blob: 672a3b90bc556628874d5ab1494b654dc486a74b [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);
49extern int dump_fpu (struct pt_regs *, elf_fpregset_t *);
50
51#ifndef elf_addr_t
52#define elf_addr_t unsigned long
53#endif
54
55/*
56 * If we don't support core dumping, then supply a NULL so we
57 * don't even try.
58 */
Matt Mackall708e9a72006-01-08 01:05:25 -080059#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070060static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file);
Linus Torvalds1da177e2005-04-16 15:20:36 -070061#else
62#define elf_core_dump NULL
63#endif
64
65#if ELF_EXEC_PAGESIZE > PAGE_SIZE
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070066#define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
Linus Torvalds1da177e2005-04-16 15:20:36 -070067#else
Jesper Juhlf4e5cc22006-06-23 02:05:35 -070068#define ELF_MIN_ALIGN PAGE_SIZE
Linus Torvalds1da177e2005-04-16 15:20:36 -070069#endif
70
71#ifndef ELF_CORE_EFLAGS
72#define ELF_CORE_EFLAGS 0
73#endif
74
75#define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
76#define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
77#define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
78
79static struct linux_binfmt elf_format = {
80 .module = THIS_MODULE,
81 .load_binary = load_elf_binary,
82 .load_shlib = load_elf_library,
83 .core_dump = elf_core_dump,
84 .min_coredump = ELF_EXEC_PAGESIZE
85};
86
Chuck Ebbertce510592006-07-03 00:24:14 -070087#define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
Linus Torvalds1da177e2005-04-16 15:20:36 -070088
89static int set_brk(unsigned long start, unsigned long end)
90{
91 start = ELF_PAGEALIGN(start);
92 end = ELF_PAGEALIGN(end);
93 if (end > start) {
94 unsigned long addr;
95 down_write(&current->mm->mmap_sem);
96 addr = do_brk(start, end - start);
97 up_write(&current->mm->mmap_sem);
98 if (BAD_ADDR(addr))
99 return addr;
100 }
101 current->mm->start_brk = current->mm->brk = end;
102 return 0;
103}
104
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105/* We need to explicitly zero any fractional pages
106 after the data section (i.e. bss). This would
107 contain the junk from the file that should not
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700108 be in memory
109 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110static int padzero(unsigned long elf_bss)
111{
112 unsigned long nbyte;
113
114 nbyte = ELF_PAGEOFFSET(elf_bss);
115 if (nbyte) {
116 nbyte = ELF_MIN_ALIGN - nbyte;
117 if (clear_user((void __user *) elf_bss, nbyte))
118 return -EFAULT;
119 }
120 return 0;
121}
122
123/* Let's use some macros to make this stack manipulation a litle clearer */
124#ifdef CONFIG_STACK_GROWSUP
125#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
126#define STACK_ROUND(sp, items) \
127 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700128#define STACK_ALLOC(sp, len) ({ \
129 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
130 old_sp; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131#else
132#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
133#define STACK_ROUND(sp, items) \
134 (((unsigned long) (sp - items)) &~ 15UL)
135#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
136#endif
137
138static int
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700139create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 int interp_aout, unsigned long load_addr,
141 unsigned long interp_load_addr)
142{
143 unsigned long p = bprm->p;
144 int argc = bprm->argc;
145 int envc = bprm->envc;
146 elf_addr_t __user *argv;
147 elf_addr_t __user *envp;
148 elf_addr_t __user *sp;
149 elf_addr_t __user *u_platform;
150 const char *k_platform = ELF_PLATFORM;
151 int items;
152 elf_addr_t *elf_info;
153 int ei_index = 0;
154 struct task_struct *tsk = current;
155
156 /*
157 * If this architecture has a platform capability string, copy it
158 * to userspace. In some cases (Sparc), this info is impossible
159 * for userspace to get any other way, in others (i386) it is
160 * merely difficult.
161 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 u_platform = NULL;
163 if (k_platform) {
164 size_t len = strlen(k_platform) + 1;
165
166 /*
167 * In some cases (e.g. Hyper-Threading), we want to avoid L1
168 * evictions by the processes running on the same package. One
169 * thing we can do is to shuffle the initial stack for them.
170 */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700171
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 p = arch_align_stack(p);
173
174 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
175 if (__copy_to_user(u_platform, k_platform, len))
176 return -EFAULT;
177 }
178
179 /* Create the ELF interpreter info */
Jesper Juhl785d5572006-06-23 02:05:35 -0700180 elf_info = (elf_addr_t *)current->mm->saved_auxv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181#define NEW_AUX_ENT(id, val) \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700182 do { \
Jesper Juhl785d5572006-06-23 02:05:35 -0700183 elf_info[ei_index++] = id; \
184 elf_info[ei_index++] = val; \
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700185 } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186
187#ifdef ARCH_DLINFO
188 /*
189 * ARCH_DLINFO must come first so PPC can do its special alignment of
190 * AUXV.
191 */
192 ARCH_DLINFO;
193#endif
194 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
195 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
196 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
197 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700198 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
200 NEW_AUX_ENT(AT_BASE, interp_load_addr);
201 NEW_AUX_ENT(AT_FLAGS, 0);
202 NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
Jesper Juhl785d5572006-06-23 02:05:35 -0700203 NEW_AUX_ENT(AT_UID, tsk->uid);
204 NEW_AUX_ENT(AT_EUID, tsk->euid);
205 NEW_AUX_ENT(AT_GID, tsk->gid);
206 NEW_AUX_ENT(AT_EGID, tsk->egid);
207 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 if (k_platform) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700209 NEW_AUX_ENT(AT_PLATFORM,
Jesper Juhl785d5572006-06-23 02:05:35 -0700210 (elf_addr_t)(unsigned long)u_platform);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 }
212 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
Jesper Juhl785d5572006-06-23 02:05:35 -0700213 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214 }
215#undef NEW_AUX_ENT
216 /* AT_NULL is zero; clear the rest too */
217 memset(&elf_info[ei_index], 0,
218 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
219
220 /* And advance past the AT_NULL entry. */
221 ei_index += 2;
222
223 sp = STACK_ADD(p, ei_index);
224
225 items = (argc + 1) + (envc + 1);
226 if (interp_aout) {
227 items += 3; /* a.out interpreters require argv & envp too */
228 } else {
229 items += 1; /* ELF interpreters only put argc on the stack */
230 }
231 bprm->p = STACK_ROUND(sp, items);
232
233 /* Point sp at the lowest address on the stack */
234#ifdef CONFIG_STACK_GROWSUP
235 sp = (elf_addr_t __user *)bprm->p - items - ei_index;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700236 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237#else
238 sp = (elf_addr_t __user *)bprm->p;
239#endif
240
241 /* Now, let's put argc (and argv, envp if appropriate) on the stack */
242 if (__put_user(argc, sp++))
243 return -EFAULT;
244 if (interp_aout) {
245 argv = sp + 2;
246 envp = argv + argc + 1;
247 __put_user((elf_addr_t)(unsigned long)argv, sp++);
248 __put_user((elf_addr_t)(unsigned long)envp, sp++);
249 } else {
250 argv = sp;
251 envp = argv + argc + 1;
252 }
253
254 /* Populate argv and envp */
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -0700255 p = current->mm->arg_end = current->mm->arg_start;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 while (argc-- > 0) {
257 size_t len;
258 __put_user((elf_addr_t)p, argv++);
259 len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
260 if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
261 return 0;
262 p += len;
263 }
264 if (__put_user(0, argv))
265 return -EFAULT;
266 current->mm->arg_end = current->mm->env_start = p;
267 while (envc-- > 0) {
268 size_t len;
269 __put_user((elf_addr_t)p, envp++);
270 len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
271 if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
272 return 0;
273 p += len;
274 }
275 if (__put_user(0, envp))
276 return -EFAULT;
277 current->mm->env_end = p;
278
279 /* Put the elf_info on the stack in the right place. */
280 sp = (elf_addr_t __user *)envp + 1;
281 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
282 return -EFAULT;
283 return 0;
284}
285
286#ifndef elf_map
287
288static unsigned long elf_map(struct file *filep, unsigned long addr,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700289 struct elf_phdr *eppnt, int prot, int type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290{
291 unsigned long map_addr;
David Gibsondda6ebd2006-01-08 01:03:35 -0800292 unsigned long pageoffset = ELF_PAGEOFFSET(eppnt->p_vaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293
294 down_write(&current->mm->mmap_sem);
David Gibsondda6ebd2006-01-08 01:03:35 -0800295 /* mmap() will return -EINVAL if given a zero size, but a
296 * segment with zero filesize is perfectly valid */
297 if (eppnt->p_filesz + pageoffset)
298 map_addr = do_mmap(filep, ELF_PAGESTART(addr),
299 eppnt->p_filesz + pageoffset, prot, type,
300 eppnt->p_offset - pageoffset);
301 else
302 map_addr = ELF_PAGESTART(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 up_write(&current->mm->mmap_sem);
304 return(map_addr);
305}
306
307#endif /* !elf_map */
308
309/* This is much more generalized than the library routine read function,
310 so we keep this separate. Technically the library read function
311 is only provided so that we can read a.out libraries that have
312 an ELF header */
313
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700314static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
315 struct file *interpreter, unsigned long *interp_load_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316{
317 struct elf_phdr *elf_phdata;
318 struct elf_phdr *eppnt;
319 unsigned long load_addr = 0;
320 int load_addr_set = 0;
321 unsigned long last_bss = 0, elf_bss = 0;
322 unsigned long error = ~0UL;
323 int retval, i, size;
324
325 /* First of all, some simple consistency checks */
326 if (interp_elf_ex->e_type != ET_EXEC &&
327 interp_elf_ex->e_type != ET_DYN)
328 goto out;
329 if (!elf_check_arch(interp_elf_ex))
330 goto out;
331 if (!interpreter->f_op || !interpreter->f_op->mmap)
332 goto out;
333
334 /*
335 * If the size of this structure has changed, then punt, since
336 * we will be doing the wrong thing.
337 */
338 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
339 goto out;
340 if (interp_elf_ex->e_phnum < 1 ||
341 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
342 goto out;
343
344 /* Now read in all of the header information */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
346 if (size > ELF_MIN_ALIGN)
347 goto out;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700348 elf_phdata = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349 if (!elf_phdata)
350 goto out;
351
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700352 retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
353 (char *)elf_phdata,size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 error = -EIO;
355 if (retval != size) {
356 if (retval < 0)
357 error = retval;
358 goto out_close;
359 }
360
361 eppnt = elf_phdata;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700362 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
363 if (eppnt->p_type == PT_LOAD) {
364 int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
365 int elf_prot = 0;
366 unsigned long vaddr = 0;
367 unsigned long k, map_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700369 if (eppnt->p_flags & PF_R)
370 elf_prot = PROT_READ;
371 if (eppnt->p_flags & PF_W)
372 elf_prot |= PROT_WRITE;
373 if (eppnt->p_flags & PF_X)
374 elf_prot |= PROT_EXEC;
375 vaddr = eppnt->p_vaddr;
376 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
377 elf_type |= MAP_FIXED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700379 map_addr = elf_map(interpreter, load_addr + vaddr,
380 eppnt, elf_prot, elf_type);
381 error = map_addr;
382 if (BAD_ADDR(map_addr))
383 goto out_close;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700385 if (!load_addr_set &&
386 interp_elf_ex->e_type == ET_DYN) {
387 load_addr = map_addr - ELF_PAGESTART(vaddr);
388 load_addr_set = 1;
389 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700391 /*
392 * Check to see if the section's size will overflow the
393 * allowed task size. Note that p_filesz must always be
394 * <= p_memsize so it's only necessary to check p_memsz.
395 */
396 k = load_addr + eppnt->p_vaddr;
Chuck Ebbertce510592006-07-03 00:24:14 -0700397 if (BAD_ADDR(k) ||
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700398 eppnt->p_filesz > eppnt->p_memsz ||
399 eppnt->p_memsz > TASK_SIZE ||
400 TASK_SIZE - eppnt->p_memsz < k) {
401 error = -ENOMEM;
402 goto out_close;
403 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700405 /*
406 * Find the end of the file mapping for this phdr, and
407 * keep track of the largest address we see for this.
408 */
409 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
410 if (k > elf_bss)
411 elf_bss = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700413 /*
414 * Do the same thing for the memory mapping - between
415 * elf_bss and last_bss is the bss section.
416 */
417 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
418 if (k > last_bss)
419 last_bss = k;
420 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421 }
422
423 /*
424 * Now fill out the bss section. First pad the last page up
425 * to the page boundary, and then perform a mmap to make sure
426 * that there are zero-mapped pages up to and including the
427 * last bss page.
428 */
429 if (padzero(elf_bss)) {
430 error = -EFAULT;
431 goto out_close;
432 }
433
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700434 /* What we have mapped so far */
435 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436
437 /* Map the last of the bss segment */
438 if (last_bss > elf_bss) {
439 down_write(&current->mm->mmap_sem);
440 error = do_brk(elf_bss, last_bss - elf_bss);
441 up_write(&current->mm->mmap_sem);
442 if (BAD_ADDR(error))
443 goto out_close;
444 }
445
446 *interp_load_addr = load_addr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700447 error = ((unsigned long)interp_elf_ex->e_entry) + load_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448
449out_close:
450 kfree(elf_phdata);
451out:
452 return error;
453}
454
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700455static unsigned long load_aout_interp(struct exec *interp_ex,
456 struct file *interpreter)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457{
458 unsigned long text_data, elf_entry = ~0UL;
459 char __user * addr;
460 loff_t offset;
461
462 current->mm->end_code = interp_ex->a_text;
463 text_data = interp_ex->a_text + interp_ex->a_data;
464 current->mm->end_data = text_data;
465 current->mm->brk = interp_ex->a_bss + text_data;
466
467 switch (N_MAGIC(*interp_ex)) {
468 case OMAGIC:
469 offset = 32;
470 addr = (char __user *)0;
471 break;
472 case ZMAGIC:
473 case QMAGIC:
474 offset = N_TXTOFF(*interp_ex);
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700475 addr = (char __user *)N_TXTADDR(*interp_ex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 break;
477 default:
478 goto out;
479 }
480
481 down_write(&current->mm->mmap_sem);
482 do_brk(0, text_data);
483 up_write(&current->mm->mmap_sem);
484 if (!interpreter->f_op || !interpreter->f_op->read)
485 goto out;
486 if (interpreter->f_op->read(interpreter, addr, text_data, &offset) < 0)
487 goto out;
488 flush_icache_range((unsigned long)addr,
489 (unsigned long)addr + text_data);
490
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 down_write(&current->mm->mmap_sem);
492 do_brk(ELF_PAGESTART(text_data + ELF_MIN_ALIGN - 1),
493 interp_ex->a_bss);
494 up_write(&current->mm->mmap_sem);
495 elf_entry = interp_ex->a_entry;
496
497out:
498 return elf_entry;
499}
500
501/*
502 * These are the functions used to load ELF style executables and shared
503 * libraries. There is no binary dependent code anywhere else.
504 */
505
506#define INTERPRETER_NONE 0
507#define INTERPRETER_AOUT 1
508#define INTERPRETER_ELF 2
509
Andi Kleen913bd902006-03-25 16:29:09 +0100510#ifndef STACK_RND_MASK
511#define STACK_RND_MASK 0x7ff /* with 4K pages 8MB of VA */
512#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513
514static unsigned long randomize_stack_top(unsigned long stack_top)
515{
516 unsigned int random_variable = 0;
517
Andi Kleen913bd902006-03-25 16:29:09 +0100518 if (current->flags & PF_RANDOMIZE) {
519 random_variable = get_random_int() & STACK_RND_MASK;
520 random_variable <<= PAGE_SHIFT;
521 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522#ifdef CONFIG_STACK_GROWSUP
Andi Kleen913bd902006-03-25 16:29:09 +0100523 return PAGE_ALIGN(stack_top) + random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524#else
Andi Kleen913bd902006-03-25 16:29:09 +0100525 return PAGE_ALIGN(stack_top) - random_variable;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526#endif
527}
528
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700529static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530{
531 struct file *interpreter = NULL; /* to shut gcc up */
532 unsigned long load_addr = 0, load_bias = 0;
533 int load_addr_set = 0;
534 char * elf_interpreter = NULL;
535 unsigned int interpreter_type = INTERPRETER_NONE;
536 unsigned char ibcs2_interpreter = 0;
537 unsigned long error;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700538 struct elf_phdr *elf_ppnt, *elf_phdata;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 unsigned long elf_bss, elf_brk;
540 int elf_exec_fileno;
541 int retval, i;
542 unsigned int size;
543 unsigned long elf_entry, interp_load_addr = 0;
544 unsigned long start_code, end_code, start_data, end_data;
545 unsigned long reloc_func_desc = 0;
546 char passed_fileno[6];
547 struct files_struct *files;
548 int have_pt_gnu_stack, executable_stack = EXSTACK_DEFAULT;
549 unsigned long def_flags = 0;
550 struct {
551 struct elfhdr elf_ex;
552 struct elfhdr interp_elf_ex;
553 struct exec interp_ex;
554 } *loc;
555
556 loc = kmalloc(sizeof(*loc), GFP_KERNEL);
557 if (!loc) {
558 retval = -ENOMEM;
559 goto out_ret;
560 }
561
562 /* Get the exec-header */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700563 loc->elf_ex = *((struct elfhdr *)bprm->buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564
565 retval = -ENOEXEC;
566 /* First of all, some simple consistency checks */
567 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
568 goto out;
569
570 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
571 goto out;
572 if (!elf_check_arch(&loc->elf_ex))
573 goto out;
574 if (!bprm->file->f_op||!bprm->file->f_op->mmap)
575 goto out;
576
577 /* Now read in all of the header information */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr))
579 goto out;
580 if (loc->elf_ex.e_phnum < 1 ||
581 loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr))
582 goto out;
583 size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr);
584 retval = -ENOMEM;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700585 elf_phdata = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 if (!elf_phdata)
587 goto out;
588
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700589 retval = kernel_read(bprm->file, loc->elf_ex.e_phoff,
590 (char *)elf_phdata, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 if (retval != size) {
592 if (retval >= 0)
593 retval = -EIO;
594 goto out_free_ph;
595 }
596
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700597 files = current->files; /* Refcounted so ok */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 retval = unshare_files();
599 if (retval < 0)
600 goto out_free_ph;
601 if (files == current->files) {
602 put_files_struct(files);
603 files = NULL;
604 }
605
606 /* exec will make our files private anyway, but for the a.out
607 loader stuff we need to do it earlier */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608 retval = get_unused_fd();
609 if (retval < 0)
610 goto out_free_fh;
611 get_file(bprm->file);
612 fd_install(elf_exec_fileno = retval, bprm->file);
613
614 elf_ppnt = elf_phdata;
615 elf_bss = 0;
616 elf_brk = 0;
617
618 start_code = ~0UL;
619 end_code = 0;
620 start_data = 0;
621 end_data = 0;
622
623 for (i = 0; i < loc->elf_ex.e_phnum; i++) {
624 if (elf_ppnt->p_type == PT_INTERP) {
625 /* This is the program interpreter used for
626 * shared libraries - for now assume that this
627 * is an a.out format binary
628 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 retval = -ENOEXEC;
630 if (elf_ppnt->p_filesz > PATH_MAX ||
631 elf_ppnt->p_filesz < 2)
632 goto out_free_file;
633
634 retval = -ENOMEM;
Jesper Juhl792db3a2006-01-09 20:54:45 -0800635 elf_interpreter = kmalloc(elf_ppnt->p_filesz,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700636 GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 if (!elf_interpreter)
638 goto out_free_file;
639
640 retval = kernel_read(bprm->file, elf_ppnt->p_offset,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700641 elf_interpreter,
642 elf_ppnt->p_filesz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 if (retval != elf_ppnt->p_filesz) {
644 if (retval >= 0)
645 retval = -EIO;
646 goto out_free_interp;
647 }
648 /* make sure path is NULL terminated */
649 retval = -ENOEXEC;
650 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
651 goto out_free_interp;
652
653 /* If the program interpreter is one of these two,
654 * then assume an iBCS2 image. Otherwise assume
655 * a native linux image.
656 */
657 if (strcmp(elf_interpreter,"/usr/lib/libc.so.1") == 0 ||
658 strcmp(elf_interpreter,"/usr/lib/ld.so.1") == 0)
659 ibcs2_interpreter = 1;
660
661 /*
662 * The early SET_PERSONALITY here is so that the lookup
663 * for the interpreter happens in the namespace of the
664 * to-be-execed image. SET_PERSONALITY can select an
665 * alternate root.
666 *
667 * However, SET_PERSONALITY is NOT allowed to switch
668 * this task into the new images's memory mapping
669 * policy - that is, TASK_SIZE must still evaluate to
670 * that which is appropriate to the execing application.
671 * This is because exit_mmap() needs to have TASK_SIZE
672 * evaluate to the size of the old image.
673 *
674 * So if (say) a 64-bit application is execing a 32-bit
675 * application it is the architecture's responsibility
676 * to defer changing the value of TASK_SIZE until the
677 * switch really is going to happen - do this in
678 * flush_thread(). - akpm
679 */
680 SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter);
681
682 interpreter = open_exec(elf_interpreter);
683 retval = PTR_ERR(interpreter);
684 if (IS_ERR(interpreter))
685 goto out_free_interp;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700686 retval = kernel_read(interpreter, 0, bprm->buf,
687 BINPRM_BUF_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 if (retval != BINPRM_BUF_SIZE) {
689 if (retval >= 0)
690 retval = -EIO;
691 goto out_free_dentry;
692 }
693
694 /* Get the exec headers */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700695 loc->interp_ex = *((struct exec *)bprm->buf);
696 loc->interp_elf_ex = *((struct elfhdr *)bprm->buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 break;
698 }
699 elf_ppnt++;
700 }
701
702 elf_ppnt = elf_phdata;
703 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
704 if (elf_ppnt->p_type == PT_GNU_STACK) {
705 if (elf_ppnt->p_flags & PF_X)
706 executable_stack = EXSTACK_ENABLE_X;
707 else
708 executable_stack = EXSTACK_DISABLE_X;
709 break;
710 }
711 have_pt_gnu_stack = (i < loc->elf_ex.e_phnum);
712
713 /* Some simple consistency checks for the interpreter */
714 if (elf_interpreter) {
715 interpreter_type = INTERPRETER_ELF | INTERPRETER_AOUT;
716
717 /* Now figure out which format our binary is */
718 if ((N_MAGIC(loc->interp_ex) != OMAGIC) &&
719 (N_MAGIC(loc->interp_ex) != ZMAGIC) &&
720 (N_MAGIC(loc->interp_ex) != QMAGIC))
721 interpreter_type = INTERPRETER_ELF;
722
723 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
724 interpreter_type &= ~INTERPRETER_ELF;
725
726 retval = -ELIBBAD;
727 if (!interpreter_type)
728 goto out_free_dentry;
729
730 /* Make sure only one type was selected */
731 if ((interpreter_type & INTERPRETER_ELF) &&
732 interpreter_type != INTERPRETER_ELF) {
733 // FIXME - ratelimit this before re-enabling
734 // printk(KERN_WARNING "ELF: Ambiguous type, using ELF\n");
735 interpreter_type = INTERPRETER_ELF;
736 }
737 /* Verify the interpreter has a valid arch */
738 if ((interpreter_type == INTERPRETER_ELF) &&
739 !elf_check_arch(&loc->interp_elf_ex))
740 goto out_free_dentry;
741 } else {
742 /* Executables without an interpreter also need a personality */
743 SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter);
744 }
745
746 /* OK, we are done with that, now set up the arg stuff,
747 and then start this sucker up */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 if ((!bprm->sh_bang) && (interpreter_type == INTERPRETER_AOUT)) {
749 char *passed_p = passed_fileno;
750 sprintf(passed_fileno, "%d", elf_exec_fileno);
751
752 if (elf_interpreter) {
753 retval = copy_strings_kernel(1, &passed_p, bprm);
754 if (retval)
755 goto out_free_dentry;
756 bprm->argc++;
757 }
758 }
759
760 /* Flush all traces of the currently running executable */
761 retval = flush_old_exec(bprm);
762 if (retval)
763 goto out_free_dentry;
764
765 /* Discard our unneeded old files struct */
766 if (files) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767 put_files_struct(files);
768 files = NULL;
769 }
770
771 /* OK, This is the point of no return */
772 current->mm->start_data = 0;
773 current->mm->end_data = 0;
774 current->mm->end_code = 0;
775 current->mm->mmap = NULL;
776 current->flags &= ~PF_FORKNOEXEC;
777 current->mm->def_flags = def_flags;
778
779 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
780 may depend on the personality. */
781 SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter);
782 if (elf_read_implies_exec(loc->elf_ex, executable_stack))
783 current->personality |= READ_IMPLIES_EXEC;
784
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700785 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786 current->flags |= PF_RANDOMIZE;
787 arch_pick_mmap_layout(current->mm);
788
789 /* Do this so that we can load the interpreter, if need be. We will
790 change some of these later */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791 current->mm->free_area_cache = current->mm->mmap_base;
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700792 current->mm->cached_hole_size = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
794 executable_stack);
795 if (retval < 0) {
796 send_sig(SIGKILL, current, 0);
797 goto out_free_dentry;
798 }
799
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 current->mm->start_stack = bprm->p;
801
802 /* Now we do a little grungy work by mmaping the ELF image into
803 the correct location in memory. At this point, we assume that
804 the image should be loaded at fixed address, not at a variable
805 address. */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700806 for(i = 0, elf_ppnt = elf_phdata;
807 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 int elf_prot = 0, elf_flags;
809 unsigned long k, vaddr;
810
811 if (elf_ppnt->p_type != PT_LOAD)
812 continue;
813
814 if (unlikely (elf_brk > elf_bss)) {
815 unsigned long nbyte;
816
817 /* There was a PT_LOAD segment with p_memsz > p_filesz
818 before this one. Map anonymous pages, if needed,
819 and clear the area. */
820 retval = set_brk (elf_bss + load_bias,
821 elf_brk + load_bias);
822 if (retval) {
823 send_sig(SIGKILL, current, 0);
824 goto out_free_dentry;
825 }
826 nbyte = ELF_PAGEOFFSET(elf_bss);
827 if (nbyte) {
828 nbyte = ELF_MIN_ALIGN - nbyte;
829 if (nbyte > elf_brk - elf_bss)
830 nbyte = elf_brk - elf_bss;
831 if (clear_user((void __user *)elf_bss +
832 load_bias, nbyte)) {
833 /*
834 * This bss-zeroing can fail if the ELF
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700835 * file specifies odd protections. So
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836 * we don't check the return value
837 */
838 }
839 }
840 }
841
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700842 if (elf_ppnt->p_flags & PF_R)
843 elf_prot |= PROT_READ;
844 if (elf_ppnt->p_flags & PF_W)
845 elf_prot |= PROT_WRITE;
846 if (elf_ppnt->p_flags & PF_X)
847 elf_prot |= PROT_EXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700849 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850
851 vaddr = elf_ppnt->p_vaddr;
852 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
853 elf_flags |= MAP_FIXED;
854 } else if (loc->elf_ex.e_type == ET_DYN) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700855 /* Try and get dynamic programs out of the way of the
856 * default mmap base, as well as whatever program they
857 * might try to exec. This is because the brk will
858 * follow the loader, and is not movable. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
860 }
861
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700862 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
863 elf_prot, elf_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864 if (BAD_ADDR(error)) {
865 send_sig(SIGKILL, current, 0);
866 goto out_free_dentry;
867 }
868
869 if (!load_addr_set) {
870 load_addr_set = 1;
871 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
872 if (loc->elf_ex.e_type == ET_DYN) {
873 load_bias += error -
874 ELF_PAGESTART(load_bias + vaddr);
875 load_addr += load_bias;
876 reloc_func_desc = load_bias;
877 }
878 }
879 k = elf_ppnt->p_vaddr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700880 if (k < start_code)
881 start_code = k;
882 if (start_data < k)
883 start_data = k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884
885 /*
886 * Check to see if the section's size will overflow the
887 * allowed task size. Note that p_filesz must always be
888 * <= p_memsz so it is only necessary to check p_memsz.
889 */
Chuck Ebbertce510592006-07-03 00:24:14 -0700890 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700891 elf_ppnt->p_memsz > TASK_SIZE ||
892 TASK_SIZE - elf_ppnt->p_memsz < k) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700893 /* set_brk can never work. Avoid overflows. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894 send_sig(SIGKILL, current, 0);
895 goto out_free_dentry;
896 }
897
898 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
899
900 if (k > elf_bss)
901 elf_bss = k;
902 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
903 end_code = k;
904 if (end_data < k)
905 end_data = k;
906 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
907 if (k > elf_brk)
908 elf_brk = k;
909 }
910
911 loc->elf_ex.e_entry += load_bias;
912 elf_bss += load_bias;
913 elf_brk += load_bias;
914 start_code += load_bias;
915 end_code += load_bias;
916 start_data += load_bias;
917 end_data += load_bias;
918
919 /* Calling set_brk effectively mmaps the pages that we need
920 * for the bss and break sections. We must do this before
921 * mapping in the interpreter, to make sure it doesn't wind
922 * up getting placed where the bss needs to go.
923 */
924 retval = set_brk(elf_bss, elf_brk);
925 if (retval) {
926 send_sig(SIGKILL, current, 0);
927 goto out_free_dentry;
928 }
akpm@osdl.org6de50512005-10-11 08:29:08 -0700929 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930 send_sig(SIGSEGV, current, 0);
931 retval = -EFAULT; /* Nobody gets to see this, but.. */
932 goto out_free_dentry;
933 }
934
935 if (elf_interpreter) {
936 if (interpreter_type == INTERPRETER_AOUT)
937 elf_entry = load_aout_interp(&loc->interp_ex,
938 interpreter);
939 else
940 elf_entry = load_elf_interp(&loc->interp_elf_ex,
941 interpreter,
942 &interp_load_addr);
943 if (BAD_ADDR(elf_entry)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944 force_sig(SIGSEGV, current);
Chuck Ebbertce510592006-07-03 00:24:14 -0700945 retval = IS_ERR((void *)elf_entry) ?
946 (int)elf_entry : -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947 goto out_free_dentry;
948 }
949 reloc_func_desc = interp_load_addr;
950
951 allow_write_access(interpreter);
952 fput(interpreter);
953 kfree(elf_interpreter);
954 } else {
955 elf_entry = loc->elf_ex.e_entry;
Suresh Siddha5342fba2006-02-26 04:18:28 +0100956 if (BAD_ADDR(elf_entry)) {
Chuck Ebbertce510592006-07-03 00:24:14 -0700957 force_sig(SIGSEGV, current);
958 retval = -EINVAL;
Suresh Siddha5342fba2006-02-26 04:18:28 +0100959 goto out_free_dentry;
960 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961 }
962
963 kfree(elf_phdata);
964
965 if (interpreter_type != INTERPRETER_AOUT)
966 sys_close(elf_exec_fileno);
967
968 set_binfmt(&elf_format);
969
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -0700970#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
971 retval = arch_setup_additional_pages(bprm, executable_stack);
972 if (retval < 0) {
973 send_sig(SIGKILL, current, 0);
Roland McGrath18c8baf2005-04-28 15:17:19 -0700974 goto out;
Benjamin Herrenschmidt547ee842005-04-16 15:24:35 -0700975 }
976#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
977
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978 compute_creds(bprm);
979 current->flags &= ~PF_FORKNOEXEC;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700980 create_elf_tables(bprm, &loc->elf_ex,
981 (interpreter_type == INTERPRETER_AOUT),
982 load_addr, interp_load_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983 /* N.B. passed_fileno might not be initialized? */
984 if (interpreter_type == INTERPRETER_AOUT)
985 current->mm->arg_start += strlen(passed_fileno) + 1;
986 current->mm->end_code = end_code;
987 current->mm->start_code = start_code;
988 current->mm->start_data = start_data;
989 current->mm->end_data = end_data;
990 current->mm->start_stack = bprm->p;
991
992 if (current->personality & MMAP_PAGE_ZERO) {
993 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
994 and some applications "depend" upon this behavior.
995 Since we do not have the power to recompile these, we
Jesper Juhlf4e5cc22006-06-23 02:05:35 -0700996 emulate the SVr4 behavior. Sigh. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700997 down_write(&current->mm->mmap_sem);
998 error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
999 MAP_FIXED | MAP_PRIVATE, 0);
1000 up_write(&current->mm->mmap_sem);
1001 }
1002
1003#ifdef ELF_PLAT_INIT
1004 /*
1005 * The ABI may specify that certain registers be set up in special
1006 * ways (on i386 %edx is the address of a DT_FINI function, for
1007 * example. In addition, it may also specify (eg, PowerPC64 ELF)
1008 * that the e_entry field is the address of the function descriptor
1009 * for the startup routine, rather than the address of the startup
1010 * routine itself. This macro performs whatever initialization to
1011 * the regs structure is required as well as any relocations to the
1012 * function descriptor entries when executing dynamically links apps.
1013 */
1014 ELF_PLAT_INIT(regs, reloc_func_desc);
1015#endif
1016
1017 start_thread(regs, elf_entry, bprm->p);
1018 if (unlikely(current->ptrace & PT_PTRACED)) {
1019 if (current->ptrace & PT_TRACE_EXEC)
1020 ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP);
1021 else
1022 send_sig(SIGTRAP, current, 0);
1023 }
1024 retval = 0;
1025out:
1026 kfree(loc);
1027out_ret:
1028 return retval;
1029
1030 /* error cleanup */
1031out_free_dentry:
1032 allow_write_access(interpreter);
1033 if (interpreter)
1034 fput(interpreter);
1035out_free_interp:
Jesper Juhlf99d49a2005-11-07 01:01:34 -08001036 kfree(elf_interpreter);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001037out_free_file:
1038 sys_close(elf_exec_fileno);
1039out_free_fh:
1040 if (files) {
1041 put_files_struct(current->files);
1042 current->files = files;
1043 }
1044out_free_ph:
1045 kfree(elf_phdata);
1046 goto out;
1047}
1048
1049/* This is really simpleminded and specialized - we are loading an
1050 a.out library that is given an ELF header. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051static int load_elf_library(struct file *file)
1052{
1053 struct elf_phdr *elf_phdata;
1054 struct elf_phdr *eppnt;
1055 unsigned long elf_bss, bss, len;
1056 int retval, error, i, j;
1057 struct elfhdr elf_ex;
1058
1059 error = -ENOEXEC;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001060 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001061 if (retval != sizeof(elf_ex))
1062 goto out;
1063
1064 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
1065 goto out;
1066
1067 /* First of all, some simple consistency checks */
1068 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001069 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001070 goto out;
1071
1072 /* Now read in all of the header information */
1073
1074 j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
1075 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1076
1077 error = -ENOMEM;
1078 elf_phdata = kmalloc(j, GFP_KERNEL);
1079 if (!elf_phdata)
1080 goto out;
1081
1082 eppnt = elf_phdata;
1083 error = -ENOEXEC;
1084 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
1085 if (retval != j)
1086 goto out_free_ph;
1087
1088 for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
1089 if ((eppnt + i)->p_type == PT_LOAD)
1090 j++;
1091 if (j != 1)
1092 goto out_free_ph;
1093
1094 while (eppnt->p_type != PT_LOAD)
1095 eppnt++;
1096
1097 /* Now use mmap to map the library into memory. */
1098 down_write(&current->mm->mmap_sem);
1099 error = do_mmap(file,
1100 ELF_PAGESTART(eppnt->p_vaddr),
1101 (eppnt->p_filesz +
1102 ELF_PAGEOFFSET(eppnt->p_vaddr)),
1103 PROT_READ | PROT_WRITE | PROT_EXEC,
1104 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
1105 (eppnt->p_offset -
1106 ELF_PAGEOFFSET(eppnt->p_vaddr)));
1107 up_write(&current->mm->mmap_sem);
1108 if (error != ELF_PAGESTART(eppnt->p_vaddr))
1109 goto out_free_ph;
1110
1111 elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
1112 if (padzero(elf_bss)) {
1113 error = -EFAULT;
1114 goto out_free_ph;
1115 }
1116
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001117 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
1118 ELF_MIN_ALIGN - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001119 bss = eppnt->p_memsz + eppnt->p_vaddr;
1120 if (bss > len) {
1121 down_write(&current->mm->mmap_sem);
1122 do_brk(len, bss - len);
1123 up_write(&current->mm->mmap_sem);
1124 }
1125 error = 0;
1126
1127out_free_ph:
1128 kfree(elf_phdata);
1129out:
1130 return error;
1131}
1132
1133/*
1134 * Note that some platforms still use traditional core dumps and not
1135 * the ELF core dump. Each platform can select it as appropriate.
1136 */
Matt Mackall708e9a72006-01-08 01:05:25 -08001137#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001138
1139/*
1140 * ELF core dumper
1141 *
1142 * Modelled on fs/exec.c:aout_core_dump()
1143 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1144 */
1145/*
1146 * These are the only things you should do on a core-file: use only these
1147 * functions to write out all the necessary info.
1148 */
1149static int dump_write(struct file *file, const void *addr, int nr)
1150{
1151 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
1152}
1153
Daniel Jacobowitz5db92852005-06-15 22:26:34 -07001154static int dump_seek(struct file *file, loff_t off)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155{
1156 if (file->f_op->llseek) {
1157 if (file->f_op->llseek(file, off, 0) != off)
1158 return 0;
1159 } else
1160 file->f_pos = off;
1161 return 1;
1162}
1163
1164/*
1165 * Decide whether a segment is worth dumping; default is yes to be
1166 * sure (missing info is worse than too much; etc).
1167 * Personally I'd include everything, and use the coredump limit...
1168 *
1169 * I think we should skip something. But I am not sure how. H.J.
1170 */
1171static int maydump(struct vm_area_struct *vma)
1172{
1173 /* Do not dump I/O mapped devices or special mappings */
1174 if (vma->vm_flags & (VM_IO | VM_RESERVED))
1175 return 0;
1176
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001177 /* Dump shared memory only if mapped from an anonymous file. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178 if (vma->vm_flags & VM_SHARED)
1179 return vma->vm_file->f_dentry->d_inode->i_nlink == 0;
1180
1181 /* If it hasn't been written to, don't write it out */
1182 if (!vma->anon_vma)
1183 return 0;
1184
1185 return 1;
1186}
1187
Linus Torvalds1da177e2005-04-16 15:20:36 -07001188/* An ELF note in memory */
1189struct memelfnote
1190{
1191 const char *name;
1192 int type;
1193 unsigned int datasz;
1194 void *data;
1195};
1196
1197static int notesize(struct memelfnote *en)
1198{
1199 int sz;
1200
1201 sz = sizeof(struct elf_note);
1202 sz += roundup(strlen(en->name) + 1, 4);
1203 sz += roundup(en->datasz, 4);
1204
1205 return sz;
1206}
1207
1208#define DUMP_WRITE(addr, nr) \
1209 do { if (!dump_write(file, (addr), (nr))) return 0; } while(0)
1210#define DUMP_SEEK(off) \
1211 do { if (!dump_seek(file, (off))) return 0; } while(0)
1212
1213static int writenote(struct memelfnote *men, struct file *file)
1214{
1215 struct elf_note en;
1216
1217 en.n_namesz = strlen(men->name) + 1;
1218 en.n_descsz = men->datasz;
1219 en.n_type = men->type;
1220
1221 DUMP_WRITE(&en, sizeof(en));
1222 DUMP_WRITE(men->name, en.n_namesz);
1223 /* XXX - cast from long long to long to avoid need for libgcc.a */
1224 DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
1225 DUMP_WRITE(men->data, men->datasz);
1226 DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
1227
1228 return 1;
1229}
1230#undef DUMP_WRITE
1231#undef DUMP_SEEK
1232
1233#define DUMP_WRITE(addr, nr) \
1234 if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
1235 goto end_coredump;
1236#define DUMP_SEEK(off) \
1237 if (!dump_seek(file, (off))) \
1238 goto end_coredump;
1239
Arjan van de Ven858119e2006-01-14 13:20:43 -08001240static void fill_elf_header(struct elfhdr *elf, int segs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241{
1242 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1243 elf->e_ident[EI_CLASS] = ELF_CLASS;
1244 elf->e_ident[EI_DATA] = ELF_DATA;
1245 elf->e_ident[EI_VERSION] = EV_CURRENT;
1246 elf->e_ident[EI_OSABI] = ELF_OSABI;
1247 memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
1248
1249 elf->e_type = ET_CORE;
1250 elf->e_machine = ELF_ARCH;
1251 elf->e_version = EV_CURRENT;
1252 elf->e_entry = 0;
1253 elf->e_phoff = sizeof(struct elfhdr);
1254 elf->e_shoff = 0;
1255 elf->e_flags = ELF_CORE_EFLAGS;
1256 elf->e_ehsize = sizeof(struct elfhdr);
1257 elf->e_phentsize = sizeof(struct elf_phdr);
1258 elf->e_phnum = segs;
1259 elf->e_shentsize = 0;
1260 elf->e_shnum = 0;
1261 elf->e_shstrndx = 0;
1262 return;
1263}
1264
Arjan van de Ven858119e2006-01-14 13:20:43 -08001265static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, off_t offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001266{
1267 phdr->p_type = PT_NOTE;
1268 phdr->p_offset = offset;
1269 phdr->p_vaddr = 0;
1270 phdr->p_paddr = 0;
1271 phdr->p_filesz = sz;
1272 phdr->p_memsz = 0;
1273 phdr->p_flags = 0;
1274 phdr->p_align = 0;
1275 return;
1276}
1277
1278static void fill_note(struct memelfnote *note, const char *name, int type,
1279 unsigned int sz, void *data)
1280{
1281 note->name = name;
1282 note->type = type;
1283 note->datasz = sz;
1284 note->data = data;
1285 return;
1286}
1287
1288/*
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001289 * fill up all the fields in prstatus from the given task struct, except
1290 * registers which need to be filled up separately.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001291 */
1292static void fill_prstatus(struct elf_prstatus *prstatus,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001293 struct task_struct *p, long signr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001294{
1295 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1296 prstatus->pr_sigpend = p->pending.signal.sig[0];
1297 prstatus->pr_sighold = p->blocked.sig[0];
1298 prstatus->pr_pid = p->pid;
1299 prstatus->pr_ppid = p->parent->pid;
1300 prstatus->pr_pgrp = process_group(p);
1301 prstatus->pr_sid = p->signal->session;
1302 if (thread_group_leader(p)) {
1303 /*
1304 * This is the record for the group leader. Add in the
1305 * cumulative times of previous dead threads. This total
1306 * won't include the time of each live thread whose state
1307 * is included in the core dump. The final total reported
1308 * to our parent process when it calls wait4 will include
1309 * those sums as well as the little bit more time it takes
1310 * this and each other thread to finish dying after the
1311 * core dump synchronization phase.
1312 */
1313 cputime_to_timeval(cputime_add(p->utime, p->signal->utime),
1314 &prstatus->pr_utime);
1315 cputime_to_timeval(cputime_add(p->stime, p->signal->stime),
1316 &prstatus->pr_stime);
1317 } else {
1318 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1319 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1320 }
1321 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1322 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1323}
1324
1325static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1326 struct mm_struct *mm)
1327{
Greg Kroah-Hartmana84a5052005-05-11 00:10:44 -07001328 unsigned int i, len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001329
1330 /* first copy the parameters from user space */
1331 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1332
1333 len = mm->arg_end - mm->arg_start;
1334 if (len >= ELF_PRARGSZ)
1335 len = ELF_PRARGSZ-1;
1336 if (copy_from_user(&psinfo->pr_psargs,
1337 (const char __user *)mm->arg_start, len))
1338 return -EFAULT;
1339 for(i = 0; i < len; i++)
1340 if (psinfo->pr_psargs[i] == 0)
1341 psinfo->pr_psargs[i] = ' ';
1342 psinfo->pr_psargs[len] = 0;
1343
1344 psinfo->pr_pid = p->pid;
1345 psinfo->pr_ppid = p->parent->pid;
1346 psinfo->pr_pgrp = process_group(p);
1347 psinfo->pr_sid = p->signal->session;
1348
1349 i = p->state ? ffz(~p->state) + 1 : 0;
1350 psinfo->pr_state = i;
Carsten Otte55148542006-03-25 03:08:22 -08001351 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001352 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1353 psinfo->pr_nice = task_nice(p);
1354 psinfo->pr_flag = p->flags;
1355 SET_UID(psinfo->pr_uid, p->uid);
1356 SET_GID(psinfo->pr_gid, p->gid);
1357 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1358
1359 return 0;
1360}
1361
1362/* Here is the structure in which status of each thread is captured. */
1363struct elf_thread_status
1364{
1365 struct list_head list;
1366 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1367 elf_fpregset_t fpu; /* NT_PRFPREG */
1368 struct task_struct *thread;
1369#ifdef ELF_CORE_COPY_XFPREGS
1370 elf_fpxregset_t xfpu; /* NT_PRXFPREG */
1371#endif
1372 struct memelfnote notes[3];
1373 int num_notes;
1374};
1375
1376/*
1377 * In order to add the specific thread information for the elf file format,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001378 * we need to keep a linked list of every threads pr_status and then create
1379 * a single section for them in the final core file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001380 */
1381static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1382{
1383 int sz = 0;
1384 struct task_struct *p = t->thread;
1385 t->num_notes = 0;
1386
1387 fill_prstatus(&t->prstatus, p, signr);
1388 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1389
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001390 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1391 &(t->prstatus));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001392 t->num_notes++;
1393 sz += notesize(&t->notes[0]);
1394
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001395 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1396 &t->fpu))) {
1397 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1398 &(t->fpu));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001399 t->num_notes++;
1400 sz += notesize(&t->notes[1]);
1401 }
1402
1403#ifdef ELF_CORE_COPY_XFPREGS
1404 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001405 fill_note(&t->notes[2], "LINUX", NT_PRXFPREG, sizeof(t->xfpu),
1406 &t->xfpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001407 t->num_notes++;
1408 sz += notesize(&t->notes[2]);
1409 }
1410#endif
1411 return sz;
1412}
1413
1414/*
1415 * Actual dumper
1416 *
1417 * This is a two-pass process; first we find the offsets of the bits,
1418 * and then they are actually written out. If we run out of core limit
1419 * we just truncate.
1420 */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001421static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001422{
1423#define NUM_NOTES 6
1424 int has_dumped = 0;
1425 mm_segment_t fs;
1426 int segs;
1427 size_t size = 0;
1428 int i;
1429 struct vm_area_struct *vma;
1430 struct elfhdr *elf = NULL;
1431 off_t offset = 0, dataoff;
1432 unsigned long limit = current->signal->rlim[RLIMIT_CORE].rlim_cur;
1433 int numnote;
1434 struct memelfnote *notes = NULL;
1435 struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */
1436 struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */
1437 struct task_struct *g, *p;
1438 LIST_HEAD(thread_list);
1439 struct list_head *t;
1440 elf_fpregset_t *fpu = NULL;
1441#ifdef ELF_CORE_COPY_XFPREGS
1442 elf_fpxregset_t *xfpu = NULL;
1443#endif
1444 int thread_status_size = 0;
1445 elf_addr_t *auxv;
1446
1447 /*
1448 * We no longer stop all VM operations.
1449 *
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001450 * This is because those proceses that could possibly change map_count
1451 * or the mmap / vma pages are now blocked in do_exit on current
1452 * finishing this core dump.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001453 *
1454 * Only ptrace can touch these memory addresses, but it doesn't change
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001455 * the map_count or the pages allocated. So no possibility of crashing
Linus Torvalds1da177e2005-04-16 15:20:36 -07001456 * exists while dumping the mm->vm_next areas to the core file.
1457 */
1458
1459 /* alloc memory for large data structures: too large to be on stack */
1460 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1461 if (!elf)
1462 goto cleanup;
1463 prstatus = kmalloc(sizeof(*prstatus), GFP_KERNEL);
1464 if (!prstatus)
1465 goto cleanup;
1466 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1467 if (!psinfo)
1468 goto cleanup;
1469 notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote), GFP_KERNEL);
1470 if (!notes)
1471 goto cleanup;
1472 fpu = kmalloc(sizeof(*fpu), GFP_KERNEL);
1473 if (!fpu)
1474 goto cleanup;
1475#ifdef ELF_CORE_COPY_XFPREGS
1476 xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL);
1477 if (!xfpu)
1478 goto cleanup;
1479#endif
1480
1481 if (signr) {
1482 struct elf_thread_status *tmp;
1483 read_lock(&tasklist_lock);
1484 do_each_thread(g,p)
1485 if (current->mm == p->mm && current != p) {
Oliver Neukum11b0b5a2006-03-25 03:08:13 -08001486 tmp = kzalloc(sizeof(*tmp), GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487 if (!tmp) {
1488 read_unlock(&tasklist_lock);
1489 goto cleanup;
1490 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001491 INIT_LIST_HEAD(&tmp->list);
1492 tmp->thread = p;
1493 list_add(&tmp->list, &thread_list);
1494 }
1495 while_each_thread(g,p);
1496 read_unlock(&tasklist_lock);
1497 list_for_each(t, &thread_list) {
1498 struct elf_thread_status *tmp;
1499 int sz;
1500
1501 tmp = list_entry(t, struct elf_thread_status, list);
1502 sz = elf_dump_thread_status(signr, tmp);
1503 thread_status_size += sz;
1504 }
1505 }
1506 /* now collect the dump for the current */
1507 memset(prstatus, 0, sizeof(*prstatus));
1508 fill_prstatus(prstatus, current, signr);
1509 elf_core_copy_regs(&prstatus->pr_reg, regs);
1510
1511 segs = current->mm->map_count;
1512#ifdef ELF_CORE_EXTRA_PHDRS
1513 segs += ELF_CORE_EXTRA_PHDRS;
1514#endif
1515
1516 /* Set up header */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001517 fill_elf_header(elf, segs + 1); /* including notes section */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001518
1519 has_dumped = 1;
1520 current->flags |= PF_DUMPCORE;
1521
1522 /*
1523 * Set up the notes in similar form to SVR4 core dumps made
1524 * with info from their /proc.
1525 */
1526
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001527 fill_note(notes + 0, "CORE", NT_PRSTATUS, sizeof(*prstatus), prstatus);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001528 fill_psinfo(psinfo, current->group_leader, current->mm);
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001529 fill_note(notes + 1, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530
Eric W. Biedermana9289722005-10-30 15:02:08 -08001531 numnote = 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001532
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001533 auxv = (elf_addr_t *)current->mm->saved_auxv;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001534
1535 i = 0;
1536 do
1537 i += 2;
1538 while (auxv[i - 2] != AT_NULL);
1539 fill_note(&notes[numnote++], "CORE", NT_AUXV,
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001540 i * sizeof(elf_addr_t), auxv);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001541
1542 /* Try to dump the FPU. */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001543 if ((prstatus->pr_fpvalid =
1544 elf_core_copy_task_fpregs(current, regs, fpu)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001545 fill_note(notes + numnote++,
1546 "CORE", NT_PRFPREG, sizeof(*fpu), fpu);
1547#ifdef ELF_CORE_COPY_XFPREGS
1548 if (elf_core_copy_task_xfpregs(current, xfpu))
1549 fill_note(notes + numnote++,
1550 "LINUX", NT_PRXFPREG, sizeof(*xfpu), xfpu);
1551#endif
1552
1553 fs = get_fs();
1554 set_fs(KERNEL_DS);
1555
1556 DUMP_WRITE(elf, sizeof(*elf));
1557 offset += sizeof(*elf); /* Elf header */
1558 offset += (segs+1) * sizeof(struct elf_phdr); /* Program headers */
1559
1560 /* Write notes phdr entry */
1561 {
1562 struct elf_phdr phdr;
1563 int sz = 0;
1564
1565 for (i = 0; i < numnote; i++)
1566 sz += notesize(notes + i);
1567
1568 sz += thread_status_size;
1569
1570 fill_elf_note_phdr(&phdr, sz, offset);
1571 offset += sz;
1572 DUMP_WRITE(&phdr, sizeof(phdr));
1573 }
1574
1575 /* Page-align dumped data */
1576 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1577
1578 /* Write program headers for segments dump */
1579 for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
1580 struct elf_phdr phdr;
1581 size_t sz;
1582
1583 sz = vma->vm_end - vma->vm_start;
1584
1585 phdr.p_type = PT_LOAD;
1586 phdr.p_offset = offset;
1587 phdr.p_vaddr = vma->vm_start;
1588 phdr.p_paddr = 0;
1589 phdr.p_filesz = maydump(vma) ? sz : 0;
1590 phdr.p_memsz = sz;
1591 offset += phdr.p_filesz;
1592 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001593 if (vma->vm_flags & VM_WRITE)
1594 phdr.p_flags |= PF_W;
1595 if (vma->vm_flags & VM_EXEC)
1596 phdr.p_flags |= PF_X;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001597 phdr.p_align = ELF_EXEC_PAGESIZE;
1598
1599 DUMP_WRITE(&phdr, sizeof(phdr));
1600 }
1601
1602#ifdef ELF_CORE_WRITE_EXTRA_PHDRS
1603 ELF_CORE_WRITE_EXTRA_PHDRS;
1604#endif
1605
1606 /* write out the notes section */
1607 for (i = 0; i < numnote; i++)
1608 if (!writenote(notes + i, file))
1609 goto end_coredump;
1610
1611 /* write out the thread status notes section */
1612 list_for_each(t, &thread_list) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001613 struct elf_thread_status *tmp =
1614 list_entry(t, struct elf_thread_status, list);
1615
Linus Torvalds1da177e2005-04-16 15:20:36 -07001616 for (i = 0; i < tmp->num_notes; i++)
1617 if (!writenote(&tmp->notes[i], file))
1618 goto end_coredump;
1619 }
1620
1621 DUMP_SEEK(dataoff);
1622
1623 for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
1624 unsigned long addr;
1625
1626 if (!maydump(vma))
1627 continue;
1628
1629 for (addr = vma->vm_start;
1630 addr < vma->vm_end;
1631 addr += PAGE_SIZE) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001632 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001633 struct vm_area_struct *vma;
1634
1635 if (get_user_pages(current, current->mm, addr, 1, 0, 1,
1636 &page, &vma) <= 0) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001637 DUMP_SEEK(file->f_pos + PAGE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001638 } else {
1639 if (page == ZERO_PAGE(addr)) {
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001640 DUMP_SEEK(file->f_pos + PAGE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001641 } else {
1642 void *kaddr;
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001643 flush_cache_page(vma, addr,
1644 page_to_pfn(page));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001645 kaddr = kmap(page);
1646 if ((size += PAGE_SIZE) > limit ||
1647 !dump_write(file, kaddr,
1648 PAGE_SIZE)) {
1649 kunmap(page);
1650 page_cache_release(page);
1651 goto end_coredump;
1652 }
1653 kunmap(page);
1654 }
1655 page_cache_release(page);
1656 }
1657 }
1658 }
1659
1660#ifdef ELF_CORE_WRITE_EXTRA_DATA
1661 ELF_CORE_WRITE_EXTRA_DATA;
1662#endif
1663
Jesper Juhl74da6cd2006-01-11 01:51:26 +01001664 if ((off_t)file->f_pos != offset) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001665 /* Sanity check */
Jesper Juhlf4e5cc22006-06-23 02:05:35 -07001666 printk(KERN_WARNING
1667 "elf_core_dump: file->f_pos (%ld) != offset (%ld)\n",
Jesper Juhl74da6cd2006-01-11 01:51:26 +01001668 (off_t)file->f_pos, offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669 }
1670
1671end_coredump:
1672 set_fs(fs);
1673
1674cleanup:
Jesper Juhl74da6cd2006-01-11 01:51:26 +01001675 while (!list_empty(&thread_list)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001676 struct list_head *tmp = thread_list.next;
1677 list_del(tmp);
1678 kfree(list_entry(tmp, struct elf_thread_status, list));
1679 }
1680
1681 kfree(elf);
1682 kfree(prstatus);
1683 kfree(psinfo);
1684 kfree(notes);
1685 kfree(fpu);
1686#ifdef ELF_CORE_COPY_XFPREGS
1687 kfree(xfpu);
1688#endif
1689 return has_dumped;
1690#undef NUM_NOTES
1691}
1692
1693#endif /* USE_ELF_CORE_DUMP */
1694
1695static int __init init_elf_binfmt(void)
1696{
1697 return register_binfmt(&elf_format);
1698}
1699
1700static void __exit exit_elf_binfmt(void)
1701{
1702 /* Remove the COFF and ELF loaders. */
1703 unregister_binfmt(&elf_format);
1704}
1705
1706core_initcall(init_elf_binfmt);
1707module_exit(exit_elf_binfmt);
1708MODULE_LICENSE("GPL");