blob: 8fcfa398d35075e1e149b70d62226a6095524ad3 [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>
15#include <linux/stat.h>
16#include <linux/time.h>
17#include <linux/mm.h>
18#include <linux/mman.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/errno.h>
20#include <linux/signal.h>
21#include <linux/binfmts.h>
22#include <linux/string.h>
23#include <linux/file.h>
24#include <linux/fcntl.h>
25#include <linux/ptrace.h>
26#include <linux/slab.h>
27#include <linux/shm.h>
28#include <linux/personality.h>
29#include <linux/elfcore.h>
30#include <linux/init.h>
31#include <linux/highuid.h>
32#include <linux/smp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/compiler.h>
34#include <linux/highmem.h>
35#include <linux/pagemap.h>
36#include <linux/security.h>
37#include <linux/syscalls.h>
38#include <linux/random.h>
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070039#include <linux/elf.h>
Alexey Dobriyan7e80d0d2007-05-08 00:28:59 -070040#include <linux/utsname.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041#include <asm/uaccess.h>
42#include <asm/param.h>
43#include <asm/page.h>
44
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070045static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs);
46static int load_elf_library(struct file *);
Andrew Mortonbb1ad822008-01-30 13:31:07 +010047static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *,
48 int, int, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
Linus Torvalds1da177e2005-04-16 15:20:36 -070050/*
51 * If we don't support core dumping, then supply a NULL so we
52 * don't even try.
53 */
Matt Mackall708e9a72006-01-08 01:05:25 -080054#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
Neil Horman7dc0b222007-10-16 23:26:34 -070055static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);
Linus Torvalds1da177e2005-04-16 15:20:36 -070056#else
57#define elf_core_dump NULL
58#endif
59
60#if ELF_EXEC_PAGESIZE > PAGE_SIZE
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070061#define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
Linus Torvalds1da177e2005-04-16 15:20:36 -070062#else
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070063#define ELF_MIN_ALIGN PAGE_SIZE
Linus Torvalds1da177e2005-04-16 15:20:36 -070064#endif
65
66#ifndef ELF_CORE_EFLAGS
67#define ELF_CORE_EFLAGS 0
68#endif
69
70#define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
71#define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
72#define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
73
74static struct linux_binfmt elf_format = {
75 .module = THIS_MODULE,
76 .load_binary = load_elf_binary,
77 .load_shlib = load_elf_library,
78 .core_dump = elf_core_dump,
Andi Kleen9fbbd4d2007-02-13 13:26:26 +010079 .min_coredump = ELF_EXEC_PAGESIZE,
80 .hasvdso = 1
Linus Torvalds1da177e2005-04-16 15:20:36 -070081};
82
Andrew Mortond4e3cc32007-07-21 04:37:32 -070083#define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
Linus Torvalds1da177e2005-04-16 15:20:36 -070084
85static int set_brk(unsigned long start, unsigned long end)
86{
87 start = ELF_PAGEALIGN(start);
88 end = ELF_PAGEALIGN(end);
89 if (end > start) {
90 unsigned long addr;
91 down_write(&current->mm->mmap_sem);
92 addr = do_brk(start, end - start);
93 up_write(&current->mm->mmap_sem);
94 if (BAD_ADDR(addr))
95 return addr;
96 }
97 current->mm->start_brk = current->mm->brk = end;
98 return 0;
99}
100
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101/* We need to explicitly zero any fractional pages
102 after the data section (i.e. bss). This would
103 contain the junk from the file that should not
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700104 be in memory
105 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106static int padzero(unsigned long elf_bss)
107{
108 unsigned long nbyte;
109
110 nbyte = ELF_PAGEOFFSET(elf_bss);
111 if (nbyte) {
112 nbyte = ELF_MIN_ALIGN - nbyte;
113 if (clear_user((void __user *) elf_bss, nbyte))
114 return -EFAULT;
115 }
116 return 0;
117}
118
Ohad Ben-Cohen09c6dd32008-02-03 18:05:15 +0200119/* Let's use some macros to make this stack manipulation a little clearer */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120#ifdef CONFIG_STACK_GROWSUP
121#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
122#define STACK_ROUND(sp, items) \
123 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700124#define STACK_ALLOC(sp, len) ({ \
125 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
126 old_sp; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127#else
128#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
129#define STACK_ROUND(sp, items) \
130 (((unsigned long) (sp - items)) &~ 15UL)
131#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
132#endif
133
Nathan Lynch483fad12008-07-22 04:48:46 +1000134#ifndef ELF_BASE_PLATFORM
135/*
136 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
137 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
138 * will be copied to the user stack in the same manner as AT_PLATFORM.
139 */
140#define ELF_BASE_PLATFORM NULL
141#endif
142
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143static int
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700144create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
Andi Kleend20894a2008-02-08 04:21:54 -0800145 unsigned long load_addr, unsigned long interp_load_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146{
147 unsigned long p = bprm->p;
148 int argc = bprm->argc;
149 int envc = bprm->envc;
150 elf_addr_t __user *argv;
151 elf_addr_t __user *envp;
152 elf_addr_t __user *sp;
153 elf_addr_t __user *u_platform;
Nathan Lynch483fad12008-07-22 04:48:46 +1000154 elf_addr_t __user *u_base_platform;
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;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 int items;
158 elf_addr_t *elf_info;
159 int ei_index = 0;
160 struct task_struct *tsk = current;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700161 struct vm_area_struct *vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162
163 /*
Franck Bui-Huud68c9d62007-10-16 23:30:24 -0700164 * In some cases (e.g. Hyper-Threading), we want to avoid L1
165 * evictions by the processes running on the same package. One
166 * thing we can do is to shuffle the initial stack for them.
167 */
168
169 p = arch_align_stack(p);
170
171 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 * If this architecture has a platform capability string, copy it
173 * to userspace. In some cases (Sparc), this info is impossible
174 * for userspace to get any other way, in others (i386) it is
175 * merely difficult.
176 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177 u_platform = NULL;
178 if (k_platform) {
179 size_t len = strlen(k_platform) + 1;
180
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
182 if (__copy_to_user(u_platform, k_platform, len))
183 return -EFAULT;
184 }
185
Nathan Lynch483fad12008-07-22 04:48:46 +1000186 /*
187 * If this architecture has a "base" platform capability
188 * string, copy it to userspace.
189 */
190 u_base_platform = NULL;
191 if (k_base_platform) {
192 size_t len = strlen(k_base_platform) + 1;
193
194 u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
195 if (__copy_to_user(u_base_platform, k_base_platform, len))
196 return -EFAULT;
197 }
198
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 /* Create the ELF interpreter info */
Jesper Juhl785d5572006-06-23 02:05:35 -0700200 elf_info = (elf_addr_t *)current->mm->saved_auxv;
Olaf Hering4f9a58d2007-10-16 23:30:12 -0700201 /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202#define NEW_AUX_ENT(id, val) \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700203 do { \
Jesper Juhl785d5572006-06-23 02:05:35 -0700204 elf_info[ei_index++] = id; \
205 elf_info[ei_index++] = val; \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700206 } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207
208#ifdef ARCH_DLINFO
209 /*
210 * ARCH_DLINFO must come first so PPC can do its special alignment of
211 * AUXV.
Olaf Hering4f9a58d2007-10-16 23:30:12 -0700212 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
213 * ARCH_DLINFO changes
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214 */
215 ARCH_DLINFO;
216#endif
217 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
218 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
219 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
220 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700221 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
223 NEW_AUX_ENT(AT_BASE, interp_load_addr);
224 NEW_AUX_ENT(AT_FLAGS, 0);
225 NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
Jesper Juhl785d5572006-06-23 02:05:35 -0700226 NEW_AUX_ENT(AT_UID, tsk->uid);
227 NEW_AUX_ENT(AT_EUID, tsk->euid);
228 NEW_AUX_ENT(AT_GID, tsk->gid);
229 NEW_AUX_ENT(AT_EGID, tsk->egid);
230 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
John Reiser65191082008-07-21 14:21:32 -0700231 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 if (k_platform) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700233 NEW_AUX_ENT(AT_PLATFORM,
Jesper Juhl785d5572006-06-23 02:05:35 -0700234 (elf_addr_t)(unsigned long)u_platform);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 }
Nathan Lynch483fad12008-07-22 04:48:46 +1000236 if (k_base_platform) {
237 NEW_AUX_ENT(AT_BASE_PLATFORM,
238 (elf_addr_t)(unsigned long)u_base_platform);
239 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
Jesper Juhl785d5572006-06-23 02:05:35 -0700241 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 }
243#undef NEW_AUX_ENT
244 /* AT_NULL is zero; clear the rest too */
245 memset(&elf_info[ei_index], 0,
246 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
247
248 /* And advance past the AT_NULL entry. */
249 ei_index += 2;
250
251 sp = STACK_ADD(p, ei_index);
252
Andi Kleend20894a2008-02-08 04:21:54 -0800253 items = (argc + 1) + (envc + 1) + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 bprm->p = STACK_ROUND(sp, items);
255
256 /* Point sp at the lowest address on the stack */
257#ifdef CONFIG_STACK_GROWSUP
258 sp = (elf_addr_t __user *)bprm->p - items - ei_index;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700259 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260#else
261 sp = (elf_addr_t __user *)bprm->p;
262#endif
263
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700264
265 /*
266 * Grow the stack manually; some architectures have a limit on how
267 * far ahead a user-space access may be in order to grow the stack.
268 */
269 vma = find_extend_vma(current->mm, bprm->p);
270 if (!vma)
271 return -EFAULT;
272
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273 /* Now, let's put argc (and argv, envp if appropriate) on the stack */
274 if (__put_user(argc, sp++))
275 return -EFAULT;
Andi Kleend20894a2008-02-08 04:21:54 -0800276 argv = sp;
277 envp = argv + argc + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278
279 /* Populate argv and envp */
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -0700280 p = current->mm->arg_end = current->mm->arg_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 while (argc-- > 0) {
282 size_t len;
Heiko Carstens841d5fb2006-12-06 20:36:35 -0800283 if (__put_user((elf_addr_t)p, argv++))
284 return -EFAULT;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700285 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
286 if (!len || len > MAX_ARG_STRLEN)
WANG Cong23c49712008-05-08 21:52:33 +0800287 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 p += len;
289 }
290 if (__put_user(0, argv))
291 return -EFAULT;
292 current->mm->arg_end = current->mm->env_start = p;
293 while (envc-- > 0) {
294 size_t len;
Heiko Carstens841d5fb2006-12-06 20:36:35 -0800295 if (__put_user((elf_addr_t)p, envp++))
296 return -EFAULT;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700297 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
298 if (!len || len > MAX_ARG_STRLEN)
WANG Cong23c49712008-05-08 21:52:33 +0800299 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300 p += len;
301 }
302 if (__put_user(0, envp))
303 return -EFAULT;
304 current->mm->env_end = p;
305
306 /* Put the elf_info on the stack in the right place. */
307 sp = (elf_addr_t __user *)envp + 1;
308 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
309 return -EFAULT;
310 return 0;
311}
312
313#ifndef elf_map
314
315static unsigned long elf_map(struct file *filep, unsigned long addr,
Jiri Kosinacc503c12008-01-30 13:31:07 +0100316 struct elf_phdr *eppnt, int prot, int type,
317 unsigned long total_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318{
319 unsigned long map_addr;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100320 unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
321 unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
322 addr = ELF_PAGESTART(addr);
323 size = ELF_PAGEALIGN(size);
Jan Kratochvil60bfba72007-07-15 23:40:06 -0700324
Andrew Mortond4e3cc32007-07-21 04:37:32 -0700325 /* mmap() will return -EINVAL if given a zero size, but a
326 * segment with zero filesize is perfectly valid */
Jiri Kosinacc503c12008-01-30 13:31:07 +0100327 if (!size)
328 return addr;
329
330 down_write(&current->mm->mmap_sem);
331 /*
332 * total_size is the size of the ELF (interpreter) image.
333 * The _first_ mmap needs to know the full size, otherwise
334 * randomization might put this image into an overlapping
335 * position with the ELF binary image. (since size < total_size)
336 * So we first map the 'big' image - and unmap the remainder at
337 * the end. (which unmap is needed for ELF images with holes.)
338 */
339 if (total_size) {
340 total_size = ELF_PAGEALIGN(total_size);
341 map_addr = do_mmap(filep, addr, total_size, prot, type, off);
342 if (!BAD_ADDR(map_addr))
343 do_munmap(current->mm, map_addr+size, total_size-size);
344 } else
345 map_addr = do_mmap(filep, addr, size, prot, type, off);
346
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347 up_write(&current->mm->mmap_sem);
348 return(map_addr);
349}
350
351#endif /* !elf_map */
352
Jiri Kosinacc503c12008-01-30 13:31:07 +0100353static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr)
354{
355 int i, first_idx = -1, last_idx = -1;
356
357 for (i = 0; i < nr; i++) {
358 if (cmds[i].p_type == PT_LOAD) {
359 last_idx = i;
360 if (first_idx == -1)
361 first_idx = i;
362 }
363 }
364 if (first_idx == -1)
365 return 0;
366
367 return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz -
368 ELF_PAGESTART(cmds[first_idx].p_vaddr);
369}
370
371
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372/* This is much more generalized than the library routine read function,
373 so we keep this separate. Technically the library read function
374 is only provided so that we can read a.out libraries that have
375 an ELF header */
376
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700377static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
Jiri Kosinacc503c12008-01-30 13:31:07 +0100378 struct file *interpreter, unsigned long *interp_map_addr,
379 unsigned long no_base)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380{
381 struct elf_phdr *elf_phdata;
382 struct elf_phdr *eppnt;
383 unsigned long load_addr = 0;
384 int load_addr_set = 0;
385 unsigned long last_bss = 0, elf_bss = 0;
386 unsigned long error = ~0UL;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100387 unsigned long total_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 int retval, i, size;
389
390 /* First of all, some simple consistency checks */
391 if (interp_elf_ex->e_type != ET_EXEC &&
392 interp_elf_ex->e_type != ET_DYN)
393 goto out;
394 if (!elf_check_arch(interp_elf_ex))
395 goto out;
396 if (!interpreter->f_op || !interpreter->f_op->mmap)
397 goto out;
398
399 /*
400 * If the size of this structure has changed, then punt, since
401 * we will be doing the wrong thing.
402 */
403 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
404 goto out;
405 if (interp_elf_ex->e_phnum < 1 ||
406 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
407 goto out;
408
409 /* Now read in all of the header information */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
411 if (size > ELF_MIN_ALIGN)
412 goto out;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700413 elf_phdata = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414 if (!elf_phdata)
415 goto out;
416
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700417 retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
418 (char *)elf_phdata,size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 error = -EIO;
420 if (retval != size) {
421 if (retval < 0)
422 error = retval;
423 goto out_close;
424 }
425
Jiri Kosinacc503c12008-01-30 13:31:07 +0100426 total_size = total_mapping_size(elf_phdata, interp_elf_ex->e_phnum);
427 if (!total_size) {
428 error = -EINVAL;
429 goto out_close;
430 }
431
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432 eppnt = elf_phdata;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700433 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
434 if (eppnt->p_type == PT_LOAD) {
435 int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
436 int elf_prot = 0;
437 unsigned long vaddr = 0;
438 unsigned long k, map_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700440 if (eppnt->p_flags & PF_R)
441 elf_prot = PROT_READ;
442 if (eppnt->p_flags & PF_W)
443 elf_prot |= PROT_WRITE;
444 if (eppnt->p_flags & PF_X)
445 elf_prot |= PROT_EXEC;
446 vaddr = eppnt->p_vaddr;
447 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
448 elf_type |= MAP_FIXED;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100449 else if (no_base && interp_elf_ex->e_type == ET_DYN)
450 load_addr = -vaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700452 map_addr = elf_map(interpreter, load_addr + vaddr,
Andrew Mortonbb1ad822008-01-30 13:31:07 +0100453 eppnt, elf_prot, elf_type, total_size);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100454 total_size = 0;
455 if (!*interp_map_addr)
456 *interp_map_addr = map_addr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700457 error = map_addr;
458 if (BAD_ADDR(map_addr))
459 goto out_close;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700461 if (!load_addr_set &&
462 interp_elf_ex->e_type == ET_DYN) {
463 load_addr = map_addr - ELF_PAGESTART(vaddr);
464 load_addr_set = 1;
465 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700467 /*
468 * Check to see if the section's size will overflow the
469 * allowed task size. Note that p_filesz must always be
470 * <= p_memsize so it's only necessary to check p_memsz.
471 */
472 k = load_addr + eppnt->p_vaddr;
Chuck Ebbertce510592006-07-03 00:24:14 -0700473 if (BAD_ADDR(k) ||
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700474 eppnt->p_filesz > eppnt->p_memsz ||
475 eppnt->p_memsz > TASK_SIZE ||
476 TASK_SIZE - eppnt->p_memsz < k) {
477 error = -ENOMEM;
478 goto out_close;
479 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700481 /*
482 * Find the end of the file mapping for this phdr, and
483 * keep track of the largest address we see for this.
484 */
485 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
486 if (k > elf_bss)
487 elf_bss = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700489 /*
490 * Do the same thing for the memory mapping - between
491 * elf_bss and last_bss is the bss section.
492 */
493 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
494 if (k > last_bss)
495 last_bss = k;
496 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 }
498
499 /*
500 * Now fill out the bss section. First pad the last page up
501 * to the page boundary, and then perform a mmap to make sure
502 * that there are zero-mapped pages up to and including the
503 * last bss page.
504 */
505 if (padzero(elf_bss)) {
506 error = -EFAULT;
507 goto out_close;
508 }
509
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700510 /* What we have mapped so far */
511 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512
513 /* Map the last of the bss segment */
514 if (last_bss > elf_bss) {
515 down_write(&current->mm->mmap_sem);
516 error = do_brk(elf_bss, last_bss - elf_bss);
517 up_write(&current->mm->mmap_sem);
518 if (BAD_ADDR(error))
519 goto out_close;
520 }
521
Jiri Kosinacc503c12008-01-30 13:31:07 +0100522 error = load_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523
524out_close:
525 kfree(elf_phdata);
526out:
527 return error;
528}
529
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530/*
531 * These are the functions used to load ELF style executables and shared
532 * libraries. There is no binary dependent code anywhere else.
533 */
534
535#define INTERPRETER_NONE 0
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536#define INTERPRETER_ELF 2
537
Andi Kleen913bd902006-03-25 16:29:09 +0100538#ifndef STACK_RND_MASK
James Bottomleyd1cabd62007-03-16 13:38:35 -0800539#define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
Andi Kleen913bd902006-03-25 16:29:09 +0100540#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541
542static unsigned long randomize_stack_top(unsigned long stack_top)
543{
544 unsigned int random_variable = 0;
545
Andi Kleenc16b63e02006-09-26 10:52:28 +0200546 if ((current->flags & PF_RANDOMIZE) &&
547 !(current->personality & ADDR_NO_RANDOMIZE)) {
Andi Kleen913bd902006-03-25 16:29:09 +0100548 random_variable = get_random_int() & STACK_RND_MASK;
549 random_variable <<= PAGE_SHIFT;
550 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551#ifdef CONFIG_STACK_GROWSUP
Andi Kleen913bd902006-03-25 16:29:09 +0100552 return PAGE_ALIGN(stack_top) + random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553#else
Andi Kleen913bd902006-03-25 16:29:09 +0100554 return PAGE_ALIGN(stack_top) - random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555#endif
556}
557
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700558static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559{
560 struct file *interpreter = NULL; /* to shut gcc up */
561 unsigned long load_addr = 0, load_bias = 0;
562 int load_addr_set = 0;
563 char * elf_interpreter = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564 unsigned long error;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700565 struct elf_phdr *elf_ppnt, *elf_phdata;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566 unsigned long elf_bss, elf_brk;
567 int elf_exec_fileno;
568 int retval, i;
569 unsigned int size;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100570 unsigned long elf_entry;
571 unsigned long interp_load_addr = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 unsigned long start_code, end_code, start_data, end_data;
573 unsigned long reloc_func_desc = 0;
David Rientjes8de61e62006-12-06 20:40:16 -0800574 int executable_stack = EXSTACK_DEFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 unsigned long def_flags = 0;
576 struct {
577 struct elfhdr elf_ex;
578 struct elfhdr interp_elf_ex;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579 } *loc;
580
581 loc = kmalloc(sizeof(*loc), GFP_KERNEL);
582 if (!loc) {
583 retval = -ENOMEM;
584 goto out_ret;
585 }
586
587 /* Get the exec-header */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700588 loc->elf_ex = *((struct elfhdr *)bprm->buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589
590 retval = -ENOEXEC;
591 /* First of all, some simple consistency checks */
592 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
593 goto out;
594
595 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
596 goto out;
597 if (!elf_check_arch(&loc->elf_ex))
598 goto out;
599 if (!bprm->file->f_op||!bprm->file->f_op->mmap)
600 goto out;
601
602 /* Now read in all of the header information */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr))
604 goto out;
605 if (loc->elf_ex.e_phnum < 1 ||
606 loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr))
607 goto out;
608 size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr);
609 retval = -ENOMEM;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700610 elf_phdata = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 if (!elf_phdata)
612 goto out;
613
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700614 retval = kernel_read(bprm->file, loc->elf_ex.e_phoff,
615 (char *)elf_phdata, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616 if (retval != size) {
617 if (retval >= 0)
618 retval = -EIO;
619 goto out_free_ph;
620 }
621
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 retval = get_unused_fd();
623 if (retval < 0)
Al Virofd8328b2008-04-22 05:11:59 -0400624 goto out_free_ph;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 get_file(bprm->file);
626 fd_install(elf_exec_fileno = retval, bprm->file);
627
628 elf_ppnt = elf_phdata;
629 elf_bss = 0;
630 elf_brk = 0;
631
632 start_code = ~0UL;
633 end_code = 0;
634 start_data = 0;
635 end_data = 0;
636
637 for (i = 0; i < loc->elf_ex.e_phnum; i++) {
638 if (elf_ppnt->p_type == PT_INTERP) {
639 /* This is the program interpreter used for
640 * shared libraries - for now assume that this
641 * is an a.out format binary
642 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 retval = -ENOEXEC;
644 if (elf_ppnt->p_filesz > PATH_MAX ||
645 elf_ppnt->p_filesz < 2)
646 goto out_free_file;
647
648 retval = -ENOMEM;
Jesper Juhl792db3a2006-01-09 20:54:45 -0800649 elf_interpreter = kmalloc(elf_ppnt->p_filesz,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700650 GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 if (!elf_interpreter)
652 goto out_free_file;
653
654 retval = kernel_read(bprm->file, elf_ppnt->p_offset,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700655 elf_interpreter,
656 elf_ppnt->p_filesz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 if (retval != elf_ppnt->p_filesz) {
658 if (retval >= 0)
659 retval = -EIO;
660 goto out_free_interp;
661 }
662 /* make sure path is NULL terminated */
663 retval = -ENOEXEC;
664 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
665 goto out_free_interp;
666
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 /*
668 * The early SET_PERSONALITY here is so that the lookup
669 * for the interpreter happens in the namespace of the
670 * to-be-execed image. SET_PERSONALITY can select an
671 * alternate root.
672 *
673 * However, SET_PERSONALITY is NOT allowed to switch
674 * this task into the new images's memory mapping
675 * policy - that is, TASK_SIZE must still evaluate to
676 * that which is appropriate to the execing application.
677 * This is because exit_mmap() needs to have TASK_SIZE
678 * evaluate to the size of the old image.
679 *
680 * So if (say) a 64-bit application is execing a 32-bit
681 * application it is the architecture's responsibility
682 * to defer changing the value of TASK_SIZE until the
683 * switch really is going to happen - do this in
684 * flush_thread(). - akpm
685 */
Martin Schwidefsky0b592682008-10-16 15:39:57 +0200686 SET_PERSONALITY(loc->elf_ex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687
688 interpreter = open_exec(elf_interpreter);
689 retval = PTR_ERR(interpreter);
690 if (IS_ERR(interpreter))
691 goto out_free_interp;
Alexey Dobriyan1fb84492007-01-26 00:57:16 -0800692
693 /*
694 * If the binary is not readable then enforce
695 * mm->dumpable = 0 regardless of the interpreter's
696 * permissions.
697 */
698 if (file_permission(interpreter, MAY_READ) < 0)
699 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
700
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700701 retval = kernel_read(interpreter, 0, bprm->buf,
702 BINPRM_BUF_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 if (retval != BINPRM_BUF_SIZE) {
704 if (retval >= 0)
705 retval = -EIO;
706 goto out_free_dentry;
707 }
708
709 /* Get the exec headers */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700710 loc->interp_elf_ex = *((struct elfhdr *)bprm->buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 break;
712 }
713 elf_ppnt++;
714 }
715
716 elf_ppnt = elf_phdata;
717 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
718 if (elf_ppnt->p_type == PT_GNU_STACK) {
719 if (elf_ppnt->p_flags & PF_X)
720 executable_stack = EXSTACK_ENABLE_X;
721 else
722 executable_stack = EXSTACK_DISABLE_X;
723 break;
724 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725
726 /* Some simple consistency checks for the interpreter */
727 if (elf_interpreter) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 retval = -ELIBBAD;
Andi Kleend20894a2008-02-08 04:21:54 -0800729 /* Not an ELF interpreter */
730 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 goto out_free_dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732 /* Verify the interpreter has a valid arch */
Andi Kleend20894a2008-02-08 04:21:54 -0800733 if (!elf_check_arch(&loc->interp_elf_ex))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 goto out_free_dentry;
735 } else {
736 /* Executables without an interpreter also need a personality */
Martin Schwidefsky0b592682008-10-16 15:39:57 +0200737 SET_PERSONALITY(loc->elf_ex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 }
739
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740 /* Flush all traces of the currently running executable */
741 retval = flush_old_exec(bprm);
742 if (retval)
743 goto out_free_dentry;
744
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745 /* OK, This is the point of no return */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746 current->flags &= ~PF_FORKNOEXEC;
747 current->mm->def_flags = def_flags;
748
749 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
750 may depend on the personality. */
Martin Schwidefsky0b592682008-10-16 15:39:57 +0200751 SET_PERSONALITY(loc->elf_ex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 if (elf_read_implies_exec(loc->elf_ex, executable_stack))
753 current->personality |= READ_IMPLIES_EXEC;
754
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700755 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756 current->flags |= PF_RANDOMIZE;
757 arch_pick_mmap_layout(current->mm);
758
759 /* Do this so that we can load the interpreter, if need be. We will
760 change some of these later */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 current->mm->free_area_cache = current->mm->mmap_base;
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700762 current->mm->cached_hole_size = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
764 executable_stack);
765 if (retval < 0) {
766 send_sig(SIGKILL, current, 0);
767 goto out_free_dentry;
768 }
769
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770 current->mm->start_stack = bprm->p;
771
772 /* Now we do a little grungy work by mmaping the ELF image into
Jiri Kosinacc503c12008-01-30 13:31:07 +0100773 the correct location in memory. */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700774 for(i = 0, elf_ppnt = elf_phdata;
775 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 int elf_prot = 0, elf_flags;
777 unsigned long k, vaddr;
778
779 if (elf_ppnt->p_type != PT_LOAD)
780 continue;
781
782 if (unlikely (elf_brk > elf_bss)) {
783 unsigned long nbyte;
784
785 /* There was a PT_LOAD segment with p_memsz > p_filesz
786 before this one. Map anonymous pages, if needed,
787 and clear the area. */
788 retval = set_brk (elf_bss + load_bias,
789 elf_brk + load_bias);
790 if (retval) {
791 send_sig(SIGKILL, current, 0);
792 goto out_free_dentry;
793 }
794 nbyte = ELF_PAGEOFFSET(elf_bss);
795 if (nbyte) {
796 nbyte = ELF_MIN_ALIGN - nbyte;
797 if (nbyte > elf_brk - elf_bss)
798 nbyte = elf_brk - elf_bss;
799 if (clear_user((void __user *)elf_bss +
800 load_bias, nbyte)) {
801 /*
802 * This bss-zeroing can fail if the ELF
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700803 * file specifies odd protections. So
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804 * we don't check the return value
805 */
806 }
807 }
808 }
809
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700810 if (elf_ppnt->p_flags & PF_R)
811 elf_prot |= PROT_READ;
812 if (elf_ppnt->p_flags & PF_W)
813 elf_prot |= PROT_WRITE;
814 if (elf_ppnt->p_flags & PF_X)
815 elf_prot |= PROT_EXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700817 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818
819 vaddr = elf_ppnt->p_vaddr;
820 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
821 elf_flags |= MAP_FIXED;
822 } else if (loc->elf_ex.e_type == ET_DYN) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700823 /* Try and get dynamic programs out of the way of the
824 * default mmap base, as well as whatever program they
825 * might try to exec. This is because the brk will
826 * follow the loader, and is not movable. */
Jiri Kosinacc503c12008-01-30 13:31:07 +0100827#ifdef CONFIG_X86
828 load_bias = 0;
829#else
Linus Torvalds90cb28e2007-01-06 13:28:21 -0800830 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100831#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832 }
833
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700834 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
Andrew Mortonbb1ad822008-01-30 13:31:07 +0100835 elf_prot, elf_flags, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836 if (BAD_ADDR(error)) {
837 send_sig(SIGKILL, current, 0);
Alexey Kuznetsovb140f2512007-05-08 00:31:57 -0700838 retval = IS_ERR((void *)error) ?
839 PTR_ERR((void*)error) : -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840 goto out_free_dentry;
841 }
842
843 if (!load_addr_set) {
844 load_addr_set = 1;
845 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
846 if (loc->elf_ex.e_type == ET_DYN) {
847 load_bias += error -
848 ELF_PAGESTART(load_bias + vaddr);
849 load_addr += load_bias;
850 reloc_func_desc = load_bias;
851 }
852 }
853 k = elf_ppnt->p_vaddr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700854 if (k < start_code)
855 start_code = k;
856 if (start_data < k)
857 start_data = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858
859 /*
860 * Check to see if the section's size will overflow the
861 * allowed task size. Note that p_filesz must always be
862 * <= p_memsz so it is only necessary to check p_memsz.
863 */
Chuck Ebbertce510592006-07-03 00:24:14 -0700864 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865 elf_ppnt->p_memsz > TASK_SIZE ||
866 TASK_SIZE - elf_ppnt->p_memsz < k) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700867 /* set_brk can never work. Avoid overflows. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 send_sig(SIGKILL, current, 0);
Alexey Kuznetsovb140f2512007-05-08 00:31:57 -0700869 retval = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 goto out_free_dentry;
871 }
872
873 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
874
875 if (k > elf_bss)
876 elf_bss = k;
877 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
878 end_code = k;
879 if (end_data < k)
880 end_data = k;
881 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
882 if (k > elf_brk)
883 elf_brk = k;
884 }
885
886 loc->elf_ex.e_entry += load_bias;
887 elf_bss += load_bias;
888 elf_brk += load_bias;
889 start_code += load_bias;
890 end_code += load_bias;
891 start_data += load_bias;
892 end_data += load_bias;
893
894 /* Calling set_brk effectively mmaps the pages that we need
895 * for the bss and break sections. We must do this before
896 * mapping in the interpreter, to make sure it doesn't wind
897 * up getting placed where the bss needs to go.
898 */
899 retval = set_brk(elf_bss, elf_brk);
900 if (retval) {
901 send_sig(SIGKILL, current, 0);
902 goto out_free_dentry;
903 }
akpm@osdl.org6de50512005-10-11 08:29:08 -0700904 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905 send_sig(SIGSEGV, current, 0);
906 retval = -EFAULT; /* Nobody gets to see this, but.. */
907 goto out_free_dentry;
908 }
909
910 if (elf_interpreter) {
Andi Kleend20894a2008-02-08 04:21:54 -0800911 unsigned long uninitialized_var(interp_map_addr);
Jiri Kosinacc503c12008-01-30 13:31:07 +0100912
Andi Kleend20894a2008-02-08 04:21:54 -0800913 elf_entry = load_elf_interp(&loc->interp_elf_ex,
914 interpreter,
915 &interp_map_addr,
916 load_bias);
917 if (!IS_ERR((void *)elf_entry)) {
918 /*
919 * load_elf_interp() returns relocation
920 * adjustment
921 */
922 interp_load_addr = elf_entry;
923 elf_entry += loc->interp_elf_ex.e_entry;
Jiri Kosinacc503c12008-01-30 13:31:07 +0100924 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925 if (BAD_ADDR(elf_entry)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926 force_sig(SIGSEGV, current);
Chuck Ebbertce510592006-07-03 00:24:14 -0700927 retval = IS_ERR((void *)elf_entry) ?
928 (int)elf_entry : -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700929 goto out_free_dentry;
930 }
931 reloc_func_desc = interp_load_addr;
932
933 allow_write_access(interpreter);
934 fput(interpreter);
935 kfree(elf_interpreter);
936 } else {
937 elf_entry = loc->elf_ex.e_entry;
Suresh Siddha5342fba2006-02-26 04:18:28 +0100938 if (BAD_ADDR(elf_entry)) {
Chuck Ebbertce510592006-07-03 00:24:14 -0700939 force_sig(SIGSEGV, current);
940 retval = -EINVAL;
Suresh Siddha5342fba2006-02-26 04:18:28 +0100941 goto out_free_dentry;
942 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943 }
944
945 kfree(elf_phdata);
946
Andi Kleend20894a2008-02-08 04:21:54 -0800947 sys_close(elf_exec_fileno);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948
949 set_binfmt(&elf_format);
950
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -0700951#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
952 retval = arch_setup_additional_pages(bprm, executable_stack);
953 if (retval < 0) {
954 send_sig(SIGKILL, current, 0);
Roland McGrath18c8baf2005-04-28 15:17:19 -0700955 goto out;
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -0700956 }
957#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
958
Linus Torvalds1da177e2005-04-16 15:20:36 -0700959 compute_creds(bprm);
960 current->flags &= ~PF_FORKNOEXEC;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700961 retval = create_elf_tables(bprm, &loc->elf_ex,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700962 load_addr, interp_load_addr);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700963 if (retval < 0) {
964 send_sig(SIGKILL, current, 0);
965 goto out;
966 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967 /* N.B. passed_fileno might not be initialized? */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968 current->mm->end_code = end_code;
969 current->mm->start_code = start_code;
970 current->mm->start_data = start_data;
971 current->mm->end_data = end_data;
972 current->mm->start_stack = bprm->p;
973
Jiri Kosinac1d171a2008-01-30 13:30:40 +0100974#ifdef arch_randomize_brk
Ingo Molnar32a93232008-02-06 22:39:44 +0100975 if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1))
Jiri Kosinac1d171a2008-01-30 13:30:40 +0100976 current->mm->brk = current->mm->start_brk =
977 arch_randomize_brk(current->mm);
978#endif
979
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 if (current->personality & MMAP_PAGE_ZERO) {
981 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
982 and some applications "depend" upon this behavior.
983 Since we do not have the power to recompile these, we
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700984 emulate the SVr4 behavior. Sigh. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985 down_write(&current->mm->mmap_sem);
986 error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
987 MAP_FIXED | MAP_PRIVATE, 0);
988 up_write(&current->mm->mmap_sem);
989 }
990
991#ifdef ELF_PLAT_INIT
992 /*
993 * The ABI may specify that certain registers be set up in special
994 * ways (on i386 %edx is the address of a DT_FINI function, for
995 * example. In addition, it may also specify (eg, PowerPC64 ELF)
996 * that the e_entry field is the address of the function descriptor
997 * for the startup routine, rather than the address of the startup
998 * routine itself. This macro performs whatever initialization to
999 * the regs structure is required as well as any relocations to the
1000 * function descriptor entries when executing dynamically links apps.
1001 */
1002 ELF_PLAT_INIT(regs, reloc_func_desc);
1003#endif
1004
1005 start_thread(regs, elf_entry, bprm->p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 retval = 0;
1007out:
1008 kfree(loc);
1009out_ret:
1010 return retval;
1011
1012 /* error cleanup */
1013out_free_dentry:
1014 allow_write_access(interpreter);
1015 if (interpreter)
1016 fput(interpreter);
1017out_free_interp:
Jesper Juhlf99d49a2005-11-07 01:01:34 -08001018 kfree(elf_interpreter);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019out_free_file:
1020 sys_close(elf_exec_fileno);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001021out_free_ph:
1022 kfree(elf_phdata);
1023 goto out;
1024}
1025
1026/* This is really simpleminded and specialized - we are loading an
1027 a.out library that is given an ELF header. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028static int load_elf_library(struct file *file)
1029{
1030 struct elf_phdr *elf_phdata;
1031 struct elf_phdr *eppnt;
1032 unsigned long elf_bss, bss, len;
1033 int retval, error, i, j;
1034 struct elfhdr elf_ex;
1035
1036 error = -ENOEXEC;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001037 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001038 if (retval != sizeof(elf_ex))
1039 goto out;
1040
1041 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
1042 goto out;
1043
1044 /* First of all, some simple consistency checks */
1045 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001046 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001047 goto out;
1048
1049 /* Now read in all of the header information */
1050
1051 j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
1052 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1053
1054 error = -ENOMEM;
1055 elf_phdata = kmalloc(j, GFP_KERNEL);
1056 if (!elf_phdata)
1057 goto out;
1058
1059 eppnt = elf_phdata;
1060 error = -ENOEXEC;
1061 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
1062 if (retval != j)
1063 goto out_free_ph;
1064
1065 for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
1066 if ((eppnt + i)->p_type == PT_LOAD)
1067 j++;
1068 if (j != 1)
1069 goto out_free_ph;
1070
1071 while (eppnt->p_type != PT_LOAD)
1072 eppnt++;
1073
1074 /* Now use mmap to map the library into memory. */
1075 down_write(&current->mm->mmap_sem);
1076 error = do_mmap(file,
1077 ELF_PAGESTART(eppnt->p_vaddr),
1078 (eppnt->p_filesz +
1079 ELF_PAGEOFFSET(eppnt->p_vaddr)),
1080 PROT_READ | PROT_WRITE | PROT_EXEC,
1081 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
1082 (eppnt->p_offset -
1083 ELF_PAGEOFFSET(eppnt->p_vaddr)));
1084 up_write(&current->mm->mmap_sem);
1085 if (error != ELF_PAGESTART(eppnt->p_vaddr))
1086 goto out_free_ph;
1087
1088 elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
1089 if (padzero(elf_bss)) {
1090 error = -EFAULT;
1091 goto out_free_ph;
1092 }
1093
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001094 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
1095 ELF_MIN_ALIGN - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096 bss = eppnt->p_memsz + eppnt->p_vaddr;
1097 if (bss > len) {
1098 down_write(&current->mm->mmap_sem);
1099 do_brk(len, bss - len);
1100 up_write(&current->mm->mmap_sem);
1101 }
1102 error = 0;
1103
1104out_free_ph:
1105 kfree(elf_phdata);
1106out:
1107 return error;
1108}
1109
1110/*
1111 * Note that some platforms still use traditional core dumps and not
1112 * the ELF core dump. Each platform can select it as appropriate.
1113 */
Matt Mackall708e9a72006-01-08 01:05:25 -08001114#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001115
1116/*
1117 * ELF core dumper
1118 *
1119 * Modelled on fs/exec.c:aout_core_dump()
1120 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1121 */
1122/*
1123 * These are the only things you should do on a core-file: use only these
1124 * functions to write out all the necessary info.
1125 */
1126static int dump_write(struct file *file, const void *addr, int nr)
1127{
1128 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
1129}
1130
Daniel Jacobowitz5db92852005-06-15 22:26:34 -07001131static int dump_seek(struct file *file, loff_t off)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001132{
Andi Kleend025c9d2006-09-30 23:29:28 -07001133 if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
Petr Vandrovec7f14daa2006-10-13 04:13:16 +02001134 if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135 return 0;
Andi Kleend025c9d2006-09-30 23:29:28 -07001136 } else {
1137 char *buf = (char *)get_zeroed_page(GFP_KERNEL);
1138 if (!buf)
1139 return 0;
1140 while (off > 0) {
1141 unsigned long n = off;
1142 if (n > PAGE_SIZE)
1143 n = PAGE_SIZE;
1144 if (!dump_write(file, buf, n))
1145 return 0;
1146 off -= n;
1147 }
1148 free_page((unsigned long)buf);
1149 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150 return 1;
1151}
1152
1153/*
Roland McGrath82df3972007-10-16 23:27:02 -07001154 * Decide what to dump of a segment, part, all or none.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155 */
Roland McGrath82df3972007-10-16 23:27:02 -07001156static unsigned long vma_dump_size(struct vm_area_struct *vma,
1157 unsigned long mm_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158{
KOSAKI Motohiroe575f112008-10-18 20:27:08 -07001159#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1160
Roland McGrathe5b97dd2007-01-26 00:56:48 -08001161 /* The vma can be set up to tell us the answer directly. */
1162 if (vma->vm_flags & VM_ALWAYSDUMP)
Roland McGrath82df3972007-10-16 23:27:02 -07001163 goto whole;
Roland McGrathe5b97dd2007-01-26 00:56:48 -08001164
KOSAKI Motohiroe575f112008-10-18 20:27:08 -07001165 /* Hugetlb memory check */
1166 if (vma->vm_flags & VM_HUGETLB) {
1167 if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
1168 goto whole;
1169 if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
1170 goto whole;
1171 }
1172
Linus Torvalds1da177e2005-04-16 15:20:36 -07001173 /* Do not dump I/O mapped devices or special mappings */
1174 if (vma->vm_flags & (VM_IO | VM_RESERVED))
1175 return 0;
1176
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001177 /* By default, dump shared memory if mapped from an anonymous file. */
1178 if (vma->vm_flags & VM_SHARED) {
Roland McGrath82df3972007-10-16 23:27:02 -07001179 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ?
1180 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
1181 goto whole;
1182 return 0;
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001183 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001184
Roland McGrath82df3972007-10-16 23:27:02 -07001185 /* Dump segments that have been written to. */
1186 if (vma->anon_vma && FILTER(ANON_PRIVATE))
1187 goto whole;
1188 if (vma->vm_file == NULL)
1189 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001190
Roland McGrath82df3972007-10-16 23:27:02 -07001191 if (FILTER(MAPPED_PRIVATE))
1192 goto whole;
1193
1194 /*
1195 * If this looks like the beginning of a DSO or executable mapping,
1196 * check for an ELF header. If we find one, dump the first page to
1197 * aid in determining what was mapped here.
1198 */
1199 if (FILTER(ELF_HEADERS) && vma->vm_file != NULL && vma->vm_pgoff == 0) {
1200 u32 __user *header = (u32 __user *) vma->vm_start;
1201 u32 word;
1202 /*
1203 * Doing it this way gets the constant folded by GCC.
1204 */
1205 union {
1206 u32 cmp;
1207 char elfmag[SELFMAG];
1208 } magic;
1209 BUILD_BUG_ON(SELFMAG != sizeof word);
1210 magic.elfmag[EI_MAG0] = ELFMAG0;
1211 magic.elfmag[EI_MAG1] = ELFMAG1;
1212 magic.elfmag[EI_MAG2] = ELFMAG2;
1213 magic.elfmag[EI_MAG3] = ELFMAG3;
1214 if (get_user(word, header) == 0 && word == magic.cmp)
1215 return PAGE_SIZE;
1216 }
1217
1218#undef FILTER
1219
1220 return 0;
1221
1222whole:
1223 return vma->vm_end - vma->vm_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001224}
1225
Linus Torvalds1da177e2005-04-16 15:20:36 -07001226/* An ELF note in memory */
1227struct memelfnote
1228{
1229 const char *name;
1230 int type;
1231 unsigned int datasz;
1232 void *data;
1233};
1234
1235static int notesize(struct memelfnote *en)
1236{
1237 int sz;
1238
1239 sz = sizeof(struct elf_note);
1240 sz += roundup(strlen(en->name) + 1, 4);
1241 sz += roundup(en->datasz, 4);
1242
1243 return sz;
1244}
1245
Andi Kleend025c9d2006-09-30 23:29:28 -07001246#define DUMP_WRITE(addr, nr, foffset) \
1247 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001248
Andi Kleend025c9d2006-09-30 23:29:28 -07001249static int alignfile(struct file *file, loff_t *foffset)
1250{
Petr Vandroveca7a0d862006-10-13 18:42:07 +02001251 static const char buf[4] = { 0, };
Andi Kleend025c9d2006-09-30 23:29:28 -07001252 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
1253 return 1;
1254}
1255
1256static int writenote(struct memelfnote *men, struct file *file,
1257 loff_t *foffset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258{
1259 struct elf_note en;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001260 en.n_namesz = strlen(men->name) + 1;
1261 en.n_descsz = men->datasz;
1262 en.n_type = men->type;
1263
Andi Kleend025c9d2006-09-30 23:29:28 -07001264 DUMP_WRITE(&en, sizeof(en), foffset);
1265 DUMP_WRITE(men->name, en.n_namesz, foffset);
1266 if (!alignfile(file, foffset))
1267 return 0;
1268 DUMP_WRITE(men->data, men->datasz, foffset);
1269 if (!alignfile(file, foffset))
1270 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001271
1272 return 1;
1273}
1274#undef DUMP_WRITE
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275
1276#define DUMP_WRITE(addr, nr) \
1277 if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
1278 goto end_coredump;
1279#define DUMP_SEEK(off) \
1280 if (!dump_seek(file, (off))) \
1281 goto end_coredump;
1282
Roland McGrath3aba4812008-01-30 13:31:44 +01001283static void fill_elf_header(struct elfhdr *elf, int segs,
1284 u16 machine, u32 flags, u8 osabi)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001285{
Cyrill Gorcunov6970c8e2008-04-29 01:01:18 -07001286 memset(elf, 0, sizeof(*elf));
1287
Linus Torvalds1da177e2005-04-16 15:20:36 -07001288 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1289 elf->e_ident[EI_CLASS] = ELF_CLASS;
1290 elf->e_ident[EI_DATA] = ELF_DATA;
1291 elf->e_ident[EI_VERSION] = EV_CURRENT;
1292 elf->e_ident[EI_OSABI] = ELF_OSABI;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001293
1294 elf->e_type = ET_CORE;
Roland McGrath3aba4812008-01-30 13:31:44 +01001295 elf->e_machine = machine;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296 elf->e_version = EV_CURRENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001297 elf->e_phoff = sizeof(struct elfhdr);
Roland McGrath3aba4812008-01-30 13:31:44 +01001298 elf->e_flags = flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299 elf->e_ehsize = sizeof(struct elfhdr);
1300 elf->e_phentsize = sizeof(struct elf_phdr);
1301 elf->e_phnum = segs;
Cyrill Gorcunov6970c8e2008-04-29 01:01:18 -07001302
Linus Torvalds1da177e2005-04-16 15:20:36 -07001303 return;
1304}
1305
Andrew Morton8d6b5eee2006-09-25 23:32:04 -07001306static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001307{
1308 phdr->p_type = PT_NOTE;
1309 phdr->p_offset = offset;
1310 phdr->p_vaddr = 0;
1311 phdr->p_paddr = 0;
1312 phdr->p_filesz = sz;
1313 phdr->p_memsz = 0;
1314 phdr->p_flags = 0;
1315 phdr->p_align = 0;
1316 return;
1317}
1318
1319static void fill_note(struct memelfnote *note, const char *name, int type,
1320 unsigned int sz, void *data)
1321{
1322 note->name = name;
1323 note->type = type;
1324 note->datasz = sz;
1325 note->data = data;
1326 return;
1327}
1328
1329/*
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001330 * fill up all the fields in prstatus from the given task struct, except
1331 * registers which need to be filled up separately.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001332 */
1333static void fill_prstatus(struct elf_prstatus *prstatus,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001334 struct task_struct *p, long signr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001335{
1336 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1337 prstatus->pr_sigpend = p->pending.signal.sig[0];
1338 prstatus->pr_sighold = p->blocked.sig[0];
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001339 prstatus->pr_pid = task_pid_vnr(p);
Roland McGrath45626bb2008-01-07 14:22:44 -08001340 prstatus->pr_ppid = task_pid_vnr(p->real_parent);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001341 prstatus->pr_pgrp = task_pgrp_vnr(p);
1342 prstatus->pr_sid = task_session_vnr(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001343 if (thread_group_leader(p)) {
Frank Mayharf06febc2008-09-12 09:54:39 -07001344 struct task_cputime cputime;
1345
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346 /*
Frank Mayharf06febc2008-09-12 09:54:39 -07001347 * This is the record for the group leader. It shows the
1348 * group-wide total, not its individual thread total.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001349 */
Frank Mayharf06febc2008-09-12 09:54:39 -07001350 thread_group_cputime(p, &cputime);
1351 cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
1352 cputime_to_timeval(cputime.stime, &prstatus->pr_stime);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001353 } else {
1354 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1355 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1356 }
1357 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1358 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1359}
1360
1361static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1362 struct mm_struct *mm)
1363{
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -07001364 unsigned int i, len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001365
1366 /* first copy the parameters from user space */
1367 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1368
1369 len = mm->arg_end - mm->arg_start;
1370 if (len >= ELF_PRARGSZ)
1371 len = ELF_PRARGSZ-1;
1372 if (copy_from_user(&psinfo->pr_psargs,
1373 (const char __user *)mm->arg_start, len))
1374 return -EFAULT;
1375 for(i = 0; i < len; i++)
1376 if (psinfo->pr_psargs[i] == 0)
1377 psinfo->pr_psargs[i] = ' ';
1378 psinfo->pr_psargs[len] = 0;
1379
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001380 psinfo->pr_pid = task_pid_vnr(p);
Roland McGrath45626bb2008-01-07 14:22:44 -08001381 psinfo->pr_ppid = task_pid_vnr(p->real_parent);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001382 psinfo->pr_pgrp = task_pgrp_vnr(p);
1383 psinfo->pr_sid = task_session_vnr(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001384
1385 i = p->state ? ffz(~p->state) + 1 : 0;
1386 psinfo->pr_state = i;
Carsten Otte55148542006-03-25 03:08:22 -08001387 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001388 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1389 psinfo->pr_nice = task_nice(p);
1390 psinfo->pr_flag = p->flags;
1391 SET_UID(psinfo->pr_uid, p->uid);
1392 SET_GID(psinfo->pr_gid, p->gid);
1393 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1394
1395 return 0;
1396}
1397
Roland McGrath3aba4812008-01-30 13:31:44 +01001398static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
1399{
1400 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
1401 int i = 0;
1402 do
1403 i += 2;
1404 while (auxv[i - 2] != AT_NULL);
1405 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
1406}
1407
Roland McGrath4206d3a2008-01-30 13:31:45 +01001408#ifdef CORE_DUMP_USE_REGSET
1409#include <linux/regset.h>
1410
1411struct elf_thread_core_info {
1412 struct elf_thread_core_info *next;
1413 struct task_struct *task;
1414 struct elf_prstatus prstatus;
1415 struct memelfnote notes[0];
1416};
1417
1418struct elf_note_info {
1419 struct elf_thread_core_info *thread;
1420 struct memelfnote psinfo;
1421 struct memelfnote auxv;
1422 size_t size;
1423 int thread_notes;
1424};
1425
Roland McGrathd31472b2008-03-04 14:28:30 -08001426/*
1427 * When a regset has a writeback hook, we call it on each thread before
1428 * dumping user memory. On register window machines, this makes sure the
1429 * user memory backing the register data is up to date before we read it.
1430 */
1431static void do_thread_regset_writeback(struct task_struct *task,
1432 const struct user_regset *regset)
1433{
1434 if (regset->writeback)
1435 regset->writeback(task, regset, 1);
1436}
1437
Roland McGrath4206d3a2008-01-30 13:31:45 +01001438static int fill_thread_core_info(struct elf_thread_core_info *t,
1439 const struct user_regset_view *view,
1440 long signr, size_t *total)
1441{
1442 unsigned int i;
1443
1444 /*
1445 * NT_PRSTATUS is the one special case, because the regset data
1446 * goes into the pr_reg field inside the note contents, rather
1447 * than being the whole note contents. We fill the reset in here.
1448 * We assume that regset 0 is NT_PRSTATUS.
1449 */
1450 fill_prstatus(&t->prstatus, t->task, signr);
1451 (void) view->regsets[0].get(t->task, &view->regsets[0],
1452 0, sizeof(t->prstatus.pr_reg),
1453 &t->prstatus.pr_reg, NULL);
1454
1455 fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
1456 sizeof(t->prstatus), &t->prstatus);
1457 *total += notesize(&t->notes[0]);
1458
Roland McGrathd31472b2008-03-04 14:28:30 -08001459 do_thread_regset_writeback(t->task, &view->regsets[0]);
1460
Roland McGrath4206d3a2008-01-30 13:31:45 +01001461 /*
1462 * Each other regset might generate a note too. For each regset
1463 * that has no core_note_type or is inactive, we leave t->notes[i]
1464 * all zero and we'll know to skip writing it later.
1465 */
1466 for (i = 1; i < view->n; ++i) {
1467 const struct user_regset *regset = &view->regsets[i];
Roland McGrathd31472b2008-03-04 14:28:30 -08001468 do_thread_regset_writeback(t->task, regset);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001469 if (regset->core_note_type &&
1470 (!regset->active || regset->active(t->task, regset))) {
1471 int ret;
1472 size_t size = regset->n * regset->size;
1473 void *data = kmalloc(size, GFP_KERNEL);
1474 if (unlikely(!data))
1475 return 0;
1476 ret = regset->get(t->task, regset,
1477 0, size, data, NULL);
1478 if (unlikely(ret))
1479 kfree(data);
1480 else {
1481 if (regset->core_note_type != NT_PRFPREG)
1482 fill_note(&t->notes[i], "LINUX",
1483 regset->core_note_type,
1484 size, data);
1485 else {
1486 t->prstatus.pr_fpvalid = 1;
1487 fill_note(&t->notes[i], "CORE",
1488 NT_PRFPREG, size, data);
1489 }
1490 *total += notesize(&t->notes[i]);
1491 }
1492 }
1493 }
1494
1495 return 1;
1496}
1497
1498static int fill_note_info(struct elfhdr *elf, int phdrs,
1499 struct elf_note_info *info,
1500 long signr, struct pt_regs *regs)
1501{
1502 struct task_struct *dump_task = current;
1503 const struct user_regset_view *view = task_user_regset_view(dump_task);
1504 struct elf_thread_core_info *t;
1505 struct elf_prpsinfo *psinfo;
Oleg Nesterov83914442008-07-25 01:47:45 -07001506 struct core_thread *ct;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001507 unsigned int i;
1508
1509 info->size = 0;
1510 info->thread = NULL;
1511
1512 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1513 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1514
1515 if (psinfo == NULL)
1516 return 0;
1517
1518 /*
1519 * Figure out how many notes we're going to need for each thread.
1520 */
1521 info->thread_notes = 0;
1522 for (i = 0; i < view->n; ++i)
1523 if (view->regsets[i].core_note_type != 0)
1524 ++info->thread_notes;
1525
1526 /*
1527 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1528 * since it is our one special case.
1529 */
1530 if (unlikely(info->thread_notes == 0) ||
1531 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
1532 WARN_ON(1);
1533 return 0;
1534 }
1535
1536 /*
1537 * Initialize the ELF file header.
1538 */
1539 fill_elf_header(elf, phdrs,
1540 view->e_machine, view->e_flags, view->ei_osabi);
1541
1542 /*
1543 * Allocate a structure for each thread.
1544 */
Oleg Nesterov83914442008-07-25 01:47:45 -07001545 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) {
1546 t = kzalloc(offsetof(struct elf_thread_core_info,
1547 notes[info->thread_notes]),
1548 GFP_KERNEL);
1549 if (unlikely(!t))
1550 return 0;
Oleg Nesterov24d52882008-07-25 01:47:40 -07001551
Oleg Nesterov83914442008-07-25 01:47:45 -07001552 t->task = ct->task;
1553 if (ct->task == dump_task || !info->thread) {
1554 t->next = info->thread;
1555 info->thread = t;
1556 } else {
1557 /*
1558 * Make sure to keep the original task at
1559 * the head of the list.
1560 */
1561 t->next = info->thread->next;
1562 info->thread->next = t;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001563 }
Oleg Nesterov83914442008-07-25 01:47:45 -07001564 }
Roland McGrath4206d3a2008-01-30 13:31:45 +01001565
1566 /*
1567 * Now fill in each thread's information.
1568 */
1569 for (t = info->thread; t != NULL; t = t->next)
1570 if (!fill_thread_core_info(t, view, signr, &info->size))
1571 return 0;
1572
1573 /*
1574 * Fill in the two process-wide notes.
1575 */
1576 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
1577 info->size += notesize(&info->psinfo);
1578
1579 fill_auxv_note(&info->auxv, current->mm);
1580 info->size += notesize(&info->auxv);
1581
1582 return 1;
1583}
1584
1585static size_t get_note_info_size(struct elf_note_info *info)
1586{
1587 return info->size;
1588}
1589
1590/*
1591 * Write all the notes for each thread. When writing the first thread, the
1592 * process-wide notes are interleaved after the first thread-specific note.
1593 */
1594static int write_note_info(struct elf_note_info *info,
1595 struct file *file, loff_t *foffset)
1596{
1597 bool first = 1;
1598 struct elf_thread_core_info *t = info->thread;
1599
1600 do {
1601 int i;
1602
1603 if (!writenote(&t->notes[0], file, foffset))
1604 return 0;
1605
1606 if (first && !writenote(&info->psinfo, file, foffset))
1607 return 0;
1608 if (first && !writenote(&info->auxv, file, foffset))
1609 return 0;
1610
1611 for (i = 1; i < info->thread_notes; ++i)
1612 if (t->notes[i].data &&
1613 !writenote(&t->notes[i], file, foffset))
1614 return 0;
1615
1616 first = 0;
1617 t = t->next;
1618 } while (t);
1619
1620 return 1;
1621}
1622
1623static void free_note_info(struct elf_note_info *info)
1624{
1625 struct elf_thread_core_info *threads = info->thread;
1626 while (threads) {
1627 unsigned int i;
1628 struct elf_thread_core_info *t = threads;
1629 threads = t->next;
1630 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
1631 for (i = 1; i < info->thread_notes; ++i)
1632 kfree(t->notes[i].data);
1633 kfree(t);
1634 }
1635 kfree(info->psinfo.data);
1636}
1637
1638#else
1639
Linus Torvalds1da177e2005-04-16 15:20:36 -07001640/* Here is the structure in which status of each thread is captured. */
1641struct elf_thread_status
1642{
1643 struct list_head list;
1644 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1645 elf_fpregset_t fpu; /* NT_PRFPREG */
1646 struct task_struct *thread;
1647#ifdef ELF_CORE_COPY_XFPREGS
Mark Nelson5b20cd82007-10-16 23:25:39 -07001648 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001649#endif
1650 struct memelfnote notes[3];
1651 int num_notes;
1652};
1653
1654/*
1655 * In order to add the specific thread information for the elf file format,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001656 * we need to keep a linked list of every threads pr_status and then create
1657 * a single section for them in the final core file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001658 */
1659static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1660{
1661 int sz = 0;
1662 struct task_struct *p = t->thread;
1663 t->num_notes = 0;
1664
1665 fill_prstatus(&t->prstatus, p, signr);
1666 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1667
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001668 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1669 &(t->prstatus));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001670 t->num_notes++;
1671 sz += notesize(&t->notes[0]);
1672
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001673 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1674 &t->fpu))) {
1675 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1676 &(t->fpu));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001677 t->num_notes++;
1678 sz += notesize(&t->notes[1]);
1679 }
1680
1681#ifdef ELF_CORE_COPY_XFPREGS
1682 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
Mark Nelson5b20cd82007-10-16 23:25:39 -07001683 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1684 sizeof(t->xfpu), &t->xfpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685 t->num_notes++;
1686 sz += notesize(&t->notes[2]);
1687 }
1688#endif
1689 return sz;
1690}
1691
Roland McGrath3aba4812008-01-30 13:31:44 +01001692struct elf_note_info {
1693 struct memelfnote *notes;
1694 struct elf_prstatus *prstatus; /* NT_PRSTATUS */
1695 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */
1696 struct list_head thread_list;
1697 elf_fpregset_t *fpu;
1698#ifdef ELF_CORE_COPY_XFPREGS
1699 elf_fpxregset_t *xfpu;
1700#endif
1701 int thread_status_size;
1702 int numnote;
1703};
1704
1705static int fill_note_info(struct elfhdr *elf, int phdrs,
1706 struct elf_note_info *info,
1707 long signr, struct pt_regs *regs)
1708{
1709#define NUM_NOTES 6
1710 struct list_head *t;
Roland McGrath3aba4812008-01-30 13:31:44 +01001711
1712 info->notes = NULL;
1713 info->prstatus = NULL;
1714 info->psinfo = NULL;
1715 info->fpu = NULL;
1716#ifdef ELF_CORE_COPY_XFPREGS
1717 info->xfpu = NULL;
1718#endif
1719 INIT_LIST_HEAD(&info->thread_list);
1720
1721 info->notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote),
1722 GFP_KERNEL);
1723 if (!info->notes)
1724 return 0;
1725 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
1726 if (!info->psinfo)
1727 return 0;
1728 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
1729 if (!info->prstatus)
1730 return 0;
1731 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
1732 if (!info->fpu)
1733 return 0;
1734#ifdef ELF_CORE_COPY_XFPREGS
1735 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
1736 if (!info->xfpu)
1737 return 0;
1738#endif
1739
1740 info->thread_status_size = 0;
1741 if (signr) {
Oleg Nesterov83914442008-07-25 01:47:45 -07001742 struct core_thread *ct;
WANG Cong4220b7f2008-04-29 01:01:18 -07001743 struct elf_thread_status *ets;
Oleg Nesterov24d52882008-07-25 01:47:40 -07001744
Oleg Nesterov83914442008-07-25 01:47:45 -07001745 for (ct = current->mm->core_state->dumper.next;
1746 ct; ct = ct->next) {
1747 ets = kzalloc(sizeof(*ets), GFP_KERNEL);
1748 if (!ets)
1749 return 0;
1750
1751 ets->thread = ct->task;
1752 list_add(&ets->list, &info->thread_list);
1753 }
1754
Roland McGrath3aba4812008-01-30 13:31:44 +01001755 list_for_each(t, &info->thread_list) {
Roland McGrath3aba4812008-01-30 13:31:44 +01001756 int sz;
1757
WANG Cong4220b7f2008-04-29 01:01:18 -07001758 ets = list_entry(t, struct elf_thread_status, list);
1759 sz = elf_dump_thread_status(signr, ets);
Roland McGrath3aba4812008-01-30 13:31:44 +01001760 info->thread_status_size += sz;
1761 }
1762 }
1763 /* now collect the dump for the current */
1764 memset(info->prstatus, 0, sizeof(*info->prstatus));
1765 fill_prstatus(info->prstatus, current, signr);
1766 elf_core_copy_regs(&info->prstatus->pr_reg, regs);
1767
1768 /* Set up header */
1769 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI);
1770
1771 /*
1772 * Set up the notes in similar form to SVR4 core dumps made
1773 * with info from their /proc.
1774 */
1775
1776 fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
1777 sizeof(*info->prstatus), info->prstatus);
1778 fill_psinfo(info->psinfo, current->group_leader, current->mm);
1779 fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
1780 sizeof(*info->psinfo), info->psinfo);
1781
1782 info->numnote = 2;
1783
1784 fill_auxv_note(&info->notes[info->numnote++], current->mm);
1785
1786 /* Try to dump the FPU. */
1787 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
1788 info->fpu);
1789 if (info->prstatus->pr_fpvalid)
1790 fill_note(info->notes + info->numnote++,
1791 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
1792#ifdef ELF_CORE_COPY_XFPREGS
1793 if (elf_core_copy_task_xfpregs(current, info->xfpu))
1794 fill_note(info->notes + info->numnote++,
1795 "LINUX", ELF_CORE_XFPREG_TYPE,
1796 sizeof(*info->xfpu), info->xfpu);
1797#endif
1798
1799 return 1;
1800
1801#undef NUM_NOTES
1802}
1803
1804static size_t get_note_info_size(struct elf_note_info *info)
1805{
1806 int sz = 0;
1807 int i;
1808
1809 for (i = 0; i < info->numnote; i++)
1810 sz += notesize(info->notes + i);
1811
1812 sz += info->thread_status_size;
1813
1814 return sz;
1815}
1816
1817static int write_note_info(struct elf_note_info *info,
1818 struct file *file, loff_t *foffset)
1819{
1820 int i;
1821 struct list_head *t;
1822
1823 for (i = 0; i < info->numnote; i++)
1824 if (!writenote(info->notes + i, file, foffset))
1825 return 0;
1826
1827 /* write out the thread status notes section */
1828 list_for_each(t, &info->thread_list) {
1829 struct elf_thread_status *tmp =
1830 list_entry(t, struct elf_thread_status, list);
1831
1832 for (i = 0; i < tmp->num_notes; i++)
1833 if (!writenote(&tmp->notes[i], file, foffset))
1834 return 0;
1835 }
1836
1837 return 1;
1838}
1839
1840static void free_note_info(struct elf_note_info *info)
1841{
1842 while (!list_empty(&info->thread_list)) {
1843 struct list_head *tmp = info->thread_list.next;
1844 list_del(tmp);
1845 kfree(list_entry(tmp, struct elf_thread_status, list));
1846 }
1847
1848 kfree(info->prstatus);
1849 kfree(info->psinfo);
1850 kfree(info->notes);
1851 kfree(info->fpu);
1852#ifdef ELF_CORE_COPY_XFPREGS
1853 kfree(info->xfpu);
1854#endif
1855}
1856
Roland McGrath4206d3a2008-01-30 13:31:45 +01001857#endif
1858
Roland McGrathf47aef52007-01-26 00:56:49 -08001859static struct vm_area_struct *first_vma(struct task_struct *tsk,
1860 struct vm_area_struct *gate_vma)
1861{
1862 struct vm_area_struct *ret = tsk->mm->mmap;
1863
1864 if (ret)
1865 return ret;
1866 return gate_vma;
1867}
1868/*
1869 * Helper function for iterating across a vma list. It ensures that the caller
1870 * will visit `gate_vma' prior to terminating the search.
1871 */
1872static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma,
1873 struct vm_area_struct *gate_vma)
1874{
1875 struct vm_area_struct *ret;
1876
1877 ret = this_vma->vm_next;
1878 if (ret)
1879 return ret;
1880 if (this_vma == gate_vma)
1881 return NULL;
1882 return gate_vma;
1883}
1884
Linus Torvalds1da177e2005-04-16 15:20:36 -07001885/*
1886 * Actual dumper
1887 *
1888 * This is a two-pass process; first we find the offsets of the bits,
1889 * and then they are actually written out. If we run out of core limit
1890 * we just truncate.
1891 */
Neil Horman7dc0b222007-10-16 23:26:34 -07001892static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001893{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001894 int has_dumped = 0;
1895 mm_segment_t fs;
1896 int segs;
1897 size_t size = 0;
Roland McGrathf47aef52007-01-26 00:56:49 -08001898 struct vm_area_struct *vma, *gate_vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001899 struct elfhdr *elf = NULL;
Andi Kleend025c9d2006-09-30 23:29:28 -07001900 loff_t offset = 0, dataoff, foffset;
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001901 unsigned long mm_flags;
Roland McGrath3aba4812008-01-30 13:31:44 +01001902 struct elf_note_info info;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001903
1904 /*
1905 * We no longer stop all VM operations.
1906 *
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001907 * This is because those proceses that could possibly change map_count
1908 * or the mmap / vma pages are now blocked in do_exit on current
1909 * finishing this core dump.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001910 *
1911 * Only ptrace can touch these memory addresses, but it doesn't change
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001912 * the map_count or the pages allocated. So no possibility of crashing
Linus Torvalds1da177e2005-04-16 15:20:36 -07001913 * exists while dumping the mm->vm_next areas to the core file.
1914 */
1915
1916 /* alloc memory for large data structures: too large to be on stack */
1917 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1918 if (!elf)
WANG Cong5f719552008-05-06 12:45:35 +08001919 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001920
1921 segs = current->mm->map_count;
1922#ifdef ELF_CORE_EXTRA_PHDRS
1923 segs += ELF_CORE_EXTRA_PHDRS;
1924#endif
1925
Roland McGrathf47aef52007-01-26 00:56:49 -08001926 gate_vma = get_gate_vma(current);
1927 if (gate_vma != NULL)
1928 segs++;
1929
Roland McGrath3aba4812008-01-30 13:31:44 +01001930 /*
1931 * Collect all the non-memory information about the process for the
1932 * notes. This also sets up the file header.
1933 */
1934 if (!fill_note_info(elf, segs + 1, /* including notes section */
1935 &info, signr, regs))
1936 goto cleanup;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001937
1938 has_dumped = 1;
1939 current->flags |= PF_DUMPCORE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001940
1941 fs = get_fs();
1942 set_fs(KERNEL_DS);
1943
1944 DUMP_WRITE(elf, sizeof(*elf));
1945 offset += sizeof(*elf); /* Elf header */
Petr Vandroveca7a0d862006-10-13 18:42:07 +02001946 offset += (segs + 1) * sizeof(struct elf_phdr); /* Program headers */
1947 foffset = offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001948
1949 /* Write notes phdr entry */
1950 {
1951 struct elf_phdr phdr;
Roland McGrath3aba4812008-01-30 13:31:44 +01001952 size_t sz = get_note_info_size(&info);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001953
Michael Ellermane5501492007-09-19 14:38:12 +10001954 sz += elf_coredump_extra_notes_size();
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01001955
Linus Torvalds1da177e2005-04-16 15:20:36 -07001956 fill_elf_note_phdr(&phdr, sz, offset);
1957 offset += sz;
1958 DUMP_WRITE(&phdr, sizeof(phdr));
1959 }
1960
Linus Torvalds1da177e2005-04-16 15:20:36 -07001961 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1962
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001963 /*
1964 * We must use the same mm->flags while dumping core to avoid
1965 * inconsistency between the program headers and bodies, otherwise an
1966 * unusable core file can be generated.
1967 */
1968 mm_flags = current->mm->flags;
1969
Linus Torvalds1da177e2005-04-16 15:20:36 -07001970 /* Write program headers for segments dump */
Roland McGrathf47aef52007-01-26 00:56:49 -08001971 for (vma = first_vma(current, gate_vma); vma != NULL;
1972 vma = next_vma(vma, gate_vma)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001973 struct elf_phdr phdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001974
1975 phdr.p_type = PT_LOAD;
1976 phdr.p_offset = offset;
1977 phdr.p_vaddr = vma->vm_start;
1978 phdr.p_paddr = 0;
Roland McGrath82df3972007-10-16 23:27:02 -07001979 phdr.p_filesz = vma_dump_size(vma, mm_flags);
1980 phdr.p_memsz = vma->vm_end - vma->vm_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001981 offset += phdr.p_filesz;
1982 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001983 if (vma->vm_flags & VM_WRITE)
1984 phdr.p_flags |= PF_W;
1985 if (vma->vm_flags & VM_EXEC)
1986 phdr.p_flags |= PF_X;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001987 phdr.p_align = ELF_EXEC_PAGESIZE;
1988
1989 DUMP_WRITE(&phdr, sizeof(phdr));
1990 }
1991
1992#ifdef ELF_CORE_WRITE_EXTRA_PHDRS
1993 ELF_CORE_WRITE_EXTRA_PHDRS;
1994#endif
1995
1996 /* write out the notes section */
Roland McGrath3aba4812008-01-30 13:31:44 +01001997 if (!write_note_info(&info, file, &foffset))
1998 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001999
Michael Ellermane5501492007-09-19 14:38:12 +10002000 if (elf_coredump_extra_notes_write(file, &foffset))
2001 goto end_coredump;
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01002002
Andi Kleend025c9d2006-09-30 23:29:28 -07002003 /* Align to page */
2004 DUMP_SEEK(dataoff - foffset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002005
Roland McGrathf47aef52007-01-26 00:56:49 -08002006 for (vma = first_vma(current, gate_vma); vma != NULL;
2007 vma = next_vma(vma, gate_vma)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002008 unsigned long addr;
Roland McGrath82df3972007-10-16 23:27:02 -07002009 unsigned long end;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002010
Roland McGrath82df3972007-10-16 23:27:02 -07002011 end = vma->vm_start + vma_dump_size(vma, mm_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002012
Roland McGrath82df3972007-10-16 23:27:02 -07002013 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002014 struct page *page;
WANG Cong4220b7f2008-04-29 01:01:18 -07002015 struct vm_area_struct *tmp_vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002016
2017 if (get_user_pages(current, current->mm, addr, 1, 0, 1,
WANG Cong4220b7f2008-04-29 01:01:18 -07002018 &page, &tmp_vma) <= 0) {
Andi Kleend025c9d2006-09-30 23:29:28 -07002019 DUMP_SEEK(PAGE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002020 } else {
Nick Piggin557ed1f2007-10-16 01:24:40 -07002021 if (page == ZERO_PAGE(0)) {
Brian Pomerantz03221702007-04-01 23:49:41 -07002022 if (!dump_seek(file, PAGE_SIZE)) {
2023 page_cache_release(page);
2024 goto end_coredump;
2025 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002026 } else {
2027 void *kaddr;
WANG Cong4220b7f2008-04-29 01:01:18 -07002028 flush_cache_page(tmp_vma, addr,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002029 page_to_pfn(page));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002030 kaddr = kmap(page);
2031 if ((size += PAGE_SIZE) > limit ||
2032 !dump_write(file, kaddr,
2033 PAGE_SIZE)) {
2034 kunmap(page);
2035 page_cache_release(page);
2036 goto end_coredump;
2037 }
2038 kunmap(page);
2039 }
2040 page_cache_release(page);
2041 }
2042 }
2043 }
2044
2045#ifdef ELF_CORE_WRITE_EXTRA_DATA
2046 ELF_CORE_WRITE_EXTRA_DATA;
2047#endif
2048
Linus Torvalds1da177e2005-04-16 15:20:36 -07002049end_coredump:
2050 set_fs(fs);
2051
2052cleanup:
Roland McGrath3aba4812008-01-30 13:31:44 +01002053 free_note_info(&info);
WANG Cong5f719552008-05-06 12:45:35 +08002054 kfree(elf);
2055out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002056 return has_dumped;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002057}
2058
2059#endif /* USE_ELF_CORE_DUMP */
2060
2061static int __init init_elf_binfmt(void)
2062{
2063 return register_binfmt(&elf_format);
2064}
2065
2066static void __exit exit_elf_binfmt(void)
2067{
2068 /* Remove the COFF and ELF loaders. */
2069 unregister_binfmt(&elf_format);
2070}
2071
2072core_initcall(init_elf_binfmt);
2073module_exit(exit_elf_binfmt);
2074MODULE_LICENSE("GPL");