blob: 655ed8d30a86ef7e963414a9cb56d6ed7dc5d3c4 [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 */
Andi Kleen612a95b2008-01-30 13:33:32 +0100686 SET_PERSONALITY(loc->elf_ex, 0);
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 */
Andi Kleen612a95b2008-01-30 13:33:32 +0100737 SET_PERSONALITY(loc->elf_ex, 0);
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. */
Andi Kleen612a95b2008-01-30 13:33:32 +0100751 SET_PERSONALITY(loc->elf_ex, 0);
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{
Roland McGrathe5b97dd2007-01-26 00:56:48 -08001159 /* The vma can be set up to tell us the answer directly. */
1160 if (vma->vm_flags & VM_ALWAYSDUMP)
Roland McGrath82df3972007-10-16 23:27:02 -07001161 goto whole;
Roland McGrathe5b97dd2007-01-26 00:56:48 -08001162
Linus Torvalds1da177e2005-04-16 15:20:36 -07001163 /* Do not dump I/O mapped devices or special mappings */
1164 if (vma->vm_flags & (VM_IO | VM_RESERVED))
1165 return 0;
1166
Roland McGrath82df3972007-10-16 23:27:02 -07001167#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1168
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001169 /* By default, dump shared memory if mapped from an anonymous file. */
1170 if (vma->vm_flags & VM_SHARED) {
Roland McGrath82df3972007-10-16 23:27:02 -07001171 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ?
1172 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
1173 goto whole;
1174 return 0;
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001175 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176
Roland McGrath82df3972007-10-16 23:27:02 -07001177 /* Dump segments that have been written to. */
1178 if (vma->anon_vma && FILTER(ANON_PRIVATE))
1179 goto whole;
1180 if (vma->vm_file == NULL)
1181 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001182
Roland McGrath82df3972007-10-16 23:27:02 -07001183 if (FILTER(MAPPED_PRIVATE))
1184 goto whole;
1185
1186 /*
1187 * If this looks like the beginning of a DSO or executable mapping,
1188 * check for an ELF header. If we find one, dump the first page to
1189 * aid in determining what was mapped here.
1190 */
1191 if (FILTER(ELF_HEADERS) && vma->vm_file != NULL && vma->vm_pgoff == 0) {
1192 u32 __user *header = (u32 __user *) vma->vm_start;
1193 u32 word;
1194 /*
1195 * Doing it this way gets the constant folded by GCC.
1196 */
1197 union {
1198 u32 cmp;
1199 char elfmag[SELFMAG];
1200 } magic;
1201 BUILD_BUG_ON(SELFMAG != sizeof word);
1202 magic.elfmag[EI_MAG0] = ELFMAG0;
1203 magic.elfmag[EI_MAG1] = ELFMAG1;
1204 magic.elfmag[EI_MAG2] = ELFMAG2;
1205 magic.elfmag[EI_MAG3] = ELFMAG3;
1206 if (get_user(word, header) == 0 && word == magic.cmp)
1207 return PAGE_SIZE;
1208 }
1209
1210#undef FILTER
1211
1212 return 0;
1213
1214whole:
1215 return vma->vm_end - vma->vm_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001216}
1217
Linus Torvalds1da177e2005-04-16 15:20:36 -07001218/* An ELF note in memory */
1219struct memelfnote
1220{
1221 const char *name;
1222 int type;
1223 unsigned int datasz;
1224 void *data;
1225};
1226
1227static int notesize(struct memelfnote *en)
1228{
1229 int sz;
1230
1231 sz = sizeof(struct elf_note);
1232 sz += roundup(strlen(en->name) + 1, 4);
1233 sz += roundup(en->datasz, 4);
1234
1235 return sz;
1236}
1237
Andi Kleend025c9d2006-09-30 23:29:28 -07001238#define DUMP_WRITE(addr, nr, foffset) \
1239 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001240
Andi Kleend025c9d2006-09-30 23:29:28 -07001241static int alignfile(struct file *file, loff_t *foffset)
1242{
Petr Vandroveca7a0d862006-10-13 18:42:07 +02001243 static const char buf[4] = { 0, };
Andi Kleend025c9d2006-09-30 23:29:28 -07001244 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
1245 return 1;
1246}
1247
1248static int writenote(struct memelfnote *men, struct file *file,
1249 loff_t *foffset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001250{
1251 struct elf_note en;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001252 en.n_namesz = strlen(men->name) + 1;
1253 en.n_descsz = men->datasz;
1254 en.n_type = men->type;
1255
Andi Kleend025c9d2006-09-30 23:29:28 -07001256 DUMP_WRITE(&en, sizeof(en), foffset);
1257 DUMP_WRITE(men->name, en.n_namesz, foffset);
1258 if (!alignfile(file, foffset))
1259 return 0;
1260 DUMP_WRITE(men->data, men->datasz, foffset);
1261 if (!alignfile(file, foffset))
1262 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263
1264 return 1;
1265}
1266#undef DUMP_WRITE
Linus Torvalds1da177e2005-04-16 15:20:36 -07001267
1268#define DUMP_WRITE(addr, nr) \
1269 if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
1270 goto end_coredump;
1271#define DUMP_SEEK(off) \
1272 if (!dump_seek(file, (off))) \
1273 goto end_coredump;
1274
Roland McGrath3aba4812008-01-30 13:31:44 +01001275static void fill_elf_header(struct elfhdr *elf, int segs,
1276 u16 machine, u32 flags, u8 osabi)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277{
Cyrill Gorcunov6970c8e2008-04-29 01:01:18 -07001278 memset(elf, 0, sizeof(*elf));
1279
Linus Torvalds1da177e2005-04-16 15:20:36 -07001280 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1281 elf->e_ident[EI_CLASS] = ELF_CLASS;
1282 elf->e_ident[EI_DATA] = ELF_DATA;
1283 elf->e_ident[EI_VERSION] = EV_CURRENT;
1284 elf->e_ident[EI_OSABI] = ELF_OSABI;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001285
1286 elf->e_type = ET_CORE;
Roland McGrath3aba4812008-01-30 13:31:44 +01001287 elf->e_machine = machine;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001288 elf->e_version = EV_CURRENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001289 elf->e_phoff = sizeof(struct elfhdr);
Roland McGrath3aba4812008-01-30 13:31:44 +01001290 elf->e_flags = flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001291 elf->e_ehsize = sizeof(struct elfhdr);
1292 elf->e_phentsize = sizeof(struct elf_phdr);
1293 elf->e_phnum = segs;
Cyrill Gorcunov6970c8e2008-04-29 01:01:18 -07001294
Linus Torvalds1da177e2005-04-16 15:20:36 -07001295 return;
1296}
1297
Andrew Morton8d6b5eee2006-09-25 23:32:04 -07001298static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299{
1300 phdr->p_type = PT_NOTE;
1301 phdr->p_offset = offset;
1302 phdr->p_vaddr = 0;
1303 phdr->p_paddr = 0;
1304 phdr->p_filesz = sz;
1305 phdr->p_memsz = 0;
1306 phdr->p_flags = 0;
1307 phdr->p_align = 0;
1308 return;
1309}
1310
1311static void fill_note(struct memelfnote *note, const char *name, int type,
1312 unsigned int sz, void *data)
1313{
1314 note->name = name;
1315 note->type = type;
1316 note->datasz = sz;
1317 note->data = data;
1318 return;
1319}
1320
1321/*
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001322 * fill up all the fields in prstatus from the given task struct, except
1323 * registers which need to be filled up separately.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001324 */
1325static void fill_prstatus(struct elf_prstatus *prstatus,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001326 struct task_struct *p, long signr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001327{
1328 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1329 prstatus->pr_sigpend = p->pending.signal.sig[0];
1330 prstatus->pr_sighold = p->blocked.sig[0];
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001331 prstatus->pr_pid = task_pid_vnr(p);
Roland McGrath45626bb2008-01-07 14:22:44 -08001332 prstatus->pr_ppid = task_pid_vnr(p->real_parent);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001333 prstatus->pr_pgrp = task_pgrp_vnr(p);
1334 prstatus->pr_sid = task_session_vnr(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001335 if (thread_group_leader(p)) {
1336 /*
1337 * This is the record for the group leader. Add in the
1338 * cumulative times of previous dead threads. This total
1339 * won't include the time of each live thread whose state
1340 * is included in the core dump. The final total reported
1341 * to our parent process when it calls wait4 will include
1342 * those sums as well as the little bit more time it takes
1343 * this and each other thread to finish dying after the
1344 * core dump synchronization phase.
1345 */
1346 cputime_to_timeval(cputime_add(p->utime, p->signal->utime),
1347 &prstatus->pr_utime);
1348 cputime_to_timeval(cputime_add(p->stime, p->signal->stime),
1349 &prstatus->pr_stime);
1350 } else {
1351 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1352 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1353 }
1354 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1355 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1356}
1357
1358static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1359 struct mm_struct *mm)
1360{
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -07001361 unsigned int i, len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001362
1363 /* first copy the parameters from user space */
1364 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1365
1366 len = mm->arg_end - mm->arg_start;
1367 if (len >= ELF_PRARGSZ)
1368 len = ELF_PRARGSZ-1;
1369 if (copy_from_user(&psinfo->pr_psargs,
1370 (const char __user *)mm->arg_start, len))
1371 return -EFAULT;
1372 for(i = 0; i < len; i++)
1373 if (psinfo->pr_psargs[i] == 0)
1374 psinfo->pr_psargs[i] = ' ';
1375 psinfo->pr_psargs[len] = 0;
1376
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001377 psinfo->pr_pid = task_pid_vnr(p);
Roland McGrath45626bb2008-01-07 14:22:44 -08001378 psinfo->pr_ppid = task_pid_vnr(p->real_parent);
Pavel Emelyanovb4888932007-10-18 23:40:14 -07001379 psinfo->pr_pgrp = task_pgrp_vnr(p);
1380 psinfo->pr_sid = task_session_vnr(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001381
1382 i = p->state ? ffz(~p->state) + 1 : 0;
1383 psinfo->pr_state = i;
Carsten Otte55148542006-03-25 03:08:22 -08001384 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001385 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1386 psinfo->pr_nice = task_nice(p);
1387 psinfo->pr_flag = p->flags;
1388 SET_UID(psinfo->pr_uid, p->uid);
1389 SET_GID(psinfo->pr_gid, p->gid);
1390 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1391
1392 return 0;
1393}
1394
Roland McGrath3aba4812008-01-30 13:31:44 +01001395static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
1396{
1397 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
1398 int i = 0;
1399 do
1400 i += 2;
1401 while (auxv[i - 2] != AT_NULL);
1402 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
1403}
1404
Roland McGrath4206d3a2008-01-30 13:31:45 +01001405#ifdef CORE_DUMP_USE_REGSET
1406#include <linux/regset.h>
1407
1408struct elf_thread_core_info {
1409 struct elf_thread_core_info *next;
1410 struct task_struct *task;
1411 struct elf_prstatus prstatus;
1412 struct memelfnote notes[0];
1413};
1414
1415struct elf_note_info {
1416 struct elf_thread_core_info *thread;
1417 struct memelfnote psinfo;
1418 struct memelfnote auxv;
1419 size_t size;
1420 int thread_notes;
1421};
1422
Roland McGrathd31472b2008-03-04 14:28:30 -08001423/*
1424 * When a regset has a writeback hook, we call it on each thread before
1425 * dumping user memory. On register window machines, this makes sure the
1426 * user memory backing the register data is up to date before we read it.
1427 */
1428static void do_thread_regset_writeback(struct task_struct *task,
1429 const struct user_regset *regset)
1430{
1431 if (regset->writeback)
1432 regset->writeback(task, regset, 1);
1433}
1434
Roland McGrath4206d3a2008-01-30 13:31:45 +01001435static int fill_thread_core_info(struct elf_thread_core_info *t,
1436 const struct user_regset_view *view,
1437 long signr, size_t *total)
1438{
1439 unsigned int i;
1440
1441 /*
1442 * NT_PRSTATUS is the one special case, because the regset data
1443 * goes into the pr_reg field inside the note contents, rather
1444 * than being the whole note contents. We fill the reset in here.
1445 * We assume that regset 0 is NT_PRSTATUS.
1446 */
1447 fill_prstatus(&t->prstatus, t->task, signr);
1448 (void) view->regsets[0].get(t->task, &view->regsets[0],
1449 0, sizeof(t->prstatus.pr_reg),
1450 &t->prstatus.pr_reg, NULL);
1451
1452 fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
1453 sizeof(t->prstatus), &t->prstatus);
1454 *total += notesize(&t->notes[0]);
1455
Roland McGrathd31472b2008-03-04 14:28:30 -08001456 do_thread_regset_writeback(t->task, &view->regsets[0]);
1457
Roland McGrath4206d3a2008-01-30 13:31:45 +01001458 /*
1459 * Each other regset might generate a note too. For each regset
1460 * that has no core_note_type or is inactive, we leave t->notes[i]
1461 * all zero and we'll know to skip writing it later.
1462 */
1463 for (i = 1; i < view->n; ++i) {
1464 const struct user_regset *regset = &view->regsets[i];
Roland McGrathd31472b2008-03-04 14:28:30 -08001465 do_thread_regset_writeback(t->task, regset);
Roland McGrath4206d3a2008-01-30 13:31:45 +01001466 if (regset->core_note_type &&
1467 (!regset->active || regset->active(t->task, regset))) {
1468 int ret;
1469 size_t size = regset->n * regset->size;
1470 void *data = kmalloc(size, GFP_KERNEL);
1471 if (unlikely(!data))
1472 return 0;
1473 ret = regset->get(t->task, regset,
1474 0, size, data, NULL);
1475 if (unlikely(ret))
1476 kfree(data);
1477 else {
1478 if (regset->core_note_type != NT_PRFPREG)
1479 fill_note(&t->notes[i], "LINUX",
1480 regset->core_note_type,
1481 size, data);
1482 else {
1483 t->prstatus.pr_fpvalid = 1;
1484 fill_note(&t->notes[i], "CORE",
1485 NT_PRFPREG, size, data);
1486 }
1487 *total += notesize(&t->notes[i]);
1488 }
1489 }
1490 }
1491
1492 return 1;
1493}
1494
1495static int fill_note_info(struct elfhdr *elf, int phdrs,
1496 struct elf_note_info *info,
1497 long signr, struct pt_regs *regs)
1498{
1499 struct task_struct *dump_task = current;
1500 const struct user_regset_view *view = task_user_regset_view(dump_task);
1501 struct elf_thread_core_info *t;
1502 struct elf_prpsinfo *psinfo;
Oleg Nesterov83914442008-07-25 01:47:45 -07001503 struct core_thread *ct;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001504 unsigned int i;
1505
1506 info->size = 0;
1507 info->thread = NULL;
1508
1509 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1510 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1511
1512 if (psinfo == NULL)
1513 return 0;
1514
1515 /*
1516 * Figure out how many notes we're going to need for each thread.
1517 */
1518 info->thread_notes = 0;
1519 for (i = 0; i < view->n; ++i)
1520 if (view->regsets[i].core_note_type != 0)
1521 ++info->thread_notes;
1522
1523 /*
1524 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1525 * since it is our one special case.
1526 */
1527 if (unlikely(info->thread_notes == 0) ||
1528 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
1529 WARN_ON(1);
1530 return 0;
1531 }
1532
1533 /*
1534 * Initialize the ELF file header.
1535 */
1536 fill_elf_header(elf, phdrs,
1537 view->e_machine, view->e_flags, view->ei_osabi);
1538
1539 /*
1540 * Allocate a structure for each thread.
1541 */
Oleg Nesterov83914442008-07-25 01:47:45 -07001542 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) {
1543 t = kzalloc(offsetof(struct elf_thread_core_info,
1544 notes[info->thread_notes]),
1545 GFP_KERNEL);
1546 if (unlikely(!t))
1547 return 0;
Oleg Nesterov24d52882008-07-25 01:47:40 -07001548
Oleg Nesterov83914442008-07-25 01:47:45 -07001549 t->task = ct->task;
1550 if (ct->task == dump_task || !info->thread) {
1551 t->next = info->thread;
1552 info->thread = t;
1553 } else {
1554 /*
1555 * Make sure to keep the original task at
1556 * the head of the list.
1557 */
1558 t->next = info->thread->next;
1559 info->thread->next = t;
Roland McGrath4206d3a2008-01-30 13:31:45 +01001560 }
Oleg Nesterov83914442008-07-25 01:47:45 -07001561 }
Roland McGrath4206d3a2008-01-30 13:31:45 +01001562
1563 /*
1564 * Now fill in each thread's information.
1565 */
1566 for (t = info->thread; t != NULL; t = t->next)
1567 if (!fill_thread_core_info(t, view, signr, &info->size))
1568 return 0;
1569
1570 /*
1571 * Fill in the two process-wide notes.
1572 */
1573 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
1574 info->size += notesize(&info->psinfo);
1575
1576 fill_auxv_note(&info->auxv, current->mm);
1577 info->size += notesize(&info->auxv);
1578
1579 return 1;
1580}
1581
1582static size_t get_note_info_size(struct elf_note_info *info)
1583{
1584 return info->size;
1585}
1586
1587/*
1588 * Write all the notes for each thread. When writing the first thread, the
1589 * process-wide notes are interleaved after the first thread-specific note.
1590 */
1591static int write_note_info(struct elf_note_info *info,
1592 struct file *file, loff_t *foffset)
1593{
1594 bool first = 1;
1595 struct elf_thread_core_info *t = info->thread;
1596
1597 do {
1598 int i;
1599
1600 if (!writenote(&t->notes[0], file, foffset))
1601 return 0;
1602
1603 if (first && !writenote(&info->psinfo, file, foffset))
1604 return 0;
1605 if (first && !writenote(&info->auxv, file, foffset))
1606 return 0;
1607
1608 for (i = 1; i < info->thread_notes; ++i)
1609 if (t->notes[i].data &&
1610 !writenote(&t->notes[i], file, foffset))
1611 return 0;
1612
1613 first = 0;
1614 t = t->next;
1615 } while (t);
1616
1617 return 1;
1618}
1619
1620static void free_note_info(struct elf_note_info *info)
1621{
1622 struct elf_thread_core_info *threads = info->thread;
1623 while (threads) {
1624 unsigned int i;
1625 struct elf_thread_core_info *t = threads;
1626 threads = t->next;
1627 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
1628 for (i = 1; i < info->thread_notes; ++i)
1629 kfree(t->notes[i].data);
1630 kfree(t);
1631 }
1632 kfree(info->psinfo.data);
1633}
1634
1635#else
1636
Linus Torvalds1da177e2005-04-16 15:20:36 -07001637/* Here is the structure in which status of each thread is captured. */
1638struct elf_thread_status
1639{
1640 struct list_head list;
1641 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1642 elf_fpregset_t fpu; /* NT_PRFPREG */
1643 struct task_struct *thread;
1644#ifdef ELF_CORE_COPY_XFPREGS
Mark Nelson5b20cd82007-10-16 23:25:39 -07001645 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001646#endif
1647 struct memelfnote notes[3];
1648 int num_notes;
1649};
1650
1651/*
1652 * In order to add the specific thread information for the elf file format,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001653 * we need to keep a linked list of every threads pr_status and then create
1654 * a single section for them in the final core file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001655 */
1656static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1657{
1658 int sz = 0;
1659 struct task_struct *p = t->thread;
1660 t->num_notes = 0;
1661
1662 fill_prstatus(&t->prstatus, p, signr);
1663 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1664
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001665 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1666 &(t->prstatus));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001667 t->num_notes++;
1668 sz += notesize(&t->notes[0]);
1669
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001670 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1671 &t->fpu))) {
1672 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1673 &(t->fpu));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001674 t->num_notes++;
1675 sz += notesize(&t->notes[1]);
1676 }
1677
1678#ifdef ELF_CORE_COPY_XFPREGS
1679 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
Mark Nelson5b20cd82007-10-16 23:25:39 -07001680 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1681 sizeof(t->xfpu), &t->xfpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001682 t->num_notes++;
1683 sz += notesize(&t->notes[2]);
1684 }
1685#endif
1686 return sz;
1687}
1688
Roland McGrath3aba4812008-01-30 13:31:44 +01001689struct elf_note_info {
1690 struct memelfnote *notes;
1691 struct elf_prstatus *prstatus; /* NT_PRSTATUS */
1692 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */
1693 struct list_head thread_list;
1694 elf_fpregset_t *fpu;
1695#ifdef ELF_CORE_COPY_XFPREGS
1696 elf_fpxregset_t *xfpu;
1697#endif
1698 int thread_status_size;
1699 int numnote;
1700};
1701
1702static int fill_note_info(struct elfhdr *elf, int phdrs,
1703 struct elf_note_info *info,
1704 long signr, struct pt_regs *regs)
1705{
1706#define NUM_NOTES 6
1707 struct list_head *t;
Roland McGrath3aba4812008-01-30 13:31:44 +01001708
1709 info->notes = NULL;
1710 info->prstatus = NULL;
1711 info->psinfo = NULL;
1712 info->fpu = NULL;
1713#ifdef ELF_CORE_COPY_XFPREGS
1714 info->xfpu = NULL;
1715#endif
1716 INIT_LIST_HEAD(&info->thread_list);
1717
1718 info->notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote),
1719 GFP_KERNEL);
1720 if (!info->notes)
1721 return 0;
1722 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
1723 if (!info->psinfo)
1724 return 0;
1725 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
1726 if (!info->prstatus)
1727 return 0;
1728 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
1729 if (!info->fpu)
1730 return 0;
1731#ifdef ELF_CORE_COPY_XFPREGS
1732 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
1733 if (!info->xfpu)
1734 return 0;
1735#endif
1736
1737 info->thread_status_size = 0;
1738 if (signr) {
Oleg Nesterov83914442008-07-25 01:47:45 -07001739 struct core_thread *ct;
WANG Cong4220b7f2008-04-29 01:01:18 -07001740 struct elf_thread_status *ets;
Oleg Nesterov24d52882008-07-25 01:47:40 -07001741
Oleg Nesterov83914442008-07-25 01:47:45 -07001742 for (ct = current->mm->core_state->dumper.next;
1743 ct; ct = ct->next) {
1744 ets = kzalloc(sizeof(*ets), GFP_KERNEL);
1745 if (!ets)
1746 return 0;
1747
1748 ets->thread = ct->task;
1749 list_add(&ets->list, &info->thread_list);
1750 }
1751
Roland McGrath3aba4812008-01-30 13:31:44 +01001752 list_for_each(t, &info->thread_list) {
Roland McGrath3aba4812008-01-30 13:31:44 +01001753 int sz;
1754
WANG Cong4220b7f2008-04-29 01:01:18 -07001755 ets = list_entry(t, struct elf_thread_status, list);
1756 sz = elf_dump_thread_status(signr, ets);
Roland McGrath3aba4812008-01-30 13:31:44 +01001757 info->thread_status_size += sz;
1758 }
1759 }
1760 /* now collect the dump for the current */
1761 memset(info->prstatus, 0, sizeof(*info->prstatus));
1762 fill_prstatus(info->prstatus, current, signr);
1763 elf_core_copy_regs(&info->prstatus->pr_reg, regs);
1764
1765 /* Set up header */
1766 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI);
1767
1768 /*
1769 * Set up the notes in similar form to SVR4 core dumps made
1770 * with info from their /proc.
1771 */
1772
1773 fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
1774 sizeof(*info->prstatus), info->prstatus);
1775 fill_psinfo(info->psinfo, current->group_leader, current->mm);
1776 fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
1777 sizeof(*info->psinfo), info->psinfo);
1778
1779 info->numnote = 2;
1780
1781 fill_auxv_note(&info->notes[info->numnote++], current->mm);
1782
1783 /* Try to dump the FPU. */
1784 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
1785 info->fpu);
1786 if (info->prstatus->pr_fpvalid)
1787 fill_note(info->notes + info->numnote++,
1788 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
1789#ifdef ELF_CORE_COPY_XFPREGS
1790 if (elf_core_copy_task_xfpregs(current, info->xfpu))
1791 fill_note(info->notes + info->numnote++,
1792 "LINUX", ELF_CORE_XFPREG_TYPE,
1793 sizeof(*info->xfpu), info->xfpu);
1794#endif
1795
1796 return 1;
1797
1798#undef NUM_NOTES
1799}
1800
1801static size_t get_note_info_size(struct elf_note_info *info)
1802{
1803 int sz = 0;
1804 int i;
1805
1806 for (i = 0; i < info->numnote; i++)
1807 sz += notesize(info->notes + i);
1808
1809 sz += info->thread_status_size;
1810
1811 return sz;
1812}
1813
1814static int write_note_info(struct elf_note_info *info,
1815 struct file *file, loff_t *foffset)
1816{
1817 int i;
1818 struct list_head *t;
1819
1820 for (i = 0; i < info->numnote; i++)
1821 if (!writenote(info->notes + i, file, foffset))
1822 return 0;
1823
1824 /* write out the thread status notes section */
1825 list_for_each(t, &info->thread_list) {
1826 struct elf_thread_status *tmp =
1827 list_entry(t, struct elf_thread_status, list);
1828
1829 for (i = 0; i < tmp->num_notes; i++)
1830 if (!writenote(&tmp->notes[i], file, foffset))
1831 return 0;
1832 }
1833
1834 return 1;
1835}
1836
1837static void free_note_info(struct elf_note_info *info)
1838{
1839 while (!list_empty(&info->thread_list)) {
1840 struct list_head *tmp = info->thread_list.next;
1841 list_del(tmp);
1842 kfree(list_entry(tmp, struct elf_thread_status, list));
1843 }
1844
1845 kfree(info->prstatus);
1846 kfree(info->psinfo);
1847 kfree(info->notes);
1848 kfree(info->fpu);
1849#ifdef ELF_CORE_COPY_XFPREGS
1850 kfree(info->xfpu);
1851#endif
1852}
1853
Roland McGrath4206d3a2008-01-30 13:31:45 +01001854#endif
1855
Roland McGrathf47aef52007-01-26 00:56:49 -08001856static struct vm_area_struct *first_vma(struct task_struct *tsk,
1857 struct vm_area_struct *gate_vma)
1858{
1859 struct vm_area_struct *ret = tsk->mm->mmap;
1860
1861 if (ret)
1862 return ret;
1863 return gate_vma;
1864}
1865/*
1866 * Helper function for iterating across a vma list. It ensures that the caller
1867 * will visit `gate_vma' prior to terminating the search.
1868 */
1869static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma,
1870 struct vm_area_struct *gate_vma)
1871{
1872 struct vm_area_struct *ret;
1873
1874 ret = this_vma->vm_next;
1875 if (ret)
1876 return ret;
1877 if (this_vma == gate_vma)
1878 return NULL;
1879 return gate_vma;
1880}
1881
Linus Torvalds1da177e2005-04-16 15:20:36 -07001882/*
1883 * Actual dumper
1884 *
1885 * This is a two-pass process; first we find the offsets of the bits,
1886 * and then they are actually written out. If we run out of core limit
1887 * we just truncate.
1888 */
Neil Horman7dc0b222007-10-16 23:26:34 -07001889static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001890{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001891 int has_dumped = 0;
1892 mm_segment_t fs;
1893 int segs;
1894 size_t size = 0;
Roland McGrathf47aef52007-01-26 00:56:49 -08001895 struct vm_area_struct *vma, *gate_vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001896 struct elfhdr *elf = NULL;
Andi Kleend025c9d2006-09-30 23:29:28 -07001897 loff_t offset = 0, dataoff, foffset;
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001898 unsigned long mm_flags;
Roland McGrath3aba4812008-01-30 13:31:44 +01001899 struct elf_note_info info;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001900
1901 /*
1902 * We no longer stop all VM operations.
1903 *
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001904 * This is because those proceses that could possibly change map_count
1905 * or the mmap / vma pages are now blocked in do_exit on current
1906 * finishing this core dump.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001907 *
1908 * Only ptrace can touch these memory addresses, but it doesn't change
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001909 * the map_count or the pages allocated. So no possibility of crashing
Linus Torvalds1da177e2005-04-16 15:20:36 -07001910 * exists while dumping the mm->vm_next areas to the core file.
1911 */
1912
1913 /* alloc memory for large data structures: too large to be on stack */
1914 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1915 if (!elf)
WANG Cong5f719552008-05-06 12:45:35 +08001916 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001917
1918 segs = current->mm->map_count;
1919#ifdef ELF_CORE_EXTRA_PHDRS
1920 segs += ELF_CORE_EXTRA_PHDRS;
1921#endif
1922
Roland McGrathf47aef52007-01-26 00:56:49 -08001923 gate_vma = get_gate_vma(current);
1924 if (gate_vma != NULL)
1925 segs++;
1926
Roland McGrath3aba4812008-01-30 13:31:44 +01001927 /*
1928 * Collect all the non-memory information about the process for the
1929 * notes. This also sets up the file header.
1930 */
1931 if (!fill_note_info(elf, segs + 1, /* including notes section */
1932 &info, signr, regs))
1933 goto cleanup;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001934
1935 has_dumped = 1;
1936 current->flags |= PF_DUMPCORE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001937
1938 fs = get_fs();
1939 set_fs(KERNEL_DS);
1940
1941 DUMP_WRITE(elf, sizeof(*elf));
1942 offset += sizeof(*elf); /* Elf header */
Petr Vandroveca7a0d862006-10-13 18:42:07 +02001943 offset += (segs + 1) * sizeof(struct elf_phdr); /* Program headers */
1944 foffset = offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001945
1946 /* Write notes phdr entry */
1947 {
1948 struct elf_phdr phdr;
Roland McGrath3aba4812008-01-30 13:31:44 +01001949 size_t sz = get_note_info_size(&info);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001950
Michael Ellermane5501492007-09-19 14:38:12 +10001951 sz += elf_coredump_extra_notes_size();
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01001952
Linus Torvalds1da177e2005-04-16 15:20:36 -07001953 fill_elf_note_phdr(&phdr, sz, offset);
1954 offset += sz;
1955 DUMP_WRITE(&phdr, sizeof(phdr));
1956 }
1957
Linus Torvalds1da177e2005-04-16 15:20:36 -07001958 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1959
Kawai, Hidehiroa1b59e82007-07-19 01:48:29 -07001960 /*
1961 * We must use the same mm->flags while dumping core to avoid
1962 * inconsistency between the program headers and bodies, otherwise an
1963 * unusable core file can be generated.
1964 */
1965 mm_flags = current->mm->flags;
1966
Linus Torvalds1da177e2005-04-16 15:20:36 -07001967 /* Write program headers for segments dump */
Roland McGrathf47aef52007-01-26 00:56:49 -08001968 for (vma = first_vma(current, gate_vma); vma != NULL;
1969 vma = next_vma(vma, gate_vma)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001970 struct elf_phdr phdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001971
1972 phdr.p_type = PT_LOAD;
1973 phdr.p_offset = offset;
1974 phdr.p_vaddr = vma->vm_start;
1975 phdr.p_paddr = 0;
Roland McGrath82df3972007-10-16 23:27:02 -07001976 phdr.p_filesz = vma_dump_size(vma, mm_flags);
1977 phdr.p_memsz = vma->vm_end - vma->vm_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001978 offset += phdr.p_filesz;
1979 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001980 if (vma->vm_flags & VM_WRITE)
1981 phdr.p_flags |= PF_W;
1982 if (vma->vm_flags & VM_EXEC)
1983 phdr.p_flags |= PF_X;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001984 phdr.p_align = ELF_EXEC_PAGESIZE;
1985
1986 DUMP_WRITE(&phdr, sizeof(phdr));
1987 }
1988
1989#ifdef ELF_CORE_WRITE_EXTRA_PHDRS
1990 ELF_CORE_WRITE_EXTRA_PHDRS;
1991#endif
1992
1993 /* write out the notes section */
Roland McGrath3aba4812008-01-30 13:31:44 +01001994 if (!write_note_info(&info, file, &foffset))
1995 goto end_coredump;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001996
Michael Ellermane5501492007-09-19 14:38:12 +10001997 if (elf_coredump_extra_notes_write(file, &foffset))
1998 goto end_coredump;
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01001999
Andi Kleend025c9d2006-09-30 23:29:28 -07002000 /* Align to page */
2001 DUMP_SEEK(dataoff - foffset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002002
Roland McGrathf47aef52007-01-26 00:56:49 -08002003 for (vma = first_vma(current, gate_vma); vma != NULL;
2004 vma = next_vma(vma, gate_vma)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002005 unsigned long addr;
Roland McGrath82df3972007-10-16 23:27:02 -07002006 unsigned long end;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002007
Roland McGrath82df3972007-10-16 23:27:02 -07002008 end = vma->vm_start + vma_dump_size(vma, mm_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002009
Roland McGrath82df3972007-10-16 23:27:02 -07002010 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002011 struct page *page;
WANG Cong4220b7f2008-04-29 01:01:18 -07002012 struct vm_area_struct *tmp_vma;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002013
2014 if (get_user_pages(current, current->mm, addr, 1, 0, 1,
WANG Cong4220b7f2008-04-29 01:01:18 -07002015 &page, &tmp_vma) <= 0) {
Andi Kleend025c9d2006-09-30 23:29:28 -07002016 DUMP_SEEK(PAGE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002017 } else {
Nick Piggin557ed1f2007-10-16 01:24:40 -07002018 if (page == ZERO_PAGE(0)) {
Brian Pomerantz03221702007-04-01 23:49:41 -07002019 if (!dump_seek(file, PAGE_SIZE)) {
2020 page_cache_release(page);
2021 goto end_coredump;
2022 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002023 } else {
2024 void *kaddr;
WANG Cong4220b7f2008-04-29 01:01:18 -07002025 flush_cache_page(tmp_vma, addr,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07002026 page_to_pfn(page));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002027 kaddr = kmap(page);
2028 if ((size += PAGE_SIZE) > limit ||
2029 !dump_write(file, kaddr,
2030 PAGE_SIZE)) {
2031 kunmap(page);
2032 page_cache_release(page);
2033 goto end_coredump;
2034 }
2035 kunmap(page);
2036 }
2037 page_cache_release(page);
2038 }
2039 }
2040 }
2041
2042#ifdef ELF_CORE_WRITE_EXTRA_DATA
2043 ELF_CORE_WRITE_EXTRA_DATA;
2044#endif
2045
Linus Torvalds1da177e2005-04-16 15:20:36 -07002046end_coredump:
2047 set_fs(fs);
2048
2049cleanup:
Roland McGrath3aba4812008-01-30 13:31:44 +01002050 free_note_info(&info);
WANG Cong5f719552008-05-06 12:45:35 +08002051 kfree(elf);
2052out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002053 return has_dumped;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002054}
2055
2056#endif /* USE_ELF_CORE_DUMP */
2057
2058static int __init init_elf_binfmt(void)
2059{
2060 return register_binfmt(&elf_format);
2061}
2062
2063static void __exit exit_elf_binfmt(void)
2064{
2065 /* Remove the COFF and ELF loaders. */
2066 unregister_binfmt(&elf_format);
2067}
2068
2069core_initcall(init_elf_binfmt);
2070module_exit(exit_elf_binfmt);
2071MODULE_LICENSE("GPL");