001997static inline void add_kallsyms(struct module *mod,
1998 Elf_Shdr *sechdrs,
Jan Beulich4a496222009-07-06 14:50:42 +01001999 unsigned int shnum,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002000 unsigned int symindex,
2001 unsigned int strindex,
Jan Beulich4a496222009-07-06 14:50:42 +01002002 unsigned long symoffs,
Jan Beulich554bdfe2009-07-06 14:51:44 +01002003 unsigned long stroffs,
2004 const char *secstrings,
2005 const unsigned long *strmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002006{
2007}
2008#endif /* CONFIG_KALLSYMS */
2009
Jason Barone9d376f2009-02-05 11:51:38 -05002010static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
Rusty Russell5e458cc2008-10-22 10:00:13 -05002011{
Jason Barone9d376f2009-02-05 11:51:38 -05002012#ifdef CONFIG_DYNAMIC_DEBUG
2013 if (ddebug_add_module(debug, num, debug->modname))
2014 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2015 debug->modname);
2016#endif
Rusty Russell5e458cc2008-10-22 10:00:13 -05002017}
Jason Baron346e15b2008-08-12 16:46:19 -04002018
Rusty Russell3a642e92008-07-22 19:24:28 -05002019static void *module_alloc_update_bounds(unsigned long size)
2020{
2021 void *ret = module_alloc(size);
2022
2023 if (ret) {
2024 /* Update module bounds. */
2025 if ((unsigned long)ret < module_addr_min)
2026 module_addr_min = (unsigned long)ret;
2027 if ((unsigned long)ret + size > module_addr_max)
2028 module_addr_max = (unsigned long)ret + size;
2029 }
2030 return ret;
2031}
2032
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002033#ifdef CONFIG_DEBUG_KMEMLEAK
2034static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2035 Elf_Shdr *sechdrs, char *secstrings)
2036{
2037 unsigned int i;
2038
2039 /* only scan the sections containing data */
Catalin Marinasc017b4b2009-10-28 13:33:09 +00002040 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002041
2042 for (i = 1; i < hdr->e_shnum; i++) {
2043 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2044 continue;
2045 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
2046 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
2047 continue;
2048
Catalin Marinasc017b4b2009-10-28 13:33:09 +00002049 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002050 sechdrs[i].sh_size, GFP_KERNEL);
2051 }
2052}
2053#else
2054static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2055 Elf_Shdr *sechdrs, char *secstrings)
2056{
2057}
2058#endif
2059
Linus Torvalds1da177e2005-04-16 15:20:36 -07002060/* Allocate and load the module: note that size of section 0 is always
2061 zero, and we rely on this for optional sections. */
Linus Torvaldsffb4ba72008-08-25 11:10:26 -07002062static noinline struct module *load_module(void __user *umod,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002063 unsigned long len,
2064 const char __user *uargs)
2065{
2066 Elf_Ehdr *hdr;
2067 Elf_Shdr *sechdrs;
2068 char *secstrings, *args, *modmagic, *strtab = NULL;
Greg Kroah-Hartman061b1bd2008-09-24 14:46:44 -07002069 char *staging;
Andrew Morton84860f92006-06-28 04:26:46 -07002070 unsigned int i;
2071 unsigned int symindex = 0;
2072 unsigned int strindex = 0;
Rusty Russell5e458cc2008-10-22 10:00:13 -05002073 unsigned int modindex, versindex, infoindex, pcpuindex;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002074 struct module *mod;
2075 long err = 0;
Tejun Heo259354d2010-03-10 18:56:10 +09002076 void *ptr = NULL; /* Stops spurious gcc warning */
Jan Beulich554bdfe2009-07-06 14:51:44 +01002077 unsigned long symoffs, stroffs, *strmap;
Rusty Russell293a7cf2010-05-31 19:53:50 +09302078 void __percpu *percpu;
Paul Mundt3ae91c22009-10-01 15:43:54 -07002079
Thomas Koeller378bac82005-09-06 15:17:11 -07002080 mm_segment_t old_fs;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002081
2082 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2083 umod, len, uargs);
2084 if (len < sizeof(*hdr))
2085 return ERR_PTR(-ENOEXEC);
2086
2087 /* Suck in entire file: we'll want most of it. */
2088 /* vmalloc barfs on "unusual" numbers. Check here */
2089 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
2090 return ERR_PTR(-ENOMEM);
Heiko Carstens9e018922008-12-22 12:36:31 +01002091
Linus Torvalds1da177e2005-04-16 15:20:36 -07002092 if (copy_from_user(hdr, umod, len) != 0) {
2093 err = -EFAULT;
2094 goto free_hdr;
2095 }
2096
2097 /* Sanity checks against insmoding binaries or wrong arch,
2098 weird elf version */
Cyrill Gorcunovc4ea6fc2008-05-14 16:27:29 -07002099 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
Linus Torvalds1da177e2005-04-16 15:20:36 -07002100 || hdr->e_type != ET_REL
2101 || !elf_check_arch(hdr)
2102 || hdr->e_shentsize != sizeof(*sechdrs)) {
2103 err = -ENOEXEC;
2104 goto free_hdr;
2105 }
2106
2107 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
2108 goto truncated;
2109
2110 /* Convenience variables */
2111 sechdrs = (void *)hdr + hdr->e_shoff;
2112 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
2113 sechdrs[0].sh_addr = 0;
2114
2115 for (i = 1; i < hdr->e_shnum; i++) {
2116 if (sechdrs[i].sh_type != SHT_NOBITS
2117 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
2118 goto truncated;
2119
2120 /* Mark all sections sh_addr with their address in the
2121 temporary image. */
2122 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
2123
2124 /* Internal symbols and strings. */
2125 if (sechdrs[i].sh_type == SHT_SYMTAB) {
2126 symindex = i;
2127 strindex = sechdrs[i].sh_link;
2128 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
2129 }
2130#ifndef CONFIG_MODULE_UNLOAD
2131 /* Don't load .exit sections */
Rusty Russell49502672009-03-31 13:05:36 -06002132 if (strstarts(secstrings+sechdrs[i].sh_name, ".exit"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002133 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
2134#endif
2135 }
2136
2137 modindex = find_sec(hdr, sechdrs, secstrings,
2138 ".gnu.linkonce.this_module");
2139 if (!modindex) {
2140 printk(KERN_WARNING "No module found in object\n");
2141 err = -ENOEXEC;
2142 goto free_hdr;
2143 }
Rusty Russell5e458cc2008-10-22 10:00:13 -05002144 /* This is temporary: point mod into copy of data. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002145 mod = (void *)sechdrs[modindex].sh_addr;
2146
2147 if (symindex == 0) {
2148 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2149 mod->name);
2150 err = -ENOEXEC;
2151 goto free_hdr;
2152 }
2153
Linus Torvalds1da177e2005-04-16 15:20:36 -07002154 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
2155 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
2156 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
2157
Rusty Russellea01e792008-03-13 09:02:17 +00002158 /* Don't keep modinfo and version sections. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002159 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
Rusty Russellea01e792008-03-13 09:02:17 +00002160 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002161
2162 /* Check module struct version now, before we try to use module. */
2163 if (!check_modstruct_version(sechdrs, versindex, mod)) {
2164 err = -ENOEXEC;
2165 goto free_hdr;
2166 }
2167
2168 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2169 /* This is allowed: modprobe --force will invalidate it. */
2170 if (!modmagic) {
Rusty Russellc6e665c2009-03-31 13:05:33 -06002171 err = try_to_force_load(mod, "bad vermagic");
Linus Torvalds826e4502008-05-04 17:04:16 -07002172 if (err)
2173 goto free_hdr;
Rusty Russell91e37a72008-05-09 16:25:28 +10002174 } else if (!same_magic(modmagic, vermagic, versindex)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002175 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2176 mod->name, modmagic, vermagic);
2177 err = -ENOEXEC;
2178 goto free_hdr;
2179 }
2180
Greg Kroah-Hartman061b1bd2008-09-24 14:46:44 -07002181 staging = get_modinfo(sechdrs, infoindex, "staging");
2182 if (staging) {
2183 add_taint_module(mod, TAINT_CRAP);
2184 printk(KERN_WARNING "%s: module is from the staging directory,"
2185 " the quality is unknown, you have been warned.\n",
2186 mod->name);
2187 }
2188
Linus Torvalds1da177e2005-04-16 15:20:36 -07002189 /* Now copy in args */
Davi Arnaut24277dd2006-03-24 03:18:43 -08002190 args = strndup_user(uargs, ~0UL >> 1);
2191 if (IS_ERR(args)) {
2192 err = PTR_ERR(args);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002193 goto free_hdr;
2194 }
Andrew Morton8e08b752006-02-07 12:58:45 -08002195
Jan Beulich554bdfe2009-07-06 14:51:44 +01002196 strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size)
2197 * sizeof(long), GFP_KERNEL);
2198 if (!strmap) {
2199 err = -ENOMEM;
2200 goto free_mod;
2201 }
2202
Linus Torvalds1da177e2005-04-16 15:20:36 -07002203 if (find_module(mod->name)) {
2204 err = -EEXIST;
2205 goto free_mod;
2206 }
2207
2208 mod->state = MODULE_STATE_COMING;
2209
2210 /* Allow arches to frob section contents and sizes. */
2211 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
2212 if (err < 0)
2213 goto free_mod;
2214
2215 if (pcpuindex) {
2216 /* We have a special allocation for this section. */
Tejun Heo259354d2010-03-10 18:56:10 +09002217 err = percpu_modalloc(mod, sechdrs[pcpuindex].sh_size,
2218 sechdrs[pcpuindex].sh_addralign);
2219 if (err)
Masami Hiramatsu6e2b7572009-03-16 18:13:36 -04002220 goto free_mod;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002221 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002222 }
Rusty Russell293a7cf2010-05-31 19:53:50 +09302223 /* Keep this around for failure path. */
2224 percpu = mod_percpu(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002225
2226 /* Determine total sizes, and put offsets in sh_entsize. For now
2227 this is done generically; there doesn't appear to be any
2228 special cases for the architectures. */
2229 layout_sections(mod, hdr, sechdrs, secstrings);
Jan Beulich554bdfe2009-07-06 14:51:44 +01002230 symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr,
2231 secstrings, &stroffs, strmap);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002232
2233 /* Do the allocs. */
Rusty Russell3a642e92008-07-22 19:24:28 -05002234 ptr = module_alloc_update_bounds(mod->core_size);
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002235 /*
2236 * The pointer to this block is stored in the module structure
2237 * which is inside the block. Just mark it as not being a
2238 * leak.
2239 */
2240 kmemleak_not_leak(ptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002241 if (!ptr) {
2242 err = -ENOMEM;
2243 goto free_percpu;
2244 }
2245 memset(ptr, 0, mod->core_size);
2246 mod->module_core = ptr;
2247
Rusty Russell3a642e92008-07-22 19:24:28 -05002248 ptr = module_alloc_update_bounds(mod->init_size);
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002249 /*
2250 * The pointer to this block is stored in the module structure
2251 * which is inside the block. This block doesn't need to be
2252 * scanned as it contains data and code that will be freed
2253 * after the module is initialized.
2254 */
2255 kmemleak_ignore(ptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002256 if (!ptr && mod->init_size) {
2257 err = -ENOMEM;
2258 goto free_core;
2259 }
2260 memset(ptr, 0, mod->init_size);
2261 mod->module_init = ptr;
2262
2263 /* Transfer each section which specifies SHF_ALLOC */
2264 DEBUGP("final section addresses:\n");
2265 for (i = 0; i < hdr->e_shnum; i++) {
2266 void *dest;
2267
2268 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2269 continue;
2270
2271 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2272 dest = mod->module_init
2273 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2274 else
2275 dest = mod->module_core + sechdrs[i].sh_entsize;
2276
2277 if (sechdrs[i].sh_type != SHT_NOBITS)
2278 memcpy(dest, (void *)sechdrs[i].sh_addr,
2279 sechdrs[i].sh_size);
2280 /* Update sh_addr to point to copy in image. */
2281 sechdrs[i].sh_addr = (unsigned long)dest;
2282 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2283 }
2284 /* Module has been moved. */
2285 mod = (void *)sechdrs[modindex].sh_addr;
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002286 kmemleak_load_module(mod, hdr, sechdrs, secstrings);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002287
Christoph Lametere1783a22010-01-05 15:34:50 +09002288#if defined(CONFIG_MODULE_UNLOAD)
2289 mod->refptr = alloc_percpu(struct module_ref);
Masami Hiramatsu6e2b7572009-03-16 18:13:36 -04002290 if (!mod->refptr) {
2291 err = -ENOMEM;
2292 goto free_init;
2293 }
2294#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002295 /* Now we've moved module, initialize linked lists, etc. */
2296 module_unload_init(mod);
2297
2298 /* Set up license info based on the info section */
2299 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2300
Pavel Roskin9b37ccf2008-02-28 17:11:02 -05002301 /*
2302 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2303 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2304 * using GPL-only symbols it needs.
2305 */
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002306 if (strcmp(mod->name, "ndiswrapper") == 0)
Pavel Roskin9b37ccf2008-02-28 17:11:02 -05002307 add_taint(TAINT_PROPRIETARY_MODULE);
2308
2309 /* driverloader was caught wrongly pretending to be under GPL */
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002310 if (strcmp(mod->name, "driverloader") == 0)
2311 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
Dave Jones9841d61d2006-01-08 01:03:41 -08002312
Matt Domschc988d2b2005-06-23 22:05:15 -07002313 /* Set up MODINFO_ATTR fields */
2314 setup_modinfo(mod, sechdrs, infoindex);
Matt Domschc988d2b2005-06-23 22:05:15 -07002315
Linus Torvalds1da177e2005-04-16 15:20:36 -07002316 /* Fix up syms, so that st_value is a pointer to location. */
2317 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2318 mod);
2319 if (err < 0)
2320 goto cleanup;
2321
Rusty Russell5e458cc2008-10-22 10:00:13 -05002322 /* Now we've got everything in the final locations, we can
2323 * find optional sections. */
Rusty Russelle180a6b2009-03-31 13:05:29 -06002324 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2325 sizeof(*mod->kp), &mod->num_kp);
Rusty Russell5e458cc2008-10-22 10:00:13 -05002326 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2327 sizeof(*mod->syms), &mod->num_syms);
2328 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2329 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2330 sizeof(*mod->gpl_syms),
2331 &mod->num_gpl_syms);
2332 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2333 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2334 "__ksymtab_gpl_future",
2335 sizeof(*mod->gpl_future_syms),
2336 &mod->num_gpl_future_syms);
2337 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2338 "__kcrctab_gpl_future");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002339
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05002340#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russell5e458cc2008-10-22 10:00:13 -05002341 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2342 "__ksymtab_unused",
2343 sizeof(*mod->unused_syms),
2344 &mod->num_unused_syms);
2345 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2346 "__kcrctab_unused");
2347 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2348 "__ksymtab_unused_gpl",
2349 sizeof(*mod->unused_gpl_syms),
2350 &mod->num_unused_gpl_syms);
2351 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2352 "__kcrctab_unused_gpl");
2353#endif
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -07002354#ifdef CONFIG_CONSTRUCTORS
2355 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2356 sizeof(*mod->ctors), &mod->num_ctors);
2357#endif
Rusty Russell5e458cc2008-10-22 10:00:13 -05002358
Rusty Russell5e458cc2008-10-22 10:00:13 -05002359#ifdef CONFIG_TRACEPOINTS
2360 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2361 "__tracepoints",
2362 sizeof(*mod->tracepoints),
2363 &mod->num_tracepoints);
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05002364#endif
Steven Rostedt6d723732009-04-10 14:53:50 -04002365#ifdef CONFIG_EVENT_TRACING
2366 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2367 "_ftrace_events",
2368 sizeof(*mod->trace_events),
2369 &mod->num_trace_events);
Catalin Marinasa6f5aa12009-10-28 13:33:10 +00002370 /*
2371 * This section contains pointers to allocated objects in the trace
2372 * code and not scanning it leads to false positives.
2373 */
2374 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2375 mod->num_trace_events, GFP_KERNEL);
Steven Rostedt6d723732009-04-10 14:53:50 -04002376#endif
Steven Rostedt93eb6772009-04-15 13:24:06 -04002377#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2378 /* sechdrs[0].sh_size is always zero */
2379 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2380 "__mcount_loc",
2381 sizeof(*mod->ftrace_callsites),
2382 &mod->num_ftrace_callsites);
2383#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002384#ifdef CONFIG_MODVERSIONS
Rusty Russell5e458cc2008-10-22 10:00:13 -05002385 if ((mod->num_syms && !mod->crcs)
2386 || (mod->num_gpl_syms && !mod->gpl_crcs)
2387 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05002388#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russell5e458cc2008-10-22 10:00:13 -05002389 || (mod->num_unused_syms && !mod->unused_crcs)
2390 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05002391#endif
2392 ) {
Rusty Russellc6e665c2009-03-31 13:05:33 -06002393 err = try_to_force_load(mod,
2394 "no versions for exported symbols");
Linus Torvalds826e4502008-05-04 17:04:16 -07002395 if (err)
2396 goto cleanup;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002397 }
2398#endif
2399
2400 /* Now do relocations. */
2401 for (i = 1; i < hdr->e_shnum; i++) {
2402 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2403 unsigned int info = sechdrs[i].sh_info;
2404
2405 /* Not a valid relocation section? */
2406 if (info >= hdr->e_shnum)
2407 continue;
2408
2409 /* Don't bother with non-allocated sections */
2410 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2411 continue;
2412
2413 if (sechdrs[i].sh_type == SHT_REL)
2414 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2415 else if (sechdrs[i].sh_type == SHT_RELA)
2416 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2417 mod);
2418 if (err < 0)
2419 goto cleanup;
2420 }
2421
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002422 /* Find duplicate symbols */
2423 err = verify_export_symbols(mod);
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002424 if (err < 0)
2425 goto cleanup;
2426
Linus Torvalds1da177e2005-04-16 15:20:36 -07002427 /* Set up and sort exception table */
Rusty Russell5e458cc2008-10-22 10:00:13 -05002428 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2429 sizeof(*mod->extable), &mod->num_exentries);
2430 sort_extable(mod->extable, mod->extable + mod->num_exentries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002431
2432 /* Finally, copy percpu area over. */
Tejun Heo259354d2010-03-10 18:56:10 +09002433 percpu_modcopy(mod, (void *)sechdrs[pcpuindex].sh_addr,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002434 sechdrs[pcpuindex].sh_size);
2435
Jan Beulich4a496222009-07-06 14:50:42 +01002436 add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex,
Jan Beulich554bdfe2009-07-06 14:51:44 +01002437 symoffs, stroffs, secstrings, strmap);
2438 kfree(strmap);
2439 strmap = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002440
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04002441 if (!mod->taints) {
Jason Barone9d376f2009-02-05 11:51:38 -05002442 struct _ddebug *debug;
Rusty Russell5e458cc2008-10-22 10:00:13 -05002443 unsigned int num_debug;
2444
Rusty Russell5e458cc2008-10-22 10:00:13 -05002445 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2446 sizeof(*debug), &num_debug);
Jason Barone9d376f2009-02-05 11:51:38 -05002447 if (debug)
2448 dynamic_debug_setup(debug, num_debug);
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04002449 }
Steven Rostedt90d595f2008-08-14 15:45:09 -04002450
Linus Torvalds1da177e2005-04-16 15:20:36 -07002451 err = module_finalize(hdr, sechdrs, mod);
2452 if (err < 0)
2453 goto cleanup;
2454
Thomas Koeller378bac82005-09-06 15:17:11 -07002455 /* flush the icache in correct context */
2456 old_fs = get_fs();
2457 set_fs(KERNEL_DS);
2458
2459 /*
2460 * Flush the instruction cache, since we've played with text.
2461 * Do it before processing of module parameters, so the module
2462 * can provide parameter accessor functions of its own.
2463 */
2464 if (mod->module_init)
2465 flush_icache_range((unsigned long)mod->module_init,
2466 (unsigned long)mod->module_init
2467 + mod->init_size);
2468 flush_icache_range((unsigned long)mod->module_core,
2469 (unsigned long)mod->module_core + mod->core_size);
2470
2471 set_fs(old_fs);
2472
Linus Torvalds1da177e2005-04-16 15:20:36 -07002473 mod->args = args;
Rusty Russell5e458cc2008-10-22 10:00:13 -05002474 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
Rusty Russell8d3b33f2006-03-25 03:07:05 -08002475 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2476 mod->name);
2477
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002478 /* Now sew it into the lists so we can get lockdep and oops
Andi Kleend72b3752008-08-30 10:09:00 +02002479 * info during argument parsing. Noone should access us, since
2480 * strong_try_module_get() will fail.
2481 * lockdep/oops can run asynchronous, so use the RCU list insertion
2482 * function to insert in a way safe to concurrent readers.
2483 * The mutex protects against concurrent writers.
2484 */
2485 list_add_rcu(&mod->list, &modules);
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002486
Rusty Russelle180a6b2009-03-31 13:05:29 -06002487 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002488 if (err < 0)
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002489 goto unlink;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002490
Rusty Russelle180a6b2009-03-31 13:05:29 -06002491 err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002492 if (err < 0)
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002493 goto unlink;
Rusty Russell80a3d1b2010-06-05 11:17:36 -06002494
Linus Torvalds1da177e2005-04-16 15:20:36 -07002495 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
Roland McGrath6d760132007-10-16 23:26:40 -07002496 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002497
2498 /* Get rid of temporary copy */
2499 vfree(hdr);
2500
Li Zefan7ead8b82009-08-17 16:56:28 +08002501 trace_module_load(mod);
2502
Linus Torvalds1da177e2005-04-16 15:20:36 -07002503 /* Done! */
2504 return mod;
2505
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002506 unlink:
Rusty Russelle91defa2009-03-31 13:05:35 -06002507 /* Unlink carefully: kallsyms could be walking list. */
2508 list_del_rcu(&mod->list);
2509 synchronize_sched();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002510 module_arch_cleanup(mod);
2511 cleanup:
Rusty Russella263f772009-09-25 00:32:58 -06002512 free_modinfo(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002513 module_unload_free(mod);
Christoph Lametere1783a22010-01-05 15:34:50 +09002514#if defined(CONFIG_MODULE_UNLOAD)
2515 free_percpu(mod->refptr);
Rusty Russellffa9f122009-09-25 00:32:59 -06002516 free_init:
Eric Dumazet720eba32009-02-03 13:31:36 +10302517#endif
Masami Hiramatsu6e2b7572009-03-16 18:13:36 -04002518 module_free(mod, mod->module_init);
2519 free_core:
2520 module_free(mod, mod->module_core);
2521 /* mod will be freed with core. Don't access it beyond this line! */
2522 free_percpu:
Rusty Russell293a7cf2010-05-31 19:53:50 +09302523 free_percpu(percpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002524 free_mod:
2525 kfree(args);
Jan Beulich554bdfe2009-07-06 14:51:44 +01002526 kfree(strmap);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002527 free_hdr:
2528 vfree(hdr);
Jayachandran C6fe2e702006-01-06 00:19:54 -08002529 return ERR_PTR(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002530
2531 truncated:
2532 printk(KERN_ERR "Module len %lu truncated\n", len);
2533 err = -ENOEXEC;
2534 goto free_hdr;
2535}
2536
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -07002537/* Call module constructors. */
2538static void do_mod_ctors(struct module *mod)
2539{
2540#ifdef CONFIG_CONSTRUCTORS
2541 unsigned long i;
2542
2543 for (i = 0; i < mod->num_ctors; i++)
2544 mod->ctors[i]();
2545#endif
2546}
2547
Linus Torvalds1da177e2005-04-16 15:20:36 -07002548/* This is where the real work happens */
Heiko Carstens17da2bd2009-01-14 14:14:10 +01002549SYSCALL_DEFINE3(init_module, void __user *, umod,
2550 unsigned long, len, const char __user *, uargs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002551{
2552 struct module *mod;
2553 int ret = 0;
2554
2555 /* Must have permission */
Kees Cook3d433212009-04-02 15:49:29 -07002556 if (!capable(CAP_SYS_MODULE) || modules_disabled)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002557 return -EPERM;
2558
2559 /* Only one module load at a time, please */
Ashutosh Naik6389a382006-03-23 03:00:46 -08002560 if (mutex_lock_interruptible(&module_mutex) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002561 return -EINTR;
2562
2563 /* Do all the hard work */
2564 mod = load_module(umod, len, uargs);
2565 if (IS_ERR(mod)) {
Ashutosh Naik6389a382006-03-23 03:00:46 -08002566 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002567 return PTR_ERR(mod);
2568 }
2569
Linus Torvalds1da177e2005-04-16 15:20:36 -07002570 /* Drop lock so they can recurse */
Ashutosh Naik6389a382006-03-23 03:00:46 -08002571 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002572
Alan Sterne041c682006-03-27 01:16:30 -08002573 blocking_notifier_call_chain(&module_notify_list,
2574 MODULE_STATE_COMING, mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002575
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -07002576 do_mod_ctors(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002577 /* Start the module */
2578 if (mod->init != NULL)
Arjan van de Ven59f94152008-07-30 12:49:02 -07002579 ret = do_one_initcall(mod->init);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002580 if (ret < 0) {
2581 /* Init routine failed: abort. Try to protect us from
2582 buggy refcounters. */
2583 mod->state = MODULE_STATE_GOING;
Paul E. McKenneyfbd568a3e2005-05-01 08:59:04 -07002584 synchronize_sched();
Rusty Russellaf49d922007-10-16 23:26:27 -07002585 module_put(mod);
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +02002586 blocking_notifier_call_chain(&module_notify_list,
2587 MODULE_STATE_GOING, mod);
Rusty Russellaf49d922007-10-16 23:26:27 -07002588 mutex_lock(&module_mutex);
2589 free_module(mod);
2590 mutex_unlock(&module_mutex);
Rusty Russellc9a3ba52008-01-29 17:13:18 -05002591 wake_up(&module_wq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002592 return ret;
2593 }
Alexey Dobriyane24e2e62008-03-10 11:43:53 -07002594 if (ret > 0) {
Joe Perchesad361c92009-07-06 13:05:40 -07002595 printk(KERN_WARNING
2596"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2597"%s: loading module anyway...\n",
Alexey Dobriyane24e2e62008-03-10 11:43:53 -07002598 __func__, mod->name, ret,
2599 __func__);
2600 dump_stack();
2601 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002602
Rusty Russell6c5db222008-03-10 11:43:52 -07002603 /* Now it's a first class citizen! Wake up anyone waiting for it. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002604 mod->state = MODULE_STATE_LIVE;
Rusty Russell6c5db222008-03-10 11:43:52 -07002605 wake_up(&module_wq);
Masami Hiramatsu0deddf432009-01-06 14:41:54 -08002606 blocking_notifier_call_chain(&module_notify_list,
2607 MODULE_STATE_LIVE, mod);
Rusty Russell6c5db222008-03-10 11:43:52 -07002608
Linus Torvaldsd6de2c82009-04-10 12:17:41 -07002609 /* We need to finish all async code before the module init sequence is done */
2610 async_synchronize_full();
2611
Rusty Russell6c5db222008-03-10 11:43:52 -07002612 mutex_lock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002613 /* Drop initial reference. */
2614 module_put(mod);
Rusty Russellad6561d2009-06-12 21:47:03 -06002615 trim_init_extable(mod);
Jan Beulich4a496222009-07-06 14:50:42 +01002616#ifdef CONFIG_KALLSYMS
2617 mod->num_symtab = mod->core_num_syms;
2618 mod->symtab = mod->core_symtab;
Jan Beulich554bdfe2009-07-06 14:51:44 +01002619 mod->strtab = mod->core_strtab;
Jan Beulich4a496222009-07-06 14:50:42 +01002620#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002621 module_free(mod, mod->module_init);
2622 mod->module_init = NULL;
2623 mod->init_size = 0;
2624 mod->init_text_size = 0;
Ashutosh Naik6389a382006-03-23 03:00:46 -08002625 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002626
2627 return 0;
2628}
2629
2630static inline int within(unsigned long addr, void *start, unsigned long size)
2631{
2632 return ((void *)addr >= start && (void *)addr < start + size);
2633}
2634
2635#ifdef CONFIG_KALLSYMS
2636/*
2637 * This ignores the intensely annoying "mapping symbols" found
2638 * in ARM ELF files: $a, $t and $d.
2639 */
2640static inline int is_arm_mapping_symbol(const char *str)
2641{
Daniel Walker22a8bde2007-10-18 03:06:07 -07002642 return str[0] == '$' && strchr("atd", str[1])
Linus Torvalds1da177e2005-04-16 15:20:36 -07002643 && (str[2] == '\0' || str[2] == '.');
2644}
2645
2646static const char *get_ksymbol(struct module *mod,
2647 unsigned long addr,
2648 unsigned long *size,
2649 unsigned long *offset)
2650{
2651 unsigned int i, best = 0;
2652 unsigned long nextval;
2653
2654 /* At worse, next value is at end of module */
Masami Hiramatsua06f6212009-01-06 14:41:49 -08002655 if (within_module_init(addr, mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002656 nextval = (unsigned long)mod->module_init+mod->init_text_size;
Daniel Walker22a8bde2007-10-18 03:06:07 -07002657 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07002658 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2659
2660 /* Scan for closest preceeding symbol, and next symbol. (ELF
Daniel Walker22a8bde2007-10-18 03:06:07 -07002661 starts real symbols at 1). */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002662 for (i = 1; i < mod->num_symtab; i++) {
2663 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2664 continue;
2665
2666 /* We ignore unnamed symbols: they're uninformative
2667 * and inserted at a whim. */
2668 if (mod->symtab[i].st_value <= addr
2669 && mod->symtab[i].st_value > mod->symtab[best].st_value
2670 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2671 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2672 best = i;
2673 if (mod->symtab[i].st_value > addr
2674 && mod->symtab[i].st_value < nextval
2675 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2676 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2677 nextval = mod->symtab[i].st_value;
2678 }
2679
2680 if (!best)
2681 return NULL;
2682
Alexey Dobriyanffb45122007-05-08 00:28:41 -07002683 if (size)
2684 *size = nextval - mod->symtab[best].st_value;
2685 if (offset)
2686 *offset = addr - mod->symtab[best].st_value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002687 return mod->strtab + mod->symtab[best].st_name;
2688}
2689
Rusty Russell6dd06c92008-01-29 17:13:22 -05002690/* For kallsyms to ask for address resolution. NULL means not found. Careful
2691 * not to lock to avoid deadlock on oopses, simply disable preemption. */
Andrew Morton92dfc9d2008-02-08 04:18:43 -08002692const char *module_address_lookup(unsigned long addr,
Rusty Russell6dd06c92008-01-29 17:13:22 -05002693 unsigned long *size,
2694 unsigned long *offset,
2695 char **modname,
2696 char *namebuf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002697{
2698 struct module *mod;
Rusty Russellcb2a5202008-01-14 00:55:03 -08002699 const char *ret = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002700
Rusty Russellcb2a5202008-01-14 00:55:03 -08002701 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02002702 list_for_each_entry_rcu(mod, &modules, list) {
Masami Hiramatsua06f6212009-01-06 14:41:49 -08002703 if (within_module_init(addr, mod) ||
2704 within_module_core(addr, mod)) {
Franck Bui-Huuffc50892006-10-03 01:13:48 -07002705 if (modname)
2706 *modname = mod->name;
Rusty Russellcb2a5202008-01-14 00:55:03 -08002707 ret = get_ksymbol(mod, addr, size, offset);
2708 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002709 }
2710 }
Rusty Russell6dd06c92008-01-29 17:13:22 -05002711 /* Make a copy in here where it's safe */
2712 if (ret) {
2713 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2714 ret = namebuf;
2715 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08002716 preempt_enable();
Andrew Morton92dfc9d2008-02-08 04:18:43 -08002717 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002718}
2719
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07002720int lookup_module_symbol_name(unsigned long addr, char *symname)
2721{
2722 struct module *mod;
2723
Rusty Russellcb2a5202008-01-14 00:55:03 -08002724 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02002725 list_for_each_entry_rcu(mod, &modules, list) {
Masami Hiramatsua06f6212009-01-06 14:41:49 -08002726 if (within_module_init(addr, mod) ||
2727 within_module_core(addr, mod)) {
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07002728 const char *sym;
2729
2730 sym = get_ksymbol(mod, addr, NULL, NULL);
2731 if (!sym)
2732 goto out;
Tejun Heo9281ace2007-07-17 04:03:51 -07002733 strlcpy(symname, sym, KSYM_NAME_LEN);
Rusty Russellcb2a5202008-01-14 00:55:03 -08002734 preempt_enable();
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07002735 return 0;
2736 }
2737 }
2738out:
Rusty Russellcb2a5202008-01-14 00:55:03 -08002739 preempt_enable();
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07002740 return -ERANGE;
2741}
2742
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002743int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2744 unsigned long *offset, char *modname, char *name)
2745{
2746 struct module *mod;
2747
Rusty Russellcb2a5202008-01-14 00:55:03 -08002748 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02002749 list_for_each_entry_rcu(mod, &modules, list) {
Masami Hiramatsua06f6212009-01-06 14:41:49 -08002750 if (within_module_init(addr, mod) ||
2751 within_module_core(addr, mod)) {
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002752 const char *sym;
2753
2754 sym = get_ksymbol(mod, addr, size, offset);
2755 if (!sym)
2756 goto out;
2757 if (modname)
Tejun Heo9281ace2007-07-17 04:03:51 -07002758 strlcpy(modname, mod->name, MODULE_NAME_LEN);
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002759 if (name)
Tejun Heo9281ace2007-07-17 04:03:51 -07002760 strlcpy(name, sym, KSYM_NAME_LEN);
Rusty Russellcb2a5202008-01-14 00:55:03 -08002761 preempt_enable();
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002762 return 0;
2763 }
2764 }
2765out:
Rusty Russellcb2a5202008-01-14 00:55:03 -08002766 preempt_enable();
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002767 return -ERANGE;
2768}
2769
Alexey Dobriyanea078902007-05-08 00:28:39 -07002770int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2771 char *name, char *module_name, int *exported)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002772{
2773 struct module *mod;
2774
Rusty Russellcb2a5202008-01-14 00:55:03 -08002775 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02002776 list_for_each_entry_rcu(mod, &modules, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002777 if (symnum < mod->num_symtab) {
2778 *value = mod->symtab[symnum].st_value;
2779 *type = mod->symtab[symnum].st_info;
Andreas Gruenbacher098c5ee2006-07-14 00:24:04 -07002780 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
Tejun Heo9281ace2007-07-17 04:03:51 -07002781 KSYM_NAME_LEN);
2782 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
Tim Abbottca4787b2009-01-05 08:40:10 -06002783 *exported = is_exported(name, *value, mod);
Rusty Russellcb2a5202008-01-14 00:55:03 -08002784 preempt_enable();
Alexey Dobriyanea078902007-05-08 00:28:39 -07002785 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002786 }
2787 symnum -= mod->num_symtab;
2788 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08002789 preempt_enable();
Alexey Dobriyanea078902007-05-08 00:28:39 -07002790 return -ERANGE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002791}
2792
2793static unsigned long mod_find_symname(struct module *mod, const char *name)
2794{
2795 unsigned int i;
2796
2797 for (i = 0; i < mod->num_symtab; i++)
Keith Owens54e8ce42006-02-03 03:03:53 -08002798 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2799 mod->symtab[i].st_info != 'U')
Linus Torvalds1da177e2005-04-16 15:20:36 -07002800 return mod->symtab[i].st_value;
2801 return 0;
2802}
2803
2804/* Look for this name: can be of form module:name. */
2805unsigned long module_kallsyms_lookup_name(const char *name)
2806{
2807 struct module *mod;
2808 char *colon;
2809 unsigned long ret = 0;
2810
2811 /* Don't lock: we're in enough trouble already. */
Rusty Russellcb2a5202008-01-14 00:55:03 -08002812 preempt_disable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002813 if ((colon = strchr(name, ':')) != NULL) {
2814 *colon = '\0';
2815 if ((mod = find_module(name)) != NULL)
2816 ret = mod_find_symname(mod, colon+1);
2817 *colon = ':';
2818 } else {
Andi Kleend72b3752008-08-30 10:09:00 +02002819 list_for_each_entry_rcu(mod, &modules, list)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002820 if ((ret = mod_find_symname(mod, name)) != 0)
2821 break;
2822 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08002823 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002824 return ret;
2825}
Anders Kaseorg75a66612008-12-05 19:03:58 -05002826
2827int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2828 struct module *, unsigned long),
2829 void *data)
2830{
2831 struct module *mod;
2832 unsigned int i;
2833 int ret;
2834
2835 list_for_each_entry(mod, &modules, list) {
2836 for (i = 0; i < mod->num_symtab; i++) {
2837 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2838 mod, mod->symtab[i].st_value);
2839 if (ret != 0)
2840 return ret;
2841 }
2842 }
2843 return 0;
2844}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002845#endif /* CONFIG_KALLSYMS */
2846
Arjan van de Ven21aa9282008-01-25 21:08:33 +01002847static char *module_flags(struct module *mod, char *buf)
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002848{
2849 int bx = 0;
2850
Arjan van de Ven21aa9282008-01-25 21:08:33 +01002851 if (mod->taints ||
2852 mod->state == MODULE_STATE_GOING ||
2853 mod->state == MODULE_STATE_COMING) {
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002854 buf[bx++] = '(';
Andi Kleen25ddbb12008-10-15 22:01:41 -07002855 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002856 buf[bx++] = 'P';
Andi Kleen25ddbb12008-10-15 22:01:41 -07002857 if (mod->taints & (1 << TAINT_FORCED_MODULE))
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002858 buf[bx++] = 'F';
Linus Torvalds26e9a392008-10-17 09:50:12 -07002859 if (mod->taints & (1 << TAINT_CRAP))
Greg Kroah-Hartman061b1bd2008-09-24 14:46:44 -07002860 buf[bx++] = 'C';
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002861 /*
2862 * TAINT_FORCED_RMMOD: could be added.
2863 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2864 * apply to modules.
2865 */
Arjan van de Ven21aa9282008-01-25 21:08:33 +01002866
2867 /* Show a - for module-is-being-unloaded */
2868 if (mod->state == MODULE_STATE_GOING)
2869 buf[bx++] = '-';
2870 /* Show a + for module-is-being-loaded */
2871 if (mod->state == MODULE_STATE_COMING)
2872 buf[bx++] = '+';
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002873 buf[bx++] = ')';
2874 }
2875 buf[bx] = '\0';
2876
2877 return buf;
2878}
2879
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04002880#ifdef CONFIG_PROC_FS
2881/* Called by the /proc file system to return a list of modules. */
2882static void *m_start(struct seq_file *m, loff_t *pos)
2883{
2884 mutex_lock(&module_mutex);
2885 return seq_list_start(&modules, *pos);
2886}
2887
2888static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2889{
2890 return seq_list_next(p, &modules, pos);
2891}
2892
2893static void m_stop(struct seq_file *m, void *p)
2894{
2895 mutex_unlock(&module_mutex);
2896}
2897
Linus Torvalds1da177e2005-04-16 15:20:36 -07002898static int m_show(struct seq_file *m, void *p)
2899{
2900 struct module *mod = list_entry(p, struct module, list);
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002901 char buf[8];
2902
Denys Vlasenko2f0f2a32008-07-22 19:24:27 -05002903 seq_printf(m, "%s %u",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002904 mod->name, mod->init_size + mod->core_size);
2905 print_unload_info(m, mod);
2906
2907 /* Informative for users. */
2908 seq_printf(m, " %s",
2909 mod->state == MODULE_STATE_GOING ? "Unloading":
2910 mod->state == MODULE_STATE_COMING ? "Loading":
2911 "Live");
2912 /* Used by oprofile and other similar tools. */
2913 seq_printf(m, " 0x%p", mod->module_core);
2914
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002915 /* Taints info */
2916 if (mod->taints)
Arjan van de Ven21aa9282008-01-25 21:08:33 +01002917 seq_printf(m, " %s", module_flags(mod, buf));
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002918
Linus Torvalds1da177e2005-04-16 15:20:36 -07002919 seq_printf(m, "\n");
2920 return 0;
2921}
2922
2923/* Format: modulename size refcount deps address
2924
2925 Where refcount is a number or -, and deps is a comma-separated list
2926 of depends or -.
2927*/
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04002928static const struct seq_operations modules_op = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002929 .start = m_start,
2930 .next = m_next,
2931 .stop = m_stop,
2932 .show = m_show
2933};
2934
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04002935static int modules_open(struct inode *inode, struct file *file)
2936{
2937 return seq_open(file, &modules_op);
2938}
2939
2940static const struct file_operations proc_modules_operations = {
2941 .open = modules_open,
2942 .read = seq_read,
2943 .llseek = seq_lseek,
2944 .release = seq_release,
2945};
2946
2947static int __init proc_modules_init(void)
2948{
2949 proc_create("modules", 0, NULL, &proc_modules_operations);
2950 return 0;
2951}
2952module_init(proc_modules_init);
2953#endif
2954
Linus Torvalds1da177e2005-04-16 15:20:36 -07002955/* Given an address, look for it in the module exception tables. */
2956const struct exception_table_entry *search_module_extables(unsigned long addr)
2957{
Linus Torvalds1da177e2005-04-16 15:20:36 -07002958 const struct exception_table_entry *e = NULL;
2959 struct module *mod;
2960
Rusty Russell24da1cb2007-07-15 23:41:46 -07002961 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02002962 list_for_each_entry_rcu(mod, &modules, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002963 if (mod->num_exentries == 0)
2964 continue;
Daniel Walker22a8bde2007-10-18 03:06:07 -07002965
Linus Torvalds1da177e2005-04-16 15:20:36 -07002966 e = search_extable(mod->extable,
2967 mod->extable + mod->num_exentries - 1,
2968 addr);
2969 if (e)
2970 break;
2971 }
Rusty Russell24da1cb2007-07-15 23:41:46 -07002972 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002973
2974 /* Now, if we found one, we are running inside it now, hence
Daniel Walker22a8bde2007-10-18 03:06:07 -07002975 we cannot unload the module, hence no refcnt needed. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002976 return e;
2977}
2978
Ingo Molnar4d435f92006-07-03 00:24:24 -07002979/*
Rusty Russelle6104992009-03-31 13:05:31 -06002980 * is_module_address - is this address inside a module?
2981 * @addr: the address to check.
2982 *
2983 * See is_module_text_address() if you simply want to see if the address
2984 * is code (not data).
Ingo Molnar4d435f92006-07-03 00:24:24 -07002985 */
Rusty Russelle6104992009-03-31 13:05:31 -06002986bool is_module_address(unsigned long addr)
Ingo Molnar4d435f92006-07-03 00:24:24 -07002987{
Rusty Russelle6104992009-03-31 13:05:31 -06002988 bool ret;
Ingo Molnar4d435f92006-07-03 00:24:24 -07002989
Rusty Russell24da1cb2007-07-15 23:41:46 -07002990 preempt_disable();
Rusty Russelle6104992009-03-31 13:05:31 -06002991 ret = __module_address(addr) != NULL;
Rusty Russell24da1cb2007-07-15 23:41:46 -07002992 preempt_enable();
Ingo Molnar4d435f92006-07-03 00:24:24 -07002993
Rusty Russelle6104992009-03-31 13:05:31 -06002994 return ret;
Ingo Molnar4d435f92006-07-03 00:24:24 -07002995}
2996
Rusty Russelle6104992009-03-31 13:05:31 -06002997/*
2998 * __module_address - get the module which contains an address.
2999 * @addr: the address.
3000 *
3001 * Must be called with preempt disabled or module mutex held so that
3002 * module doesn't get freed during this.
3003 */
Linus Torvalds714f83d2009-04-05 11:04:19 -07003004struct module *__module_address(unsigned long addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003005{
3006 struct module *mod;
3007
Rusty Russell3a642e92008-07-22 19:24:28 -05003008 if (addr < module_addr_min || addr > module_addr_max)
3009 return NULL;
3010
Andi Kleend72b3752008-08-30 10:09:00 +02003011 list_for_each_entry_rcu(mod, &modules, list)
Rusty Russelle6104992009-03-31 13:05:31 -06003012 if (within_module_core(addr, mod)
3013 || within_module_init(addr, mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003014 return mod;
3015 return NULL;
3016}
Tim Abbottc6b37802008-12-05 19:03:59 -05003017EXPORT_SYMBOL_GPL(__module_address);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003018
Rusty Russelle6104992009-03-31 13:05:31 -06003019/*
3020 * is_module_text_address - is this address inside module code?
3021 * @addr: the address to check.
3022 *
3023 * See is_module_address() if you simply want to see if the address is
3024 * anywhere in a module. See kernel_text_address() for testing if an
3025 * address corresponds to kernel or module code.
3026 */
3027bool is_module_text_address(unsigned long addr)
3028{
3029 bool ret;
3030
3031 preempt_disable();
3032 ret = __module_text_address(addr) != NULL;
3033 preempt_enable();
3034
3035 return ret;
3036}
3037
3038/*
3039 * __module_text_address - get the module whose code contains an address.
3040 * @addr: the address.
3041 *
3042 * Must be called with preempt disabled or module mutex held so that
3043 * module doesn't get freed during this.
3044 */
3045struct module *__module_text_address(unsigned long addr)
3046{
3047 struct module *mod = __module_address(addr);
3048 if (mod) {
3049 /* Make sure it's within the text section. */
3050 if (!within(addr, mod->module_init, mod->init_text_size)
3051 && !within(addr, mod->module_core, mod->core_text_size))
3052 mod = NULL;
3053 }
3054 return mod;
3055}
Tim Abbottc6b37802008-12-05 19:03:59 -05003056EXPORT_SYMBOL_GPL(__module_text_address);
Rusty Russelle6104992009-03-31 13:05:31 -06003057
Linus Torvalds1da177e2005-04-16 15:20:36 -07003058/* Don't grab lock, we're oopsing. */
3059void print_modules(void)
3060{
3061 struct module *mod;
Randy Dunlap2bc2d612006-10-02 02:17:02 -07003062 char buf[8];
Linus Torvalds1da177e2005-04-16 15:20:36 -07003063
Linus Torvaldsb2311252009-06-16 11:07:14 -07003064 printk(KERN_DEFAULT "Modules linked in:");
Andi Kleend72b3752008-08-30 10:09:00 +02003065 /* Most callers should already have preempt disabled, but make sure */
3066 preempt_disable();
3067 list_for_each_entry_rcu(mod, &modules, list)
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003068 printk(" %s%s", mod->name, module_flags(mod, buf));
Andi Kleend72b3752008-08-30 10:09:00 +02003069 preempt_enable();
Arjan van de Vene14af7e2008-01-25 21:08:33 +01003070 if (last_unloaded_module[0])
3071 printk(" [last unloaded: %s]", last_unloaded_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003072 printk("\n");
3073}
3074
Linus Torvalds1da177e2005-04-16 15:20:36 -07003075#ifdef CONFIG_MODVERSIONS
Rusty Russell8c8ef422009-03-31 13:05:34 -06003076/* Generate the signature for all relevant module structures here.
3077 * If these change, we don't want to try to parse the module. */
3078void module_layout(struct module *mod,
3079 struct modversion_info *ver,
3080 struct kernel_param *kp,
3081 struct kernel_symbol *ks,
Rusty Russell8c8ef422009-03-31 13:05:34 -06003082 struct tracepoint *tp)
3083{
3084}
3085EXPORT_SYMBOL(module_layout);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003086#endif
Mathieu Desnoyers8256e472007-10-18 23:41:06 -07003087
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04003088#ifdef CONFIG_TRACEPOINTS
3089void module_update_tracepoints(void)
3090{
3091 struct module *mod;
3092
3093 mutex_lock(&module_mutex);
3094 list_for_each_entry(mod, &modules, list)
3095 if (!mod->taints)
3096 tracepoint_update_probe_range(mod->tracepoints,
3097 mod->tracepoints + mod->num_tracepoints);
3098 mutex_unlock(&module_mutex);
3099}
3100
3101/*
3102 * Returns 0 if current not found.
3103 * Returns 1 if current found.
3104 */
3105int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3106{
3107 struct module *iter_mod;
3108 int found = 0;
3109
3110 mutex_lock(&module_mutex);
3111 list_for_each_entry(iter_mod, &modules, list) {
3112 if (!iter_mod->taints) {
3113 /*
3114 * Sorted module list
3115 */
3116 if (iter_mod < iter->module)
3117 continue;
3118 else if (iter_mod > iter->module)
3119 iter->tracepoint = NULL;
3120 found = tracepoint_get_iter_range(&iter->tracepoint,
3121 iter_mod->tracepoints,
3122 iter_mod->tracepoints
3123 + iter_mod->num_tracepoints);
3124 if (found) {
3125 iter->module = iter_mod;
3126 break;
3127 }
3128 }
3129 }
3130 mutex_unlock(&module_mutex);
3131 return found;
3132}
3133#endif