blob: fbd9f60bd763310c452a08dbb34fc8bbf2515560 [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>
Alexey Dobriyan7e80d0d2007-05-08 00:28:59 -070034#include <linux/utsname.h>
Daisuke HATAYAMA088e7af2010-03-05 13:44:06 -080035#include <linux/coredump.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#include <asm/uaccess.h>
37#include <asm/param.h>
38#include <asm/page.h>
39
Denys Vlasenko2aa362c2012-10-04 17:15:36 -070040#ifndef user_long_t
41#define user_long_t long
42#endif
Denys Vlasenko49ae4d42012-10-04 17:15:35 -070043#ifndef user_siginfo_t
44#define user_siginfo_t siginfo_t
45#endif
46
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070047static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs);
48static int load_elf_library(struct file *);
Andrew Mortonbb1ad822008-01-30 13:31:07 +010049static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *,
50 int, int, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
Linus Torvalds1da177e2005-04-16 15:20:36 -070052/*
53 * If we don't support core dumping, then supply a NULL so we
54 * don't even try.
55 */
Christoph Hellwig698ba7b2009-12-15 16:47:37 -080056#ifdef CONFIG_ELF_CORE
Masami Hiramatsuf6151df2009-12-17 15:27:16 -080057static int elf_core_dump(struct coredump_params *cprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -070058#else
59#define elf_core_dump NULL
60#endif
61
62#if ELF_EXEC_PAGESIZE > PAGE_SIZE
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070063#define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
Linus Torvalds1da177e2005-04-16 15:20:36 -070064#else
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070065#define ELF_MIN_ALIGN PAGE_SIZE
Linus Torvalds1da177e2005-04-16 15:20:36 -070066#endif
67
68#ifndef ELF_CORE_EFLAGS
69#define ELF_CORE_EFLAGS 0
70#endif
71
72#define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
73#define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
74#define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
75
76static struct linux_binfmt elf_format = {
Mikael Petterssonf670d0e2011-01-12 17:00:02 -080077 .module = THIS_MODULE,
78 .load_binary = load_elf_binary,
79 .load_shlib = load_elf_library,
80 .core_dump = elf_core_dump,
81 .min_coredump = ELF_EXEC_PAGESIZE,
Linus Torvalds1da177e2005-04-16 15:20:36 -070082};
83
Andrew Mortond4e3cc32007-07-21 04:37:32 -070084#define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
Linus Torvalds1da177e2005-04-16 15:20:36 -070085
86static int set_brk(unsigned long start, unsigned long end)
87{
88 start = ELF_PAGEALIGN(start);
89 end = ELF_PAGEALIGN(end);
90 if (end > start) {
91 unsigned long addr;
Linus Torvaldse4eb1ff2012-04-20 15:35:40 -070092 addr = vm_brk(start, end - start);
Linus Torvalds1da177e2005-04-16 15:20:36 -070093 if (BAD_ADDR(addr))
94 return addr;
95 }
96 current->mm->start_brk = current->mm->brk = end;
97 return 0;
98}
99
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100/* We need to explicitly zero any fractional pages
101 after the data section (i.e. bss). This would
102 contain the junk from the file that should not
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700103 be in memory
104 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105static int padzero(unsigned long elf_bss)
106{
107 unsigned long nbyte;
108
109 nbyte = ELF_PAGEOFFSET(elf_bss);
110 if (nbyte) {
111 nbyte = ELF_MIN_ALIGN - nbyte;
112 if (clear_user((void __user *) elf_bss, nbyte))
113 return -EFAULT;
114 }
115 return 0;
116}
117
Ohad Ben-Cohen09c6dd32008-02-03 18:05:15 +0200118/* Let's use some macros to make this stack manipulation a little clearer */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119#ifdef CONFIG_STACK_GROWSUP
120#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
121#define STACK_ROUND(sp, items) \
122 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700123#define STACK_ALLOC(sp, len) ({ \
124 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
125 old_sp; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126#else
127#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
128#define STACK_ROUND(sp, items) \
129 (((unsigned long) (sp - items)) &~ 15UL)
130#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
131#endif
132
Nathan Lynch483fad12008-07-22 04:48:46 +1000133#ifndef ELF_BASE_PLATFORM
134/*
135 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
136 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
137 * will be copied to the user stack in the same manner as AT_PLATFORM.
138 */
139#define ELF_BASE_PLATFORM NULL
140#endif
141
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142static int
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700143create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
Andi Kleend20894a2008-02-08 04:21:54 -0800144 unsigned long load_addr, unsigned long interp_load_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145{
146 unsigned long p = bprm->p;
147 int argc = bprm->argc;
148 int envc = bprm->envc;
149 elf_addr_t __user *argv;
150 elf_addr_t __user *envp;
151 elf_addr_t __user *sp;
152 elf_addr_t __user *u_platform;
Nathan Lynch483fad12008-07-22 04:48:46 +1000153 elf_addr_t __user *u_base_platform;
Kees Cookf06295b2009-01-07 18:08:52 -0800154 elf_addr_t __user *u_rand_bytes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 const char *k_platform = ELF_PLATFORM;
Nathan Lynch483fad12008-07-22 04:48:46 +1000156 const char *k_base_platform = ELF_BASE_PLATFORM;
Kees Cookf06295b2009-01-07 18:08:52 -0800157 unsigned char k_rand_bytes[16];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 int items;
159 elf_addr_t *elf_info;
160 int ei_index = 0;
David Howells86a264a2008-11-14 10:39:18 +1100161 const struct cred *cred = current_cred();
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700162 struct vm_area_struct *vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
164 /*
Franck Bui-Huud68c9d62007-10-16 23:30:24 -0700165 * In some cases (e.g. Hyper-Threading), we want to avoid L1
166 * evictions by the processes running on the same package. One
167 * thing we can do is to shuffle the initial stack for them.
168 */
169
170 p = arch_align_stack(p);
171
172 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 * If this architecture has a platform capability string, copy it
174 * to userspace. In some cases (Sparc), this info is impossible
175 * for userspace to get any other way, in others (i386) it is
176 * merely difficult.
177 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 u_platform = NULL;
179 if (k_platform) {
180 size_t len = strlen(k_platform) + 1;
181
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
183 if (__copy_to_user(u_platform, k_platform, len))
184 return -EFAULT;
185 }
186
Nathan Lynch483fad12008-07-22 04:48:46 +1000187 /*
188 * If this architecture has a "base" platform capability
189 * string, copy it to userspace.
190 */
191 u_base_platform = NULL;
192 if (k_base_platform) {
193 size_t len = strlen(k_base_platform) + 1;
194
195 u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
196 if (__copy_to_user(u_base_platform, k_base_platform, len))
197 return -EFAULT;
198 }
199
Kees Cookf06295b2009-01-07 18:08:52 -0800200 /*
201 * Generate 16 random bytes for userspace PRNG seeding.
202 */
203 get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
204 u_rand_bytes = (elf_addr_t __user *)
205 STACK_ALLOC(p, sizeof(k_rand_bytes));
206 if (__copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes)))
207 return -EFAULT;
208
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 /* Create the ELF interpreter info */
Jesper Juhl785d5572006-06-23 02:05:35 -0700210 elf_info = (elf_addr_t *)current->mm->saved_auxv;
Olaf Hering4f9a58d2007-10-16 23:30:12 -0700211 /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212#define NEW_AUX_ENT(id, val) \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700213 do { \
Jesper Juhl785d5572006-06-23 02:05:35 -0700214 elf_info[ei_index++] = id; \
215 elf_info[ei_index++] = val; \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700216 } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217
218#ifdef ARCH_DLINFO
219 /*
220 * ARCH_DLINFO must come first so PPC can do its special alignment of
221 * AUXV.
Olaf Hering4f9a58d2007-10-16 23:30:12 -0700222 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
223 * ARCH_DLINFO changes
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 */
225 ARCH_DLINFO;
226#endif
227 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
228 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
229 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
230 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700231 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
233 NEW_AUX_ENT(AT_BASE, interp_load_addr);
234 NEW_AUX_ENT(AT_FLAGS, 0);
235 NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
Eric W. Biedermanebc887b2012-02-07 18:36:10 -0800236 NEW_AUX_ENT(AT_UID, from_kuid_munged(cred->user_ns, cred->uid));
237 NEW_AUX_ENT(AT_EUID, from_kuid_munged(cred->user_ns, cred->euid));
238 NEW_AUX_ENT(AT_GID, from_kgid_munged(cred->user_ns, cred->gid));
239 NEW_AUX_ENT(AT_EGID, from_kgid_munged(cred->user_ns, cred->egid));
Jesper Juhl785d5572006-06-23 02:05:35 -0700240 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
Kees Cookf06295b2009-01-07 18:08:52 -0800241 NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
John Reiser65191082008-07-21 14:21:32 -0700242 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 if (k_platform) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700244 NEW_AUX_ENT(AT_PLATFORM,
Jesper Juhl785d5572006-06-23 02:05:35 -0700245 (elf_addr_t)(unsigned long)u_platform);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246 }
Nathan Lynch483fad12008-07-22 04:48:46 +1000247 if (k_base_platform) {
248 NEW_AUX_ENT(AT_BASE_PLATFORM,
249 (elf_addr_t)(unsigned long)u_base_platform);
250 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
Jesper Juhl785d5572006-06-23 02:05:35 -0700252 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 }
254#undef NEW_AUX_ENT
255 /* AT_NULL is zero; clear the rest too */
256 memset(&elf_info[ei_index], 0,
257 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
258
259 /* And advance past the AT_NULL entry. */
260 ei_index += 2;
261
262 sp = STACK_ADD(p, ei_index);
263
Andi Kleend20894a2008-02-08 04:21:54 -0800264 items = (argc + 1) + (envc + 1) + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 bprm->p = STACK_ROUND(sp, items);
266
267 /* Point sp at the lowest address on the stack */
268#ifdef CONFIG_STACK_GROWSUP
269 sp = (elf_addr_t __user *)bprm->p - items - ei_index;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700270 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271#else
272 sp = (elf_addr_t __user *)bprm->p;
273#endif
274
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700275
276 /*
277 * Grow the stack manually; some architectures have a limit on how
278 * far ahead a user-space access may be in order to grow the stack.
279 */
280 vma = find_extend_vma(current->mm, bprm->p);
281 if (!vma)
282 return -EFAULT;
283
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284 /* Now, let's put argc (and argv, envp if appropriate) on the stack */
285 if (__put_user(argc, sp++))
286 return -EFAULT;
Andi Kleend20894a2008-02-08 04:21:54 -0800287 argv = sp;
288 envp = argv + argc + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289
290 /* Populate argv and envp */
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -0700291 p = current->mm->arg_end = current->mm->arg_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 while (argc-- > 0) {
293 size_t len;
Heiko Carstens841d5fb2006-12-06 20:36:35 -0800294 if (__put_user((elf_addr_t)p, argv++))
295 return -EFAULT;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700296 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
297 if (!len || len > MAX_ARG_STRLEN)
WANG Cong23c49712008-05-08 21:52:33 +0800298 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 p += len;
300 }
301 if (__put_user(0, argv))
302 return -EFAULT;
303 current->mm->arg_end = current->mm->env_start = p;
304 while (envc-- > 0) {
305 size_t len;
Heiko Carstens841d5fb2006-12-06 20:36:35 -0800306 if (__put_user((elf_addr_t)p, envp++))
307 return -EFAULT;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700308 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
309 if (!len || len > MAX_ARG_STRLEN)
WANG Cong23c49712008-05-08 21:52:33 +0800310 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 p += len;
312 }
313 if (__put_user(0, envp))
314 return -EFAULT;
315 current->mm->env_end = p;
316
317 /* Put the elf_info on the stack in the right place. */
318 sp = (elf_addr_t __user *)envp + 1;
319 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
320 return -EFAULT;
321 return 0;
322}
323
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324static unsigned long elf_map(struct file *filep, unsigned long addr,
Jiri Kosinacc503c12008-01-30 13:31:07 +0100325 struct elf_phdr *eppnt, int prot, int type,
326 unsigned long total_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327{
328 unsigned long map_addr;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100329 unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
330 unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
331 addr = ELF_PAGESTART(addr);
332 size = ELF_PAGEALIGN(size);
Jan Kratochvil60bfba72007-07-15 23:40:06 -0700333
Andrew Mortond4e3cc32007-07-21 04:37:32 -0700334 /* mmap() will return -EINVAL if given a zero size, but a
335 * segment with zero filesize is perfectly valid */
Jiri Kosinacc503c12008-01-30 13:31:07 +0100336 if (!size)
337 return addr;
338
Jiri Kosinacc503c12008-01-30 13:31:07 +0100339 /*
340 * total_size is the size of the ELF (interpreter) image.
341 * The _first_ mmap needs to know the full size, otherwise
342 * randomization might put this image into an overlapping
343 * position with the ELF binary image. (since size < total_size)
344 * So we first map the 'big' image - and unmap the remainder at
345 * the end. (which unmap is needed for ELF images with holes.)
346 */
347 if (total_size) {
348 total_size = ELF_PAGEALIGN(total_size);
Al Viro5a5e4c22012-05-30 01:49:38 -0400349 map_addr = vm_mmap(filep, addr, total_size, prot, type, off);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100350 if (!BAD_ADDR(map_addr))
Al Viro5a5e4c22012-05-30 01:49:38 -0400351 vm_munmap(map_addr+size, total_size-size);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100352 } else
Al Viro5a5e4c22012-05-30 01:49:38 -0400353 map_addr = vm_mmap(filep, addr, size, prot, type, off);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100354
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 return(map_addr);
356}
357
Jiri Kosinacc503c12008-01-30 13:31:07 +0100358static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr)
359{
360 int i, first_idx = -1, last_idx = -1;
361
362 for (i = 0; i < nr; i++) {
363 if (cmds[i].p_type == PT_LOAD) {
364 last_idx = i;
365 if (first_idx == -1)
366 first_idx = i;
367 }
368 }
369 if (first_idx == -1)
370 return 0;
371
372 return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz -
373 ELF_PAGESTART(cmds[first_idx].p_vaddr);
374}
375
376
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377/* This is much more generalized than the library routine read function,
378 so we keep this separate. Technically the library read function
379 is only provided so that we can read a.out libraries that have
380 an ELF header */
381
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700382static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
Jiri Kosinacc503c12008-01-30 13:31:07 +0100383 struct file *interpreter, unsigned long *interp_map_addr,
384 unsigned long no_base)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385{
386 struct elf_phdr *elf_phdata;
387 struct elf_phdr *eppnt;
388 unsigned long load_addr = 0;
389 int load_addr_set = 0;
390 unsigned long last_bss = 0, elf_bss = 0;
391 unsigned long error = ~0UL;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100392 unsigned long total_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 int retval, i, size;
394
395 /* First of all, some simple consistency checks */
396 if (interp_elf_ex->e_type != ET_EXEC &&
397 interp_elf_ex->e_type != ET_DYN)
398 goto out;
399 if (!elf_check_arch(interp_elf_ex))
400 goto out;
401 if (!interpreter->f_op || !interpreter->f_op->mmap)
402 goto out;
403
404 /*
405 * If the size of this structure has changed, then punt, since
406 * we will be doing the wrong thing.
407 */
408 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
409 goto out;
410 if (interp_elf_ex->e_phnum < 1 ||
411 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
412 goto out;
413
414 /* Now read in all of the header information */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
416 if (size > ELF_MIN_ALIGN)
417 goto out;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700418 elf_phdata = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 if (!elf_phdata)
420 goto out;
421
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700422 retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
Mikael Petterssonf670d0e2011-01-12 17:00:02 -0800423 (char *)elf_phdata, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 error = -EIO;
425 if (retval != size) {
426 if (retval < 0)
427 error = retval;
428 goto out_close;
429 }
430
Jiri Kosinacc503c12008-01-30 13:31:07 +0100431 total_size = total_mapping_size(elf_phdata, interp_elf_ex->e_phnum);
432 if (!total_size) {
433 error = -EINVAL;
434 goto out_close;
435 }
436
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437 eppnt = elf_phdata;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700438 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
439 if (eppnt->p_type == PT_LOAD) {
440 int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
441 int elf_prot = 0;
442 unsigned long vaddr = 0;
443 unsigned long k, map_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700445 if (eppnt->p_flags & PF_R)
446 elf_prot = PROT_READ;
447 if (eppnt->p_flags & PF_W)
448 elf_prot |= PROT_WRITE;
449 if (eppnt->p_flags & PF_X)
450 elf_prot |= PROT_EXEC;
451 vaddr = eppnt->p_vaddr;
452 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
453 elf_type |= MAP_FIXED;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100454 else if (no_base && interp_elf_ex->e_type == ET_DYN)
455 load_addr = -vaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700457 map_addr = elf_map(interpreter, load_addr + vaddr,
Andrew Mortonbb1ad822008-01-30 13:31:07 +0100458 eppnt, elf_prot, elf_type, total_size);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100459 total_size = 0;
460 if (!*interp_map_addr)
461 *interp_map_addr = map_addr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700462 error = map_addr;
463 if (BAD_ADDR(map_addr))
464 goto out_close;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700466 if (!load_addr_set &&
467 interp_elf_ex->e_type == ET_DYN) {
468 load_addr = map_addr - ELF_PAGESTART(vaddr);
469 load_addr_set = 1;
470 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700472 /*
473 * Check to see if the section's size will overflow the
474 * allowed task size. Note that p_filesz must always be
475 * <= p_memsize so it's only necessary to check p_memsz.
476 */
477 k = load_addr + eppnt->p_vaddr;
Chuck Ebbertce510592006-07-03 00:24:14 -0700478 if (BAD_ADDR(k) ||
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700479 eppnt->p_filesz > eppnt->p_memsz ||
480 eppnt->p_memsz > TASK_SIZE ||
481 TASK_SIZE - eppnt->p_memsz < k) {
482 error = -ENOMEM;
483 goto out_close;
484 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700486 /*
487 * Find the end of the file mapping for this phdr, and
488 * keep track of the largest address we see for this.
489 */
490 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
491 if (k > elf_bss)
492 elf_bss = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700494 /*
495 * Do the same thing for the memory mapping - between
496 * elf_bss and last_bss is the bss section.
497 */
498 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
499 if (k > last_bss)
500 last_bss = k;
501 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502 }
503
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 if (last_bss > elf_bss) {
Roland McGrath752015d2009-09-08 19:49:40 -0700505 /*
506 * Now fill out the bss section. First pad the last page up
507 * to the page boundary, and then perform a mmap to make sure
508 * that there are zero-mapped pages up to and including the
509 * last bss page.
510 */
511 if (padzero(elf_bss)) {
512 error = -EFAULT;
513 goto out_close;
514 }
515
516 /* What we have mapped so far */
517 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
518
519 /* Map the last of the bss segment */
Linus Torvaldse4eb1ff2012-04-20 15:35:40 -0700520 error = vm_brk(elf_bss, last_bss - elf_bss);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521 if (BAD_ADDR(error))
522 goto out_close;
523 }
524
Jiri Kosinacc503c12008-01-30 13:31:07 +0100525 error = load_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526
527out_close:
528 kfree(elf_phdata);
529out:
530 return error;
531}
532
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533/*
534 * These are the functions used to load ELF style executables and shared
535 * libraries. There is no binary dependent code anywhere else.
536 */
537
538#define INTERPRETER_NONE 0
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539#define INTERPRETER_ELF 2
540
Andi Kleen913bd902006-03-25 16:29:09 +0100541#ifndef STACK_RND_MASK
James Bottomleyd1cabd62007-03-16 13:38:35 -0800542#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
Andi Kleen913bd902006-03-25 16:29:09 +0100543#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544
545static unsigned long randomize_stack_top(unsigned long stack_top)
546{
547 unsigned int random_variable = 0;
548
Andi Kleenc16b63e02006-09-26 10:52:28 +0200549 if ((current->flags & PF_RANDOMIZE) &&
550 !(current->personality & ADDR_NO_RANDOMIZE)) {
Andi Kleen913bd902006-03-25 16:29:09 +0100551 random_variable = get_random_int() & STACK_RND_MASK;
552 random_variable <<= PAGE_SHIFT;
553 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554#ifdef CONFIG_STACK_GROWSUP
Andi Kleen913bd902006-03-25 16:29:09 +0100555 return PAGE_ALIGN(stack_top) + random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556#else
Andi Kleen913bd902006-03-25 16:29:09 +0100557 return PAGE_ALIGN(stack_top) - random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558#endif
559}
560
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700561static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562{
563 struct file *interpreter = NULL; /* to shut gcc up */
564 unsigned long load_addr = 0, load_bias = 0;
565 int load_addr_set = 0;
566 char * elf_interpreter = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 unsigned long error;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700568 struct elf_phdr *elf_ppnt, *elf_phdata;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569 unsigned long elf_bss, elf_brk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 int retval, i;
571 unsigned int size;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100572 unsigned long elf_entry;
573 unsigned long interp_load_addr = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 unsigned long start_code, end_code, start_data, end_data;
David Daney1a530a62011-03-22 16:34:48 -0700575 unsigned long reloc_func_desc __maybe_unused = 0;
David Rientjes8de61e62006-12-06 20:40:16 -0800576 int executable_stack = EXSTACK_DEFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 unsigned long def_flags = 0;
578 struct {
579 struct elfhdr elf_ex;
580 struct elfhdr interp_elf_ex;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 } *loc;
582
583 loc = kmalloc(sizeof(*loc), GFP_KERNEL);
584 if (!loc) {
585 retval = -ENOMEM;
586 goto out_ret;
587 }
588
589 /* Get the exec-header */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700590 loc->elf_ex = *((struct elfhdr *)bprm->buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591
592 retval = -ENOEXEC;
593 /* First of all, some simple consistency checks */
594 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
595 goto out;
596
597 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
598 goto out;
599 if (!elf_check_arch(&loc->elf_ex))
600 goto out;
Mikael Petterssonf670d0e2011-01-12 17:00:02 -0800601 if (!bprm->file->f_op || !bprm->file->f_op->mmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 goto out;
603
604 /* Now read in all of the header information */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr))
606 goto out;
607 if (loc->elf_ex.e_phnum < 1 ||
608 loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr))
609 goto out;
610 size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr);
611 retval = -ENOMEM;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700612 elf_phdata = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 if (!elf_phdata)
614 goto out;
615
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700616 retval = kernel_read(bprm->file, loc->elf_ex.e_phoff,
617 (char *)elf_phdata, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 if (retval != size) {
619 if (retval >= 0)
620 retval = -EIO;
621 goto out_free_ph;
622 }
623
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624 elf_ppnt = elf_phdata;
625 elf_bss = 0;
626 elf_brk = 0;
627
628 start_code = ~0UL;
629 end_code = 0;
630 start_data = 0;
631 end_data = 0;
632
633 for (i = 0; i < loc->elf_ex.e_phnum; i++) {
634 if (elf_ppnt->p_type == PT_INTERP) {
635 /* This is the program interpreter used for
636 * shared libraries - for now assume that this
637 * is an a.out format binary
638 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 retval = -ENOEXEC;
640 if (elf_ppnt->p_filesz > PATH_MAX ||
641 elf_ppnt->p_filesz < 2)
Al Viroe7b9b552009-03-29 16:31:16 -0400642 goto out_free_ph;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643
644 retval = -ENOMEM;
Jesper Juhl792db3a2006-01-09 20:54:45 -0800645 elf_interpreter = kmalloc(elf_ppnt->p_filesz,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700646 GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 if (!elf_interpreter)
Al Viroe7b9b552009-03-29 16:31:16 -0400648 goto out_free_ph;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649
650 retval = kernel_read(bprm->file, elf_ppnt->p_offset,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700651 elf_interpreter,
652 elf_ppnt->p_filesz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653 if (retval != elf_ppnt->p_filesz) {
654 if (retval >= 0)
655 retval = -EIO;
656 goto out_free_interp;
657 }
658 /* make sure path is NULL terminated */
659 retval = -ENOEXEC;
660 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
661 goto out_free_interp;
662
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 interpreter = open_exec(elf_interpreter);
664 retval = PTR_ERR(interpreter);
665 if (IS_ERR(interpreter))
666 goto out_free_interp;
Alexey Dobriyan1fb84492007-01-26 00:57:16 -0800667
668 /*
669 * If the binary is not readable then enforce
670 * mm->dumpable = 0 regardless of the interpreter's
671 * permissions.
672 */
Al Viro1b5d7832011-06-19 12:49:47 -0400673 would_dump(bprm, interpreter);
Alexey Dobriyan1fb84492007-01-26 00:57:16 -0800674
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700675 retval = kernel_read(interpreter, 0, bprm->buf,
676 BINPRM_BUF_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 if (retval != BINPRM_BUF_SIZE) {
678 if (retval >= 0)
679 retval = -EIO;
680 goto out_free_dentry;
681 }
682
683 /* Get the exec headers */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700684 loc->interp_elf_ex = *((struct elfhdr *)bprm->buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685 break;
686 }
687 elf_ppnt++;
688 }
689
690 elf_ppnt = elf_phdata;
691 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
692 if (elf_ppnt->p_type == PT_GNU_STACK) {
693 if (elf_ppnt->p_flags & PF_X)
694 executable_stack = EXSTACK_ENABLE_X;
695 else
696 executable_stack = EXSTACK_DISABLE_X;
697 break;
698 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699
700 /* Some simple consistency checks for the interpreter */
701 if (elf_interpreter) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702 retval = -ELIBBAD;
Andi Kleend20894a2008-02-08 04:21:54 -0800703 /* Not an ELF interpreter */
704 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705 goto out_free_dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706 /* Verify the interpreter has a valid arch */
Andi Kleend20894a2008-02-08 04:21:54 -0800707 if (!elf_check_arch(&loc->interp_elf_ex))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708 goto out_free_dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 }
710
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 /* Flush all traces of the currently running executable */
712 retval = flush_old_exec(bprm);
713 if (retval)
714 goto out_free_dentry;
715
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716 /* OK, This is the point of no return */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717 current->mm->def_flags = def_flags;
718
719 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
720 may depend on the personality. */
Martin Schwidefsky0b592682008-10-16 15:39:57 +0200721 SET_PERSONALITY(loc->elf_ex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722 if (elf_read_implies_exec(loc->elf_ex, executable_stack))
723 current->personality |= READ_IMPLIES_EXEC;
724
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700725 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 current->flags |= PF_RANDOMIZE;
Linus Torvalds221af7f2010-01-28 22:14:42 -0800727
728 setup_new_exec(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729
730 /* Do this so that we can load the interpreter, if need be. We will
731 change some of these later */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732 current->mm->free_area_cache = current->mm->mmap_base;
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700733 current->mm->cached_hole_size = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
735 executable_stack);
736 if (retval < 0) {
737 send_sig(SIGKILL, current, 0);
738 goto out_free_dentry;
739 }
740
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 current->mm->start_stack = bprm->p;
742
André Goddard Rosaaf901ca2009-11-14 13:09:05 -0200743 /* Now we do a little grungy work by mmapping the ELF image into
Jiri Kosinacc503c12008-01-30 13:31:07 +0100744 the correct location in memory. */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700745 for(i = 0, elf_ppnt = elf_phdata;
746 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 int elf_prot = 0, elf_flags;
748 unsigned long k, vaddr;
749
750 if (elf_ppnt->p_type != PT_LOAD)
751 continue;
752
753 if (unlikely (elf_brk > elf_bss)) {
754 unsigned long nbyte;
755
756 /* There was a PT_LOAD segment with p_memsz > p_filesz
757 before this one. Map anonymous pages, if needed,
758 and clear the area. */
Mikael Petterssonf670d0e2011-01-12 17:00:02 -0800759 retval = set_brk(elf_bss + load_bias,
760 elf_brk + load_bias);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 if (retval) {
762 send_sig(SIGKILL, current, 0);
763 goto out_free_dentry;
764 }
765 nbyte = ELF_PAGEOFFSET(elf_bss);
766 if (nbyte) {
767 nbyte = ELF_MIN_ALIGN - nbyte;
768 if (nbyte > elf_brk - elf_bss)
769 nbyte = elf_brk - elf_bss;
770 if (clear_user((void __user *)elf_bss +
771 load_bias, nbyte)) {
772 /*
773 * This bss-zeroing can fail if the ELF
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700774 * file specifies odd protections. So
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775 * we don't check the return value
776 */
777 }
778 }
779 }
780
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700781 if (elf_ppnt->p_flags & PF_R)
782 elf_prot |= PROT_READ;
783 if (elf_ppnt->p_flags & PF_W)
784 elf_prot |= PROT_WRITE;
785 if (elf_ppnt->p_flags & PF_X)
786 elf_prot |= PROT_EXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700788 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789
790 vaddr = elf_ppnt->p_vaddr;
791 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
792 elf_flags |= MAP_FIXED;
793 } else if (loc->elf_ex.e_type == ET_DYN) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700794 /* Try and get dynamic programs out of the way of the
795 * default mmap base, as well as whatever program they
796 * might try to exec. This is because the brk will
797 * follow the loader, and is not movable. */
David Daneye39f5602012-01-10 15:10:21 -0800798#ifdef CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE
Jiri Kosinaa3defbe2011-11-02 13:37:41 -0700799 /* Memory randomization might have been switched off
800 * in runtime via sysctl.
801 * If that is the case, retain the original non-zero
802 * load_bias value in order to establish proper
803 * non-randomized mappings.
804 */
805 if (current->flags & PF_RANDOMIZE)
806 load_bias = 0;
807 else
808 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100809#else
Linus Torvalds90cb28e2007-01-06 13:28:21 -0800810 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100811#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 }
813
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700814 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
Andrew Mortonbb1ad822008-01-30 13:31:07 +0100815 elf_prot, elf_flags, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 if (BAD_ADDR(error)) {
817 send_sig(SIGKILL, current, 0);
Alexey Kuznetsovb140f2512007-05-08 00:31:57 -0700818 retval = IS_ERR((void *)error) ?
819 PTR_ERR((void*)error) : -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820 goto out_free_dentry;
821 }
822
823 if (!load_addr_set) {
824 load_addr_set = 1;
825 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
826 if (loc->elf_ex.e_type == ET_DYN) {
827 load_bias += error -
828 ELF_PAGESTART(load_bias + vaddr);
829 load_addr += load_bias;
830 reloc_func_desc = load_bias;
831 }
832 }
833 k = elf_ppnt->p_vaddr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700834 if (k < start_code)
835 start_code = k;
836 if (start_data < k)
837 start_data = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838
839 /*
840 * Check to see if the section's size will overflow the
841 * allowed task size. Note that p_filesz must always be
842 * <= p_memsz so it is only necessary to check p_memsz.
843 */
Chuck Ebbertce510592006-07-03 00:24:14 -0700844 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845 elf_ppnt->p_memsz > TASK_SIZE ||
846 TASK_SIZE - elf_ppnt->p_memsz < k) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700847 /* set_brk can never work. Avoid overflows. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 send_sig(SIGKILL, current, 0);
Alexey Kuznetsovb140f2512007-05-08 00:31:57 -0700849 retval = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850 goto out_free_dentry;
851 }
852
853 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
854
855 if (k > elf_bss)
856 elf_bss = k;
857 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
858 end_code = k;
859 if (end_data < k)
860 end_data = k;
861 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
862 if (k > elf_brk)
863 elf_brk = k;
864 }
865
866 loc->elf_ex.e_entry += load_bias;
867 elf_bss += load_bias;
868 elf_brk += load_bias;
869 start_code += load_bias;
870 end_code += load_bias;
871 start_data += load_bias;
872 end_data += load_bias;
873
874 /* Calling set_brk effectively mmaps the pages that we need
875 * for the bss and break sections. We must do this before
876 * mapping in the interpreter, to make sure it doesn't wind
877 * up getting placed where the bss needs to go.
878 */
879 retval = set_brk(elf_bss, elf_brk);
880 if (retval) {
881 send_sig(SIGKILL, current, 0);
882 goto out_free_dentry;
883 }
akpm@osdl.org6de50512005-10-11 08:29:08 -0700884 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885 send_sig(SIGSEGV, current, 0);
886 retval = -EFAULT; /* Nobody gets to see this, but.. */
887 goto out_free_dentry;
888 }
889
890 if (elf_interpreter) {
Alan Cox6eec4822012-10-04 17:13:42 -0700891 unsigned long interp_map_addr = 0;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100892
Andi Kleend20894a2008-02-08 04:21:54 -0800893 elf_entry = load_elf_interp(&loc->interp_elf_ex,
894 interpreter,
895 &interp_map_addr,
896 load_bias);
897 if (!IS_ERR((void *)elf_entry)) {
898 /*
899 * load_elf_interp() returns relocation
900 * adjustment
901 */
902 interp_load_addr = elf_entry;
903 elf_entry += loc->interp_elf_ex.e_entry;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100904 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905 if (BAD_ADDR(elf_entry)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906 force_sig(SIGSEGV, current);
Chuck Ebbertce510592006-07-03 00:24:14 -0700907 retval = IS_ERR((void *)elf_entry) ?
908 (int)elf_entry : -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700909 goto out_free_dentry;
910 }
911 reloc_func_desc = interp_load_addr;
912
913 allow_write_access(interpreter);
914 fput(interpreter);
915 kfree(elf_interpreter);
916 } else {
917 elf_entry = loc->elf_ex.e_entry;
Suresh Siddha5342fba2006-02-26 04:18:28 +0100918 if (BAD_ADDR(elf_entry)) {
Chuck Ebbertce510592006-07-03 00:24:14 -0700919 force_sig(SIGSEGV, current);
920 retval = -EINVAL;
Suresh Siddha5342fba2006-02-26 04:18:28 +0100921 goto out_free_dentry;
922 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700923 }
924
925 kfree(elf_phdata);
926
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927 set_binfmt(&elf_format);
928
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -0700929#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
Martin Schwidefskyfc5243d2008-12-25 13:38:35 +0100930 retval = arch_setup_additional_pages(bprm, !!elf_interpreter);
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -0700931 if (retval < 0) {
932 send_sig(SIGKILL, current, 0);
Roland McGrath18c8baf2005-04-28 15:17:19 -0700933 goto out;
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -0700934 }
935#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
936
David Howellsa6f76f22008-11-14 10:39:24 +1100937 install_exec_creds(bprm);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700938 retval = create_elf_tables(bprm, &loc->elf_ex,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700939 load_addr, interp_load_addr);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700940 if (retval < 0) {
941 send_sig(SIGKILL, current, 0);
942 goto out;
943 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944 /* N.B. passed_fileno might not be initialized? */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 current->mm->end_code = end_code;
946 current->mm->start_code = start_code;
947 current->mm->start_data = start_data;
948 current->mm->end_data = end_data;
949 current->mm->start_stack = bprm->p;
950
Jiri Kosinac1d171a2008-01-30 13:30:40 +0100951#ifdef arch_randomize_brk
Jiri Kosina4471a672011-04-14 15:22:09 -0700952 if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) {
Jiri Kosinac1d171a2008-01-30 13:30:40 +0100953 current->mm->brk = current->mm->start_brk =
954 arch_randomize_brk(current->mm);
Jiri Kosina4471a672011-04-14 15:22:09 -0700955#ifdef CONFIG_COMPAT_BRK
956 current->brk_randomized = 1;
957#endif
958 }
Jiri Kosinac1d171a2008-01-30 13:30:40 +0100959#endif
960
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961 if (current->personality & MMAP_PAGE_ZERO) {
962 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
963 and some applications "depend" upon this behavior.
964 Since we do not have the power to recompile these, we
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700965 emulate the SVr4 behavior. Sigh. */
Linus Torvalds6be5ceb2012-04-20 17:13:58 -0700966 error = vm_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967 MAP_FIXED | MAP_PRIVATE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968 }
969
970#ifdef ELF_PLAT_INIT
971 /*
972 * The ABI may specify that certain registers be set up in special
973 * ways (on i386 %edx is the address of a DT_FINI function, for
974 * example. In addition, it may also specify (eg, PowerPC64 ELF)
975 * that the e_entry field is the address of the function descriptor
976 * for the startup routine, rather than the address of the startup
977 * routine itself. This macro performs whatever initialization to
978 * the regs structure is required as well as any relocations to the
979 * function descriptor entries when executing dynamically links apps.
980 */
981 ELF_PLAT_INIT(regs, reloc_func_desc);
982#endif
983
984 start_thread(regs, elf_entry, bprm->p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985 retval = 0;
986out:
987 kfree(loc);
988out_ret:
989 return retval;
990
991 /* error cleanup */
992out_free_dentry:
993 allow_write_access(interpreter);
994 if (interpreter)
995 fput(interpreter);
996out_free_interp:
Jesper Juhlf99d49a2005-11-07 01:01:34 -0800997 kfree(elf_interpreter);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998out_free_ph:
999 kfree(elf_phdata);
1000 goto out;
1001}
1002
1003/* This is really simpleminded and specialized - we are loading an
1004 a.out library that is given an ELF header. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005static int load_elf_library(struct file *file)
1006{
1007 struct elf_phdr *elf_phdata;
1008 struct elf_phdr *eppnt;
1009 unsigned long elf_bss, bss, len;
1010 int retval, error, i, j;
1011 struct elfhdr elf_ex;
1012
1013 error = -ENOEXEC;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001014 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015 if (retval != sizeof(elf_ex))
1016 goto out;
1017
1018 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
1019 goto out;
1020
1021 /* First of all, some simple consistency checks */
1022 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001023 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001024 goto out;
1025
1026 /* Now read in all of the header information */
1027
1028 j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
1029 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1030
1031 error = -ENOMEM;
1032 elf_phdata = kmalloc(j, GFP_KERNEL);
1033 if (!elf_phdata)
1034 goto out;
1035
1036 eppnt = elf_phdata;
1037 error = -ENOEXEC;
1038 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
1039 if (retval != j)
1040 goto out_free_ph;
1041
1042 for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
1043 if ((eppnt + i)->p_type == PT_LOAD)
1044 j++;
1045 if (j != 1)
1046 goto out_free_ph;
1047
1048 while (eppnt->p_type != PT_LOAD)
1049 eppnt++;
1050
1051 /* Now use mmap to map the library into memory. */
Linus Torvalds6be5ceb2012-04-20 17:13:58 -07001052 error = vm_mmap(file,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053 ELF_PAGESTART(eppnt->p_vaddr),
1054 (eppnt->p_filesz +
1055 ELF_PAGEOFFSET(eppnt->p_vaddr)),
1056 PROT_READ | PROT_WRITE | PROT_EXEC,
1057 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
1058 (eppnt->p_offset -
1059 ELF_PAGEOFFSET(eppnt->p_vaddr)));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060 if (error != ELF_PAGESTART(eppnt->p_vaddr))
1061 goto out_free_ph;
1062
1063 elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
1064 if (padzero(elf_bss)) {
1065 error = -EFAULT;
1066 goto out_free_ph;
1067 }
1068
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001069 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
1070 ELF_MIN_ALIGN - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001071 bss = eppnt->p_memsz + eppnt->p_vaddr;
Linus Torvaldse4eb1ff2012-04-20 15:35:40 -07001072 if (bss > len)
1073 vm_brk(len, bss - len);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074 error = 0;
1075
1076out_free_ph:
1077 kfree(elf_phdata);
1078out:
1079 return error;
1080}
1081
Christoph Hellwig698ba7b2009-12-15 16:47:37 -08001082#ifdef CONFIG_ELF_CORE
Linus Torvalds1da177e2005-04-16 15:20:36 -07001083/*
1084 * ELF core dumper
1085 *
1086 * Modelled on fs/exec.c:aout_core_dump()
1087 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1088 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001089
1090/*
Jason Baron909af762012-03-23 15:02:51 -07001091 * The purpose of always_dump_vma() is to make sure that special kernel mappings
1092 * that are useful for post-mortem analysis are included in every core dump.
1093 * In that way we ensure that the core dump is fully interpretable later
1094 * without matching up the same kernel and hardware config to see what PC values
1095 * meant. These special mappings include - vDSO, vsyscall, and other
1096 * architecture specific mappings
1097 */
1098static bool always_dump_vma(struct vm_area_struct *vma)
1099{
1100 /* Any vsyscall mappings? */
1101 if (vma == get_gate_vma(vma->vm_mm))
1102 return true;
1103 /*
1104 * arch_vma_name() returns non-NULL for special architecture mappings,
1105 * such as vDSO sections.
1106 */
1107 if (arch_vma_name(vma))
1108 return true;
1109
1110 return false;
1111}
1112
1113/*
Roland McGrath82df3972007-10-16 23:27:02 -07001114 * Decide what to dump of a segment, part, all or none.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001115 */
Roland McGrath82df3972007-10-16 23:27:02 -07001116static unsigned long vma_dump_size(struct vm_area_struct *vma,
1117 unsigned long mm_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118{
KOSAKI Motohiroe575f112008-10-18 20:27:08 -07001119#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1120
Jason Baron909af762012-03-23 15:02:51 -07001121 /* always dump the vdso and vsyscall sections */
1122 if (always_dump_vma(vma))
Roland McGrath82df3972007-10-16 23:27:02 -07001123 goto whole;
Roland McGrathe5b97dd2007-01-26 00:56:48 -08001124
Konstantin Khlebnikov0103bd12012-10-08 16:28:59 -07001125 if (vma->vm_flags & VM_DONTDUMP)
Jason Baronaccb61f2012-03-23 15:02:51 -07001126 return 0;
1127
KOSAKI Motohiroe575f112008-10-18 20:27:08 -07001128 /* Hugetlb memory check */
1129 if (vma->vm_flags & VM_HUGETLB) {
1130 if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
1131 goto whole;
1132 if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
1133 goto whole;
1134 }
1135
Linus Torvalds1da177e2005-04-16 15:20:36 -07001136 /* Do not dump I/O mapped devices or special mappings */
Konstantin Khlebnikov314e51b2012-10-08 16:29:02 -07001137 if (vma->vm_flags & VM_IO)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001138 return 0;
1139
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001140 /* By default, dump shared memory if mapped from an anonymous file. */
1141 if (vma->vm_flags & VM_SHARED) {
Roland McGrath82df3972007-10-16 23:27:02 -07001142 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ?
1143 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
1144 goto whole;
1145 return 0;
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001146 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001147
Roland McGrath82df3972007-10-16 23:27:02 -07001148 /* Dump segments that have been written to. */
1149 if (vma->anon_vma && FILTER(ANON_PRIVATE))
1150 goto whole;
1151 if (vma->vm_file == NULL)
1152 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001153
Roland McGrath82df3972007-10-16 23:27:02 -07001154 if (FILTER(MAPPED_PRIVATE))
1155 goto whole;
1156
1157 /*
1158 * If this looks like the beginning of a DSO or executable mapping,
1159 * check for an ELF header. If we find one, dump the first page to
1160 * aid in determining what was mapped here.
1161 */
Roland McGrath92dc07b2009-02-06 17:34:07 -08001162 if (FILTER(ELF_HEADERS) &&
1163 vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
Roland McGrath82df3972007-10-16 23:27:02 -07001164 u32 __user *header = (u32 __user *) vma->vm_start;
1165 u32 word;
Roland McGrath92dc07b2009-02-06 17:34:07 -08001166 mm_segment_t fs = get_fs();
Roland McGrath82df3972007-10-16 23:27:02 -07001167 /*
1168 * Doing it this way gets the constant folded by GCC.
1169 */
1170 union {
1171 u32 cmp;
1172 char elfmag[SELFMAG];
1173 } magic;
1174 BUILD_BUG_ON(SELFMAG != sizeof word);
1175 magic.elfmag[EI_MAG0] = ELFMAG0;
1176 magic.elfmag[EI_MAG1] = ELFMAG1;
1177 magic.elfmag[EI_MAG2] = ELFMAG2;
1178 magic.elfmag[EI_MAG3] = ELFMAG3;
Roland McGrath92dc07b2009-02-06 17:34:07 -08001179 /*
1180 * Switch to the user "segment" for get_user(),
1181 * then put back what elf_core_dump() had in place.
1182 */
1183 set_fs(USER_DS);
1184 if (unlikely(get_user(word, header)))
1185 word = 0;
1186 set_fs(fs);
1187 if (word == magic.cmp)
Roland McGrath82df3972007-10-16 23:27:02 -07001188 return PAGE_SIZE;
1189 }
1190
1191#undef FILTER
1192
1193 return 0;
1194
1195whole:
1196 return vma->vm_end - vma->vm_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001197}
1198
Linus Torvalds1da177e2005-04-16 15:20:36 -07001199/* An ELF note in memory */
1200struct memelfnote
1201{
1202 const char *name;
1203 int type;
1204 unsigned int datasz;
1205 void *data;
1206};
1207
1208static int notesize(struct memelfnote *en)
1209{
1210 int sz;
1211
1212 sz = sizeof(struct elf_note);
1213 sz += roundup(strlen(en->name) + 1, 4);
1214 sz += roundup(en->datasz, 4);
1215
1216 return sz;
1217}
1218
Andi Kleend025c9d2006-09-30 23:29:28 -07001219#define DUMP_WRITE(addr, nr, foffset) \
1220 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001221
Andi Kleend025c9d2006-09-30 23:29:28 -07001222static int alignfile(struct file *file, loff_t *foffset)
1223{
Petr Vandroveca7a0d862006-10-13 18:42:07 +02001224 static const char buf[4] = { 0, };
Andi Kleend025c9d2006-09-30 23:29:28 -07001225 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
1226 return 1;
1227}
1228
1229static int writenote(struct memelfnote *men, struct file *file,
1230 loff_t *foffset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001231{
1232 struct elf_note en;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233 en.n_namesz = strlen(men->name) + 1;
1234 en.n_descsz = men->datasz;
1235 en.n_type = men->type;
1236
Andi Kleend025c9d2006-09-30 23:29:28 -07001237 DUMP_WRITE(&en, sizeof(en), foffset);
1238 DUMP_WRITE(men->name, en.n_namesz, foffset);
1239 if (!alignfile(file, foffset))
1240 return 0;
1241 DUMP_WRITE(men->data, men->datasz, foffset);
1242 if (!alignfile(file, foffset))
1243 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001244
1245 return 1;
1246}
1247#undef DUMP_WRITE
Linus Torvalds1da177e2005-04-16 15:20:36 -07001248
Roland McGrath3aba4812008-01-30 13:31:44 +01001249static void fill_elf_header(struct elfhdr *elf, int segs,
1250 u16 machine, u32 flags, u8 osabi)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001251{
Cyrill Gorcunov6970c8e2008-04-29 01:01:18 -07001252 memset(elf, 0, sizeof(*elf));
1253
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1255 elf->e_ident[EI_CLASS] = ELF_CLASS;
1256 elf->e_ident[EI_DATA] = ELF_DATA;
1257 elf->e_ident[EI_VERSION] = EV_CURRENT;
1258 elf->e_ident[EI_OSABI] = ELF_OSABI;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259
1260 elf->e_type = ET_CORE;
Roland McGrath3aba4812008-01-30 13:31:44 +01001261 elf->e_machine = machine;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262 elf->e_version = EV_CURRENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263 elf->e_phoff = sizeof(struct elfhdr);
Roland McGrath3aba4812008-01-30 13:31:44 +01001264 elf->e_flags = flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001265 elf->e_ehsize = sizeof(struct elfhdr);
1266 elf->e_phentsize = sizeof(struct elf_phdr);
1267 elf->e_phnum = segs;
Cyrill Gorcunov6970c8e2008-04-29 01:01:18 -07001268
Linus Torvalds1da177e2005-04-16 15:20:36 -07001269 return;
1270}
1271
Andrew Morton8d6b5eee2006-09-25 23:32:04 -07001272static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001273{
1274 phdr->p_type = PT_NOTE;
1275 phdr->p_offset = offset;
1276 phdr->p_vaddr = 0;
1277 phdr->p_paddr = 0;
1278 phdr->p_filesz = sz;
1279 phdr->p_memsz = 0;
1280 phdr->p_flags = 0;
1281 phdr->p_align = 0;
1282 return;
1283}
1284
1285static void fill_note(struct memelfnote *note, const char *name, int type,
1286 unsigned int sz, void *data)
1287{
1288 note->name = name;
1289 note->type = type;
1290 note->datasz = sz;
1291 note->data = data;
1292 return;
1293}
1294
1295/*
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001296 * fill up all the fields in prstatus from the given task struct, except
1297 * registers which need to be filled up separately.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001298 */
1299static void fill_prstatus(struct elf_prstatus *prstatus,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001300 struct task_struct *p, long signr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301{
1302 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1303 prstatus->pr_sigpend = p->pending.signal.sig[0];
1304 prstatus->pr_sighold = p->blocked.sig[0];
Oleg Nesterov3b34fc52009-06-17 16:27:38 -07001305 rcu_read_lock();
1306 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1307 rcu_read_unlock();
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001308 prstatus->pr_pid = task_pid_vnr(p);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001309 prstatus->pr_pgrp = task_pgrp_vnr(p);
1310 prstatus->pr_sid = task_session_vnr(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001311 if (thread_group_leader(p)) {
Frank Mayharf06febc2008-09-12 09:54:39 -07001312 struct task_cputime cputime;
1313
Linus Torvalds1da177e2005-04-16 15:20:36 -07001314 /*
Frank Mayharf06febc2008-09-12 09:54:39 -07001315 * This is the record for the group leader. It shows the
1316 * group-wide total, not its individual thread total.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001317 */
Frank Mayharf06febc2008-09-12 09:54:39 -07001318 thread_group_cputime(p, &cputime);
1319 cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
1320 cputime_to_timeval(cputime.stime, &prstatus->pr_stime);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001321 } else {
1322 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1323 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1324 }
1325 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1326 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1327}
1328
1329static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1330 struct mm_struct *mm)
1331{
David Howellsc69e8d92008-11-14 10:39:19 +11001332 const struct cred *cred;
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -07001333 unsigned int i, len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001334
1335 /* first copy the parameters from user space */
1336 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1337
1338 len = mm->arg_end - mm->arg_start;
1339 if (len >= ELF_PRARGSZ)
1340 len = ELF_PRARGSZ-1;
1341 if (copy_from_user(&psinfo->pr_psargs,
1342 (const char __user *)mm->arg_start, len))
1343 return -EFAULT;
1344 for(i = 0; i < len; i++)
1345 if (psinfo->pr_psargs[i] == 0)
1346 psinfo->pr_psargs[i] = ' ';
1347 psinfo->pr_psargs[len] = 0;
1348
Oleg Nesterov3b34fc52009-06-17 16:27:38 -07001349 rcu_read_lock();
1350 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1351 rcu_read_unlock();
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001352 psinfo->pr_pid = task_pid_vnr(p);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001353 psinfo->pr_pgrp = task_pgrp_vnr(p);
1354 psinfo->pr_sid = task_session_vnr(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001355
1356 i = p->state ? ffz(~p->state) + 1 : 0;
1357 psinfo->pr_state = i;
Carsten Otte55148542006-03-25 03:08:22 -08001358 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001359 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1360 psinfo->pr_nice = task_nice(p);
1361 psinfo->pr_flag = p->flags;
David Howellsc69e8d92008-11-14 10:39:19 +11001362 rcu_read_lock();
1363 cred = __task_cred(p);
Eric W. Biedermanebc887b2012-02-07 18:36:10 -08001364 SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid));
1365 SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid));
David Howellsc69e8d92008-11-14 10:39:19 +11001366 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001367 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1368
1369 return 0;
1370}
1371
Roland McGrath3aba4812008-01-30 13:31:44 +01001372static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
1373{
1374 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
1375 int i = 0;
1376 do
1377 i += 2;
1378 while (auxv[i - 2] != AT_NULL);
1379 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
1380}
1381
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001382static void fill_siginfo_note(struct memelfnote *note, user_siginfo_t *csigdata,
1383 siginfo_t *siginfo)
1384{
1385 mm_segment_t old_fs = get_fs();
1386 set_fs(KERNEL_DS);
1387 copy_siginfo_to_user((user_siginfo_t __user *) csigdata, siginfo);
1388 set_fs(old_fs);
1389 fill_note(note, "CORE", NT_SIGINFO, sizeof(*csigdata), csigdata);
1390}
1391
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001392#define MAX_FILE_NOTE_SIZE (4*1024*1024)
1393/*
1394 * Format of NT_FILE note:
1395 *
1396 * long count -- how many files are mapped
1397 * long page_size -- units for file_ofs
1398 * array of [COUNT] elements of
1399 * long start
1400 * long end
1401 * long file_ofs
1402 * followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL...
1403 */
1404static void fill_files_note(struct memelfnote *note)
1405{
1406 struct vm_area_struct *vma;
1407 unsigned count, size, names_ofs, remaining, n;
1408 user_long_t *data;
1409 user_long_t *start_end_ofs;
1410 char *name_base, *name_curpos;
1411
1412 /* *Estimated* file count and total data size needed */
1413 count = current->mm->map_count;
1414 size = count * 64;
1415
1416 names_ofs = (2 + 3 * count) * sizeof(data[0]);
1417 alloc:
1418 if (size >= MAX_FILE_NOTE_SIZE) /* paranoia check */
1419 goto err;
1420 size = round_up(size, PAGE_SIZE);
1421 data = vmalloc(size);
1422 if (!data)
1423 goto err;
1424
1425 start_end_ofs = data + 2;
1426 name_base = name_curpos = ((char *)data) + names_ofs;
1427 remaining = size - names_ofs;
1428 count = 0;
1429 for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
1430 struct file *file;
1431 const char *filename;
1432
1433 file = vma->vm_file;
1434 if (!file)
1435 continue;
1436 filename = d_path(&file->f_path, name_curpos, remaining);
1437 if (IS_ERR(filename)) {
1438 if (PTR_ERR(filename) == -ENAMETOOLONG) {
1439 vfree(data);
1440 size = size * 5 / 4;
1441 goto alloc;
1442 }
1443 continue;
1444 }
1445
1446 /* d_path() fills at the end, move name down */
1447 /* n = strlen(filename) + 1: */
1448 n = (name_curpos + remaining) - filename;
1449 remaining = filename - name_curpos;
1450 memmove(name_curpos, filename, n);
1451 name_curpos += n;
1452
1453 *start_end_ofs++ = vma->vm_start;
1454 *start_end_ofs++ = vma->vm_end;
1455 *start_end_ofs++ = vma->vm_pgoff;
1456 count++;
1457 }
1458
1459 /* Now we know exact count of files, can store it */
1460 data[0] = count;
1461 data[1] = PAGE_SIZE;
1462 /*
1463 * Count usually is less than current->mm->map_count,
1464 * we need to move filenames down.
1465 */
1466 n = current->mm->map_count - count;
1467 if (n != 0) {
1468 unsigned shift_bytes = n * 3 * sizeof(data[0]);
1469 memmove(name_base - shift_bytes, name_base,
1470 name_curpos - name_base);
1471 name_curpos -= shift_bytes;
1472 }
1473
1474 size = name_curpos - (char *)data;
1475 fill_note(note, "CORE", NT_FILE, size, data);
1476 err: ;
1477}
1478
Roland McGrath4206d3a2008-01-30 13:31:45 +01001479#ifdef CORE_DUMP_USE_REGSET
1480#include <linux/regset.h>
1481
1482struct elf_thread_core_info {
1483 struct elf_thread_core_info *next;
1484 struct task_struct *task;
1485 struct elf_prstatus prstatus;
1486 struct memelfnote notes[0];
1487};
1488
1489struct elf_note_info {
1490 struct elf_thread_core_info *thread;
1491 struct memelfnote psinfo;
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001492 struct memelfnote signote;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001493 struct memelfnote auxv;
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001494 struct memelfnote files;
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001495 user_siginfo_t csigdata;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001496 size_t size;
1497 int thread_notes;
1498};
1499
Roland McGrathd31472b2008-03-04 14:28:30 -08001500/*
1501 * When a regset has a writeback hook, we call it on each thread before
1502 * dumping user memory. On register window machines, this makes sure the
1503 * user memory backing the register data is up to date before we read it.
1504 */
1505static void do_thread_regset_writeback(struct task_struct *task,
1506 const struct user_regset *regset)
1507{
1508 if (regset->writeback)
1509 regset->writeback(task, regset, 1);
1510}
1511
H. J. Lu0953f65d2012-02-14 13:34:52 -08001512#ifndef PR_REG_SIZE
1513#define PR_REG_SIZE(S) sizeof(S)
1514#endif
1515
1516#ifndef PRSTATUS_SIZE
1517#define PRSTATUS_SIZE(S) sizeof(S)
1518#endif
1519
1520#ifndef PR_REG_PTR
1521#define PR_REG_PTR(S) (&((S)->pr_reg))
1522#endif
1523
1524#ifndef SET_PR_FPVALID
1525#define SET_PR_FPVALID(S, V) ((S)->pr_fpvalid = (V))
1526#endif
1527
Roland McGrath4206d3a2008-01-30 13:31:45 +01001528static int fill_thread_core_info(struct elf_thread_core_info *t,
1529 const struct user_regset_view *view,
1530 long signr, size_t *total)
1531{
1532 unsigned int i;
1533
1534 /*
1535 * NT_PRSTATUS is the one special case, because the regset data
1536 * goes into the pr_reg field inside the note contents, rather
1537 * than being the whole note contents. We fill the reset in here.
1538 * We assume that regset 0 is NT_PRSTATUS.
1539 */
1540 fill_prstatus(&t->prstatus, t->task, signr);
1541 (void) view->regsets[0].get(t->task, &view->regsets[0],
H. J. Lu0953f65d2012-02-14 13:34:52 -08001542 0, PR_REG_SIZE(t->prstatus.pr_reg),
1543 PR_REG_PTR(&t->prstatus), NULL);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001544
1545 fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
H. J. Lu0953f65d2012-02-14 13:34:52 -08001546 PRSTATUS_SIZE(t->prstatus), &t->prstatus);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001547 *total += notesize(&t->notes[0]);
1548
Roland McGrathd31472b2008-03-04 14:28:30 -08001549 do_thread_regset_writeback(t->task, &view->regsets[0]);
1550
Roland McGrath4206d3a2008-01-30 13:31:45 +01001551 /*
1552 * Each other regset might generate a note too. For each regset
1553 * that has no core_note_type or is inactive, we leave t->notes[i]
1554 * all zero and we'll know to skip writing it later.
1555 */
1556 for (i = 1; i < view->n; ++i) {
1557 const struct user_regset *regset = &view->regsets[i];
Roland McGrathd31472b2008-03-04 14:28:30 -08001558 do_thread_regset_writeback(t->task, regset);
H. Peter Anvinc8e25252012-03-02 10:43:48 -08001559 if (regset->core_note_type && regset->get &&
Roland McGrath4206d3a2008-01-30 13:31:45 +01001560 (!regset->active || regset->active(t->task, regset))) {
1561 int ret;
1562 size_t size = regset->n * regset->size;
1563 void *data = kmalloc(size, GFP_KERNEL);
1564 if (unlikely(!data))
1565 return 0;
1566 ret = regset->get(t->task, regset,
1567 0, size, data, NULL);
1568 if (unlikely(ret))
1569 kfree(data);
1570 else {
1571 if (regset->core_note_type != NT_PRFPREG)
1572 fill_note(&t->notes[i], "LINUX",
1573 regset->core_note_type,
1574 size, data);
1575 else {
H. J. Lu0953f65d2012-02-14 13:34:52 -08001576 SET_PR_FPVALID(&t->prstatus, 1);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001577 fill_note(&t->notes[i], "CORE",
1578 NT_PRFPREG, size, data);
1579 }
1580 *total += notesize(&t->notes[i]);
1581 }
1582 }
1583 }
1584
1585 return 1;
1586}
1587
1588static int fill_note_info(struct elfhdr *elf, int phdrs,
1589 struct elf_note_info *info,
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001590 siginfo_t *siginfo, struct pt_regs *regs)
Roland McGrath4206d3a2008-01-30 13:31:45 +01001591{
1592 struct task_struct *dump_task = current;
1593 const struct user_regset_view *view = task_user_regset_view(dump_task);
1594 struct elf_thread_core_info *t;
1595 struct elf_prpsinfo *psinfo;
Oleg Nesterov83914442008-07-25 01:47:45 -07001596 struct core_thread *ct;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001597 unsigned int i;
1598
1599 info->size = 0;
1600 info->thread = NULL;
1601
1602 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001603 if (psinfo == NULL)
1604 return 0;
1605
Amerigo Wange2dbe122009-07-01 01:06:26 -04001606 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1607
Roland McGrath4206d3a2008-01-30 13:31:45 +01001608 /*
1609 * Figure out how many notes we're going to need for each thread.
1610 */
1611 info->thread_notes = 0;
1612 for (i = 0; i < view->n; ++i)
1613 if (view->regsets[i].core_note_type != 0)
1614 ++info->thread_notes;
1615
1616 /*
1617 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1618 * since it is our one special case.
1619 */
1620 if (unlikely(info->thread_notes == 0) ||
1621 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
1622 WARN_ON(1);
1623 return 0;
1624 }
1625
1626 /*
1627 * Initialize the ELF file header.
1628 */
1629 fill_elf_header(elf, phdrs,
1630 view->e_machine, view->e_flags, view->ei_osabi);
1631
1632 /*
1633 * Allocate a structure for each thread.
1634 */
Oleg Nesterov83914442008-07-25 01:47:45 -07001635 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) {
1636 t = kzalloc(offsetof(struct elf_thread_core_info,
1637 notes[info->thread_notes]),
1638 GFP_KERNEL);
1639 if (unlikely(!t))
1640 return 0;
Oleg Nesterov24d52882008-07-25 01:47:40 -07001641
Oleg Nesterov83914442008-07-25 01:47:45 -07001642 t->task = ct->task;
1643 if (ct->task == dump_task || !info->thread) {
1644 t->next = info->thread;
1645 info->thread = t;
1646 } else {
1647 /*
1648 * Make sure to keep the original task at
1649 * the head of the list.
1650 */
1651 t->next = info->thread->next;
1652 info->thread->next = t;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001653 }
Oleg Nesterov83914442008-07-25 01:47:45 -07001654 }
Roland McGrath4206d3a2008-01-30 13:31:45 +01001655
1656 /*
1657 * Now fill in each thread's information.
1658 */
1659 for (t = info->thread; t != NULL; t = t->next)
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001660 if (!fill_thread_core_info(t, view, siginfo->si_signo, &info->size))
Roland McGrath4206d3a2008-01-30 13:31:45 +01001661 return 0;
1662
1663 /*
1664 * Fill in the two process-wide notes.
1665 */
1666 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
1667 info->size += notesize(&info->psinfo);
1668
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001669 fill_siginfo_note(&info->signote, &info->csigdata, siginfo);
1670 info->size += notesize(&info->signote);
1671
Roland McGrath4206d3a2008-01-30 13:31:45 +01001672 fill_auxv_note(&info->auxv, current->mm);
1673 info->size += notesize(&info->auxv);
1674
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001675 fill_files_note(&info->files);
1676 info->size += notesize(&info->files);
1677
Roland McGrath4206d3a2008-01-30 13:31:45 +01001678 return 1;
1679}
1680
1681static size_t get_note_info_size(struct elf_note_info *info)
1682{
1683 return info->size;
1684}
1685
1686/*
1687 * Write all the notes for each thread. When writing the first thread, the
1688 * process-wide notes are interleaved after the first thread-specific note.
1689 */
1690static int write_note_info(struct elf_note_info *info,
1691 struct file *file, loff_t *foffset)
1692{
1693 bool first = 1;
1694 struct elf_thread_core_info *t = info->thread;
1695
1696 do {
1697 int i;
1698
1699 if (!writenote(&t->notes[0], file, foffset))
1700 return 0;
1701
1702 if (first && !writenote(&info->psinfo, file, foffset))
1703 return 0;
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001704 if (first && !writenote(&info->signote, file, foffset))
1705 return 0;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001706 if (first && !writenote(&info->auxv, file, foffset))
1707 return 0;
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001708 if (first && !writenote(&info->files, file, foffset))
1709 return 0;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001710
1711 for (i = 1; i < info->thread_notes; ++i)
1712 if (t->notes[i].data &&
1713 !writenote(&t->notes[i], file, foffset))
1714 return 0;
1715
1716 first = 0;
1717 t = t->next;
1718 } while (t);
1719
1720 return 1;
1721}
1722
1723static void free_note_info(struct elf_note_info *info)
1724{
1725 struct elf_thread_core_info *threads = info->thread;
1726 while (threads) {
1727 unsigned int i;
1728 struct elf_thread_core_info *t = threads;
1729 threads = t->next;
1730 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
1731 for (i = 1; i < info->thread_notes; ++i)
1732 kfree(t->notes[i].data);
1733 kfree(t);
1734 }
1735 kfree(info->psinfo.data);
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001736 vfree(info->files.data);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001737}
1738
1739#else
1740
Linus Torvalds1da177e2005-04-16 15:20:36 -07001741/* Here is the structure in which status of each thread is captured. */
1742struct elf_thread_status
1743{
1744 struct list_head list;
1745 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1746 elf_fpregset_t fpu; /* NT_PRFPREG */
1747 struct task_struct *thread;
1748#ifdef ELF_CORE_COPY_XFPREGS
Mark Nelson5b20cd82007-10-16 23:25:39 -07001749 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001750#endif
1751 struct memelfnote notes[3];
1752 int num_notes;
1753};
1754
1755/*
1756 * In order to add the specific thread information for the elf file format,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001757 * we need to keep a linked list of every threads pr_status and then create
1758 * a single section for them in the final core file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001759 */
1760static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1761{
1762 int sz = 0;
1763 struct task_struct *p = t->thread;
1764 t->num_notes = 0;
1765
1766 fill_prstatus(&t->prstatus, p, signr);
1767 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1768
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001769 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1770 &(t->prstatus));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001771 t->num_notes++;
1772 sz += notesize(&t->notes[0]);
1773
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001774 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1775 &t->fpu))) {
1776 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1777 &(t->fpu));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001778 t->num_notes++;
1779 sz += notesize(&t->notes[1]);
1780 }
1781
1782#ifdef ELF_CORE_COPY_XFPREGS
1783 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
Mark Nelson5b20cd82007-10-16 23:25:39 -07001784 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1785 sizeof(t->xfpu), &t->xfpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001786 t->num_notes++;
1787 sz += notesize(&t->notes[2]);
1788 }
1789#endif
1790 return sz;
1791}
1792
Roland McGrath3aba4812008-01-30 13:31:44 +01001793struct elf_note_info {
1794 struct memelfnote *notes;
1795 struct elf_prstatus *prstatus; /* NT_PRSTATUS */
1796 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */
1797 struct list_head thread_list;
1798 elf_fpregset_t *fpu;
1799#ifdef ELF_CORE_COPY_XFPREGS
1800 elf_fpxregset_t *xfpu;
1801#endif
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001802 user_siginfo_t csigdata;
Roland McGrath3aba4812008-01-30 13:31:44 +01001803 int thread_status_size;
1804 int numnote;
1805};
1806
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001807static int elf_note_info_init(struct elf_note_info *info)
Roland McGrath3aba4812008-01-30 13:31:44 +01001808{
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001809 memset(info, 0, sizeof(*info));
Roland McGrath3aba4812008-01-30 13:31:44 +01001810 INIT_LIST_HEAD(&info->thread_list);
1811
Denys Vlasenko49ae4d42012-10-04 17:15:35 -07001812 /* Allocate space for ELF notes */
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001813 info->notes = kmalloc(8 * sizeof(struct memelfnote), GFP_KERNEL);
Roland McGrath3aba4812008-01-30 13:31:44 +01001814 if (!info->notes)
1815 return 0;
1816 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
1817 if (!info->psinfo)
Denys Vlasenkof34f9d12012-09-26 11:34:50 +10001818 return 0;
Roland McGrath3aba4812008-01-30 13:31:44 +01001819 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
1820 if (!info->prstatus)
Denys Vlasenkof34f9d12012-09-26 11:34:50 +10001821 return 0;
Roland McGrath3aba4812008-01-30 13:31:44 +01001822 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
1823 if (!info->fpu)
Denys Vlasenkof34f9d12012-09-26 11:34:50 +10001824 return 0;
Roland McGrath3aba4812008-01-30 13:31:44 +01001825#ifdef ELF_CORE_COPY_XFPREGS
1826 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
1827 if (!info->xfpu)
Denys Vlasenkof34f9d12012-09-26 11:34:50 +10001828 return 0;
Roland McGrath3aba4812008-01-30 13:31:44 +01001829#endif
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001830 return 1;
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001831}
Roland McGrath3aba4812008-01-30 13:31:44 +01001832
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001833static int fill_note_info(struct elfhdr *elf, int phdrs,
1834 struct elf_note_info *info,
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001835 siginfo_t *siginfo, struct pt_regs *regs)
Amerigo Wang0cf062d2009-09-23 15:57:05 -07001836{
1837 struct list_head *t;
1838
1839 if (!elf_note_info_init(info))
1840 return 0;
1841
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001842 if (siginfo->si_signo) {
Oleg Nesterov83914442008-07-25 01:47:45 -07001843 struct core_thread *ct;
WANG Cong4220b7f2008-04-29 01:01:18 -07001844 struct elf_thread_status *ets;
Oleg Nesterov24d52882008-07-25 01:47:40 -07001845
Oleg Nesterov83914442008-07-25 01:47:45 -07001846 for (ct = current->mm->core_state->dumper.next;
1847 ct; ct = ct->next) {
1848 ets = kzalloc(sizeof(*ets), GFP_KERNEL);
1849 if (!ets)
1850 return 0;
1851
1852 ets->thread = ct->task;
1853 list_add(&ets->list, &info->thread_list);
1854 }
1855
Roland McGrath3aba4812008-01-30 13:31:44 +01001856 list_for_each(t, &info->thread_list) {
Roland McGrath3aba4812008-01-30 13:31:44 +01001857 int sz;
1858
WANG Cong4220b7f2008-04-29 01:01:18 -07001859 ets = list_entry(t, struct elf_thread_status, list);
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001860 sz = elf_dump_thread_status(siginfo->si_signo, ets);
Roland McGrath3aba4812008-01-30 13:31:44 +01001861 info->thread_status_size += sz;
1862 }
1863 }
1864 /* now collect the dump for the current */
1865 memset(info->prstatus, 0, sizeof(*info->prstatus));
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07001866 fill_prstatus(info->prstatus, current, siginfo->si_signo);
Roland McGrath3aba4812008-01-30 13:31:44 +01001867 elf_core_copy_regs(&info->prstatus->pr_reg, regs);
1868
1869 /* Set up header */
1870 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI);
1871
1872 /*
1873 * Set up the notes in similar form to SVR4 core dumps made
1874 * with info from their /proc.
1875 */
1876
1877 fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
1878 sizeof(*info->prstatus), info->prstatus);
1879 fill_psinfo(info->psinfo, current->group_leader, current->mm);
1880 fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
1881 sizeof(*info->psinfo), info->psinfo);
1882
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001883 fill_siginfo_note(info->notes + 2, &info->csigdata, siginfo);
1884 fill_auxv_note(info->notes + 3, current->mm);
1885 fill_files_note(info->notes + 4);
Roland McGrath3aba4812008-01-30 13:31:44 +01001886
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001887 info->numnote = 5;
Roland McGrath3aba4812008-01-30 13:31:44 +01001888
1889 /* Try to dump the FPU. */
1890 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
1891 info->fpu);
1892 if (info->prstatus->pr_fpvalid)
1893 fill_note(info->notes + info->numnote++,
1894 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
1895#ifdef ELF_CORE_COPY_XFPREGS
1896 if (elf_core_copy_task_xfpregs(current, info->xfpu))
1897 fill_note(info->notes + info->numnote++,
1898 "LINUX", ELF_CORE_XFPREG_TYPE,
1899 sizeof(*info->xfpu), info->xfpu);
1900#endif
1901
1902 return 1;
Roland McGrath3aba4812008-01-30 13:31:44 +01001903}
1904
1905static size_t get_note_info_size(struct elf_note_info *info)
1906{
1907 int sz = 0;
1908 int i;
1909
1910 for (i = 0; i < info->numnote; i++)
1911 sz += notesize(info->notes + i);
1912
1913 sz += info->thread_status_size;
1914
1915 return sz;
1916}
1917
1918static int write_note_info(struct elf_note_info *info,
1919 struct file *file, loff_t *foffset)
1920{
1921 int i;
1922 struct list_head *t;
1923
1924 for (i = 0; i < info->numnote; i++)
1925 if (!writenote(info->notes + i, file, foffset))
1926 return 0;
1927
1928 /* write out the thread status notes section */
1929 list_for_each(t, &info->thread_list) {
1930 struct elf_thread_status *tmp =
1931 list_entry(t, struct elf_thread_status, list);
1932
1933 for (i = 0; i < tmp->num_notes; i++)
1934 if (!writenote(&tmp->notes[i], file, foffset))
1935 return 0;
1936 }
1937
1938 return 1;
1939}
1940
1941static void free_note_info(struct elf_note_info *info)
1942{
1943 while (!list_empty(&info->thread_list)) {
1944 struct list_head *tmp = info->thread_list.next;
1945 list_del(tmp);
1946 kfree(list_entry(tmp, struct elf_thread_status, list));
1947 }
1948
Denys Vlasenko2aa362c2012-10-04 17:15:36 -07001949 /* Free data allocated by fill_files_note(): */
1950 vfree(info->notes[4].data);
1951
Roland McGrath3aba4812008-01-30 13:31:44 +01001952 kfree(info->prstatus);
1953 kfree(info->psinfo);
1954 kfree(info->notes);
1955 kfree(info->fpu);
1956#ifdef ELF_CORE_COPY_XFPREGS
1957 kfree(info->xfpu);
1958#endif
1959}
1960
Roland McGrath4206d3a2008-01-30 13:31:45 +01001961#endif
1962
Roland McGrathf47aef52007-01-26 00:56:49 -08001963static struct vm_area_struct *first_vma(struct task_struct *tsk,
1964 struct vm_area_struct *gate_vma)
1965{
1966 struct vm_area_struct *ret = tsk->mm->mmap;
1967
1968 if (ret)
1969 return ret;
1970 return gate_vma;
1971}
1972/*
1973 * Helper function for iterating across a vma list. It ensures that the caller
1974 * will visit `gate_vma' prior to terminating the search.
1975 */
1976static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma,
1977 struct vm_area_struct *gate_vma)
1978{
1979 struct vm_area_struct *ret;
1980
1981 ret = this_vma->vm_next;
1982 if (ret)
1983 return ret;
1984 if (this_vma == gate_vma)
1985 return NULL;
1986 return gate_vma;
1987}
1988
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08001989static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
1990 elf_addr_t e_shoff, int segs)
1991{
1992 elf->e_shoff = e_shoff;
1993 elf->e_shentsize = sizeof(*shdr4extnum);
1994 elf->e_shnum = 1;
1995 elf->e_shstrndx = SHN_UNDEF;
1996
1997 memset(shdr4extnum, 0, sizeof(*shdr4extnum));
1998
1999 shdr4extnum->sh_type = SHT_NULL;
2000 shdr4extnum->sh_size = elf->e_shnum;
2001 shdr4extnum->sh_link = elf->e_shstrndx;
2002 shdr4extnum->sh_info = segs;
2003}
2004
2005static size_t elf_core_vma_data_size(struct vm_area_struct *gate_vma,
2006 unsigned long mm_flags)
2007{
2008 struct vm_area_struct *vma;
2009 size_t size = 0;
2010
2011 for (vma = first_vma(current, gate_vma); vma != NULL;
2012 vma = next_vma(vma, gate_vma))
2013 size += vma_dump_size(vma, mm_flags);
2014 return size;
2015}
2016
Linus Torvalds1da177e2005-04-16 15:20:36 -07002017/*
2018 * Actual dumper
2019 *
2020 * This is a two-pass process; first we find the offsets of the bits,
2021 * and then they are actually written out. If we run out of core limit
2022 * we just truncate.
2023 */
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08002024static int elf_core_dump(struct coredump_params *cprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002025{
Linus Torvalds1da177e2005-04-16 15:20:36 -07002026 int has_dumped = 0;
2027 mm_segment_t fs;
2028 int segs;
2029 size_t size = 0;
Roland McGrathf47aef52007-01-26 00:56:49 -08002030 struct vm_area_struct *vma, *gate_vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002031 struct elfhdr *elf = NULL;
Andi Kleend025c9d2006-09-30 23:29:28 -07002032 loff_t offset = 0, dataoff, foffset;
Roland McGrath3aba4812008-01-30 13:31:44 +01002033 struct elf_note_info info;
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002034 struct elf_phdr *phdr4note = NULL;
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002035 struct elf_shdr *shdr4extnum = NULL;
2036 Elf_Half e_phnum;
2037 elf_addr_t e_shoff;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002038
2039 /*
2040 * We no longer stop all VM operations.
2041 *
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002042 * This is because those proceses that could possibly change map_count
2043 * or the mmap / vma pages are now blocked in do_exit on current
2044 * finishing this core dump.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002045 *
2046 * Only ptrace can touch these memory addresses, but it doesn't change
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002047 * the map_count or the pages allocated. So no possibility of crashing
Linus Torvalds1da177e2005-04-16 15:20:36 -07002048 * exists while dumping the mm->vm_next areas to the core file.
2049 */
2050
2051 /* alloc memory for large data structures: too large to be on stack */
2052 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
2053 if (!elf)
WANG Cong5f719552008-05-06 12:45:35 +08002054 goto out;
KAMEZAWA Hiroyuki341c87b2009-06-30 11:41:23 -07002055 /*
2056 * The number of segs are recored into ELF header as 16bit value.
2057 * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
2058 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002059 segs = current->mm->map_count;
Daisuke HATAYAMA1fcccba2010-03-05 13:44:07 -08002060 segs += elf_core_extra_phdrs();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002061
Stephen Wilson31db58b2011-03-13 15:49:15 -04002062 gate_vma = get_gate_vma(current->mm);
Roland McGrathf47aef52007-01-26 00:56:49 -08002063 if (gate_vma != NULL)
2064 segs++;
2065
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002066 /* for notes section */
2067 segs++;
2068
2069 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
2070 * this, kernel supports extended numbering. Have a look at
2071 * include/linux/elf.h for further information. */
2072 e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
2073
Roland McGrath3aba4812008-01-30 13:31:44 +01002074 /*
2075 * Collect all the non-memory information about the process for the
2076 * notes. This also sets up the file header.
2077 */
Denys Vlasenko5ab1c302012-10-04 17:15:29 -07002078 if (!fill_note_info(elf, e_phnum, &info, cprm->siginfo, cprm->regs))
Roland McGrath3aba4812008-01-30 13:31:44 +01002079 goto cleanup;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002080
2081 has_dumped = 1;
2082 current->flags |= PF_DUMPCORE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002083
2084 fs = get_fs();
2085 set_fs(KERNEL_DS);
2086
Linus Torvalds1da177e2005-04-16 15:20:36 -07002087 offset += sizeof(*elf); /* Elf header */
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002088 offset += segs * sizeof(struct elf_phdr); /* Program headers */
Petr Vandroveca7a0d862006-10-13 18:42:07 +02002089 foffset = offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002090
2091 /* Write notes phdr entry */
2092 {
Roland McGrath3aba4812008-01-30 13:31:44 +01002093 size_t sz = get_note_info_size(&info);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002094
Michael Ellermane5501492007-09-19 14:38:12 +10002095 sz += elf_coredump_extra_notes_size();
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01002096
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002097 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
2098 if (!phdr4note)
Daisuke HATAYAMA088e7af2010-03-05 13:44:06 -08002099 goto end_coredump;
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002100
2101 fill_elf_note_phdr(phdr4note, sz, offset);
2102 offset += sz;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002103 }
2104
Linus Torvalds1da177e2005-04-16 15:20:36 -07002105 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
2106
Masami Hiramatsu30736a42010-03-05 13:44:12 -08002107 offset += elf_core_vma_data_size(gate_vma, cprm->mm_flags);
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002108 offset += elf_core_extra_data_size();
2109 e_shoff = offset;
2110
2111 if (e_phnum == PN_XNUM) {
2112 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
2113 if (!shdr4extnum)
2114 goto end_coredump;
2115 fill_extnum_info(elf, shdr4extnum, e_shoff, segs);
2116 }
2117
2118 offset = dataoff;
2119
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002120 size += sizeof(*elf);
2121 if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
2122 goto end_coredump;
2123
2124 size += sizeof(*phdr4note);
2125 if (size > cprm->limit
2126 || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note)))
2127 goto end_coredump;
2128
Linus Torvalds1da177e2005-04-16 15:20:36 -07002129 /* Write program headers for segments dump */
Roland McGrathf47aef52007-01-26 00:56:49 -08002130 for (vma = first_vma(current, gate_vma); vma != NULL;
2131 vma = next_vma(vma, gate_vma)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002132 struct elf_phdr phdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002133
2134 phdr.p_type = PT_LOAD;
2135 phdr.p_offset = offset;
2136 phdr.p_vaddr = vma->vm_start;
2137 phdr.p_paddr = 0;
Masami Hiramatsu30736a42010-03-05 13:44:12 -08002138 phdr.p_filesz = vma_dump_size(vma, cprm->mm_flags);
Roland McGrath82df3972007-10-16 23:27:02 -07002139 phdr.p_memsz = vma->vm_end - vma->vm_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002140 offset += phdr.p_filesz;
2141 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002142 if (vma->vm_flags & VM_WRITE)
2143 phdr.p_flags |= PF_W;
2144 if (vma->vm_flags & VM_EXEC)
2145 phdr.p_flags |= PF_X;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002146 phdr.p_align = ELF_EXEC_PAGESIZE;
2147
Daisuke HATAYAMA088e7af2010-03-05 13:44:06 -08002148 size += sizeof(phdr);
2149 if (size > cprm->limit
2150 || !dump_write(cprm->file, &phdr, sizeof(phdr)))
2151 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002152 }
2153
Daisuke HATAYAMA1fcccba2010-03-05 13:44:07 -08002154 if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit))
2155 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002156
2157 /* write out the notes section */
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08002158 if (!write_note_info(&info, cprm->file, &foffset))
Roland McGrath3aba4812008-01-30 13:31:44 +01002159 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002160
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08002161 if (elf_coredump_extra_notes_write(cprm->file, &foffset))
Michael Ellermane5501492007-09-19 14:38:12 +10002162 goto end_coredump;
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01002163
Andi Kleend025c9d2006-09-30 23:29:28 -07002164 /* Align to page */
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08002165 if (!dump_seek(cprm->file, dataoff - foffset))
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002166 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002167
Roland McGrathf47aef52007-01-26 00:56:49 -08002168 for (vma = first_vma(current, gate_vma); vma != NULL;
2169 vma = next_vma(vma, gate_vma)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002170 unsigned long addr;
Roland McGrath82df3972007-10-16 23:27:02 -07002171 unsigned long end;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002172
Masami Hiramatsu30736a42010-03-05 13:44:12 -08002173 end = vma->vm_start + vma_dump_size(vma, cprm->mm_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002174
Roland McGrath82df3972007-10-16 23:27:02 -07002175 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002176 struct page *page;
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002177 int stop;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002178
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002179 page = get_dump_page(addr);
2180 if (page) {
2181 void *kaddr = kmap(page);
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08002182 stop = ((size += PAGE_SIZE) > cprm->limit) ||
2183 !dump_write(cprm->file, kaddr,
2184 PAGE_SIZE);
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002185 kunmap(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002186 page_cache_release(page);
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002187 } else
Masami Hiramatsuf6151df2009-12-17 15:27:16 -08002188 stop = !dump_seek(cprm->file, PAGE_SIZE);
Hugh Dickinsf3e8fcc2009-09-21 17:03:25 -07002189 if (stop)
2190 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002191 }
2192 }
2193
Daisuke HATAYAMA1fcccba2010-03-05 13:44:07 -08002194 if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit))
2195 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002196
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002197 if (e_phnum == PN_XNUM) {
2198 size += sizeof(*shdr4extnum);
2199 if (size > cprm->limit
2200 || !dump_write(cprm->file, shdr4extnum,
2201 sizeof(*shdr4extnum)))
2202 goto end_coredump;
2203 }
2204
Linus Torvalds1da177e2005-04-16 15:20:36 -07002205end_coredump:
2206 set_fs(fs);
2207
2208cleanup:
Roland McGrath3aba4812008-01-30 13:31:44 +01002209 free_note_info(&info);
Daisuke HATAYAMA8d9032b2010-03-05 13:44:10 -08002210 kfree(shdr4extnum);
Daisuke HATAYAMA93eb2112010-03-05 13:44:09 -08002211 kfree(phdr4note);
WANG Cong5f719552008-05-06 12:45:35 +08002212 kfree(elf);
2213out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002214 return has_dumped;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002215}
2216
Christoph Hellwig698ba7b2009-12-15 16:47:37 -08002217#endif /* CONFIG_ELF_CORE */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002218
2219static int __init init_elf_binfmt(void)
2220{
Al Viro8fc3dc52012-03-17 03:05:16 -04002221 register_binfmt(&elf_format);
2222 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002223}
2224
2225static void __exit exit_elf_binfmt(void)
2226{
2227 /* Remove the COFF and ELF loaders. */
2228 unregister_binfmt(&elf_format);
2229}
2230
2231core_initcall(init_elf_binfmt);
2232module_exit(exit_elf_binfmt);
2233MODULE_LICENSE("GPL");