blob: 7cb28720f90e363a4b74b2da8b575233ff5a6da1 [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>
19#include <linux/a.out.h>
20#include <linux/errno.h>
21#include <linux/signal.h>
22#include <linux/binfmts.h>
23#include <linux/string.h>
24#include <linux/file.h>
25#include <linux/fcntl.h>
26#include <linux/ptrace.h>
27#include <linux/slab.h>
28#include <linux/shm.h>
29#include <linux/personality.h>
30#include <linux/elfcore.h>
31#include <linux/init.h>
32#include <linux/highuid.h>
33#include <linux/smp.h>
34#include <linux/smp_lock.h>
35#include <linux/compiler.h>
36#include <linux/highmem.h>
37#include <linux/pagemap.h>
38#include <linux/security.h>
39#include <linux/syscalls.h>
40#include <linux/random.h>
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070041#include <linux/elf.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <asm/uaccess.h>
43#include <asm/param.h>
44#include <asm/page.h>
45
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070046static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs);
47static int load_elf_library(struct file *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070048static unsigned long elf_map (struct file *, unsigned long, struct elf_phdr *, int, int);
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)
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070055static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file);
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,
79 .min_coredump = ELF_EXEC_PAGESIZE
80};
81
Chuck Ebbertce510592006-07-03 00:24:14 -070082#define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
84static int set_brk(unsigned long start, unsigned long end)
85{
86 start = ELF_PAGEALIGN(start);
87 end = ELF_PAGEALIGN(end);
88 if (end > start) {
89 unsigned long addr;
90 down_write(&current->mm->mmap_sem);
91 addr = do_brk(start, end - start);
92 up_write(&current->mm->mmap_sem);
93 if (BAD_ADDR(addr))
94 return addr;
95 }
96 current->mm->start_brk = current->mm->brk = end;
97 return 0;
98}
99
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100/* We need to explicitly zero any fractional pages
101 after the data section (i.e. bss). This would
102 contain the junk from the file that should not
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700103 be in memory
104 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105static int padzero(unsigned long elf_bss)
106{
107 unsigned long nbyte;
108
109 nbyte = ELF_PAGEOFFSET(elf_bss);
110 if (nbyte) {
111 nbyte = ELF_MIN_ALIGN - nbyte;
112 if (clear_user((void __user *) elf_bss, nbyte))
113 return -EFAULT;
114 }
115 return 0;
116}
117
118/* Let's use some macros to make this stack manipulation a litle clearer */
119#ifdef CONFIG_STACK_GROWSUP
120#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
121#define STACK_ROUND(sp, items) \
122 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700123#define STACK_ALLOC(sp, len) ({ \
124 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
125 old_sp; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126#else
127#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
128#define STACK_ROUND(sp, items) \
129 (((unsigned long) (sp - items)) &~ 15UL)
130#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
131#endif
132
133static int
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700134create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 int interp_aout, unsigned long load_addr,
136 unsigned long interp_load_addr)
137{
138 unsigned long p = bprm->p;
139 int argc = bprm->argc;
140 int envc = bprm->envc;
141 elf_addr_t __user *argv;
142 elf_addr_t __user *envp;
143 elf_addr_t __user *sp;
144 elf_addr_t __user *u_platform;
145 const char *k_platform = ELF_PLATFORM;
146 int items;
147 elf_addr_t *elf_info;
148 int ei_index = 0;
149 struct task_struct *tsk = current;
150
151 /*
152 * If this architecture has a platform capability string, copy it
153 * to userspace. In some cases (Sparc), this info is impossible
154 * for userspace to get any other way, in others (i386) it is
155 * merely difficult.
156 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 u_platform = NULL;
158 if (k_platform) {
159 size_t len = strlen(k_platform) + 1;
160
161 /*
162 * In some cases (e.g. Hyper-Threading), we want to avoid L1
163 * evictions by the processes running on the same package. One
164 * thing we can do is to shuffle the initial stack for them.
165 */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700166
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 p = arch_align_stack(p);
168
169 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
170 if (__copy_to_user(u_platform, k_platform, len))
171 return -EFAULT;
172 }
173
174 /* Create the ELF interpreter info */
Jesper Juhl785d5572006-06-23 02:05:35 -0700175 elf_info = (elf_addr_t *)current->mm->saved_auxv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176#define NEW_AUX_ENT(id, val) \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700177 do { \
Jesper Juhl785d5572006-06-23 02:05:35 -0700178 elf_info[ei_index++] = id; \
179 elf_info[ei_index++] = val; \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700180 } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181
182#ifdef ARCH_DLINFO
183 /*
184 * ARCH_DLINFO must come first so PPC can do its special alignment of
185 * AUXV.
186 */
187 ARCH_DLINFO;
188#endif
189 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
190 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
191 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
192 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700193 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
195 NEW_AUX_ENT(AT_BASE, interp_load_addr);
196 NEW_AUX_ENT(AT_FLAGS, 0);
197 NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
Jesper Juhl785d5572006-06-23 02:05:35 -0700198 NEW_AUX_ENT(AT_UID, tsk->uid);
199 NEW_AUX_ENT(AT_EUID, tsk->euid);
200 NEW_AUX_ENT(AT_GID, tsk->gid);
201 NEW_AUX_ENT(AT_EGID, tsk->egid);
202 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 if (k_platform) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700204 NEW_AUX_ENT(AT_PLATFORM,
Jesper Juhl785d5572006-06-23 02:05:35 -0700205 (elf_addr_t)(unsigned long)u_platform);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206 }
207 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
Jesper Juhl785d5572006-06-23 02:05:35 -0700208 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 }
210#undef NEW_AUX_ENT
211 /* AT_NULL is zero; clear the rest too */
212 memset(&elf_info[ei_index], 0,
213 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
214
215 /* And advance past the AT_NULL entry. */
216 ei_index += 2;
217
218 sp = STACK_ADD(p, ei_index);
219
220 items = (argc + 1) + (envc + 1);
221 if (interp_aout) {
222 items += 3; /* a.out interpreters require argv & envp too */
223 } else {
224 items += 1; /* ELF interpreters only put argc on the stack */
225 }
226 bprm->p = STACK_ROUND(sp, items);
227
228 /* Point sp at the lowest address on the stack */
229#ifdef CONFIG_STACK_GROWSUP
230 sp = (elf_addr_t __user *)bprm->p - items - ei_index;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700231 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232#else
233 sp = (elf_addr_t __user *)bprm->p;
234#endif
235
236 /* Now, let's put argc (and argv, envp if appropriate) on the stack */
237 if (__put_user(argc, sp++))
238 return -EFAULT;
239 if (interp_aout) {
240 argv = sp + 2;
241 envp = argv + argc + 1;
Heiko Carstens841d5fb2006-12-06 20:36:35 -0800242 if (__put_user((elf_addr_t)(unsigned long)argv, sp++) ||
243 __put_user((elf_addr_t)(unsigned long)envp, sp++))
244 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 } else {
246 argv = sp;
247 envp = argv + argc + 1;
248 }
249
250 /* Populate argv and envp */
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -0700251 p = current->mm->arg_end = current->mm->arg_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 while (argc-- > 0) {
253 size_t len;
Heiko Carstens841d5fb2006-12-06 20:36:35 -0800254 if (__put_user((elf_addr_t)p, argv++))
255 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
257 if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
258 return 0;
259 p += len;
260 }
261 if (__put_user(0, argv))
262 return -EFAULT;
263 current->mm->arg_end = current->mm->env_start = p;
264 while (envc-- > 0) {
265 size_t len;
Heiko Carstens841d5fb2006-12-06 20:36:35 -0800266 if (__put_user((elf_addr_t)p, envp++))
267 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
269 if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
270 return 0;
271 p += len;
272 }
273 if (__put_user(0, envp))
274 return -EFAULT;
275 current->mm->env_end = p;
276
277 /* Put the elf_info on the stack in the right place. */
278 sp = (elf_addr_t __user *)envp + 1;
279 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
280 return -EFAULT;
281 return 0;
282}
283
284#ifndef elf_map
285
286static unsigned long elf_map(struct file *filep, unsigned long addr,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700287 struct elf_phdr *eppnt, int prot, int type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288{
289 unsigned long map_addr;
David Gibsondda6ebd2006-01-08 01:03:35 -0800290 unsigned long pageoffset = ELF_PAGEOFFSET(eppnt->p_vaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291
292 down_write(&current->mm->mmap_sem);
David Gibsondda6ebd2006-01-08 01:03:35 -0800293 /* mmap() will return -EINVAL if given a zero size, but a
294 * segment with zero filesize is perfectly valid */
295 if (eppnt->p_filesz + pageoffset)
296 map_addr = do_mmap(filep, ELF_PAGESTART(addr),
297 eppnt->p_filesz + pageoffset, prot, type,
298 eppnt->p_offset - pageoffset);
299 else
300 map_addr = ELF_PAGESTART(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 up_write(&current->mm->mmap_sem);
302 return(map_addr);
303}
304
305#endif /* !elf_map */
306
307/* This is much more generalized than the library routine read function,
308 so we keep this separate. Technically the library read function
309 is only provided so that we can read a.out libraries that have
310 an ELF header */
311
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700312static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
313 struct file *interpreter, unsigned long *interp_load_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314{
315 struct elf_phdr *elf_phdata;
316 struct elf_phdr *eppnt;
317 unsigned long load_addr = 0;
318 int load_addr_set = 0;
319 unsigned long last_bss = 0, elf_bss = 0;
320 unsigned long error = ~0UL;
321 int retval, i, size;
322
323 /* First of all, some simple consistency checks */
324 if (interp_elf_ex->e_type != ET_EXEC &&
325 interp_elf_ex->e_type != ET_DYN)
326 goto out;
327 if (!elf_check_arch(interp_elf_ex))
328 goto out;
329 if (!interpreter->f_op || !interpreter->f_op->mmap)
330 goto out;
331
332 /*
333 * If the size of this structure has changed, then punt, since
334 * we will be doing the wrong thing.
335 */
336 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
337 goto out;
338 if (interp_elf_ex->e_phnum < 1 ||
339 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
340 goto out;
341
342 /* Now read in all of the header information */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
344 if (size > ELF_MIN_ALIGN)
345 goto out;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700346 elf_phdata = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347 if (!elf_phdata)
348 goto out;
349
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700350 retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
351 (char *)elf_phdata,size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 error = -EIO;
353 if (retval != size) {
354 if (retval < 0)
355 error = retval;
356 goto out_close;
357 }
358
359 eppnt = elf_phdata;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700360 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
361 if (eppnt->p_type == PT_LOAD) {
362 int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
363 int elf_prot = 0;
364 unsigned long vaddr = 0;
365 unsigned long k, map_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700367 if (eppnt->p_flags & PF_R)
368 elf_prot = PROT_READ;
369 if (eppnt->p_flags & PF_W)
370 elf_prot |= PROT_WRITE;
371 if (eppnt->p_flags & PF_X)
372 elf_prot |= PROT_EXEC;
373 vaddr = eppnt->p_vaddr;
374 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
375 elf_type |= MAP_FIXED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700377 map_addr = elf_map(interpreter, load_addr + vaddr,
378 eppnt, elf_prot, elf_type);
379 error = map_addr;
380 if (BAD_ADDR(map_addr))
381 goto out_close;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700383 if (!load_addr_set &&
384 interp_elf_ex->e_type == ET_DYN) {
385 load_addr = map_addr - ELF_PAGESTART(vaddr);
386 load_addr_set = 1;
387 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700389 /*
390 * Check to see if the section's size will overflow the
391 * allowed task size. Note that p_filesz must always be
392 * <= p_memsize so it's only necessary to check p_memsz.
393 */
394 k = load_addr + eppnt->p_vaddr;
Chuck Ebbertce510592006-07-03 00:24:14 -0700395 if (BAD_ADDR(k) ||
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700396 eppnt->p_filesz > eppnt->p_memsz ||
397 eppnt->p_memsz > TASK_SIZE ||
398 TASK_SIZE - eppnt->p_memsz < k) {
399 error = -ENOMEM;
400 goto out_close;
401 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700403 /*
404 * Find the end of the file mapping for this phdr, and
405 * keep track of the largest address we see for this.
406 */
407 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
408 if (k > elf_bss)
409 elf_bss = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700411 /*
412 * Do the same thing for the memory mapping - between
413 * elf_bss and last_bss is the bss section.
414 */
415 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
416 if (k > last_bss)
417 last_bss = k;
418 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 }
420
421 /*
422 * Now fill out the bss section. First pad the last page up
423 * to the page boundary, and then perform a mmap to make sure
424 * that there are zero-mapped pages up to and including the
425 * last bss page.
426 */
427 if (padzero(elf_bss)) {
428 error = -EFAULT;
429 goto out_close;
430 }
431
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700432 /* What we have mapped so far */
433 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434
435 /* Map the last of the bss segment */
436 if (last_bss > elf_bss) {
437 down_write(&current->mm->mmap_sem);
438 error = do_brk(elf_bss, last_bss - elf_bss);
439 up_write(&current->mm->mmap_sem);
440 if (BAD_ADDR(error))
441 goto out_close;
442 }
443
444 *interp_load_addr = load_addr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700445 error = ((unsigned long)interp_elf_ex->e_entry) + load_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446
447out_close:
448 kfree(elf_phdata);
449out:
450 return error;
451}
452
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700453static unsigned long load_aout_interp(struct exec *interp_ex,
454 struct file *interpreter)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455{
456 unsigned long text_data, elf_entry = ~0UL;
457 char __user * addr;
458 loff_t offset;
459
460 current->mm->end_code = interp_ex->a_text;
461 text_data = interp_ex->a_text + interp_ex->a_data;
462 current->mm->end_data = text_data;
463 current->mm->brk = interp_ex->a_bss + text_data;
464
465 switch (N_MAGIC(*interp_ex)) {
466 case OMAGIC:
467 offset = 32;
468 addr = (char __user *)0;
469 break;
470 case ZMAGIC:
471 case QMAGIC:
472 offset = N_TXTOFF(*interp_ex);
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700473 addr = (char __user *)N_TXTADDR(*interp_ex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 break;
475 default:
476 goto out;
477 }
478
479 down_write(&current->mm->mmap_sem);
480 do_brk(0, text_data);
481 up_write(&current->mm->mmap_sem);
482 if (!interpreter->f_op || !interpreter->f_op->read)
483 goto out;
484 if (interpreter->f_op->read(interpreter, addr, text_data, &offset) < 0)
485 goto out;
486 flush_icache_range((unsigned long)addr,
487 (unsigned long)addr + text_data);
488
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 down_write(&current->mm->mmap_sem);
490 do_brk(ELF_PAGESTART(text_data + ELF_MIN_ALIGN - 1),
491 interp_ex->a_bss);
492 up_write(&current->mm->mmap_sem);
493 elf_entry = interp_ex->a_entry;
494
495out:
496 return elf_entry;
497}
498
499/*
500 * These are the functions used to load ELF style executables and shared
501 * libraries. There is no binary dependent code anywhere else.
502 */
503
504#define INTERPRETER_NONE 0
505#define INTERPRETER_AOUT 1
506#define INTERPRETER_ELF 2
507
Andi Kleen913bd902006-03-25 16:29:09 +0100508#ifndef STACK_RND_MASK
509#define STACK_RND_MASK 0x7ff /* with 4K pages 8MB of VA */
510#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511
512static unsigned long randomize_stack_top(unsigned long stack_top)
513{
514 unsigned int random_variable = 0;
515
Andi Kleenc16b63e2006-09-26 10:52:28 +0200516 if ((current->flags & PF_RANDOMIZE) &&
517 !(current->personality & ADDR_NO_RANDOMIZE)) {
Andi Kleen913bd902006-03-25 16:29:09 +0100518 random_variable = get_random_int() & STACK_RND_MASK;
519 random_variable <<= PAGE_SHIFT;
520 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521#ifdef CONFIG_STACK_GROWSUP
Andi Kleen913bd902006-03-25 16:29:09 +0100522 return PAGE_ALIGN(stack_top) + random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523#else
Andi Kleen913bd902006-03-25 16:29:09 +0100524 return PAGE_ALIGN(stack_top) - random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525#endif
526}
527
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700528static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529{
530 struct file *interpreter = NULL; /* to shut gcc up */
531 unsigned long load_addr = 0, load_bias = 0;
532 int load_addr_set = 0;
533 char * elf_interpreter = NULL;
534 unsigned int interpreter_type = INTERPRETER_NONE;
535 unsigned char ibcs2_interpreter = 0;
536 unsigned long error;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700537 struct elf_phdr *elf_ppnt, *elf_phdata;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 unsigned long elf_bss, elf_brk;
539 int elf_exec_fileno;
540 int retval, i;
541 unsigned int size;
542 unsigned long elf_entry, interp_load_addr = 0;
543 unsigned long start_code, end_code, start_data, end_data;
544 unsigned long reloc_func_desc = 0;
545 char passed_fileno[6];
546 struct files_struct *files;
David Rientjes8de61e62006-12-06 20:40:16 -0800547 int executable_stack = EXSTACK_DEFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 unsigned long def_flags = 0;
549 struct {
550 struct elfhdr elf_ex;
551 struct elfhdr interp_elf_ex;
552 struct exec interp_ex;
553 } *loc;
554
555 loc = kmalloc(sizeof(*loc), GFP_KERNEL);
556 if (!loc) {
557 retval = -ENOMEM;
558 goto out_ret;
559 }
560
561 /* Get the exec-header */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700562 loc->elf_ex = *((struct elfhdr *)bprm->buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563
564 retval = -ENOEXEC;
565 /* First of all, some simple consistency checks */
566 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
567 goto out;
568
569 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
570 goto out;
571 if (!elf_check_arch(&loc->elf_ex))
572 goto out;
573 if (!bprm->file->f_op||!bprm->file->f_op->mmap)
574 goto out;
575
576 /* Now read in all of the header information */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr))
578 goto out;
579 if (loc->elf_ex.e_phnum < 1 ||
580 loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr))
581 goto out;
582 size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr);
583 retval = -ENOMEM;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700584 elf_phdata = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 if (!elf_phdata)
586 goto out;
587
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700588 retval = kernel_read(bprm->file, loc->elf_ex.e_phoff,
589 (char *)elf_phdata, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 if (retval != size) {
591 if (retval >= 0)
592 retval = -EIO;
593 goto out_free_ph;
594 }
595
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700596 files = current->files; /* Refcounted so ok */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 retval = unshare_files();
598 if (retval < 0)
599 goto out_free_ph;
600 if (files == current->files) {
601 put_files_struct(files);
602 files = NULL;
603 }
604
605 /* exec will make our files private anyway, but for the a.out
606 loader stuff we need to do it earlier */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 retval = get_unused_fd();
608 if (retval < 0)
609 goto out_free_fh;
610 get_file(bprm->file);
611 fd_install(elf_exec_fileno = retval, bprm->file);
612
613 elf_ppnt = elf_phdata;
614 elf_bss = 0;
615 elf_brk = 0;
616
617 start_code = ~0UL;
618 end_code = 0;
619 start_data = 0;
620 end_data = 0;
621
622 for (i = 0; i < loc->elf_ex.e_phnum; i++) {
623 if (elf_ppnt->p_type == PT_INTERP) {
624 /* This is the program interpreter used for
625 * shared libraries - for now assume that this
626 * is an a.out format binary
627 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628 retval = -ENOEXEC;
629 if (elf_ppnt->p_filesz > PATH_MAX ||
630 elf_ppnt->p_filesz < 2)
631 goto out_free_file;
632
633 retval = -ENOMEM;
Jesper Juhl792db3a2006-01-09 20:54:45 -0800634 elf_interpreter = kmalloc(elf_ppnt->p_filesz,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700635 GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636 if (!elf_interpreter)
637 goto out_free_file;
638
639 retval = kernel_read(bprm->file, elf_ppnt->p_offset,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700640 elf_interpreter,
641 elf_ppnt->p_filesz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642 if (retval != elf_ppnt->p_filesz) {
643 if (retval >= 0)
644 retval = -EIO;
645 goto out_free_interp;
646 }
647 /* make sure path is NULL terminated */
648 retval = -ENOEXEC;
649 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
650 goto out_free_interp;
651
652 /* If the program interpreter is one of these two,
653 * then assume an iBCS2 image. Otherwise assume
654 * a native linux image.
655 */
656 if (strcmp(elf_interpreter,"/usr/lib/libc.so.1") == 0 ||
657 strcmp(elf_interpreter,"/usr/lib/ld.so.1") == 0)
658 ibcs2_interpreter = 1;
659
660 /*
661 * The early SET_PERSONALITY here is so that the lookup
662 * for the interpreter happens in the namespace of the
663 * to-be-execed image. SET_PERSONALITY can select an
664 * alternate root.
665 *
666 * However, SET_PERSONALITY is NOT allowed to switch
667 * this task into the new images's memory mapping
668 * policy - that is, TASK_SIZE must still evaluate to
669 * that which is appropriate to the execing application.
670 * This is because exit_mmap() needs to have TASK_SIZE
671 * evaluate to the size of the old image.
672 *
673 * So if (say) a 64-bit application is execing a 32-bit
674 * application it is the architecture's responsibility
675 * to defer changing the value of TASK_SIZE until the
676 * switch really is going to happen - do this in
677 * flush_thread(). - akpm
678 */
679 SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter);
680
681 interpreter = open_exec(elf_interpreter);
682 retval = PTR_ERR(interpreter);
683 if (IS_ERR(interpreter))
684 goto out_free_interp;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700685 retval = kernel_read(interpreter, 0, bprm->buf,
686 BINPRM_BUF_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 if (retval != BINPRM_BUF_SIZE) {
688 if (retval >= 0)
689 retval = -EIO;
690 goto out_free_dentry;
691 }
692
693 /* Get the exec headers */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700694 loc->interp_ex = *((struct exec *)bprm->buf);
695 loc->interp_elf_ex = *((struct elfhdr *)bprm->buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 break;
697 }
698 elf_ppnt++;
699 }
700
701 elf_ppnt = elf_phdata;
702 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
703 if (elf_ppnt->p_type == PT_GNU_STACK) {
704 if (elf_ppnt->p_flags & PF_X)
705 executable_stack = EXSTACK_ENABLE_X;
706 else
707 executable_stack = EXSTACK_DISABLE_X;
708 break;
709 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710
711 /* Some simple consistency checks for the interpreter */
712 if (elf_interpreter) {
713 interpreter_type = INTERPRETER_ELF | INTERPRETER_AOUT;
714
715 /* Now figure out which format our binary is */
716 if ((N_MAGIC(loc->interp_ex) != OMAGIC) &&
717 (N_MAGIC(loc->interp_ex) != ZMAGIC) &&
718 (N_MAGIC(loc->interp_ex) != QMAGIC))
719 interpreter_type = INTERPRETER_ELF;
720
721 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
722 interpreter_type &= ~INTERPRETER_ELF;
723
724 retval = -ELIBBAD;
725 if (!interpreter_type)
726 goto out_free_dentry;
727
728 /* Make sure only one type was selected */
729 if ((interpreter_type & INTERPRETER_ELF) &&
730 interpreter_type != INTERPRETER_ELF) {
731 // FIXME - ratelimit this before re-enabling
732 // printk(KERN_WARNING "ELF: Ambiguous type, using ELF\n");
733 interpreter_type = INTERPRETER_ELF;
734 }
735 /* Verify the interpreter has a valid arch */
736 if ((interpreter_type == INTERPRETER_ELF) &&
737 !elf_check_arch(&loc->interp_elf_ex))
738 goto out_free_dentry;
739 } else {
740 /* Executables without an interpreter also need a personality */
741 SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter);
742 }
743
744 /* OK, we are done with that, now set up the arg stuff,
745 and then start this sucker up */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746 if ((!bprm->sh_bang) && (interpreter_type == INTERPRETER_AOUT)) {
747 char *passed_p = passed_fileno;
748 sprintf(passed_fileno, "%d", elf_exec_fileno);
749
750 if (elf_interpreter) {
751 retval = copy_strings_kernel(1, &passed_p, bprm);
752 if (retval)
753 goto out_free_dentry;
754 bprm->argc++;
755 }
756 }
757
758 /* Flush all traces of the currently running executable */
759 retval = flush_old_exec(bprm);
760 if (retval)
761 goto out_free_dentry;
762
763 /* Discard our unneeded old files struct */
764 if (files) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 put_files_struct(files);
766 files = NULL;
767 }
768
769 /* OK, This is the point of no return */
770 current->mm->start_data = 0;
771 current->mm->end_data = 0;
772 current->mm->end_code = 0;
773 current->mm->mmap = NULL;
774 current->flags &= ~PF_FORKNOEXEC;
775 current->mm->def_flags = def_flags;
776
777 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
778 may depend on the personality. */
779 SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter);
780 if (elf_read_implies_exec(loc->elf_ex, executable_stack))
781 current->personality |= READ_IMPLIES_EXEC;
782
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700783 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 current->flags |= PF_RANDOMIZE;
785 arch_pick_mmap_layout(current->mm);
786
787 /* Do this so that we can load the interpreter, if need be. We will
788 change some of these later */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 current->mm->free_area_cache = current->mm->mmap_base;
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700790 current->mm->cached_hole_size = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
792 executable_stack);
793 if (retval < 0) {
794 send_sig(SIGKILL, current, 0);
795 goto out_free_dentry;
796 }
797
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 current->mm->start_stack = bprm->p;
799
800 /* Now we do a little grungy work by mmaping the ELF image into
801 the correct location in memory. At this point, we assume that
802 the image should be loaded at fixed address, not at a variable
803 address. */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700804 for(i = 0, elf_ppnt = elf_phdata;
805 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 int elf_prot = 0, elf_flags;
807 unsigned long k, vaddr;
808
809 if (elf_ppnt->p_type != PT_LOAD)
810 continue;
811
812 if (unlikely (elf_brk > elf_bss)) {
813 unsigned long nbyte;
814
815 /* There was a PT_LOAD segment with p_memsz > p_filesz
816 before this one. Map anonymous pages, if needed,
817 and clear the area. */
818 retval = set_brk (elf_bss + load_bias,
819 elf_brk + load_bias);
820 if (retval) {
821 send_sig(SIGKILL, current, 0);
822 goto out_free_dentry;
823 }
824 nbyte = ELF_PAGEOFFSET(elf_bss);
825 if (nbyte) {
826 nbyte = ELF_MIN_ALIGN - nbyte;
827 if (nbyte > elf_brk - elf_bss)
828 nbyte = elf_brk - elf_bss;
829 if (clear_user((void __user *)elf_bss +
830 load_bias, nbyte)) {
831 /*
832 * This bss-zeroing can fail if the ELF
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700833 * file specifies odd protections. So
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 * we don't check the return value
835 */
836 }
837 }
838 }
839
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700840 if (elf_ppnt->p_flags & PF_R)
841 elf_prot |= PROT_READ;
842 if (elf_ppnt->p_flags & PF_W)
843 elf_prot |= PROT_WRITE;
844 if (elf_ppnt->p_flags & PF_X)
845 elf_prot |= PROT_EXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700847 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848
849 vaddr = elf_ppnt->p_vaddr;
850 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
851 elf_flags |= MAP_FIXED;
852 } else if (loc->elf_ex.e_type == ET_DYN) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700853 /* Try and get dynamic programs out of the way of the
854 * default mmap base, as well as whatever program they
855 * might try to exec. This is because the brk will
856 * follow the loader, and is not movable. */
Linus Torvalds90cb28e2007-01-06 13:28:21 -0800857 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858 }
859
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700860 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
861 elf_prot, elf_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 if (BAD_ADDR(error)) {
863 send_sig(SIGKILL, current, 0);
864 goto out_free_dentry;
865 }
866
867 if (!load_addr_set) {
868 load_addr_set = 1;
869 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
870 if (loc->elf_ex.e_type == ET_DYN) {
871 load_bias += error -
872 ELF_PAGESTART(load_bias + vaddr);
873 load_addr += load_bias;
874 reloc_func_desc = load_bias;
875 }
876 }
877 k = elf_ppnt->p_vaddr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700878 if (k < start_code)
879 start_code = k;
880 if (start_data < k)
881 start_data = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882
883 /*
884 * Check to see if the section's size will overflow the
885 * allowed task size. Note that p_filesz must always be
886 * <= p_memsz so it is only necessary to check p_memsz.
887 */
Chuck Ebbertce510592006-07-03 00:24:14 -0700888 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 elf_ppnt->p_memsz > TASK_SIZE ||
890 TASK_SIZE - elf_ppnt->p_memsz < k) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700891 /* set_brk can never work. Avoid overflows. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892 send_sig(SIGKILL, current, 0);
893 goto out_free_dentry;
894 }
895
896 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
897
898 if (k > elf_bss)
899 elf_bss = k;
900 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
901 end_code = k;
902 if (end_data < k)
903 end_data = k;
904 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
905 if (k > elf_brk)
906 elf_brk = k;
907 }
908
909 loc->elf_ex.e_entry += load_bias;
910 elf_bss += load_bias;
911 elf_brk += load_bias;
912 start_code += load_bias;
913 end_code += load_bias;
914 start_data += load_bias;
915 end_data += load_bias;
916
917 /* Calling set_brk effectively mmaps the pages that we need
918 * for the bss and break sections. We must do this before
919 * mapping in the interpreter, to make sure it doesn't wind
920 * up getting placed where the bss needs to go.
921 */
922 retval = set_brk(elf_bss, elf_brk);
923 if (retval) {
924 send_sig(SIGKILL, current, 0);
925 goto out_free_dentry;
926 }
akpm@osdl.org6de50512005-10-11 08:29:08 -0700927 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928 send_sig(SIGSEGV, current, 0);
929 retval = -EFAULT; /* Nobody gets to see this, but.. */
930 goto out_free_dentry;
931 }
932
933 if (elf_interpreter) {
934 if (interpreter_type == INTERPRETER_AOUT)
935 elf_entry = load_aout_interp(&loc->interp_ex,
936 interpreter);
937 else
938 elf_entry = load_elf_interp(&loc->interp_elf_ex,
939 interpreter,
940 &interp_load_addr);
941 if (BAD_ADDR(elf_entry)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942 force_sig(SIGSEGV, current);
Chuck Ebbertce510592006-07-03 00:24:14 -0700943 retval = IS_ERR((void *)elf_entry) ?
944 (int)elf_entry : -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 goto out_free_dentry;
946 }
947 reloc_func_desc = interp_load_addr;
948
949 allow_write_access(interpreter);
950 fput(interpreter);
951 kfree(elf_interpreter);
952 } else {
953 elf_entry = loc->elf_ex.e_entry;
Suresh Siddha5342fba2006-02-26 04:18:28 +0100954 if (BAD_ADDR(elf_entry)) {
Chuck Ebbertce510592006-07-03 00:24:14 -0700955 force_sig(SIGSEGV, current);
956 retval = -EINVAL;
Suresh Siddha5342fba2006-02-26 04:18:28 +0100957 goto out_free_dentry;
958 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700959 }
960
961 kfree(elf_phdata);
962
963 if (interpreter_type != INTERPRETER_AOUT)
964 sys_close(elf_exec_fileno);
965
966 set_binfmt(&elf_format);
967
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -0700968#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
969 retval = arch_setup_additional_pages(bprm, executable_stack);
970 if (retval < 0) {
971 send_sig(SIGKILL, current, 0);
Roland McGrath18c8baf2005-04-28 15:17:19 -0700972 goto out;
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -0700973 }
974#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
975
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976 compute_creds(bprm);
977 current->flags &= ~PF_FORKNOEXEC;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700978 create_elf_tables(bprm, &loc->elf_ex,
979 (interpreter_type == INTERPRETER_AOUT),
980 load_addr, interp_load_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 /* N.B. passed_fileno might not be initialized? */
982 if (interpreter_type == INTERPRETER_AOUT)
983 current->mm->arg_start += strlen(passed_fileno) + 1;
984 current->mm->end_code = end_code;
985 current->mm->start_code = start_code;
986 current->mm->start_data = start_data;
987 current->mm->end_data = end_data;
988 current->mm->start_stack = bprm->p;
989
990 if (current->personality & MMAP_PAGE_ZERO) {
991 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
992 and some applications "depend" upon this behavior.
993 Since we do not have the power to recompile these, we
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700994 emulate the SVr4 behavior. Sigh. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 down_write(&current->mm->mmap_sem);
996 error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
997 MAP_FIXED | MAP_PRIVATE, 0);
998 up_write(&current->mm->mmap_sem);
999 }
1000
1001#ifdef ELF_PLAT_INIT
1002 /*
1003 * The ABI may specify that certain registers be set up in special
1004 * ways (on i386 %edx is the address of a DT_FINI function, for
1005 * example. In addition, it may also specify (eg, PowerPC64 ELF)
1006 * that the e_entry field is the address of the function descriptor
1007 * for the startup routine, rather than the address of the startup
1008 * routine itself. This macro performs whatever initialization to
1009 * the regs structure is required as well as any relocations to the
1010 * function descriptor entries when executing dynamically links apps.
1011 */
1012 ELF_PLAT_INIT(regs, reloc_func_desc);
1013#endif
1014
1015 start_thread(regs, elf_entry, bprm->p);
1016 if (unlikely(current->ptrace & PT_PTRACED)) {
1017 if (current->ptrace & PT_TRACE_EXEC)
1018 ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP);
1019 else
1020 send_sig(SIGTRAP, current, 0);
1021 }
1022 retval = 0;
1023out:
1024 kfree(loc);
1025out_ret:
1026 return retval;
1027
1028 /* error cleanup */
1029out_free_dentry:
1030 allow_write_access(interpreter);
1031 if (interpreter)
1032 fput(interpreter);
1033out_free_interp:
Jesper Juhlf99d49a2005-11-07 01:01:34 -08001034 kfree(elf_interpreter);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035out_free_file:
1036 sys_close(elf_exec_fileno);
1037out_free_fh:
Kirill Korotaev3b9b8ab2006-09-29 02:00:05 -07001038 if (files)
1039 reset_files_struct(current, files);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040out_free_ph:
1041 kfree(elf_phdata);
1042 goto out;
1043}
1044
1045/* This is really simpleminded and specialized - we are loading an
1046 a.out library that is given an ELF header. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001047static int load_elf_library(struct file *file)
1048{
1049 struct elf_phdr *elf_phdata;
1050 struct elf_phdr *eppnt;
1051 unsigned long elf_bss, bss, len;
1052 int retval, error, i, j;
1053 struct elfhdr elf_ex;
1054
1055 error = -ENOEXEC;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001056 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001057 if (retval != sizeof(elf_ex))
1058 goto out;
1059
1060 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
1061 goto out;
1062
1063 /* First of all, some simple consistency checks */
1064 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001065 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066 goto out;
1067
1068 /* Now read in all of the header information */
1069
1070 j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
1071 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1072
1073 error = -ENOMEM;
1074 elf_phdata = kmalloc(j, GFP_KERNEL);
1075 if (!elf_phdata)
1076 goto out;
1077
1078 eppnt = elf_phdata;
1079 error = -ENOEXEC;
1080 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
1081 if (retval != j)
1082 goto out_free_ph;
1083
1084 for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
1085 if ((eppnt + i)->p_type == PT_LOAD)
1086 j++;
1087 if (j != 1)
1088 goto out_free_ph;
1089
1090 while (eppnt->p_type != PT_LOAD)
1091 eppnt++;
1092
1093 /* Now use mmap to map the library into memory. */
1094 down_write(&current->mm->mmap_sem);
1095 error = do_mmap(file,
1096 ELF_PAGESTART(eppnt->p_vaddr),
1097 (eppnt->p_filesz +
1098 ELF_PAGEOFFSET(eppnt->p_vaddr)),
1099 PROT_READ | PROT_WRITE | PROT_EXEC,
1100 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
1101 (eppnt->p_offset -
1102 ELF_PAGEOFFSET(eppnt->p_vaddr)));
1103 up_write(&current->mm->mmap_sem);
1104 if (error != ELF_PAGESTART(eppnt->p_vaddr))
1105 goto out_free_ph;
1106
1107 elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
1108 if (padzero(elf_bss)) {
1109 error = -EFAULT;
1110 goto out_free_ph;
1111 }
1112
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001113 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
1114 ELF_MIN_ALIGN - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001115 bss = eppnt->p_memsz + eppnt->p_vaddr;
1116 if (bss > len) {
1117 down_write(&current->mm->mmap_sem);
1118 do_brk(len, bss - len);
1119 up_write(&current->mm->mmap_sem);
1120 }
1121 error = 0;
1122
1123out_free_ph:
1124 kfree(elf_phdata);
1125out:
1126 return error;
1127}
1128
1129/*
1130 * Note that some platforms still use traditional core dumps and not
1131 * the ELF core dump. Each platform can select it as appropriate.
1132 */
Matt Mackall708e9a72006-01-08 01:05:25 -08001133#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001134
1135/*
1136 * ELF core dumper
1137 *
1138 * Modelled on fs/exec.c:aout_core_dump()
1139 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1140 */
1141/*
1142 * These are the only things you should do on a core-file: use only these
1143 * functions to write out all the necessary info.
1144 */
1145static int dump_write(struct file *file, const void *addr, int nr)
1146{
1147 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
1148}
1149
Daniel Jacobowitz5db92852005-06-15 22:26:34 -07001150static int dump_seek(struct file *file, loff_t off)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001151{
Andi Kleend025c9d2006-09-30 23:29:28 -07001152 if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
Petr Vandrovec7f14daa2006-10-13 04:13:16 +02001153 if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154 return 0;
Andi Kleend025c9d2006-09-30 23:29:28 -07001155 } else {
1156 char *buf = (char *)get_zeroed_page(GFP_KERNEL);
1157 if (!buf)
1158 return 0;
1159 while (off > 0) {
1160 unsigned long n = off;
1161 if (n > PAGE_SIZE)
1162 n = PAGE_SIZE;
1163 if (!dump_write(file, buf, n))
1164 return 0;
1165 off -= n;
1166 }
1167 free_page((unsigned long)buf);
1168 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001169 return 1;
1170}
1171
1172/*
1173 * Decide whether a segment is worth dumping; default is yes to be
1174 * sure (missing info is worse than too much; etc).
1175 * Personally I'd include everything, and use the coredump limit...
1176 *
1177 * I think we should skip something. But I am not sure how. H.J.
1178 */
1179static int maydump(struct vm_area_struct *vma)
1180{
1181 /* Do not dump I/O mapped devices or special mappings */
1182 if (vma->vm_flags & (VM_IO | VM_RESERVED))
1183 return 0;
1184
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001185 /* Dump shared memory only if mapped from an anonymous file. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001186 if (vma->vm_flags & VM_SHARED)
Josef "Jeff" Sipek0f7fc9e2006-12-08 02:36:35 -08001187 return vma->vm_file->f_path.dentry->d_inode->i_nlink == 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001188
1189 /* If it hasn't been written to, don't write it out */
1190 if (!vma->anon_vma)
1191 return 0;
1192
1193 return 1;
1194}
1195
Linus Torvalds1da177e2005-04-16 15:20:36 -07001196/* An ELF note in memory */
1197struct memelfnote
1198{
1199 const char *name;
1200 int type;
1201 unsigned int datasz;
1202 void *data;
1203};
1204
1205static int notesize(struct memelfnote *en)
1206{
1207 int sz;
1208
1209 sz = sizeof(struct elf_note);
1210 sz += roundup(strlen(en->name) + 1, 4);
1211 sz += roundup(en->datasz, 4);
1212
1213 return sz;
1214}
1215
Andi Kleend025c9d2006-09-30 23:29:28 -07001216#define DUMP_WRITE(addr, nr, foffset) \
1217 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001218
Andi Kleend025c9d2006-09-30 23:29:28 -07001219static int alignfile(struct file *file, loff_t *foffset)
1220{
Petr Vandroveca7a0d862006-10-13 18:42:07 +02001221 static const char buf[4] = { 0, };
Andi Kleend025c9d2006-09-30 23:29:28 -07001222 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
1223 return 1;
1224}
1225
1226static int writenote(struct memelfnote *men, struct file *file,
1227 loff_t *foffset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001228{
1229 struct elf_note en;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001230 en.n_namesz = strlen(men->name) + 1;
1231 en.n_descsz = men->datasz;
1232 en.n_type = men->type;
1233
Andi Kleend025c9d2006-09-30 23:29:28 -07001234 DUMP_WRITE(&en, sizeof(en), foffset);
1235 DUMP_WRITE(men->name, en.n_namesz, foffset);
1236 if (!alignfile(file, foffset))
1237 return 0;
1238 DUMP_WRITE(men->data, men->datasz, foffset);
1239 if (!alignfile(file, foffset))
1240 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241
1242 return 1;
1243}
1244#undef DUMP_WRITE
Linus Torvalds1da177e2005-04-16 15:20:36 -07001245
1246#define DUMP_WRITE(addr, nr) \
1247 if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
1248 goto end_coredump;
1249#define DUMP_SEEK(off) \
1250 if (!dump_seek(file, (off))) \
1251 goto end_coredump;
1252
Arjan van de Ven858119e2006-01-14 13:20:43 -08001253static void fill_elf_header(struct elfhdr *elf, int segs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254{
1255 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1256 elf->e_ident[EI_CLASS] = ELF_CLASS;
1257 elf->e_ident[EI_DATA] = ELF_DATA;
1258 elf->e_ident[EI_VERSION] = EV_CURRENT;
1259 elf->e_ident[EI_OSABI] = ELF_OSABI;
1260 memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
1261
1262 elf->e_type = ET_CORE;
1263 elf->e_machine = ELF_ARCH;
1264 elf->e_version = EV_CURRENT;
1265 elf->e_entry = 0;
1266 elf->e_phoff = sizeof(struct elfhdr);
1267 elf->e_shoff = 0;
1268 elf->e_flags = ELF_CORE_EFLAGS;
1269 elf->e_ehsize = sizeof(struct elfhdr);
1270 elf->e_phentsize = sizeof(struct elf_phdr);
1271 elf->e_phnum = segs;
1272 elf->e_shentsize = 0;
1273 elf->e_shnum = 0;
1274 elf->e_shstrndx = 0;
1275 return;
1276}
1277
Andrew Morton8d6b5eee2006-09-25 23:32:04 -07001278static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001279{
1280 phdr->p_type = PT_NOTE;
1281 phdr->p_offset = offset;
1282 phdr->p_vaddr = 0;
1283 phdr->p_paddr = 0;
1284 phdr->p_filesz = sz;
1285 phdr->p_memsz = 0;
1286 phdr->p_flags = 0;
1287 phdr->p_align = 0;
1288 return;
1289}
1290
1291static void fill_note(struct memelfnote *note, const char *name, int type,
1292 unsigned int sz, void *data)
1293{
1294 note->name = name;
1295 note->type = type;
1296 note->datasz = sz;
1297 note->data = data;
1298 return;
1299}
1300
1301/*
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001302 * fill up all the fields in prstatus from the given task struct, except
1303 * registers which need to be filled up separately.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001304 */
1305static void fill_prstatus(struct elf_prstatus *prstatus,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001306 struct task_struct *p, long signr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001307{
1308 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1309 prstatus->pr_sigpend = p->pending.signal.sig[0];
1310 prstatus->pr_sighold = p->blocked.sig[0];
1311 prstatus->pr_pid = p->pid;
1312 prstatus->pr_ppid = p->parent->pid;
1313 prstatus->pr_pgrp = process_group(p);
Cedric Le Goater937949d2006-12-08 02:37:54 -08001314 prstatus->pr_sid = process_session(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001315 if (thread_group_leader(p)) {
1316 /*
1317 * This is the record for the group leader. Add in the
1318 * cumulative times of previous dead threads. This total
1319 * won't include the time of each live thread whose state
1320 * is included in the core dump. The final total reported
1321 * to our parent process when it calls wait4 will include
1322 * those sums as well as the little bit more time it takes
1323 * this and each other thread to finish dying after the
1324 * core dump synchronization phase.
1325 */
1326 cputime_to_timeval(cputime_add(p->utime, p->signal->utime),
1327 &prstatus->pr_utime);
1328 cputime_to_timeval(cputime_add(p->stime, p->signal->stime),
1329 &prstatus->pr_stime);
1330 } else {
1331 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1332 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1333 }
1334 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1335 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1336}
1337
1338static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1339 struct mm_struct *mm)
1340{
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -07001341 unsigned int i, len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001342
1343 /* first copy the parameters from user space */
1344 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1345
1346 len = mm->arg_end - mm->arg_start;
1347 if (len >= ELF_PRARGSZ)
1348 len = ELF_PRARGSZ-1;
1349 if (copy_from_user(&psinfo->pr_psargs,
1350 (const char __user *)mm->arg_start, len))
1351 return -EFAULT;
1352 for(i = 0; i < len; i++)
1353 if (psinfo->pr_psargs[i] == 0)
1354 psinfo->pr_psargs[i] = ' ';
1355 psinfo->pr_psargs[len] = 0;
1356
1357 psinfo->pr_pid = p->pid;
1358 psinfo->pr_ppid = p->parent->pid;
1359 psinfo->pr_pgrp = process_group(p);
Cedric Le Goater937949d2006-12-08 02:37:54 -08001360 psinfo->pr_sid = process_session(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001361
1362 i = p->state ? ffz(~p->state) + 1 : 0;
1363 psinfo->pr_state = i;
Carsten Otte55148542006-03-25 03:08:22 -08001364 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001365 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1366 psinfo->pr_nice = task_nice(p);
1367 psinfo->pr_flag = p->flags;
1368 SET_UID(psinfo->pr_uid, p->uid);
1369 SET_GID(psinfo->pr_gid, p->gid);
1370 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1371
1372 return 0;
1373}
1374
1375/* Here is the structure in which status of each thread is captured. */
1376struct elf_thread_status
1377{
1378 struct list_head list;
1379 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1380 elf_fpregset_t fpu; /* NT_PRFPREG */
1381 struct task_struct *thread;
1382#ifdef ELF_CORE_COPY_XFPREGS
1383 elf_fpxregset_t xfpu; /* NT_PRXFPREG */
1384#endif
1385 struct memelfnote notes[3];
1386 int num_notes;
1387};
1388
1389/*
1390 * In order to add the specific thread information for the elf file format,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001391 * we need to keep a linked list of every threads pr_status and then create
1392 * a single section for them in the final core file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001393 */
1394static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1395{
1396 int sz = 0;
1397 struct task_struct *p = t->thread;
1398 t->num_notes = 0;
1399
1400 fill_prstatus(&t->prstatus, p, signr);
1401 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1402
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001403 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1404 &(t->prstatus));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001405 t->num_notes++;
1406 sz += notesize(&t->notes[0]);
1407
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001408 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1409 &t->fpu))) {
1410 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1411 &(t->fpu));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001412 t->num_notes++;
1413 sz += notesize(&t->notes[1]);
1414 }
1415
1416#ifdef ELF_CORE_COPY_XFPREGS
1417 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001418 fill_note(&t->notes[2], "LINUX", NT_PRXFPREG, sizeof(t->xfpu),
1419 &t->xfpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001420 t->num_notes++;
1421 sz += notesize(&t->notes[2]);
1422 }
1423#endif
1424 return sz;
1425}
1426
1427/*
1428 * Actual dumper
1429 *
1430 * This is a two-pass process; first we find the offsets of the bits,
1431 * and then they are actually written out. If we run out of core limit
1432 * we just truncate.
1433 */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001434static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001435{
1436#define NUM_NOTES 6
1437 int has_dumped = 0;
1438 mm_segment_t fs;
1439 int segs;
1440 size_t size = 0;
1441 int i;
1442 struct vm_area_struct *vma;
1443 struct elfhdr *elf = NULL;
Andi Kleend025c9d2006-09-30 23:29:28 -07001444 loff_t offset = 0, dataoff, foffset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001445 unsigned long limit = current->signal->rlim[RLIMIT_CORE].rlim_cur;
1446 int numnote;
1447 struct memelfnote *notes = NULL;
1448 struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */
1449 struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */
1450 struct task_struct *g, *p;
1451 LIST_HEAD(thread_list);
1452 struct list_head *t;
1453 elf_fpregset_t *fpu = NULL;
1454#ifdef ELF_CORE_COPY_XFPREGS
1455 elf_fpxregset_t *xfpu = NULL;
1456#endif
1457 int thread_status_size = 0;
1458 elf_addr_t *auxv;
1459
1460 /*
1461 * We no longer stop all VM operations.
1462 *
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001463 * This is because those proceses that could possibly change map_count
1464 * or the mmap / vma pages are now blocked in do_exit on current
1465 * finishing this core dump.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001466 *
1467 * Only ptrace can touch these memory addresses, but it doesn't change
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001468 * the map_count or the pages allocated. So no possibility of crashing
Linus Torvalds1da177e2005-04-16 15:20:36 -07001469 * exists while dumping the mm->vm_next areas to the core file.
1470 */
1471
1472 /* alloc memory for large data structures: too large to be on stack */
1473 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1474 if (!elf)
1475 goto cleanup;
1476 prstatus = kmalloc(sizeof(*prstatus), GFP_KERNEL);
1477 if (!prstatus)
1478 goto cleanup;
1479 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1480 if (!psinfo)
1481 goto cleanup;
1482 notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote), GFP_KERNEL);
1483 if (!notes)
1484 goto cleanup;
1485 fpu = kmalloc(sizeof(*fpu), GFP_KERNEL);
1486 if (!fpu)
1487 goto cleanup;
1488#ifdef ELF_CORE_COPY_XFPREGS
1489 xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL);
1490 if (!xfpu)
1491 goto cleanup;
1492#endif
1493
1494 if (signr) {
1495 struct elf_thread_status *tmp;
Oleg Nesterov486ccb02006-09-29 02:00:24 -07001496 rcu_read_lock();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001497 do_each_thread(g,p)
1498 if (current->mm == p->mm && current != p) {
Oliver Neukum11b0b5a2006-03-25 03:08:13 -08001499 tmp = kzalloc(sizeof(*tmp), GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001500 if (!tmp) {
Oleg Nesterov486ccb02006-09-29 02:00:24 -07001501 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001502 goto cleanup;
1503 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504 tmp->thread = p;
1505 list_add(&tmp->list, &thread_list);
1506 }
1507 while_each_thread(g,p);
Oleg Nesterov486ccb02006-09-29 02:00:24 -07001508 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001509 list_for_each(t, &thread_list) {
1510 struct elf_thread_status *tmp;
1511 int sz;
1512
1513 tmp = list_entry(t, struct elf_thread_status, list);
1514 sz = elf_dump_thread_status(signr, tmp);
1515 thread_status_size += sz;
1516 }
1517 }
1518 /* now collect the dump for the current */
1519 memset(prstatus, 0, sizeof(*prstatus));
1520 fill_prstatus(prstatus, current, signr);
1521 elf_core_copy_regs(&prstatus->pr_reg, regs);
1522
1523 segs = current->mm->map_count;
1524#ifdef ELF_CORE_EXTRA_PHDRS
1525 segs += ELF_CORE_EXTRA_PHDRS;
1526#endif
1527
1528 /* Set up header */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001529 fill_elf_header(elf, segs + 1); /* including notes section */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530
1531 has_dumped = 1;
1532 current->flags |= PF_DUMPCORE;
1533
1534 /*
1535 * Set up the notes in similar form to SVR4 core dumps made
1536 * with info from their /proc.
1537 */
1538
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001539 fill_note(notes + 0, "CORE", NT_PRSTATUS, sizeof(*prstatus), prstatus);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001540 fill_psinfo(psinfo, current->group_leader, current->mm);
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001541 fill_note(notes + 1, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001542
Eric W. Biedermana9289722005-10-30 15:02:08 -08001543 numnote = 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001545 auxv = (elf_addr_t *)current->mm->saved_auxv;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001546
1547 i = 0;
1548 do
1549 i += 2;
1550 while (auxv[i - 2] != AT_NULL);
1551 fill_note(&notes[numnote++], "CORE", NT_AUXV,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001552 i * sizeof(elf_addr_t), auxv);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001553
1554 /* Try to dump the FPU. */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001555 if ((prstatus->pr_fpvalid =
1556 elf_core_copy_task_fpregs(current, regs, fpu)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001557 fill_note(notes + numnote++,
1558 "CORE", NT_PRFPREG, sizeof(*fpu), fpu);
1559#ifdef ELF_CORE_COPY_XFPREGS
1560 if (elf_core_copy_task_xfpregs(current, xfpu))
1561 fill_note(notes + numnote++,
1562 "LINUX", NT_PRXFPREG, sizeof(*xfpu), xfpu);
1563#endif
1564
1565 fs = get_fs();
1566 set_fs(KERNEL_DS);
1567
1568 DUMP_WRITE(elf, sizeof(*elf));
1569 offset += sizeof(*elf); /* Elf header */
Petr Vandroveca7a0d862006-10-13 18:42:07 +02001570 offset += (segs + 1) * sizeof(struct elf_phdr); /* Program headers */
1571 foffset = offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001572
1573 /* Write notes phdr entry */
1574 {
1575 struct elf_phdr phdr;
1576 int sz = 0;
1577
1578 for (i = 0; i < numnote; i++)
1579 sz += notesize(notes + i);
1580
1581 sz += thread_status_size;
1582
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01001583#ifdef ELF_CORE_WRITE_EXTRA_NOTES
1584 sz += ELF_CORE_EXTRA_NOTES_SIZE;
1585#endif
1586
Linus Torvalds1da177e2005-04-16 15:20:36 -07001587 fill_elf_note_phdr(&phdr, sz, offset);
1588 offset += sz;
1589 DUMP_WRITE(&phdr, sizeof(phdr));
1590 }
1591
Linus Torvalds1da177e2005-04-16 15:20:36 -07001592 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1593
1594 /* Write program headers for segments dump */
1595 for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
1596 struct elf_phdr phdr;
1597 size_t sz;
1598
1599 sz = vma->vm_end - vma->vm_start;
1600
1601 phdr.p_type = PT_LOAD;
1602 phdr.p_offset = offset;
1603 phdr.p_vaddr = vma->vm_start;
1604 phdr.p_paddr = 0;
1605 phdr.p_filesz = maydump(vma) ? sz : 0;
1606 phdr.p_memsz = sz;
1607 offset += phdr.p_filesz;
1608 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001609 if (vma->vm_flags & VM_WRITE)
1610 phdr.p_flags |= PF_W;
1611 if (vma->vm_flags & VM_EXEC)
1612 phdr.p_flags |= PF_X;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001613 phdr.p_align = ELF_EXEC_PAGESIZE;
1614
1615 DUMP_WRITE(&phdr, sizeof(phdr));
1616 }
1617
1618#ifdef ELF_CORE_WRITE_EXTRA_PHDRS
1619 ELF_CORE_WRITE_EXTRA_PHDRS;
1620#endif
1621
1622 /* write out the notes section */
1623 for (i = 0; i < numnote; i++)
Andi Kleend025c9d2006-09-30 23:29:28 -07001624 if (!writenote(notes + i, file, &foffset))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001625 goto end_coredump;
1626
Dwayne Grant McConnellbf1ab972006-11-23 00:46:37 +01001627#ifdef ELF_CORE_WRITE_EXTRA_NOTES
1628 ELF_CORE_WRITE_EXTRA_NOTES;
1629#endif
1630
Linus Torvalds1da177e2005-04-16 15:20:36 -07001631 /* write out the thread status notes section */
1632 list_for_each(t, &thread_list) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001633 struct elf_thread_status *tmp =
1634 list_entry(t, struct elf_thread_status, list);
1635
Linus Torvalds1da177e2005-04-16 15:20:36 -07001636 for (i = 0; i < tmp->num_notes; i++)
Andi Kleend025c9d2006-09-30 23:29:28 -07001637 if (!writenote(&tmp->notes[i], file, &foffset))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001638 goto end_coredump;
1639 }
Andi Kleend025c9d2006-09-30 23:29:28 -07001640
1641 /* Align to page */
1642 DUMP_SEEK(dataoff - foffset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001643
1644 for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
1645 unsigned long addr;
1646
1647 if (!maydump(vma))
1648 continue;
1649
1650 for (addr = vma->vm_start;
1651 addr < vma->vm_end;
1652 addr += PAGE_SIZE) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001653 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001654 struct vm_area_struct *vma;
1655
1656 if (get_user_pages(current, current->mm, addr, 1, 0, 1,
1657 &page, &vma) <= 0) {
Andi Kleend025c9d2006-09-30 23:29:28 -07001658 DUMP_SEEK(PAGE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001659 } else {
1660 if (page == ZERO_PAGE(addr)) {
Andi Kleend025c9d2006-09-30 23:29:28 -07001661 DUMP_SEEK(PAGE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001662 } else {
1663 void *kaddr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001664 flush_cache_page(vma, addr,
1665 page_to_pfn(page));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666 kaddr = kmap(page);
1667 if ((size += PAGE_SIZE) > limit ||
1668 !dump_write(file, kaddr,
1669 PAGE_SIZE)) {
1670 kunmap(page);
1671 page_cache_release(page);
1672 goto end_coredump;
1673 }
1674 kunmap(page);
1675 }
1676 page_cache_release(page);
1677 }
1678 }
1679 }
1680
1681#ifdef ELF_CORE_WRITE_EXTRA_DATA
1682 ELF_CORE_WRITE_EXTRA_DATA;
1683#endif
1684
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685end_coredump:
1686 set_fs(fs);
1687
1688cleanup:
Jesper Juhl74da6cd2006-01-11 01:51:26 +01001689 while (!list_empty(&thread_list)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001690 struct list_head *tmp = thread_list.next;
1691 list_del(tmp);
1692 kfree(list_entry(tmp, struct elf_thread_status, list));
1693 }
1694
1695 kfree(elf);
1696 kfree(prstatus);
1697 kfree(psinfo);
1698 kfree(notes);
1699 kfree(fpu);
1700#ifdef ELF_CORE_COPY_XFPREGS
1701 kfree(xfpu);
1702#endif
1703 return has_dumped;
1704#undef NUM_NOTES
1705}
1706
1707#endif /* USE_ELF_CORE_DUMP */
1708
1709static int __init init_elf_binfmt(void)
1710{
1711 return register_binfmt(&elf_format);
1712}
1713
1714static void __exit exit_elf_binfmt(void)
1715{
1716 /* Remove the COFF and ELF loaders. */
1717 unregister_binfmt(&elf_format);
1718}
1719
1720core_initcall(init_elf_binfmt);
1721module_exit(exit_elf_binfmt);
1722MODULE_LICENSE("GPL");