blob: e7e25a86bbff4db87a8ef6f3039b80cd272369b9 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/binfmt_elf.c
3 *
4 * These are the functions used to load ELF format executables as used
5 * on SVr4 machines. Information on the format may be found in the book
6 * "UNIX SYSTEM V RELEASE 4 Programmers Guide: Ansi C and Programming Support
7 * Tools".
8 *
9 * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com).
10 */
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/mm.h>
16#include <linux/mman.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/errno.h>
18#include <linux/signal.h>
19#include <linux/binfmts.h>
20#include <linux/string.h>
21#include <linux/file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/personality.h>
24#include <linux/elfcore.h>
25#include <linux/init.h>
26#include <linux/highuid.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/compiler.h>
28#include <linux/highmem.h>
29#include <linux/pagemap.h>
Denys Vlasenko2aa362c2012-10-04 17:15:36 -070030#include <linux/vmalloc.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <linux/security.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include <linux/random.h>
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070033#include <linux/elf.h>
Kees Cookd1fd8362015-04-14 15:48:07 -070034#include <linux/elf-randomize.h>
Alexey Dobriyan7e80d0d2007-05-08 00:28:59 -070035#include <linux/utsname.h>
Daisuke HATAYAMA088e7af2010-03-05 13:44:06 -080036#include <linux/coredump.h>
Frederic Weisbecker6fac4822012-11-13 14:20:55 +010037#include <linux/sched.h>
Ross Zwisler50378352015-10-05 16:33:36 -060038#include <linux/dax.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include <asm/uaccess.h>
40#include <asm/param.h>
41#include <asm/page.h>
42
Denys Vlasenko2aa362c2012-10-04 17:15:36 -070043#ifndef user_long_t
44#define user_long_t long
45#endif
Denys Vlasenko49ae4d42012-10-04 17:15:35 -070046#ifndef user_siginfo_t
47#define user_siginfo_t siginfo_t
48#endif
49
Al Viro71613c32012-10-20 22:00:48 -040050static int load_elf_binary(struct linux_binprm *bprm);
Andrew Mortonbb1ad822008-01-30 13:31:07 +010051static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *,
52 int, int, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
Josh Triplett69369a72014-04-03 14:48:27 -070054#ifdef CONFIG_USELIB
55static int load_elf_library(struct file *);
56#else
57#define load_elf_library NULL
58#endif
59
Linus Torvalds1da177e2005-04-16 15:20:36 -070060/*
61 * If we don't support core dumping, then supply a NULL so we
62 * don't even try.
63 */
Christoph Hellwig698ba7b2009-12-15 16:47:37 -080064#ifdef CONFIG_ELF_CORE
Masami Hiramatsuf6151df2009-12-17 15:27:16 -080065static int elf_core_dump(struct coredump_params *cprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -070066#else
67#define elf_core_dump NULL
68#endif
69
70#if ELF_EXEC_PAGESIZE > PAGE_SIZE
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070071#define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
Linus Torvalds1da177e2005-04-16 15:20:36 -070072#else
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070073#define ELF_MIN_ALIGN PAGE_SIZE
Linus Torvalds1da177e2005-04-16 15:20:36 -070074#endif
75
76#ifndef ELF_CORE_EFLAGS
77#define ELF_CORE_EFLAGS 0
78#endif
79
80#define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
81#define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
82#define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
83
84static struct linux_binfmt elf_format = {
Mikael Petterssonf670d0e2011-01-12 17:00:02 -080085 .module = THIS_MODULE,
86 .load_binary = load_elf_binary,
87 .load_shlib = load_elf_library,
88 .core_dump = elf_core_dump,
89 .min_coredump = ELF_EXEC_PAGESIZE,
Linus Torvalds1da177e2005-04-16 15:20:36 -070090};
91
Andrew Mortond4e3cc32007-07-21 04:37:32 -070092#define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
Linus Torvalds1da177e2005-04-16 15:20:36 -070093
94static int set_brk(unsigned long start, unsigned long end)
95{
96 start = ELF_PAGEALIGN(start);
97 end = ELF_PAGEALIGN(end);
98 if (end > start) {
Linus Torvalds5d22fc22016-05-27 15:57:31 -070099 int error = vm_brk(start, end - start);
100 if (error)
101 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 }
103 current->mm->start_brk = current->mm->brk = end;
104 return 0;
105}
106
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107/* We need to explicitly zero any fractional pages
108 after the data section (i.e. bss). This would
109 contain the junk from the file that should not
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700110 be in memory
111 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112static int padzero(unsigned long elf_bss)
113{
114 unsigned long nbyte;
115
116 nbyte = ELF_PAGEOFFSET(elf_bss);
117 if (nbyte) {
118 nbyte = ELF_MIN_ALIGN - nbyte;
119 if (clear_user((void __user *) elf_bss, nbyte))
120 return -EFAULT;
121 }
122 return 0;
123}
124
Ohad Ben-Cohen09c6dd32008-02-03 18:05:15 +0200125/* Let's use some macros to make this stack manipulation a little clearer */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126#ifdef CONFIG_STACK_GROWSUP
127#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
128#define STACK_ROUND(sp, items) \
129 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700130#define STACK_ALLOC(sp, len) ({ \
131 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
132 old_sp; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133#else
134#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
135#define STACK_ROUND(sp, items) \
136 (((unsigned long) (sp - items)) &~ 15UL)
137#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
138#endif
139
Nathan Lynch483fad12008-07-22 04:48:46 +1000140#ifndef ELF_BASE_PLATFORM
141/*
142 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
143 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
144 * will be copied to the user stack in the same manner as AT_PLATFORM.
145 */
146#define ELF_BASE_PLATFORM NULL
147#endif
148
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149static int
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700150create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
Andi Kleend20894a2008-02-08 04:21:54 -0800151 unsigned long load_addr, unsigned long interp_load_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152{
153 unsigned long p = bprm->p;
154 int argc = bprm->argc;
155 int envc = bprm->envc;
156 elf_addr_t __user *argv;
157 elf_addr_t __user *envp;
158 elf_addr_t __user *sp;
159 elf_addr_t __user *u_platform;
Nathan Lynch483fad12008-07-22 04:48:46 +1000160 elf_addr_t __user *u_base_platform;
Kees Cookf06295b2009-01-07 18:08:52 -0800161 elf_addr_t __user *u_rand_bytes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 const char *k_platform = ELF_PLATFORM;
Nathan Lynch483fad12008-07-22 04:48:46 +1000163 const char *k_base_platform = ELF_BASE_PLATFORM;
Kees Cookf06295b2009-01-07 18:08:52 -0800164 unsigned char k_rand_bytes[16];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165 int items;
166 elf_addr_t *elf_info;
167 int ei_index = 0;
David Howells86a264a2008-11-14 10:39:18 +1100168 const struct cred *cred = current_cred();
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700169 struct vm_area_struct *vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170
171 /*
Franck Bui-Huud68c9d62007-10-16 23:30:24 -0700172 * In some cases (e.g. Hyper-Threading), we want to avoid L1
173 * evictions by the processes running on the same package. One
174 * thing we can do is to shuffle the initial stack for them.
175 */
176
177 p = arch_align_stack(p);
178
179 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 * If this architecture has a platform capability string, copy it
181 * to userspace. In some cases (Sparc), this info is impossible
182 * for userspace to get any other way, in others (i386) it is
183 * merely difficult.
184 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 u_platform = NULL;
186 if (k_platform) {
187 size_t len = strlen(k_platform) + 1;
188
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
190 if (__copy_to_user(u_platform, k_platform, len))
191 return -EFAULT;
192 }
193
Nathan Lynch483fad12008-07-22 04:48:46 +1000194 /*
195 * If this architecture has a "base" platform capability
196 * string, copy it to userspace.
197 */
198 u_base_platform = NULL;
199 if (k_base_platform) {
200 size_t len = strlen(k_base_platform) + 1;
201
202 u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
203 if (__copy_to_user(u_base_platform, k_base_platform, len))
204 return -EFAULT;
205 }
206
Kees Cookf06295b2009-01-07 18:08:52 -0800207 /*
208 * Generate 16 random bytes for userspace PRNG seeding.
209 */
210 get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
211 u_rand_bytes = (elf_addr_t __user *)
212 STACK_ALLOC(p, sizeof(k_rand_bytes));
213 if (__copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes)))
214 return -EFAULT;
215
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 /* Create the ELF interpreter info */
Jesper Juhl785d5572006-06-23 02:05:35 -0700217 elf_info = (elf_addr_t *)current->mm->saved_auxv;
Olaf Hering4f9a58d2007-10-16 23:30:12 -0700218 /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219#define NEW_AUX_ENT(id, val) \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700220 do { \
Jesper Juhl785d5572006-06-23 02:05:35 -0700221 elf_info[ei_index++] = id; \
222 elf_info[ei_index++] = val; \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700223 } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224
225#ifdef ARCH_DLINFO
226 /*
227 * ARCH_DLINFO must come first so PPC can do its special alignment of
228 * AUXV.
Olaf Hering4f9a58d2007-10-16 23:30:12 -0700229 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
230 * ARCH_DLINFO changes
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231 */
232 ARCH_DLINFO;
233#endif
234 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
235 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
236 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
237 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700238 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
240 NEW_AUX_ENT(AT_BASE, interp_load_addr);
241 NEW_AUX_ENT(AT_FLAGS, 0);
242 NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
Eric W. Biedermanebc887b2012-02-07 18:36:10 -0800243 NEW_AUX_ENT(AT_UID, from_kuid_munged(cred->user_ns, cred->uid));
244 NEW_AUX_ENT(AT_EUID, from_kuid_munged(cred->user_ns, cred->euid));
245 NEW_AUX_ENT(AT_GID, from_kgid_munged(cred->user_ns, cred->gid));
246 NEW_AUX_ENT(AT_EGID, from_kgid_munged(cred->user_ns, cred->egid));
Jesper Juhl785d5572006-06-23 02:05:35 -0700247 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
Kees Cookf06295b2009-01-07 18:08:52 -0800248 NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
Michael Neuling21713642013-04-17 17:33:11 +0000249#ifdef ELF_HWCAP2
250 NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2);
251#endif
John Reiser65191082008-07-21 14:21:32 -0700252 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 if (k_platform) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700254 NEW_AUX_ENT(AT_PLATFORM,
Jesper Juhl785d5572006-06-23 02:05:35 -0700255 (elf_addr_t)(unsigned long)u_platform);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 }
Nathan Lynch483fad12008-07-22 04:48:46 +1000257 if (k_base_platform) {
258 NEW_AUX_ENT(AT_BASE_PLATFORM,
259 (elf_addr_t)(unsigned long)u_base_platform);
260 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
Jesper Juhl785d5572006-06-23 02:05:35 -0700262 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 }
264#undef NEW_AUX_ENT
265 /* AT_NULL is zero; clear the rest too */
266 memset(&elf_info[ei_index], 0,
267 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
268
269 /* And advance past the AT_NULL entry. */
270 ei_index += 2;
271
272 sp = STACK_ADD(p, ei_index);
273
Andi Kleend20894a2008-02-08 04:21:54 -0800274 items = (argc + 1) + (envc + 1) + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 bprm->p = STACK_ROUND(sp, items);
276
277 /* Point sp at the lowest address on the stack */
278#ifdef CONFIG_STACK_GROWSUP
279 sp = (elf_addr_t __user *)bprm->p - items - ei_index;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700280 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281#else
282 sp = (elf_addr_t __user *)bprm->p;
283#endif
284
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700285
286 /*
287 * Grow the stack manually; some architectures have a limit on how
288 * far ahead a user-space access may be in order to grow the stack.
289 */
290 vma = find_extend_vma(current->mm, bprm->p);
291 if (!vma)
292 return -EFAULT;
293
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 /* Now, let's put argc (and argv, envp if appropriate) on the stack */
295 if (__put_user(argc, sp++))
296 return -EFAULT;
Andi Kleend20894a2008-02-08 04:21:54 -0800297 argv = sp;
298 envp = argv + argc + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299
300 /* Populate argv and envp */
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -0700301 p = current->mm->arg_end = current->mm->arg_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 while (argc-- > 0) {
303 size_t len;
Heiko Carstens841d5fb2006-12-06 20:36:35 -0800304 if (__put_user((elf_addr_t)p, argv++))
305 return -EFAULT;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700306 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
307 if (!len || len > MAX_ARG_STRLEN)
WANG Cong23c49712008-05-08 21:52:33 +0800308 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 p += len;
310 }
311 if (__put_user(0, argv))
312 return -EFAULT;
313 current->mm->arg_end = current->mm->env_start = p;
314 while (envc-- > 0) {
315 size_t len;
Heiko Carstens841d5fb2006-12-06 20:36:35 -0800316 if (__put_user((elf_addr_t)p, envp++))
317 return -EFAULT;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700318 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
319 if (!len || len > MAX_ARG_STRLEN)
WANG Cong23c49712008-05-08 21:52:33 +0800320 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 p += len;
322 }
323 if (__put_user(0, envp))
324 return -EFAULT;
325 current->mm->env_end = p;
326
327 /* Put the elf_info on the stack in the right place. */
328 sp = (elf_addr_t __user *)envp + 1;
329 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
330 return -EFAULT;
331 return 0;
332}
333
James Hoganc07380b2011-05-09 10:58:40 +0100334#ifndef elf_map
335
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336static unsigned long elf_map(struct file *filep, unsigned long addr,
Jiri Kosinacc503c12008-01-30 13:31:07 +0100337 struct elf_phdr *eppnt, int prot, int type,
338 unsigned long total_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339{
340 unsigned long map_addr;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100341 unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
342 unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
343 addr = ELF_PAGESTART(addr);
344 size = ELF_PAGEALIGN(size);
Jan Kratochvil60bfba72007-07-15 23:40:06 -0700345
Andrew Mortond4e3cc32007-07-21 04:37:32 -0700346 /* mmap() will return -EINVAL if given a zero size, but a
347 * segment with zero filesize is perfectly valid */
Jiri Kosinacc503c12008-01-30 13:31:07 +0100348 if (!size)
349 return addr;
350
Jiri Kosinacc503c12008-01-30 13:31:07 +0100351 /*
352 * total_size is the size of the ELF (interpreter) image.
353 * The _first_ mmap needs to know the full size, otherwise
354 * randomization might put this image into an overlapping
355 * position with the ELF binary image. (since size < total_size)
356 * So we first map the 'big' image - and unmap the remainder at
357 * the end. (which unmap is needed for ELF images with holes.)
358 */
359 if (total_size) {
360 total_size = ELF_PAGEALIGN(total_size);
Al Viro5a5e4c22012-05-30 01:49:38 -0400361 map_addr = vm_mmap(filep, addr, total_size, prot, type, off);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100362 if (!BAD_ADDR(map_addr))
Al Viro5a5e4c22012-05-30 01:49:38 -0400363 vm_munmap(map_addr+size, total_size-size);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100364 } else
Al Viro5a5e4c22012-05-30 01:49:38 -0400365 map_addr = vm_mmap(filep, addr, size, prot, type, off);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100366
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 return(map_addr);
368}
369
James Hoganc07380b2011-05-09 10:58:40 +0100370#endif /* !elf_map */
371
Jiri Kosinacc503c12008-01-30 13:31:07 +0100372static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr)
373{
374 int i, first_idx = -1, last_idx = -1;
375
376 for (i = 0; i < nr; i++) {
377 if (cmds[i].p_type == PT_LOAD) {
378 last_idx = i;
379 if (first_idx == -1)
380 first_idx = i;
381 }
382 }
383 if (first_idx == -1)
384 return 0;
385
386 return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz -
387 ELF_PAGESTART(cmds[first_idx].p_vaddr);
388}
389
Paul Burton6a8d3892014-09-11 08:30:14 +0100390/**
391 * load_elf_phdrs() - load ELF program headers
392 * @elf_ex: ELF header of the binary whose program headers should be loaded
393 * @elf_file: the opened ELF binary file
394 *
395 * Loads ELF program headers from the binary file elf_file, which has the ELF
396 * header pointed to by elf_ex, into a newly allocated array. The caller is
397 * responsible for freeing the allocated data. Returns an ERR_PTR upon failure.
398 */
399static struct elf_phdr *load_elf_phdrs(struct elfhdr *elf_ex,
400 struct file *elf_file)
401{
402 struct elf_phdr *elf_phdata = NULL;
403 int retval, size, err = -1;
404
405 /*
406 * If the size of this structure has changed, then punt, since
407 * we will be doing the wrong thing.
408 */
409 if (elf_ex->e_phentsize != sizeof(struct elf_phdr))
410 goto out;
411
412 /* Sanity check the number of program headers... */
413 if (elf_ex->e_phnum < 1 ||
414 elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
415 goto out;
416
417 /* ...and their total size. */
418 size = sizeof(struct elf_phdr) * elf_ex->e_phnum;
419 if (size > ELF_MIN_ALIGN)
420 goto out;
421
422 elf_phdata = kmalloc(size, GFP_KERNEL);
423 if (!elf_phdata)
424 goto out;
425
426 /* Read in the program headers */
427 retval = kernel_read(elf_file, elf_ex->e_phoff,
428 (char *)elf_phdata, size);
429 if (retval != size) {
430 err = (retval < 0) ? retval : -EIO;
431 goto out;
432 }
433
434 /* Success! */
435 err = 0;
436out:
437 if (err) {
438 kfree(elf_phdata);
439 elf_phdata = NULL;
440 }
441 return elf_phdata;
442}
Jiri Kosinacc503c12008-01-30 13:31:07 +0100443
Paul Burton774c1052014-09-11 08:30:16 +0100444#ifndef CONFIG_ARCH_BINFMT_ELF_STATE
445
446/**
447 * struct arch_elf_state - arch-specific ELF loading state
448 *
449 * This structure is used to preserve architecture specific data during
450 * the loading of an ELF file, throughout the checking of architecture
451 * specific ELF headers & through to the point where the ELF load is
452 * known to be proceeding (ie. SET_PERSONALITY).
453 *
454 * This implementation is a dummy for architectures which require no
455 * specific state.
456 */
457struct arch_elf_state {
458};
459
460#define INIT_ARCH_ELF_STATE {}
461
462/**
463 * arch_elf_pt_proc() - check a PT_LOPROC..PT_HIPROC ELF program header
464 * @ehdr: The main ELF header
465 * @phdr: The program header to check
466 * @elf: The open ELF file
467 * @is_interp: True if the phdr is from the interpreter of the ELF being
468 * loaded, else false.
469 * @state: Architecture-specific state preserved throughout the process
470 * of loading the ELF.
471 *
472 * Inspects the program header phdr to validate its correctness and/or
473 * suitability for the system. Called once per ELF program header in the
474 * range PT_LOPROC to PT_HIPROC, for both the ELF being loaded and its
475 * interpreter.
476 *
477 * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load
478 * with that return code.
479 */
480static inline int arch_elf_pt_proc(struct elfhdr *ehdr,
481 struct elf_phdr *phdr,
482 struct file *elf, bool is_interp,
483 struct arch_elf_state *state)
484{
485 /* Dummy implementation, always proceed */
486 return 0;
487}
488
489/**
Maciej W. Rozycki54d15712015-10-26 15:47:57 +0000490 * arch_check_elf() - check an ELF executable
Paul Burton774c1052014-09-11 08:30:16 +0100491 * @ehdr: The main ELF header
492 * @has_interp: True if the ELF has an interpreter, else false.
Maciej W. Rozyckieb4bc072015-11-13 00:47:48 +0000493 * @interp_ehdr: The interpreter's ELF header
Paul Burton774c1052014-09-11 08:30:16 +0100494 * @state: Architecture-specific state preserved throughout the process
495 * of loading the ELF.
496 *
497 * Provides a final opportunity for architecture code to reject the loading
498 * of the ELF & cause an exec syscall to return an error. This is called after
499 * all program headers to be checked by arch_elf_pt_proc have been.
500 *
501 * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load
502 * with that return code.
503 */
504static inline int arch_check_elf(struct elfhdr *ehdr, bool has_interp,
Maciej W. Rozyckieb4bc072015-11-13 00:47:48 +0000505 struct elfhdr *interp_ehdr,
Paul Burton774c1052014-09-11 08:30:16 +0100506 struct arch_elf_state *state)
507{
508 /* Dummy implementation, always proceed */
509 return 0;
510}
511
512#endif /* !CONFIG_ARCH_BINFMT_ELF_STATE */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513
514/* This is much more generalized than the library routine read function,
515 so we keep this separate. Technically the library read function
516 is only provided so that we can read a.out libraries that have
517 an ELF header */
518
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700519static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
Jiri Kosinacc503c12008-01-30 13:31:07 +0100520 struct file *interpreter, unsigned long *interp_map_addr,
Paul Burtona9d9ef12014-09-11 08:30:15 +0100521 unsigned long no_base, struct elf_phdr *interp_elf_phdata)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 struct elf_phdr *eppnt;
524 unsigned long load_addr = 0;
525 int load_addr_set = 0;
526 unsigned long last_bss = 0, elf_bss = 0;
527 unsigned long error = ~0UL;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100528 unsigned long total_size;
Paul Burton6a8d3892014-09-11 08:30:14 +0100529 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530
531 /* First of all, some simple consistency checks */
532 if (interp_elf_ex->e_type != ET_EXEC &&
533 interp_elf_ex->e_type != ET_DYN)
534 goto out;
535 if (!elf_check_arch(interp_elf_ex))
536 goto out;
Al Viro72c2d532013-09-22 16:27:52 -0400537 if (!interpreter->f_op->mmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 goto out;
539
Paul Burtona9d9ef12014-09-11 08:30:15 +0100540 total_size = total_mapping_size(interp_elf_phdata,
541 interp_elf_ex->e_phnum);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100542 if (!total_size) {
543 error = -EINVAL;
Paul Burtona9d9ef12014-09-11 08:30:15 +0100544 goto out;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100545 }
546
Paul Burtona9d9ef12014-09-11 08:30:15 +0100547 eppnt = interp_elf_phdata;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700548 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
549 if (eppnt->p_type == PT_LOAD) {
550 int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
551 int elf_prot = 0;
552 unsigned long vaddr = 0;
553 unsigned long k, map_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700555 if (eppnt->p_flags & PF_R)
556 elf_prot = PROT_READ;
557 if (eppnt->p_flags & PF_W)
558 elf_prot |= PROT_WRITE;
559 if (eppnt->p_flags & PF_X)
560 elf_prot |= PROT_EXEC;
561 vaddr = eppnt->p_vaddr;
562 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
563 elf_type |= MAP_FIXED;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100564 else if (no_base && interp_elf_ex->e_type == ET_DYN)
565 load_addr = -vaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700567 map_addr = elf_map(interpreter, load_addr + vaddr,
Andrew Mortonbb1ad822008-01-30 13:31:07 +0100568 eppnt, elf_prot, elf_type, total_size);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100569 total_size = 0;
570 if (!*interp_map_addr)
571 *interp_map_addr = map_addr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700572 error = map_addr;
573 if (BAD_ADDR(map_addr))
Paul Burtona9d9ef12014-09-11 08:30:15 +0100574 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700576 if (!load_addr_set &&
577 interp_elf_ex->e_type == ET_DYN) {
578 load_addr = map_addr - ELF_PAGESTART(vaddr);
579 load_addr_set = 1;
580 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700582 /*
583 * Check to see if the section's size will overflow the
584 * allowed task size. Note that p_filesz must always be
585 * <= p_memsize so it's only necessary to check p_memsz.
586 */
587 k = load_addr + eppnt->p_vaddr;
Chuck Ebbertce510592006-07-03 00:24:14 -0700588 if (BAD_ADDR(k) ||
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700589 eppnt->p_filesz > eppnt->p_memsz ||
590 eppnt->p_memsz > TASK_SIZE ||
591 TASK_SIZE - eppnt->p_memsz < k) {
592 error = -ENOMEM;
Paul Burtona9d9ef12014-09-11 08:30:15 +0100593 goto out;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700594 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700596 /*
597 * Find the end of the file mapping for this phdr, and
598 * keep track of the largest address we see for this.
599 */
600 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
601 if (k > elf_bss)
602 elf_bss = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700604 /*
605 * Do the same thing for the memory mapping - between
606 * elf_bss and last_bss is the bss section.
607 */
Kees Cook0036d1f2016-08-02 14:04:51 -0700608 k = load_addr + eppnt->p_vaddr + eppnt->p_memsz;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700609 if (k > last_bss)
610 last_bss = k;
611 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 }
613
Kees Cook0036d1f2016-08-02 14:04:51 -0700614 /*
615 * Now fill out the bss section: first pad the last page from
616 * the file up to the page boundary, and zero it from elf_bss
617 * up to the end of the page.
618 */
619 if (padzero(elf_bss)) {
620 error = -EFAULT;
621 goto out;
622 }
623 /*
624 * Next, align both the file and mem bss up to the page size,
625 * since this is where elf_bss was just zeroed up to, and where
626 * last_bss will end after the vm_brk() below.
627 */
628 elf_bss = ELF_PAGEALIGN(elf_bss);
629 last_bss = ELF_PAGEALIGN(last_bss);
630 /* Finally, if there is still more bss to allocate, do it. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 if (last_bss > elf_bss) {
Linus Torvaldse4eb1ff2012-04-20 15:35:40 -0700632 error = vm_brk(elf_bss, last_bss - elf_bss);
Linus Torvalds5d22fc22016-05-27 15:57:31 -0700633 if (error)
Paul Burtona9d9ef12014-09-11 08:30:15 +0100634 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 }
636
Jiri Kosinacc503c12008-01-30 13:31:07 +0100637 error = load_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638out:
639 return error;
640}
641
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642/*
643 * These are the functions used to load ELF style executables and shared
644 * libraries. There is no binary dependent code anywhere else.
645 */
646
Andi Kleen913bd902006-03-25 16:29:09 +0100647#ifndef STACK_RND_MASK
James Bottomleyd1cabd62007-03-16 13:38:35 -0800648#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
Andi Kleen913bd902006-03-25 16:29:09 +0100649#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650
651static unsigned long randomize_stack_top(unsigned long stack_top)
652{
Hector Marco-Gisbert4e7c22d2015-02-14 09:33:50 -0800653 unsigned long random_variable = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654
Andi Kleenc16b63e02006-09-26 10:52:28 +0200655 if ((current->flags & PF_RANDOMIZE) &&
656 !(current->personality & ADDR_NO_RANDOMIZE)) {
Daniel Cashman5ef11c32016-02-26 15:19:37 -0800657 random_variable = get_random_long();
Hector Marco-Gisbert4e7c22d2015-02-14 09:33:50 -0800658 random_variable &= STACK_RND_MASK;
Andi Kleen913bd902006-03-25 16:29:09 +0100659 random_variable <<= PAGE_SHIFT;
660 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661#ifdef CONFIG_STACK_GROWSUP
Andi Kleen913bd902006-03-25 16:29:09 +0100662 return PAGE_ALIGN(stack_top) + random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663#else
Andi Kleen913bd902006-03-25 16:29:09 +0100664 return PAGE_ALIGN(stack_top) - random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665#endif
666}
667
Al Viro71613c32012-10-20 22:00:48 -0400668static int load_elf_binary(struct linux_binprm *bprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669{
670 struct file *interpreter = NULL; /* to shut gcc up */
671 unsigned long load_addr = 0, load_bias = 0;
672 int load_addr_set = 0;
673 char * elf_interpreter = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 unsigned long error;
Paul Burtona9d9ef12014-09-11 08:30:15 +0100675 struct elf_phdr *elf_ppnt, *elf_phdata, *interp_elf_phdata = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676 unsigned long elf_bss, elf_brk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 int retval, i;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100678 unsigned long elf_entry;
679 unsigned long interp_load_addr = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680 unsigned long start_code, end_code, start_data, end_data;
David Daney1a530a62011-03-22 16:34:48 -0700681 unsigned long reloc_func_desc __maybe_unused = 0;
David Rientjes8de61e62006-12-06 20:40:16 -0800682 int executable_stack = EXSTACK_DEFAULT;
Al Viro71613c32012-10-20 22:00:48 -0400683 struct pt_regs *regs = current_pt_regs();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 struct {
685 struct elfhdr elf_ex;
686 struct elfhdr interp_elf_ex;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 } *loc;
Paul Burton774c1052014-09-11 08:30:16 +0100688 struct arch_elf_state arch_state = INIT_ARCH_ELF_STATE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689
690 loc = kmalloc(sizeof(*loc), GFP_KERNEL);
691 if (!loc) {
692 retval = -ENOMEM;
693 goto out_ret;
694 }
695
696 /* Get the exec-header */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700697 loc->elf_ex = *((struct elfhdr *)bprm->buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698
699 retval = -ENOEXEC;
700 /* First of all, some simple consistency checks */
701 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
702 goto out;
703
704 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
705 goto out;
706 if (!elf_check_arch(&loc->elf_ex))
707 goto out;
Al Viro72c2d532013-09-22 16:27:52 -0400708 if (!bprm->file->f_op->mmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 goto out;
710
Paul Burton6a8d3892014-09-11 08:30:14 +0100711 elf_phdata = load_elf_phdrs(&loc->elf_ex, bprm->file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712 if (!elf_phdata)
713 goto out;
714
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715 elf_ppnt = elf_phdata;
716 elf_bss = 0;
717 elf_brk = 0;
718
719 start_code = ~0UL;
720 end_code = 0;
721 start_data = 0;
722 end_data = 0;
723
724 for (i = 0; i < loc->elf_ex.e_phnum; i++) {
725 if (elf_ppnt->p_type == PT_INTERP) {
726 /* This is the program interpreter used for
727 * shared libraries - for now assume that this
728 * is an a.out format binary
729 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 retval = -ENOEXEC;
731 if (elf_ppnt->p_filesz > PATH_MAX ||
732 elf_ppnt->p_filesz < 2)
Al Viroe7b9b552009-03-29 16:31:16 -0400733 goto out_free_ph;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734
735 retval = -ENOMEM;
Jesper Juhl792db3a2006-01-09 20:54:45 -0800736 elf_interpreter = kmalloc(elf_ppnt->p_filesz,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700737 GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 if (!elf_interpreter)
Al Viroe7b9b552009-03-29 16:31:16 -0400739 goto out_free_ph;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740
741 retval = kernel_read(bprm->file, elf_ppnt->p_offset,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700742 elf_interpreter,
743 elf_ppnt->p_filesz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744 if (retval != elf_ppnt->p_filesz) {
745 if (retval >= 0)
746 retval = -EIO;
747 goto out_free_interp;
748 }
749 /* make sure path is NULL terminated */
750 retval = -ENOEXEC;
751 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
752 goto out_free_interp;
753
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754 interpreter = open_exec(elf_interpreter);
755 retval = PTR_ERR(interpreter);
756 if (IS_ERR(interpreter))
757 goto out_free_interp;
Alexey Dobriyan1fb84492007-01-26 00:57:16 -0800758
759 /*
760 * If the binary is not readable then enforce
761 * mm->dumpable = 0 regardless of the interpreter's
762 * permissions.
763 */
Al Viro1b5d7832011-06-19 12:49:47 -0400764 would_dump(bprm, interpreter);
Alexey Dobriyan1fb84492007-01-26 00:57:16 -0800765
Maciej W. Rozyckib582ef52015-10-26 15:48:19 +0000766 /* Get the exec headers */
767 retval = kernel_read(interpreter, 0,
768 (void *)&loc->interp_elf_ex,
769 sizeof(loc->interp_elf_ex));
770 if (retval != sizeof(loc->interp_elf_ex)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771 if (retval >= 0)
772 retval = -EIO;
773 goto out_free_dentry;
774 }
775
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 break;
777 }
778 elf_ppnt++;
779 }
780
781 elf_ppnt = elf_phdata;
782 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
Paul Burton774c1052014-09-11 08:30:16 +0100783 switch (elf_ppnt->p_type) {
784 case PT_GNU_STACK:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 if (elf_ppnt->p_flags & PF_X)
786 executable_stack = EXSTACK_ENABLE_X;
787 else
788 executable_stack = EXSTACK_DISABLE_X;
789 break;
Paul Burton774c1052014-09-11 08:30:16 +0100790
791 case PT_LOPROC ... PT_HIPROC:
792 retval = arch_elf_pt_proc(&loc->elf_ex, elf_ppnt,
793 bprm->file, false,
794 &arch_state);
795 if (retval)
796 goto out_free_dentry;
797 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799
800 /* Some simple consistency checks for the interpreter */
801 if (elf_interpreter) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802 retval = -ELIBBAD;
Andi Kleend20894a2008-02-08 04:21:54 -0800803 /* Not an ELF interpreter */
804 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 goto out_free_dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 /* Verify the interpreter has a valid arch */
Andi Kleend20894a2008-02-08 04:21:54 -0800807 if (!elf_check_arch(&loc->interp_elf_ex))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 goto out_free_dentry;
Paul Burtona9d9ef12014-09-11 08:30:15 +0100809
810 /* Load the interpreter program headers */
811 interp_elf_phdata = load_elf_phdrs(&loc->interp_elf_ex,
812 interpreter);
813 if (!interp_elf_phdata)
814 goto out_free_dentry;
Paul Burton774c1052014-09-11 08:30:16 +0100815
816 /* Pass PT_LOPROC..PT_HIPROC headers to arch code */
817 elf_ppnt = interp_elf_phdata;
818 for (i = 0; i < loc->interp_elf_ex.e_phnum; i++, elf_ppnt++)
819 switch (elf_ppnt->p_type) {
820 case PT_LOPROC ... PT_HIPROC:
821 retval = arch_elf_pt_proc(&loc->interp_elf_ex,
822 elf_ppnt, interpreter,
823 true, &arch_state);
824 if (retval)
825 goto out_free_dentry;
826 break;
827 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 }
829
Paul Burton774c1052014-09-11 08:30:16 +0100830 /*
831 * Allow arch code to reject the ELF at this point, whilst it's
832 * still possible to return an error to the code that invoked
833 * the exec syscall.
834 */
Maciej W. Rozyckieb4bc072015-11-13 00:47:48 +0000835 retval = arch_check_elf(&loc->elf_ex,
836 !!interpreter, &loc->interp_elf_ex,
837 &arch_state);
Paul Burton774c1052014-09-11 08:30:16 +0100838 if (retval)
839 goto out_free_dentry;
840
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841 /* Flush all traces of the currently running executable */
842 retval = flush_old_exec(bprm);
843 if (retval)
844 goto out_free_dentry;
845
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
847 may depend on the personality. */
Paul Burton774c1052014-09-11 08:30:16 +0100848 SET_PERSONALITY2(loc->elf_ex, &arch_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849 if (elf_read_implies_exec(loc->elf_ex, executable_stack))
850 current->personality |= READ_IMPLIES_EXEC;
851
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700852 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853 current->flags |= PF_RANDOMIZE;
Linus Torvalds221af7f2010-01-28 22:14:42 -0800854
855 setup_new_exec(bprm);
Linus Torvalds9f834ec2016-08-22 16:41:46 -0700856 install_exec_creds(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857
858 /* Do this so that we can load the interpreter, if need be. We will
859 change some of these later */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
861 executable_stack);
Al Viro19d860a2014-05-04 20:11:36 -0400862 if (retval < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863 goto out_free_dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865 current->mm->start_stack = bprm->p;
866
André Goddard Rosaaf901ca2009-11-14 13:09:05 -0200867 /* Now we do a little grungy work by mmapping the ELF image into
Jiri Kosinacc503c12008-01-30 13:31:07 +0100868 the correct location in memory. */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700869 for(i = 0, elf_ppnt = elf_phdata;
870 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871 int elf_prot = 0, elf_flags;
872 unsigned long k, vaddr;
Michael Davidsona87938b2015-04-14 15:47:38 -0700873 unsigned long total_size = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874
875 if (elf_ppnt->p_type != PT_LOAD)
876 continue;
877
878 if (unlikely (elf_brk > elf_bss)) {
879 unsigned long nbyte;
880
881 /* There was a PT_LOAD segment with p_memsz > p_filesz
882 before this one. Map anonymous pages, if needed,
883 and clear the area. */
Mikael Petterssonf670d0e2011-01-12 17:00:02 -0800884 retval = set_brk(elf_bss + load_bias,
885 elf_brk + load_bias);
Al Viro19d860a2014-05-04 20:11:36 -0400886 if (retval)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700887 goto out_free_dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700888 nbyte = ELF_PAGEOFFSET(elf_bss);
889 if (nbyte) {
890 nbyte = ELF_MIN_ALIGN - nbyte;
891 if (nbyte > elf_brk - elf_bss)
892 nbyte = elf_brk - elf_bss;
893 if (clear_user((void __user *)elf_bss +
894 load_bias, nbyte)) {
895 /*
896 * This bss-zeroing can fail if the ELF
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700897 * file specifies odd protections. So
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898 * we don't check the return value
899 */
900 }
901 }
902 }
903
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700904 if (elf_ppnt->p_flags & PF_R)
905 elf_prot |= PROT_READ;
906 if (elf_ppnt->p_flags & PF_W)
907 elf_prot |= PROT_WRITE;
908 if (elf_ppnt->p_flags & PF_X)
909 elf_prot |= PROT_EXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700911 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912
913 vaddr = elf_ppnt->p_vaddr;
Kees Cook63c2f8f2017-07-10 15:52:37 -0700914 /*
915 * If we are loading ET_EXEC or we have already performed
916 * the ET_DYN load_addr calculations, proceed normally.
917 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
919 elf_flags |= MAP_FIXED;
920 } else if (loc->elf_ex.e_type == ET_DYN) {
Kees Cook63c2f8f2017-07-10 15:52:37 -0700921 /*
922 * This logic is run once for the first LOAD Program
923 * Header for ET_DYN binaries to calculate the
924 * randomization (load_bias) for all the LOAD
925 * Program Headers, and to calculate the entire
926 * size of the ELF mapping (total_size). (Note that
927 * load_addr_set is set to true later once the
928 * initial mapping is performed.)
929 *
930 * There are effectively two types of ET_DYN
931 * binaries: programs (i.e. PIE: ET_DYN with INTERP)
932 * and loaders (ET_DYN without INTERP, since they
933 * _are_ the ELF interpreter). The loaders must
934 * be loaded away from programs since the program
935 * may otherwise collide with the loader (especially
936 * for ET_EXEC which does not have a randomized
937 * position). For example to handle invocations of
938 * "./ld.so someprog" to test out a new version of
939 * the loader, the subsequent program that the
940 * loader loads must avoid the loader itself, so
941 * they cannot share the same load range. Sufficient
942 * room for the brk must be allocated with the
943 * loader as well, since brk must be available with
944 * the loader.
945 *
946 * Therefore, programs are loaded offset from
947 * ELF_ET_DYN_BASE and loaders are loaded into the
948 * independently randomized mmap region (0 load_bias
949 * without MAP_FIXED).
950 */
951 if (elf_interpreter) {
952 load_bias = ELF_ET_DYN_BASE;
953 if (current->flags & PF_RANDOMIZE)
954 load_bias += arch_mmap_rnd();
955 elf_flags |= MAP_FIXED;
956 } else
957 load_bias = 0;
958
959 /*
960 * Since load_bias is used for all subsequent loading
961 * calculations, we must lower it by the first vaddr
962 * so that the remaining calculations based on the
963 * ELF vaddrs will be correctly offset. The result
964 * is then page aligned.
965 */
966 load_bias = ELF_PAGESTART(load_bias - vaddr);
967
Michael Davidsona87938b2015-04-14 15:47:38 -0700968 total_size = total_mapping_size(elf_phdata,
969 loc->elf_ex.e_phnum);
970 if (!total_size) {
Andrew Morton2b1d3ae2015-05-28 15:44:24 -0700971 retval = -EINVAL;
Michael Davidsona87938b2015-04-14 15:47:38 -0700972 goto out_free_dentry;
973 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974 }
975
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700976 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
Michael Davidsona87938b2015-04-14 15:47:38 -0700977 elf_prot, elf_flags, total_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978 if (BAD_ADDR(error)) {
Alexey Kuznetsovb140f2512007-05-08 00:31:57 -0700979 retval = IS_ERR((void *)error) ?
980 PTR_ERR((void*)error) : -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 goto out_free_dentry;
982 }
983
984 if (!load_addr_set) {
985 load_addr_set = 1;
986 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
987 if (loc->elf_ex.e_type == ET_DYN) {
988 load_bias += error -
989 ELF_PAGESTART(load_bias + vaddr);
990 load_addr += load_bias;
991 reloc_func_desc = load_bias;
992 }
993 }
994 k = elf_ppnt->p_vaddr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700995 if (k < start_code)
996 start_code = k;
997 if (start_data < k)
998 start_data = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700999
1000 /*
1001 * Check to see if the section's size will overflow the
1002 * allowed task size. Note that p_filesz must always be
1003 * <= p_memsz so it is only necessary to check p_memsz.
1004 */
Chuck Ebbertce510592006-07-03 00:24:14 -07001005 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 elf_ppnt->p_memsz > TASK_SIZE ||
1007 TASK_SIZE - elf_ppnt->p_memsz < k) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001008 /* set_brk can never work. Avoid overflows. */
Alexey Kuznetsovb140f2512007-05-08 00:31:57 -07001009 retval = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001010 goto out_free_dentry;
1011 }
1012
1013 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
1014
1015 if (k > elf_bss)
1016 elf_bss = k;
1017 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
1018 end_code = k;
1019 if (end_data < k)
1020 end_data = k;
1021 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
1022 if (k > elf_brk)
1023 elf_brk = k;
1024 }
1025
1026 loc->elf_ex.e_entry += load_bias;
1027 elf_bss += load_bias;
1028 elf_brk += load_bias;
1029 start_code += load_bias;
1030 end_code += load_bias;
1031 start_data += load_bias;
1032 end_data += load_bias;
1033
1034 /* Calling set_brk effectively mmaps the pages that we need
1035 * for the bss and break sections. We must do this before
1036 * mapping in the interpreter, to make sure it doesn't wind
1037 * up getting placed where the bss needs to go.
1038 */
1039 retval = set_brk(elf_bss, elf_brk);
Al Viro19d860a2014-05-04 20:11:36 -04001040 if (retval)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001041 goto out_free_dentry;
akpm@osdl.org6de50512005-10-11 08:29:08 -07001042 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043 retval = -EFAULT; /* Nobody gets to see this, but.. */
1044 goto out_free_dentry;
1045 }
1046
1047 if (elf_interpreter) {
Alan Cox6eec4822012-10-04 17:13:42 -07001048 unsigned long interp_map_addr = 0;
Jiri Kosinacc503c12008-01-30 13:31:07 +01001049
Andi Kleend20894a2008-02-08 04:21:54 -08001050 elf_entry = load_elf_interp(&loc->interp_elf_ex,
1051 interpreter,
1052 &interp_map_addr,
Paul Burtona9d9ef12014-09-11 08:30:15 +01001053 load_bias, interp_elf_phdata);
Andi Kleend20894a2008-02-08 04:21:54 -08001054 if (!IS_ERR((void *)elf_entry)) {
1055 /*
1056 * load_elf_interp() returns relocation
1057 * adjustment
1058 */
1059 interp_load_addr = elf_entry;
1060 elf_entry += loc->interp_elf_ex.e_entry;
Jiri Kosinacc503c12008-01-30 13:31:07 +01001061 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001062 if (BAD_ADDR(elf_entry)) {
Chuck Ebbertce510592006-07-03 00:24:14 -07001063 retval = IS_ERR((void *)elf_entry) ?
1064 (int)elf_entry : -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001065 goto out_free_dentry;
1066 }
1067 reloc_func_desc = interp_load_addr;
1068
1069 allow_write_access(interpreter);
1070 fput(interpreter);
1071 kfree(elf_interpreter);
1072 } else {
1073 elf_entry = loc->elf_ex.e_entry;
Suresh Siddha5342fba2006-02-26 04:18:28 +01001074 if (BAD_ADDR(elf_entry)) {
Chuck Ebbertce510592006-07-03 00:24:14 -07001075 retval = -EINVAL;
Suresh Siddha5342fba2006-02-26 04:18:28 +01001076 goto out_free_dentry;
1077 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078 }
1079
Paul Burton774c1052014-09-11 08:30:16 +01001080 kfree(interp_elf_phdata);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081 kfree(elf_phdata);
1082
Linus Torvalds1da177e2005-04-16 15:20:36 -07001083 set_binfmt(&elf_format);
1084
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -07001085#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
Martin Schwidefskyfc5243d2008-12-25 13:38:35 +01001086 retval = arch_setup_additional_pages(bprm, !!elf_interpreter);
Al Viro19d860a2014-05-04 20:11:36 -04001087 if (retval < 0)
Roland McGrath18c8baf2005-04-28 15:17:19 -07001088 goto out;
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -07001089#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
1090
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001091 retval = create_elf_tables(bprm, &loc->elf_ex,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001092 load_addr, interp_load_addr);
Al Viro19d860a2014-05-04 20:11:36 -04001093 if (retval < 0)
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001094 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001095 /* N.B. passed_fileno might not be initialized? */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096 current->mm->end_code = end_code;
1097 current->mm->start_code = start_code;
1098 current->mm->start_data = start_data;
1099 current->mm->end_data = end_data;
1100 current->mm->start_stack = bprm->p;
1101
Jiri Kosina4471a672011-04-14 15:22:09 -07001102 if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) {
Jiri Kosinac1d171a2008-01-30 13:30:40 +01001103 current->mm->brk = current->mm->start_brk =
1104 arch_randomize_brk(current->mm);
Kees Cook204db6e2015-04-14 15:48:12 -07001105#ifdef compat_brk_randomized
Jiri Kosina4471a672011-04-14 15:22:09 -07001106 current->brk_randomized = 1;
1107#endif
1108 }
Jiri Kosinac1d171a2008-01-30 13:30:40 +01001109
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 if (current->personality & MMAP_PAGE_ZERO) {
1111 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
1112 and some applications "depend" upon this behavior.
1113 Since we do not have the power to recompile these, we
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001114 emulate the SVr4 behavior. Sigh. */
Linus Torvalds6be5ceb2012-04-20 17:13:58 -07001115 error = vm_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116 MAP_FIXED | MAP_PRIVATE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117 }
1118
1119#ifdef ELF_PLAT_INIT
1120 /*
1121 * The ABI may specify that certain registers be set up in special
1122 * ways (on i386 %edx is the address of a DT_FINI function, for
1123 * example. In addition, it may also specify (eg, PowerPC64 ELF)
1124 * that the e_entry field is the address of the function descriptor
1125 * for the startup routine, rather than the address of the startup
1126 * routine itself. This macro performs whatever initialization to
1127 * the regs structure is required as well as any relocations to the
1128 * function descriptor entries when executing dynamically links apps.
1129 */
1130 ELF_PLAT_INIT(regs, reloc_func_desc);
1131#endif
1132
1133 start_thread(regs, elf_entry, bprm->p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001134 retval = 0;
1135out:
1136 kfree(loc);
1137out_ret:
1138 return retval;
1139
1140 /* error cleanup */
1141out_free_dentry:
Paul Burtona9d9ef12014-09-11 08:30:15 +01001142 kfree(interp_elf_phdata);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143 allow_write_access(interpreter);
1144 if (interpreter)
1145 fput(interpreter);
1146out_free_interp:
Jesper Juhlf99d49a2005-11-07 01:01:34 -08001147 kfree(elf_interpreter);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148out_free_ph:
1149 kfree(elf_phdata);
1150 goto out;
1151}
1152
Josh Triplett69369a72014-04-03 14:48:27 -07001153#ifdef CONFIG_USELIB
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154/* This is really simpleminded and specialized - we are loading an
1155 a.out library that is given an ELF header. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001156static int load_elf_library(struct file *file)
1157{
1158 struct elf_phdr *elf_phdata;
1159 struct elf_phdr *eppnt;
1160 unsigned long elf_bss, bss, len;
1161 int retval, error, i, j;
1162 struct elfhdr elf_ex;
1163
1164 error = -ENOEXEC;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001165 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001166 if (retval != sizeof(elf_ex))
1167 goto out;
1168
1169 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
1170 goto out;
1171
1172 /* First of all, some simple consistency checks */
1173 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
Al Viro72c2d532013-09-22 16:27:52 -04001174 !elf_check_arch(&elf_ex) || !file->f_op->mmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001175 goto out;
1176
1177 /* Now read in all of the header information */
1178
1179 j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
1180 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1181
1182 error = -ENOMEM;
1183 elf_phdata = kmalloc(j, GFP_KERNEL);
1184 if (!elf_phdata)
1185 goto out;
1186
1187 eppnt = elf_phdata;
1188 error = -ENOEXEC;
1189 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
1190 if (retval != j)
1191 goto out_free_ph;
1192
1193 for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
1194 if ((eppnt + i)->p_type == PT_LOAD)
1195 j++;
1196 if (j != 1)
1197 goto out_free_ph;
1198
1199 while (eppnt->p_type != PT_LOAD)
1200 eppnt++;
1201
1202 /* Now use mmap to map the library into memory. */
Linus Torvalds6be5ceb2012-04-20 17:13:58 -07001203 error = vm_mmap(file,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001204 ELF_PAGESTART(eppnt->p_vaddr),
1205 (eppnt->p_filesz +
1206 ELF_PAGEOFFSET(eppnt->p_vaddr)),
1207 PROT_READ | PROT_WRITE | PROT_EXEC,
1208 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
1209 (eppnt->p_offset -
1210 ELF_PAGEOFFSET(eppnt->p_vaddr)));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001211 if (error != ELF_PAGESTART(eppnt->p_vaddr))
1212 goto out_free_ph;
1213
1214 elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
1215 if (padzero(elf_bss)) {
1216 error = -EFAULT;
1217 goto out_free_ph;
1218 }
1219
Oscar Salvadordb2858f2018-07-13 16:59:13 -07001220 len = ELF_PAGEALIGN(eppnt->p_filesz + eppnt->p_vaddr);
1221 bss = ELF_PAGEALIGN(eppnt->p_memsz + eppnt->p_vaddr);
Michal Hockoecc2bc82016-05-23 16:25:39 -07001222 if (bss > len) {
1223 error = vm_brk(len, bss - len);
Linus Torvalds5d22fc22016-05-27 15:57:31 -07001224 if (error)
Michal Hockoecc2bc82016-05-23 16:25:39 -07001225 goto out_free_ph;
1226 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001227 error = 0;
1228
1229out_free_ph:
1230 kfree(elf_phdata);
1231out:
1232 return error;
1233}
Josh Triplett69369a72014-04-03 14:48:27 -07001234#endif /* #ifdef CONFIG_USELIB */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001235
Christoph Hellwig698ba7b2009-12-15 16:47:37 -08001236#ifdef CONFIG_ELF_CORE
Linus Torvalds1da177e2005-04-16 15:20:36 -07001237/*
1238 * ELF core dumper
1239 *
1240 * Modelled on fs/exec.c:aout_core_dump()
1241 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1242 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243
1244/*
Jason Baron909af762012-03-23 15:02:51 -07001245 * The purpose of always_dump_vma() is to make sure that special kernel mappings
1246 * that are useful for post-mortem analysis are included in every core dump.
1247 * In that way we ensure that the core dump is fully interpretable later
1248 * without matching up the same kernel and hardware config to see what PC values
1249 * meant. These special mappings include - vDSO, vsyscall, and other
1250 * architecture specific mappings
1251 */
1252static bool always_dump_vma(struct vm_area_struct *vma)
1253{
1254 /* Any vsyscall mappings? */
1255 if (vma == get_gate_vma(vma->vm_mm))
1256 return true;
Andy Lutomirski78d683e2014-05-19 15:58:32 -07001257
1258 /*
1259 * Assume that all vmas with a .name op should always be dumped.
1260 * If this changes, a new vm_ops field can easily be added.
1261 */
1262 if (vma->vm_ops && vma->vm_ops->name && vma->vm_ops->name(vma))
1263 return true;
1264
Jason Baron909af762012-03-23 15:02:51 -07001265 /*
1266 * arch_vma_name() returns non-NULL for special architecture mappings,
1267 * such as vDSO sections.
1268 */
1269 if (arch_vma_name(vma))
1270 return true;
1271
1272 return false;
1273}
1274
1275/*
Roland McGrath82df3972007-10-16 23:27:02 -07001276 * Decide what to dump of a segment, part, all or none.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277 */
Roland McGrath82df3972007-10-16 23:27:02 -07001278static unsigned long vma_dump_size(struct vm_area_struct *vma,
1279 unsigned long mm_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001280{
KOSAKI Motohiroe575f112008-10-18 20:27:08 -07001281#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1282
Jason Baron909af762012-03-23 15:02:51 -07001283 /* always dump the vdso and vsyscall sections */
1284 if (always_dump_vma(vma))
Roland McGrath82df3972007-10-16 23:27:02 -07001285 goto whole;
Roland McGrathe5b97dd2007-01-26 00:56:48 -08001286
Konstantin Khlebnikov0103bd12012-10-08 16:28:59 -07001287 if (vma->vm_flags & VM_DONTDUMP)
Jason Baronaccb61f2012-03-23 15:02:51 -07001288 return 0;
1289
Ross Zwisler50378352015-10-05 16:33:36 -06001290 /* support for DAX */
1291 if (vma_is_dax(vma)) {
1292 if ((vma->vm_flags & VM_SHARED) && FILTER(DAX_SHARED))
1293 goto whole;
1294 if (!(vma->vm_flags & VM_SHARED) && FILTER(DAX_PRIVATE))
1295 goto whole;
1296 return 0;
1297 }
1298
KOSAKI Motohiroe575f112008-10-18 20:27:08 -07001299 /* Hugetlb memory check */
1300 if (vma->vm_flags & VM_HUGETLB) {
1301 if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
1302 goto whole;
1303 if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
1304 goto whole;
Naoya Horiguchi23d9e482013-04-17 15:58:28 -07001305 return 0;
KOSAKI Motohiroe575f112008-10-18 20:27:08 -07001306 }
1307
Linus Torvalds1da177e2005-04-16 15:20:36 -07001308 /* Do not dump I/O mapped devices or special mappings */
Konstantin Khlebnikov314e51b2012-10-08 16:29:02 -07001309 if (vma->vm_flags & VM_IO)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001310 return 0;
1311
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001312 /* By default, dump shared memory if mapped from an anonymous file. */
1313 if (vma->vm_flags & VM_SHARED) {
Al Viro496ad9a2013-01-23 17:07:38 -05001314 if (file_inode(vma->vm_file)->i_nlink == 0 ?
Roland McGrath82df3972007-10-16 23:27:02 -07001315 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
1316 goto whole;
1317 return 0;
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001318 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001319
Roland McGrath82df3972007-10-16 23:27:02 -07001320 /* Dump segments that have been written to. */
1321 if (vma->anon_vma && FILTER(ANON_PRIVATE))
1322 goto whole;
1323 if (vma->vm_file == NULL)
1324 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001325
Roland McGrath82df3972007-10-16 23:27:02 -07001326 if (FILTER(MAPPED_PRIVATE))
1327 goto whole;
1328
1329 /*
1330 * If this looks like the beginning of a DSO or executable mapping,
1331 * check for an ELF header. If we find one, dump the first page to
1332 * aid in determining what was mapped here.
1333 */
Roland McGrath92dc07b2009-02-06 17:34:07 -08001334 if (FILTER(ELF_HEADERS) &&
1335 vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
Roland McGrath82df3972007-10-16 23:27:02 -07001336 u32 __user *header = (u32 __user *) vma->vm_start;
1337 u32 word;
Roland McGrath92dc07b2009-02-06 17:34:07 -08001338 mm_segment_t fs = get_fs();
Roland McGrath82df3972007-10-16 23:27:02 -07001339 /*
1340 * Doing it this way gets the constant folded by GCC.
1341 */
1342 union {
1343 u32 cmp;
1344 char elfmag[SELFMAG];
1345 } magic;
1346 BUILD_BUG_ON(SELFMAG != sizeof word);
1347 magic.elfmag[EI_MAG0] = ELFMAG0;
1348 magic.elfmag[EI_MAG1] = ELFMAG1;
1349 magic.elfmag[EI_MAG2] = ELFMAG2;
1350 magic.elfmag[EI_MAG3] = ELFMAG3;
Roland McGrath92dc07b2009-02-06 17:34:07 -08001351 /*
1352 * Switch to the user "segment" for get_user(),
1353 * then put back what elf_core_dump() had in place.
1354 */
1355 set_fs(USER_DS);
1356 if (unlikely(get_user(word, header)))
1357 word = 0;
1358 set_fs(fs);
1359 if (word == magic.cmp)
Roland McGrath82df3972007-10-16 23:27:02 -07001360 return PAGE_SIZE;
1361 }
1362
1363#undef FILTER
1364
1365 return 0;
1366
1367whole:
1368 return vma->vm_end - vma->vm_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369}
1370
Linus Torvalds1da177e2005-04-16 15:20:36 -07001371/* An ELF note in memory */
1372struct memelfnote
1373{
1374 const char *name;
1375 int type;
1376 unsigned int datasz;
1377 void *data;
1378};
1379
1380static int notesize(struct memelfnote *en)
1381{
1382 int sz;
1383
1384 sz = sizeof(struct elf_note);
1385 sz += roundup(strlen(en->name) + 1, 4);
1386 sz += roundup(en->datasz, 4);
1387
1388 return sz;
1389}
1390
Al Viroecc8c772013-10-05 15:32:35 -04001391static int writenote(struct memelfnote *men, struct coredump_params *cprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001392{
1393 struct elf_note en;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394 en.n_namesz = strlen(men->name) + 1;
1395 en.n_descsz = men->datasz;
1396 en.n_type = men->type;
1397
Al Viroecc8c772013-10-05 15:32:35 -04001398 return dump_emit(cprm, &en, sizeof(en)) &&
Al Viro22a8cb82013-10-08 11:05:01 -04001399 dump_emit(cprm, men->name, en.n_namesz) && dump_align(cprm, 4) &&
1400 dump_emit(cprm, men->data, men->datasz) && dump_align(cprm, 4);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001401}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001402
Roland McGrath3aba4812008-01-30 13:31:44 +01001403static void fill_elf_header(struct elfhdr *elf, int segs,
Zhang Yanfeid3330cf2013-02-21 16:44:20 -08001404 u16 machine, u32 flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001405{
Cyrill Gorcunov6970c8e2008-04-29 01:01:18 -07001406 memset(elf, 0, sizeof(*elf));
1407
Linus Torvalds1da177e2005-04-16 15:20:36 -07001408 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1409 elf->e_ident[EI_CLASS] = ELF_CLASS;
1410 elf->e_ident[EI_DATA] = ELF_DATA;
1411 elf->e_ident[EI_VERSION] = EV_CURRENT;
1412 elf->e_ident[EI_OSABI] = ELF_OSABI;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413
1414 elf->e_type = ET_CORE;
Roland McGrath3aba4812008-01-30 13:31:44 +01001415 elf->e_machine = machine;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001416 elf->e_version = EV_CURRENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417 elf->e_phoff = sizeof(struct elfhdr);
Roland McGrath3aba4812008-01-30 13:31:44 +01001418 elf->e_flags = flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001419 elf->e_ehsize = sizeof(struct elfhdr);
1420 elf->e_phentsize = sizeof(struct elf_phdr);
1421 elf->e_phnum = segs;
Cyrill Gorcunov6970c8e2008-04-29 01:01:18 -07001422
Linus Torvalds1da177e2005-04-16 15:20:36 -07001423 return;
1424}
1425
Andrew Morton8d6b5eee2006-09-25 23:32:04 -07001426static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001427{
1428 phdr->p_type = PT_NOTE;
1429 phdr->p_offset = offset;
1430 phdr->p_vaddr = 0;
1431 phdr->p_paddr = 0;
1432 phdr->p_filesz = sz;
1433 phdr->p_memsz = 0;
1434 phdr->p_flags = 0;
1435 phdr->p_align = 0;
1436 return;
1437}
1438
1439static void fill_note(struct memelfnote *note, const char *name, int type,
1440 unsigned int sz, void *data)
1441{
1442 note->name = name;
1443 note->type = type;
1444 note->datasz = sz;
1445 note->data = data;
1446 return;
1447}
1448
1449/*
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001450 * fill up all the fields in prstatus from the given task struct, except
1451 * registers which need to be filled up separately.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001452 */
1453static void fill_prstatus(struct elf_prstatus *prstatus,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001454 struct task_struct *p, long signr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001455{
1456 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1457 prstatus->pr_sigpend = p->pending.signal.sig[0];
1458 prstatus->pr_sighold = p->blocked.sig[0];
Oleg Nesterov3b34fc52009-06-17 16:27:38 -07001459 rcu_read_lock();
1460 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1461 rcu_read_unlock();
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001462 prstatus->pr_pid = task_pid_vnr(p);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001463 prstatus->pr_pgrp = task_pgrp_vnr(p);
1464 prstatus->pr_sid = task_session_vnr(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001465 if (thread_group_leader(p)) {
Frank Mayharf06febc2008-09-12 09:54:39 -07001466 struct task_cputime cputime;
1467
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468 /*
Frank Mayharf06febc2008-09-12 09:54:39 -07001469 * This is the record for the group leader. It shows the
1470 * group-wide total, not its individual thread total.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001471 */
Frank Mayharf06febc2008-09-12 09:54:39 -07001472 thread_group_cputime(p, &cputime);
1473 cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
1474 cputime_to_timeval(cputime.stime, &prstatus->pr_stime);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001475 } else {
Frederic Weisbecker6fac4822012-11-13 14:20:55 +01001476 cputime_t utime, stime;
1477
1478 task_cputime(p, &utime, &stime);
1479 cputime_to_timeval(utime, &prstatus->pr_utime);
1480 cputime_to_timeval(stime, &prstatus->pr_stime);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001481 }
1482 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1483 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1484}
1485
1486static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1487 struct mm_struct *mm)
1488{
David Howellsc69e8d92008-11-14 10:39:19 +11001489 const struct cred *cred;
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -07001490 unsigned int i, len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001491
1492 /* first copy the parameters from user space */
1493 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1494
1495 len = mm->arg_end - mm->arg_start;
1496 if (len >= ELF_PRARGSZ)
1497 len = ELF_PRARGSZ-1;
1498 if (copy_from_user(&psinfo->pr_psargs,
1499 (const char __user *)mm->arg_start, len))
1500 return -EFAULT;
1501 for(i = 0; i < len; i++)
1502 if (psinfo->pr_psargs[i] == 0)
1503 psinfo->pr_psargs[i] = ' ';
1504 psinfo->pr_psargs[len] = 0;
1505
Oleg Nesterov3b34fc52009-06-17 16:27:38 -07001506 rcu_read_lock();
1507 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1508 rcu_read_unlock();
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001509 psinfo->pr_pid = task_pid_vnr(p);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001510 psinfo->pr_pgrp = task_pgrp_vnr(p);
1511 psinfo->pr_sid = task_session_vnr(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001512
1513 i = p->state ? ffz(~p->state) + 1 : 0;
1514 psinfo->pr_state = i;
Carsten Otte55148542006-03-25 03:08:22 -08001515 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001516 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1517 psinfo->pr_nice = task_nice(p);
1518 psinfo->pr_flag = p->flags;
David Howellsc69e8d92008-11-14 10:39:19 +11001519 rcu_read_lock();
1520 cred = __task_cred(p);
Eric W. Biedermanebc887b2012-02-07 18:36:10 -08001521 SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid));
1522 SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid));
David Howellsc69e8d92008-11-14 10:39:19 +11001523 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001524 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1525
1526 return 0;
1527}
1528
Roland McGrath3aba4812008-01-30 13:31:44 +01001529static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
1530{
1531 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
1532 int i = 0;
1533 do
1534 i += 2;
1535 while (auxv[i - 2] != AT_NULL);
1536 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
1537}
1538
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001539static void fill_siginfo_note(struct memelfnote *note, user_siginfo_t *csigdata,
Al Viroce395962013-10-13 17:23:53 -04001540 const siginfo_t *siginfo)
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001541{
1542 mm_segment_t old_fs = get_fs();
1543 set_fs(KERNEL_DS);
1544 copy_siginfo_to_user((user_siginfo_t __user *) csigdata, siginfo);
1545 set_fs(old_fs);
1546 fill_note(note, "CORE", NT_SIGINFO, sizeof(*csigdata), csigdata);
1547}
1548
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001549#define MAX_FILE_NOTE_SIZE (4*1024*1024)
1550/*
1551 * Format of NT_FILE note:
1552 *
1553 * long count -- how many files are mapped
1554 * long page_size -- units for file_ofs
1555 * array of [COUNT] elements of
1556 * long start
1557 * long end
1558 * long file_ofs
1559 * followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL...
1560 */
Dan Aloni72023652013-09-30 13:45:02 -07001561static int fill_files_note(struct memelfnote *note)
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001562{
1563 struct vm_area_struct *vma;
1564 unsigned count, size, names_ofs, remaining, n;
1565 user_long_t *data;
1566 user_long_t *start_end_ofs;
1567 char *name_base, *name_curpos;
1568
1569 /* *Estimated* file count and total data size needed */
1570 count = current->mm->map_count;
1571 size = count * 64;
1572
1573 names_ofs = (2 + 3 * count) * sizeof(data[0]);
1574 alloc:
1575 if (size >= MAX_FILE_NOTE_SIZE) /* paranoia check */
Dan Aloni72023652013-09-30 13:45:02 -07001576 return -EINVAL;
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001577 size = round_up(size, PAGE_SIZE);
1578 data = vmalloc(size);
1579 if (!data)
Dan Aloni72023652013-09-30 13:45:02 -07001580 return -ENOMEM;
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001581
1582 start_end_ofs = data + 2;
1583 name_base = name_curpos = ((char *)data) + names_ofs;
1584 remaining = size - names_ofs;
1585 count = 0;
1586 for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
1587 struct file *file;
1588 const char *filename;
1589
1590 file = vma->vm_file;
1591 if (!file)
1592 continue;
Miklos Szeredi9bf39ab2015-06-19 10:29:13 +02001593 filename = file_path(file, name_curpos, remaining);
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001594 if (IS_ERR(filename)) {
1595 if (PTR_ERR(filename) == -ENAMETOOLONG) {
1596 vfree(data);
1597 size = size * 5 / 4;
1598 goto alloc;
1599 }
1600 continue;
1601 }
1602
Miklos Szeredi9bf39ab2015-06-19 10:29:13 +02001603 /* file_path() fills at the end, move name down */
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001604 /* n = strlen(filename) + 1: */
1605 n = (name_curpos + remaining) - filename;
1606 remaining = filename - name_curpos;
1607 memmove(name_curpos, filename, n);
1608 name_curpos += n;
1609
1610 *start_end_ofs++ = vma->vm_start;
1611 *start_end_ofs++ = vma->vm_end;
1612 *start_end_ofs++ = vma->vm_pgoff;
1613 count++;
1614 }
1615
1616 /* Now we know exact count of files, can store it */
1617 data[0] = count;
1618 data[1] = PAGE_SIZE;
1619 /*
1620 * Count usually is less than current->mm->map_count,
1621 * we need to move filenames down.
1622 */
1623 n = current->mm->map_count - count;
1624 if (n != 0) {
1625 unsigned shift_bytes = n * 3 * sizeof(data[0]);
1626 memmove(name_base - shift_bytes, name_base,
1627 name_curpos - name_base);
1628 name_curpos -= shift_bytes;
1629 }
1630
1631 size = name_curpos - (char *)data;
1632 fill_note(note, "CORE", NT_FILE, size, data);
Dan Aloni72023652013-09-30 13:45:02 -07001633 return 0;
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001634}
1635
Roland McGrath4206d3a2008-01-30 13:31:45 +01001636#ifdef CORE_DUMP_USE_REGSET
1637#include <linux/regset.h>
1638
1639struct elf_thread_core_info {
1640 struct elf_thread_core_info *next;
1641 struct task_struct *task;
1642 struct elf_prstatus prstatus;
1643 struct memelfnote notes[0];
1644};
1645
1646struct elf_note_info {
1647 struct elf_thread_core_info *thread;
1648 struct memelfnote psinfo;
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001649 struct memelfnote signote;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001650 struct memelfnote auxv;
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001651 struct memelfnote files;
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001652 user_siginfo_t csigdata;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001653 size_t size;
1654 int thread_notes;
1655};
1656
Roland McGrathd31472b2008-03-04 14:28:30 -08001657/*
1658 * When a regset has a writeback hook, we call it on each thread before
1659 * dumping user memory. On register window machines, this makes sure the
1660 * user memory backing the register data is up to date before we read it.
1661 */
1662static void do_thread_regset_writeback(struct task_struct *task,
1663 const struct user_regset *regset)
1664{
1665 if (regset->writeback)
1666 regset->writeback(task, regset, 1);
1667}
1668
H. J. Lu0953f65d2012-02-14 13:34:52 -08001669#ifndef PRSTATUS_SIZE
Dmitry Safonov90954e72016-09-05 16:33:06 +03001670#define PRSTATUS_SIZE(S, R) sizeof(S)
H. J. Lu0953f65d2012-02-14 13:34:52 -08001671#endif
1672
1673#ifndef SET_PR_FPVALID
Dmitry Safonov90954e72016-09-05 16:33:06 +03001674#define SET_PR_FPVALID(S, V, R) ((S)->pr_fpvalid = (V))
H. J. Lu0953f65d2012-02-14 13:34:52 -08001675#endif
1676
Roland McGrath4206d3a2008-01-30 13:31:45 +01001677static int fill_thread_core_info(struct elf_thread_core_info *t,
1678 const struct user_regset_view *view,
1679 long signr, size_t *total)
1680{
1681 unsigned int i;
Dmitry Safonov90954e72016-09-05 16:33:06 +03001682 unsigned int regset_size = view->regsets[0].n * view->regsets[0].size;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001683
1684 /*
1685 * NT_PRSTATUS is the one special case, because the regset data
1686 * goes into the pr_reg field inside the note contents, rather
1687 * than being the whole note contents. We fill the reset in here.
1688 * We assume that regset 0 is NT_PRSTATUS.
1689 */
1690 fill_prstatus(&t->prstatus, t->task, signr);
Dmitry Safonov90954e72016-09-05 16:33:06 +03001691 (void) view->regsets[0].get(t->task, &view->regsets[0], 0, regset_size,
1692 &t->prstatus.pr_reg, NULL);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001693
1694 fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
Dmitry Safonov90954e72016-09-05 16:33:06 +03001695 PRSTATUS_SIZE(t->prstatus, regset_size), &t->prstatus);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001696 *total += notesize(&t->notes[0]);
1697
Roland McGrathd31472b2008-03-04 14:28:30 -08001698 do_thread_regset_writeback(t->task, &view->regsets[0]);
1699
Roland McGrath4206d3a2008-01-30 13:31:45 +01001700 /*
1701 * Each other regset might generate a note too. For each regset
1702 * that has no core_note_type or is inactive, we leave t->notes[i]
1703 * all zero and we'll know to skip writing it later.
1704 */
1705 for (i = 1; i < view->n; ++i) {
1706 const struct user_regset *regset = &view->regsets[i];
Roland McGrathd31472b2008-03-04 14:28:30 -08001707 do_thread_regset_writeback(t->task, regset);
H. Peter Anvinc8e25252012-03-02 10:43:48 -08001708 if (regset->core_note_type && regset->get &&
Maciej W. Rozyckie0c76342018-05-15 23:32:45 +01001709 (!regset->active || regset->active(t->task, regset) > 0)) {
Roland McGrath4206d3a2008-01-30 13:31:45 +01001710 int ret;
1711 size_t size = regset->n * regset->size;
1712 void *data = kmalloc(size, GFP_KERNEL);
1713 if (unlikely(!data))
1714 return 0;
1715 ret = regset->get(t->task, regset,
1716 0, size, data, NULL);
1717 if (unlikely(ret))
1718 kfree(data);
1719 else {
1720 if (regset->core_note_type != NT_PRFPREG)
1721 fill_note(&t->notes[i], "LINUX",
1722 regset->core_note_type,
1723 size, data);
1724 else {
Dmitry Safonov90954e72016-09-05 16:33:06 +03001725 SET_PR_FPVALID(&t->prstatus,
1726 1, regset_size);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001727 fill_note(&t->notes[i], "CORE",
1728 NT_PRFPREG, size, data);
1729 }
1730 *total += notesize(&t->notes[i]);
1731 }
1732 }
1733 }
1734
1735 return 1;
1736}
1737
1738static int fill_note_info(struct elfhdr *elf, int phdrs,
1739 struct elf_note_info *info,
Al Viroec579412013-10-13 17:57:29 -04001740 const siginfo_t *siginfo, struct pt_regs *regs)
Roland McGrath4206d3a2008-01-30 13:31:45 +01001741{
1742 struct task_struct *dump_task = current;
1743 const struct user_regset_view *view = task_user_regset_view(dump_task);
1744 struct elf_thread_core_info *t;
1745 struct elf_prpsinfo *psinfo;
Oleg Nesterov83914442008-07-25 01:47:45 -07001746 struct core_thread *ct;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001747 unsigned int i;
1748
1749 info->size = 0;
1750 info->thread = NULL;
1751
1752 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
Alan Cox6899e922012-12-17 16:02:09 -08001753 if (psinfo == NULL) {
1754 info->psinfo.data = NULL; /* So we don't free this wrongly */
Roland McGrath4206d3a2008-01-30 13:31:45 +01001755 return 0;
Alan Cox6899e922012-12-17 16:02:09 -08001756 }
Roland McGrath4206d3a2008-01-30 13:31:45 +01001757
Amerigo Wange2dbe122009-07-01 01:06:26 -04001758 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1759
Roland McGrath4206d3a2008-01-30 13:31:45 +01001760 /*
1761 * Figure out how many notes we're going to need for each thread.
1762 */
1763 info->thread_notes = 0;
1764 for (i = 0; i < view->n; ++i)
1765 if (view->regsets[i].core_note_type != 0)
1766 ++info->thread_notes;
1767
1768 /*
1769 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1770 * since it is our one special case.
1771 */
1772 if (unlikely(info->thread_notes == 0) ||
1773 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
1774 WARN_ON(1);
1775 return 0;
1776 }
1777
1778 /*
1779 * Initialize the ELF file header.
1780 */
1781 fill_elf_header(elf, phdrs,
Zhang Yanfeid3330cf2013-02-21 16:44:20 -08001782 view->e_machine, view->e_flags);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001783
1784 /*
1785 * Allocate a structure for each thread.
1786 */
Oleg Nesterov83914442008-07-25 01:47:45 -07001787 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) {
1788 t = kzalloc(offsetof(struct elf_thread_core_info,
1789 notes[info->thread_notes]),
1790 GFP_KERNEL);
1791 if (unlikely(!t))
1792 return 0;
Oleg Nesterov24d52882008-07-25 01:47:40 -07001793
Oleg Nesterov83914442008-07-25 01:47:45 -07001794 t->task = ct->task;
1795 if (ct->task == dump_task || !info->thread) {
1796 t->next = info->thread;
1797 info->thread = t;
1798 } else {
1799 /*
1800 * Make sure to keep the original task at
1801 * the head of the list.
1802 */
1803 t->next = info->thread->next;
1804 info->thread->next = t;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001805 }
Oleg Nesterov83914442008-07-25 01:47:45 -07001806 }
Roland McGrath4206d3a2008-01-30 13:31:45 +01001807
1808 /*
1809 * Now fill in each thread's information.
1810 */
1811 for (t = info->thread; t != NULL; t = t->next)
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001812 if (!fill_thread_core_info(t, view, siginfo->si_signo, &info->size))
Roland McGrath4206d3a2008-01-30 13:31:45 +01001813 return 0;
1814
1815 /*
1816 * Fill in the two process-wide notes.
1817 */
1818 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
1819 info->size += notesize(&info->psinfo);
1820
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001821 fill_siginfo_note(&info->signote, &info->csigdata, siginfo);
1822 info->size += notesize(&info->signote);
1823
Roland McGrath4206d3a2008-01-30 13:31:45 +01001824 fill_auxv_note(&info->auxv, current->mm);
1825 info->size += notesize(&info->auxv);
1826
Dan Aloni72023652013-09-30 13:45:02 -07001827 if (fill_files_note(&info->files) == 0)
1828 info->size += notesize(&info->files);
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001829
Roland McGrath4206d3a2008-01-30 13:31:45 +01001830 return 1;
1831}
1832
1833static size_t get_note_info_size(struct elf_note_info *info)
1834{
1835 return info->size;
1836}
1837
1838/*
1839 * Write all the notes for each thread. When writing the first thread, the
1840 * process-wide notes are interleaved after the first thread-specific note.
1841 */
1842static int write_note_info(struct elf_note_info *info,
Al Viroecc8c772013-10-05 15:32:35 -04001843 struct coredump_params *cprm)
Roland McGrath4206d3a2008-01-30 13:31:45 +01001844{
Fabian Frederickb219e252014-06-04 16:12:14 -07001845 bool first = true;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001846 struct elf_thread_core_info *t = info->thread;
1847
1848 do {
1849 int i;
1850
Al Viroecc8c772013-10-05 15:32:35 -04001851 if (!writenote(&t->notes[0], cprm))
Roland McGrath4206d3a2008-01-30 13:31:45 +01001852 return 0;
1853
Al Viroecc8c772013-10-05 15:32:35 -04001854 if (first && !writenote(&info->psinfo, cprm))
Roland McGrath4206d3a2008-01-30 13:31:45 +01001855 return 0;
Al Viroecc8c772013-10-05 15:32:35 -04001856 if (first && !writenote(&info->signote, cprm))
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001857 return 0;
Al Viroecc8c772013-10-05 15:32:35 -04001858 if (first && !writenote(&info->auxv, cprm))
Roland McGrath4206d3a2008-01-30 13:31:45 +01001859 return 0;
Dan Aloni72023652013-09-30 13:45:02 -07001860 if (first && info->files.data &&
Al Viroecc8c772013-10-05 15:32:35 -04001861 !writenote(&info->files, cprm))
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001862 return 0;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001863
1864 for (i = 1; i < info->thread_notes; ++i)
1865 if (t->notes[i].data &&
Al Viroecc8c772013-10-05 15:32:35 -04001866 !writenote(&t->notes[i], cprm))
Roland McGrath4206d3a2008-01-30 13:31:45 +01001867 return 0;
1868
Fabian Frederickb219e252014-06-04 16:12:14 -07001869 first = false;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001870 t = t->next;
1871 } while (t);
1872
1873 return 1;
1874}
1875
1876static void free_note_info(struct elf_note_info *info)
1877{
1878 struct elf_thread_core_info *threads = info->thread;
1879 while (threads) {
1880 unsigned int i;
1881 struct elf_thread_core_info *t = threads;
1882 threads = t->next;
1883 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
1884 for (i = 1; i < info->thread_notes; ++i)
1885 kfree(t->notes[i].data);
1886 kfree(t);
1887 }
1888 kfree(info->psinfo.data);
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001889 vfree(info->files.data);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001890}
1891
1892#else
1893
Linus Torvalds1da177e2005-04-16 15:20:36 -07001894/* Here is the structure in which status of each thread is captured. */
1895struct elf_thread_status
1896{
1897 struct list_head list;
1898 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1899 elf_fpregset_t fpu; /* NT_PRFPREG */
1900 struct task_struct *thread;
1901#ifdef ELF_CORE_COPY_XFPREGS
Mark Nelson5b20cd82007-10-16 23:25:39 -07001902 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001903#endif
1904 struct memelfnote notes[3];
1905 int num_notes;
1906};
1907
1908/*
1909 * In order to add the specific thread information for the elf file format,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001910 * we need to keep a linked list of every threads pr_status and then create
1911 * a single section for them in the final core file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001912 */
1913static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1914{
1915 int sz = 0;
1916 struct task_struct *p = t->thread;
1917 t->num_notes = 0;
1918
1919 fill_prstatus(&t->prstatus, p, signr);
1920 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1921
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001922 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1923 &(t->prstatus));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001924 t->num_notes++;
1925 sz += notesize(&t->notes[0]);
1926
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001927 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1928 &t->fpu))) {
1929 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1930 &(t->fpu));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001931 t->num_notes++;
1932 sz += notesize(&t->notes[1]);
1933 }
1934
1935#ifdef ELF_CORE_COPY_XFPREGS
1936 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
Mark Nelson5b20cd82007-10-16 23:25:39 -07001937 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1938 sizeof(t->xfpu), &t->xfpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001939 t->num_notes++;
1940 sz += notesize(&t->notes[2]);
1941 }
1942#endif
1943 return sz;
1944}
1945
Roland McGrath3aba4812008-01-30 13:31:44 +01001946struct elf_note_info {
1947 struct memelfnote *notes;
Dan Aloni72023652013-09-30 13:45:02 -07001948 struct memelfnote *notes_files;
Roland McGrath3aba4812008-01-30 13:31:44 +01001949 struct elf_prstatus *prstatus; /* NT_PRSTATUS */
1950 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */
1951 struct list_head thread_list;
1952 elf_fpregset_t *fpu;
1953#ifdef ELF_CORE_COPY_XFPREGS
1954 elf_fpxregset_t *xfpu;
1955#endif
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001956 user_siginfo_t csigdata;
Roland McGrath3aba4812008-01-30 13:31:44 +01001957 int thread_status_size;
1958 int numnote;
1959};
1960
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001961static int elf_note_info_init(struct elf_note_info *info)
Roland McGrath3aba4812008-01-30 13:31:44 +01001962{
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001963 memset(info, 0, sizeof(*info));
Roland McGrath3aba4812008-01-30 13:31:44 +01001964 INIT_LIST_HEAD(&info->thread_list);
1965
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001966 /* Allocate space for ELF notes */
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001967 info->notes = kmalloc(8 * sizeof(struct memelfnote), GFP_KERNEL);
Roland McGrath3aba4812008-01-30 13:31:44 +01001968 if (!info->notes)
1969 return 0;
1970 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
1971 if (!info->psinfo)
Denys Vlasenkof34f9d12012-09-26 11:34:50 +10001972 return 0;
Roland McGrath3aba4812008-01-30 13:31:44 +01001973 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
1974 if (!info->prstatus)
Denys Vlasenkof34f9d12012-09-26 11:34:50 +10001975 return 0;
Roland McGrath3aba4812008-01-30 13:31:44 +01001976 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
1977 if (!info->fpu)
Denys Vlasenkof34f9d12012-09-26 11:34:50 +10001978 return 0;
Roland McGrath3aba4812008-01-30 13:31:44 +01001979#ifdef ELF_CORE_COPY_XFPREGS
1980 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
1981 if (!info->xfpu)
Denys Vlasenkof34f9d12012-09-26 11:34:50 +10001982 return 0;
Roland McGrath3aba4812008-01-30 13:31:44 +01001983#endif
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001984 return 1;
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001985}
Roland McGrath3aba4812008-01-30 13:31:44 +01001986
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001987static int fill_note_info(struct elfhdr *elf, int phdrs,
1988 struct elf_note_info *info,
Al Viroec579412013-10-13 17:57:29 -04001989 const siginfo_t *siginfo, struct pt_regs *regs)
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001990{
1991 struct list_head *t;
Al Viroafabada2013-10-14 07:39:56 -04001992 struct core_thread *ct;
1993 struct elf_thread_status *ets;
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001994
1995 if (!elf_note_info_init(info))
1996 return 0;
1997
Al Viroafabada2013-10-14 07:39:56 -04001998 for (ct = current->mm->core_state->dumper.next;
1999 ct; ct = ct->next) {
2000 ets = kzalloc(sizeof(*ets), GFP_KERNEL);
2001 if (!ets)
2002 return 0;
Oleg Nesterov24d52882008-07-25 01:47:40 -07002003
Al Viroafabada2013-10-14 07:39:56 -04002004 ets->thread = ct->task;
2005 list_add(&ets->list, &info->thread_list);
2006 }
Oleg Nesterov83914442008-07-25 01:47:45 -07002007
Al Viroafabada2013-10-14 07:39:56 -04002008 list_for_each(t, &info->thread_list) {
2009 int sz;
Oleg Nesterov83914442008-07-25 01:47:45 -07002010
Al Viroafabada2013-10-14 07:39:56 -04002011 ets = list_entry(t, struct elf_thread_status, list);
2012 sz = elf_dump_thread_status(siginfo->si_signo, ets);
2013 info->thread_status_size += sz;
Roland McGrath3aba4812008-01-30 13:31:44 +01002014 }
2015 /* now collect the dump for the current */
2016 memset(info->prstatus, 0, sizeof(*info->prstatus));
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07002017 fill_prstatus(info->prstatus, current, siginfo->si_signo);
Roland McGrath3aba4812008-01-30 13:31:44 +01002018 elf_core_copy_regs(&info->prstatus->pr_reg, regs);
2019
2020 /* Set up header */
Zhang Yanfeid3330cf2013-02-21 16:44:20 -08002021 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS);
Roland McGrath3aba4812008-01-30 13:31:44 +01002022
2023 /*
2024 * Set up the notes in similar form to SVR4 core dumps made
2025 * with info from their /proc.
2026 */
2027
2028 fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
2029 sizeof(*info->prstatus), info->prstatus);
2030 fill_psinfo(info->psinfo, current->group_leader, current->mm);
2031 fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
2032 sizeof(*info->psinfo), info->psinfo);
2033
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07002034 fill_siginfo_note(info->notes + 2, &info->csigdata, siginfo);
2035 fill_auxv_note(info->notes + 3, current->mm);
Dan Aloni72023652013-09-30 13:45:02 -07002036 info->numnote = 4;
Roland McGrath3aba4812008-01-30 13:31:44 +01002037
Dan Aloni72023652013-09-30 13:45:02 -07002038 if (fill_files_note(info->notes + info->numnote) == 0) {
2039 info->notes_files = info->notes + info->numnote;
2040 info->numnote++;
2041 }
Roland McGrath3aba4812008-01-30 13:31:44 +01002042
2043 /* Try to dump the FPU. */
2044 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
2045 info->fpu);
2046 if (info->prstatus->pr_fpvalid)
2047 fill_note(info->notes + info->numnote++,
2048 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
2049#ifdef ELF_CORE_COPY_XFPREGS
2050 if (elf_core_copy_task_xfpregs(current, info->xfpu))
2051 fill_note(info->notes + info->numnote++,
2052 "LINUX", ELF_CORE_XFPREG_TYPE,
2053 sizeof(*info->xfpu), info->xfpu);
2054#endif
2055
2056 return 1;
Roland McGrath3aba4812008-01-30 13:31:44 +01002057}
2058
2059static size_t get_note_info_size(struct elf_note_info *info)
2060{
2061 int sz = 0;
2062 int i;
2063
2064 for (i = 0; i < info->numnote; i++)
2065 sz += notesize(info->notes + i);
2066
2067 sz += info->thread_status_size;
2068
2069 return sz;
2070}
2071
2072static int write_note_info(struct elf_note_info *info,
Al Viroecc8c772013-10-05 15:32:35 -04002073 struct coredump_params *cprm)
Roland McGrath3aba4812008-01-30 13:31:44 +01002074{
2075 int i;
2076 struct list_head *t;
2077
2078 for (i = 0; i < info->numnote; i++)
Al Viroecc8c772013-10-05 15:32:35 -04002079 if (!writenote(info->notes + i, cprm))
Roland McGrath3aba4812008-01-30 13:31:44 +01002080 return 0;
2081
2082 /* write out the thread status notes section */
2083 list_for_each(t, &info->thread_list) {
2084 struct elf_thread_status *tmp =
2085 list_entry(t, struct elf_thread_status, list);
2086
2087 for (i = 0; i < tmp->num_notes; i++)
Al Viroecc8c772013-10-05 15:32:35 -04002088 if (!writenote(&tmp->notes[i], cprm))
Roland McGrath3aba4812008-01-30 13:31:44 +01002089 return 0;
2090 }
2091
2092 return 1;
2093}
2094
2095static void free_note_info(struct elf_note_info *info)
2096{
2097 while (!list_empty(&info->thread_list)) {
2098 struct list_head *tmp = info->thread_list.next;
2099 list_del(tmp);
2100 kfree(list_entry(tmp, struct elf_thread_status, list));
2101 }
2102
Dan Aloni72023652013-09-30 13:45:02 -07002103 /* Free data possibly allocated by fill_files_note(): */
2104 if (info->notes_files)
2105 vfree(info->notes_files->data);
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07002106
Roland McGrath3aba4812008-01-30 13:31:44 +01002107 kfree(info->prstatus);
2108 kfree(info->psinfo);
2109 kfree(info->notes);
2110 kfree(info->fpu);
2111#ifdef ELF_CORE_COPY_XFPREGS
2112 kfree(info->xfpu);
2113#endif
2114}
2115
Roland McGrath4206d3a2008-01-30 13:31:45 +01002116#endif
2117
Roland McGrathf47aef52007-01-26 00:56:49 -08002118static struct vm_area_struct *first_vma(struct task_struct *tsk,
2119 struct vm_area_struct *gate_vma)
2120{
2121 struct vm_area_struct *ret = tsk->mm->mmap;
2122
2123 if (ret)
2124 return ret;
2125 return gate_vma;
2126}
2127/*
2128 * Helper function for iterating across a vma list. It ensures that the caller
2129 * will visit `gate_vma' prior to terminating the search.
2130 */
2131static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma,
2132 struct vm_area_struct *gate_vma)
2133{
2134 struct vm_area_struct *ret;
2135
2136 ret = this_vma->vm_next;
2137 if (ret)
2138 return ret;
2139 if (this_vma == gate_vma)
2140 return NULL;
2141 return gate_vma;
2142}
2143
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002144static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
2145 elf_addr_t e_shoff, int segs)
2146{
2147 elf->e_shoff = e_shoff;
2148 elf->e_shentsize = sizeof(*shdr4extnum);
2149 elf->e_shnum = 1;
2150 elf->e_shstrndx = SHN_UNDEF;
2151
2152 memset(shdr4extnum, 0, sizeof(*shdr4extnum));
2153
2154 shdr4extnum->sh_type = SHT_NULL;
2155 shdr4extnum->sh_size = elf->e_shnum;
2156 shdr4extnum->sh_link = elf->e_shstrndx;
2157 shdr4extnum->sh_info = segs;
2158}
2159
Linus Torvalds1da177e2005-04-16 15:20:36 -07002160/*
2161 * Actual dumper
2162 *
2163 * This is a two-pass process; first we find the offsets of the bits,
2164 * and then they are actually written out. If we run out of core limit
2165 * we just truncate.
2166 */
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08002167static int elf_core_dump(struct coredump_params *cprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002168{
Linus Torvalds1da177e2005-04-16 15:20:36 -07002169 int has_dumped = 0;
2170 mm_segment_t fs;
Jungseung Lee52f5592e2014-12-10 15:52:16 -08002171 int segs, i;
2172 size_t vma_data_size = 0;
Roland McGrathf47aef52007-01-26 00:56:49 -08002173 struct vm_area_struct *vma, *gate_vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002174 struct elfhdr *elf = NULL;
Al Virocdc3d562013-10-05 22:24:29 -04002175 loff_t offset = 0, dataoff;
Dan Aloni72023652013-09-30 13:45:02 -07002176 struct elf_note_info info = { };
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002177 struct elf_phdr *phdr4note = NULL;
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002178 struct elf_shdr *shdr4extnum = NULL;
2179 Elf_Half e_phnum;
2180 elf_addr_t e_shoff;
Jungseung Lee52f5592e2014-12-10 15:52:16 -08002181 elf_addr_t *vma_filesz = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002182
2183 /*
2184 * We no longer stop all VM operations.
2185 *
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002186 * This is because those proceses that could possibly change map_count
2187 * or the mmap / vma pages are now blocked in do_exit on current
2188 * finishing this core dump.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002189 *
2190 * Only ptrace can touch these memory addresses, but it doesn't change
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002191 * the map_count or the pages allocated. So no possibility of crashing
Linus Torvalds1da177e2005-04-16 15:20:36 -07002192 * exists while dumping the mm->vm_next areas to the core file.
2193 */
2194
2195 /* alloc memory for large data structures: too large to be on stack */
2196 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
2197 if (!elf)
WANG Cong5f719552008-05-06 12:45:35 +08002198 goto out;
KAMEZAWA Hiroyuki341c87b2009-06-30 11:41:23 -07002199 /*
2200 * The number of segs are recored into ELF header as 16bit value.
2201 * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
2202 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002203 segs = current->mm->map_count;
Daisuke HATAYAMA1fcccba2010-03-05 13:44:07 -08002204 segs += elf_core_extra_phdrs();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002205
Stephen Wilson31db58b2011-03-13 15:49:15 -04002206 gate_vma = get_gate_vma(current->mm);
Roland McGrathf47aef52007-01-26 00:56:49 -08002207 if (gate_vma != NULL)
2208 segs++;
2209
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002210 /* for notes section */
2211 segs++;
2212
2213 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
2214 * this, kernel supports extended numbering. Have a look at
2215 * include/linux/elf.h for further information. */
2216 e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
2217
Roland McGrath3aba4812008-01-30 13:31:44 +01002218 /*
2219 * Collect all the non-memory information about the process for the
2220 * notes. This also sets up the file header.
2221 */
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07002222 if (!fill_note_info(elf, e_phnum, &info, cprm->siginfo, cprm->regs))
Roland McGrath3aba4812008-01-30 13:31:44 +01002223 goto cleanup;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002224
2225 has_dumped = 1;
Oleg Nesterov079148b2013-04-30 15:28:16 -07002226
Linus Torvalds1da177e2005-04-16 15:20:36 -07002227 fs = get_fs();
2228 set_fs(KERNEL_DS);
2229
Linus Torvalds1da177e2005-04-16 15:20:36 -07002230 offset += sizeof(*elf); /* Elf header */
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002231 offset += segs * sizeof(struct elf_phdr); /* Program headers */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002232
2233 /* Write notes phdr entry */
2234 {
Roland McGrath3aba4812008-01-30 13:31:44 +01002235 size_t sz = get_note_info_size(&info);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002236
Michael Ellermane5501492007-09-19 14:38:12 +10002237 sz += elf_coredump_extra_notes_size();
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01002238
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002239 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
2240 if (!phdr4note)
Daisuke HATAYAMA088e7af2010-03-05 13:44:06 -08002241 goto end_coredump;
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002242
2243 fill_elf_note_phdr(phdr4note, sz, offset);
2244 offset += sz;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002245 }
2246
Linus Torvalds1da177e2005-04-16 15:20:36 -07002247 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
2248
Jungseung Lee52f5592e2014-12-10 15:52:16 -08002249 vma_filesz = kmalloc_array(segs - 1, sizeof(*vma_filesz), GFP_KERNEL);
2250 if (!vma_filesz)
2251 goto end_coredump;
2252
2253 for (i = 0, vma = first_vma(current, gate_vma); vma != NULL;
2254 vma = next_vma(vma, gate_vma)) {
2255 unsigned long dump_size;
2256
2257 dump_size = vma_dump_size(vma, cprm->mm_flags);
2258 vma_filesz[i++] = dump_size;
2259 vma_data_size += dump_size;
2260 }
2261
2262 offset += vma_data_size;
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002263 offset += elf_core_extra_data_size();
2264 e_shoff = offset;
2265
2266 if (e_phnum == PN_XNUM) {
2267 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
2268 if (!shdr4extnum)
2269 goto end_coredump;
2270 fill_extnum_info(elf, shdr4extnum, e_shoff, segs);
2271 }
2272
2273 offset = dataoff;
2274
Al Viroecc8c772013-10-05 15:32:35 -04002275 if (!dump_emit(cprm, elf, sizeof(*elf)))
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002276 goto end_coredump;
2277
Al Viroecc8c772013-10-05 15:32:35 -04002278 if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note)))
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002279 goto end_coredump;
2280
Linus Torvalds1da177e2005-04-16 15:20:36 -07002281 /* Write program headers for segments dump */
Jungseung Lee52f5592e2014-12-10 15:52:16 -08002282 for (i = 0, vma = first_vma(current, gate_vma); vma != NULL;
Roland McGrathf47aef52007-01-26 00:56:49 -08002283 vma = next_vma(vma, gate_vma)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002284 struct elf_phdr phdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002285
2286 phdr.p_type = PT_LOAD;
2287 phdr.p_offset = offset;
2288 phdr.p_vaddr = vma->vm_start;
2289 phdr.p_paddr = 0;
Jungseung Lee52f5592e2014-12-10 15:52:16 -08002290 phdr.p_filesz = vma_filesz[i++];
Roland McGrath82df3972007-10-16 23:27:02 -07002291 phdr.p_memsz = vma->vm_end - vma->vm_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002292 offset += phdr.p_filesz;
2293 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002294 if (vma->vm_flags & VM_WRITE)
2295 phdr.p_flags |= PF_W;
2296 if (vma->vm_flags & VM_EXEC)
2297 phdr.p_flags |= PF_X;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002298 phdr.p_align = ELF_EXEC_PAGESIZE;
2299
Al Viroecc8c772013-10-05 15:32:35 -04002300 if (!dump_emit(cprm, &phdr, sizeof(phdr)))
Daisuke HATAYAMA088e7af2010-03-05 13:44:06 -08002301 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002302 }
2303
Al Viro506f21c2013-10-05 17:22:57 -04002304 if (!elf_core_write_extra_phdrs(cprm, offset))
Daisuke HATAYAMA1fcccba2010-03-05 13:44:07 -08002305 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002306
2307 /* write out the notes section */
Al Viroecc8c772013-10-05 15:32:35 -04002308 if (!write_note_info(&info, cprm))
Roland McGrath3aba4812008-01-30 13:31:44 +01002309 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002310
Al Virocdc3d562013-10-05 22:24:29 -04002311 if (elf_coredump_extra_notes_write(cprm))
Michael Ellermane5501492007-09-19 14:38:12 +10002312 goto end_coredump;
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01002313
Andi Kleend025c9d2006-09-30 23:29:28 -07002314 /* Align to page */
Mateusz Guzik1607f092016-06-05 23:14:14 +02002315 if (!dump_skip(cprm, dataoff - cprm->pos))
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002316 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002317
Jungseung Lee52f5592e2014-12-10 15:52:16 -08002318 for (i = 0, vma = first_vma(current, gate_vma); vma != NULL;
Roland McGrathf47aef52007-01-26 00:56:49 -08002319 vma = next_vma(vma, gate_vma)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002320 unsigned long addr;
Roland McGrath82df3972007-10-16 23:27:02 -07002321 unsigned long end;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002322
Jungseung Lee52f5592e2014-12-10 15:52:16 -08002323 end = vma->vm_start + vma_filesz[i++];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002324
Roland McGrath82df3972007-10-16 23:27:02 -07002325 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002326 struct page *page;
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002327 int stop;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002328
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002329 page = get_dump_page(addr);
2330 if (page) {
2331 void *kaddr = kmap(page);
Al Viro13046ec2013-10-05 18:08:47 -04002332 stop = !dump_emit(cprm, kaddr, PAGE_SIZE);
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002333 kunmap(page);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03002334 put_page(page);
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002335 } else
Al Viro9b56d542013-10-08 09:26:08 -04002336 stop = !dump_skip(cprm, PAGE_SIZE);
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002337 if (stop)
2338 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002339 }
2340 }
Dave Kleikamp68a5dc32017-01-11 13:25:00 -06002341 dump_truncate(cprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002342
Al Viroaa3e7ea2013-10-05 17:50:15 -04002343 if (!elf_core_write_extra_data(cprm))
Daisuke HATAYAMA1fcccba2010-03-05 13:44:07 -08002344 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002345
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002346 if (e_phnum == PN_XNUM) {
Al Viro13046ec2013-10-05 18:08:47 -04002347 if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum)))
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002348 goto end_coredump;
2349 }
2350
Linus Torvalds1da177e2005-04-16 15:20:36 -07002351end_coredump:
2352 set_fs(fs);
2353
2354cleanup:
Roland McGrath3aba4812008-01-30 13:31:44 +01002355 free_note_info(&info);
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002356 kfree(shdr4extnum);
Jungseung Lee52f5592e2014-12-10 15:52:16 -08002357 kfree(vma_filesz);
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002358 kfree(phdr4note);
WANG Cong5f719552008-05-06 12:45:35 +08002359 kfree(elf);
2360out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002361 return has_dumped;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002362}
2363
Christoph Hellwig698ba7b2009-12-15 16:47:37 -08002364#endif /* CONFIG_ELF_CORE */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002365
2366static int __init init_elf_binfmt(void)
2367{
Al Viro8fc3dc52012-03-17 03:05:16 -04002368 register_binfmt(&elf_format);
2369 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002370}
2371
2372static void __exit exit_elf_binfmt(void)
2373{
2374 /* Remove the COFF and ELF loaders. */
2375 unregister_binfmt(&elf_format);
2376}
2377
2378core_initcall(init_elf_binfmt);
2379module_exit(exit_elf_binfmt);
2380MODULE_LICENSE("GPL");