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ixgbe: Cleanup incorrect header comments
[linux-2.6/libata-dev.git] / fs / binfmt_elf.c
blobedd90c49003cff3b2fdf62ecb0e406007369eedb
1 /*
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/mm.h>
16 #include <linux/mman.h>
17 #include <linux/errno.h>
18 #include <linux/signal.h>
19 #include <linux/binfmts.h>
20 #include <linux/string.h>
21 #include <linux/file.h>
22 #include <linux/slab.h>
23 #include <linux/personality.h>
24 #include <linux/elfcore.h>
25 #include <linux/init.h>
26 #include <linux/highuid.h>
27 #include <linux/compiler.h>
28 #include <linux/highmem.h>
29 #include <linux/pagemap.h>
30 #include <linux/security.h>
31 #include <linux/random.h>
32 #include <linux/elf.h>
33 #include <linux/utsname.h>
34 #include <asm/uaccess.h>
35 #include <asm/param.h>
36 #include <asm/page.h>
37
38 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs);
39 static int load_elf_library(struct file *);
40 static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *,
41 int, int, unsigned long);
42
43 /*
44 * If we don't support core dumping, then supply a NULL so we
45 * don't even try.
46 */
47 #ifdef CONFIG_ELF_CORE
48 static int elf_core_dump(struct coredump_params *cprm);
49 #else
50 #define elf_core_dump NULL
51 #endif
52
53 #if ELF_EXEC_PAGESIZE > PAGE_SIZE
54 #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
55 #else
56 #define ELF_MIN_ALIGN PAGE_SIZE
57 #endif
58
59 #ifndef ELF_CORE_EFLAGS
60 #define ELF_CORE_EFLAGS 0
61 #endif
62
63 #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
64 #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
65 #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
66
67 static struct linux_binfmt elf_format = {
68 .module = THIS_MODULE,
69 .load_binary = load_elf_binary,
70 .load_shlib = load_elf_library,
71 .core_dump = elf_core_dump,
72 .min_coredump = ELF_EXEC_PAGESIZE,
73 .hasvdso = 1
74 };
75
76 #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
77
78 static int set_brk(unsigned long start, unsigned long end)
79 {
80 start = ELF_PAGEALIGN(start);
81 end = ELF_PAGEALIGN(end);
82 if (end > start) {
83 unsigned long addr;
84 down_write(&current->mm->mmap_sem);
85 addr = do_brk(start, end - start);
86 up_write(&current->mm->mmap_sem);
87 if (BAD_ADDR(addr))
88 return addr;
89 }
90 current->mm->start_brk = current->mm->brk = end;
91 return 0;
92 }
93
94 /* We need to explicitly zero any fractional pages
95 after the data section (i.e. bss). This would
96 contain the junk from the file that should not
97 be in memory
98 */
99 static int padzero(unsigned long elf_bss)
100 {
101 unsigned long nbyte;
102
103 nbyte = ELF_PAGEOFFSET(elf_bss);
104 if (nbyte) {
105 nbyte = ELF_MIN_ALIGN - nbyte;
106 if (clear_user((void __user *) elf_bss, nbyte))
107 return -EFAULT;
108 }
109 return 0;
110 }
111
112 /* Let's use some macros to make this stack manipulation a little clearer */
113 #ifdef CONFIG_STACK_GROWSUP
114 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
115 #define STACK_ROUND(sp, items) \
116 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
117 #define STACK_ALLOC(sp, len) ({ \
118 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
119 old_sp; })
120 #else
121 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
122 #define STACK_ROUND(sp, items) \
123 (((unsigned long) (sp - items)) &~ 15UL)
124 #define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
125 #endif
126
127 #ifndef ELF_BASE_PLATFORM
128 /*
129 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
130 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
131 * will be copied to the user stack in the same manner as AT_PLATFORM.
132 */
133 #define ELF_BASE_PLATFORM NULL
134 #endif
135
136 static int
137 create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
138 unsigned long load_addr, unsigned long interp_load_addr)
139 {
140 unsigned long p = bprm->p;
141 int argc = bprm->argc;
142 int envc = bprm->envc;
143 elf_addr_t __user *argv;
144 elf_addr_t __user *envp;
145 elf_addr_t __user *sp;
146 elf_addr_t __user *u_platform;
147 elf_addr_t __user *u_base_platform;
148 elf_addr_t __user *u_rand_bytes;
149 const char *k_platform = ELF_PLATFORM;
150 const char *k_base_platform = ELF_BASE_PLATFORM;
151 unsigned char k_rand_bytes[16];
152 int items;
153 elf_addr_t *elf_info;
154 int ei_index = 0;
155 const struct cred *cred = current_cred();
156 struct vm_area_struct *vma;
157
158 /*
159 * In some cases (e.g. Hyper-Threading), we want to avoid L1
160 * evictions by the processes running on the same package. One
161 * thing we can do is to shuffle the initial stack for them.
162 */
163
164 p = arch_align_stack(p);
165
166 /*
167 * If this architecture has a platform capability string, copy it
168 * to userspace. In some cases (Sparc), this info is impossible
169 * for userspace to get any other way, in others (i386) it is
170 * merely difficult.
171 */
172 u_platform = NULL;
173 if (k_platform) {
174 size_t len = strlen(k_platform) + 1;
175
176 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
177 if (__copy_to_user(u_platform, k_platform, len))
178 return -EFAULT;
179 }
180
181 /*
182 * If this architecture has a "base" platform capability
183 * string, copy it to userspace.
184 */
185 u_base_platform = NULL;
186 if (k_base_platform) {
187 size_t len = strlen(k_base_platform) + 1;
188
189 u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
190 if (__copy_to_user(u_base_platform, k_base_platform, len))
191 return -EFAULT;
192 }
193
194 /*
195 * Generate 16 random bytes for userspace PRNG seeding.
196 */
197 get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
198 u_rand_bytes = (elf_addr_t __user *)
199 STACK_ALLOC(p, sizeof(k_rand_bytes));
200 if (__copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes)))
201 return -EFAULT;
202
203 /* Create the ELF interpreter info */
204 elf_info = (elf_addr_t *)current->mm->saved_auxv;
205 /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
206 #define NEW_AUX_ENT(id, val) \
207 do { \
208 elf_info[ei_index++] = id; \
209 elf_info[ei_index++] = val; \
210 } while (0)
211
212 #ifdef ARCH_DLINFO
213 /*
214 * ARCH_DLINFO must come first so PPC can do its special alignment of
215 * AUXV.
216 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
217 * ARCH_DLINFO changes
218 */
219 ARCH_DLINFO;
220 #endif
221 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
222 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
223 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
224 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
225 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
226 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
227 NEW_AUX_ENT(AT_BASE, interp_load_addr);
228 NEW_AUX_ENT(AT_FLAGS, 0);
229 NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
230 NEW_AUX_ENT(AT_UID, cred->uid);
231 NEW_AUX_ENT(AT_EUID, cred->euid);
232 NEW_AUX_ENT(AT_GID, cred->gid);
233 NEW_AUX_ENT(AT_EGID, cred->egid);
234 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
235 NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
236 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
237 if (k_platform) {
238 NEW_AUX_ENT(AT_PLATFORM,
239 (elf_addr_t)(unsigned long)u_platform);
240 }
241 if (k_base_platform) {
242 NEW_AUX_ENT(AT_BASE_PLATFORM,
243 (elf_addr_t)(unsigned long)u_base_platform);
244 }
245 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
246 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
247 }
248 #undef NEW_AUX_ENT
249 /* AT_NULL is zero; clear the rest too */
250 memset(&elf_info[ei_index], 0,
251 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
252
253 /* And advance past the AT_NULL entry. */
254 ei_index += 2;
255
256 sp = STACK_ADD(p, ei_index);
257
258 items = (argc + 1) + (envc + 1) + 1;
259 bprm->p = STACK_ROUND(sp, items);
260
261 /* Point sp at the lowest address on the stack */
262 #ifdef CONFIG_STACK_GROWSUP
263 sp = (elf_addr_t __user *)bprm->p - items - ei_index;
264 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
265 #else
266 sp = (elf_addr_t __user *)bprm->p;
267 #endif
268
269
270 /*
271 * Grow the stack manually; some architectures have a limit on how
272 * far ahead a user-space access may be in order to grow the stack.
273 */
274 vma = find_extend_vma(current->mm, bprm->p);
275 if (!vma)
276 return -EFAULT;
277
278 /* Now, let's put argc (and argv, envp if appropriate) on the stack */
279 if (__put_user(argc, sp++))
280 return -EFAULT;
281 argv = sp;
282 envp = argv + argc + 1;
283
284 /* Populate argv and envp */
285 p = current->mm->arg_end = current->mm->arg_start;
286 while (argc-- > 0) {
287 size_t len;
288 if (__put_user((elf_addr_t)p, argv++))
289 return -EFAULT;
290 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
291 if (!len || len > MAX_ARG_STRLEN)
292 return -EINVAL;
293 p += len;
294 }
295 if (__put_user(0, argv))
296 return -EFAULT;
297 current->mm->arg_end = current->mm->env_start = p;
298 while (envc-- > 0) {
299 size_t len;
300 if (__put_user((elf_addr_t)p, envp++))
301 return -EFAULT;
302 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
303 if (!len || len > MAX_ARG_STRLEN)
304 return -EINVAL;
305 p += len;
306 }
307 if (__put_user(0, envp))
308 return -EFAULT;
309 current->mm->env_end = p;
310
311 /* Put the elf_info on the stack in the right place. */
312 sp = (elf_addr_t __user *)envp + 1;
313 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
314 return -EFAULT;
315 return 0;
316 }
317
318 #ifndef elf_map
319
320 static unsigned long elf_map(struct file *filep, unsigned long addr,
321 struct elf_phdr *eppnt, int prot, int type,
322 unsigned long total_size)
323 {
324 unsigned long map_addr;
325 unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
326 unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
327 addr = ELF_PAGESTART(addr);
328 size = ELF_PAGEALIGN(size);
329
330 /* mmap() will return -EINVAL if given a zero size, but a
331 * segment with zero filesize is perfectly valid */
332 if (!size)
333 return addr;
334
335 down_write(&current->mm->mmap_sem);
336 /*
337 * total_size is the size of the ELF (interpreter) image.
338 * The _first_ mmap needs to know the full size, otherwise
339 * randomization might put this image into an overlapping
340 * position with the ELF binary image. (since size < total_size)
341 * So we first map the 'big' image - and unmap the remainder at
342 * the end. (which unmap is needed for ELF images with holes.)
343 */
344 if (total_size) {
345 total_size = ELF_PAGEALIGN(total_size);
346 map_addr = do_mmap(filep, addr, total_size, prot, type, off);
347 if (!BAD_ADDR(map_addr))
348 do_munmap(current->mm, map_addr+size, total_size-size);
349 } else
350 map_addr = do_mmap(filep, addr, size, prot, type, off);
351
352 up_write(&current->mm->mmap_sem);
353 return(map_addr);
354 }
355
356 #endif /* !elf_map */
357
358 static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr)
359 {
360 int i, first_idx = -1, last_idx = -1;
361
362 for (i = 0; i < nr; i++) {
363 if (cmds[i].p_type == PT_LOAD) {
364 last_idx = i;
365 if (first_idx == -1)
366 first_idx = i;
367 }
368 }
369 if (first_idx == -1)
370 return 0;
371
372 return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz -
373 ELF_PAGESTART(cmds[first_idx].p_vaddr);
374 }
375
376
377 /* This is much more generalized than the library routine read function,
378 so we keep this separate. Technically the library read function
379 is only provided so that we can read a.out libraries that have
380 an ELF header */
381
382 static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
383 struct file *interpreter, unsigned long *interp_map_addr,
384 unsigned long no_base)
385 {
386 struct elf_phdr *elf_phdata;
387 struct elf_phdr *eppnt;
388 unsigned long load_addr = 0;
389 int load_addr_set = 0;
390 unsigned long last_bss = 0, elf_bss = 0;
391 unsigned long error = ~0UL;
392 unsigned long total_size;
393 int retval, i, size;
394
395 /* First of all, some simple consistency checks */
396 if (interp_elf_ex->e_type != ET_EXEC &&
397 interp_elf_ex->e_type != ET_DYN)
398 goto out;
399 if (!elf_check_arch(interp_elf_ex))
400 goto out;
401 if (!interpreter->f_op || !interpreter->f_op->mmap)
402 goto out;
403
404 /*
405 * If the size of this structure has changed, then punt, since
406 * we will be doing the wrong thing.
407 */
408 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
409 goto out;
410 if (interp_elf_ex->e_phnum < 1 ||
411 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
412 goto out;
413
414 /* Now read in all of the header information */
415 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
416 if (size > ELF_MIN_ALIGN)
417 goto out;
418 elf_phdata = kmalloc(size, GFP_KERNEL);
419 if (!elf_phdata)
420 goto out;
421
422 retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
423 (char *)elf_phdata,size);
424 error = -EIO;
425 if (retval != size) {
426 if (retval < 0)
427 error = retval;
428 goto out_close;
429 }
430
431 total_size = total_mapping_size(elf_phdata, interp_elf_ex->e_phnum);
432 if (!total_size) {
433 error = -EINVAL;
434 goto out_close;
435 }
436
437 eppnt = elf_phdata;
438 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
439 if (eppnt->p_type == PT_LOAD) {
440 int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
441 int elf_prot = 0;
442 unsigned long vaddr = 0;
443 unsigned long k, map_addr;
444
445 if (eppnt->p_flags & PF_R)
446 elf_prot = PROT_READ;
447 if (eppnt->p_flags & PF_W)
448 elf_prot |= PROT_WRITE;
449 if (eppnt->p_flags & PF_X)
450 elf_prot |= PROT_EXEC;
451 vaddr = eppnt->p_vaddr;
452 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
453 elf_type |= MAP_FIXED;
454 else if (no_base && interp_elf_ex->e_type == ET_DYN)
455 load_addr = -vaddr;
456
457 map_addr = elf_map(interpreter, load_addr + vaddr,
458 eppnt, elf_prot, elf_type, total_size);
459 total_size = 0;
460 if (!*interp_map_addr)
461 *interp_map_addr = map_addr;
462 error = map_addr;
463 if (BAD_ADDR(map_addr))
464 goto out_close;
465
466 if (!load_addr_set &&
467 interp_elf_ex->e_type == ET_DYN) {
468 load_addr = map_addr - ELF_PAGESTART(vaddr);
469 load_addr_set = 1;
470 }
471
472 /*
473 * Check to see if the section's size will overflow the
474 * allowed task size. Note that p_filesz must always be
475 * <= p_memsize so it's only necessary to check p_memsz.
476 */
477 k = load_addr + eppnt->p_vaddr;
478 if (BAD_ADDR(k) ||
479 eppnt->p_filesz > eppnt->p_memsz ||
480 eppnt->p_memsz > TASK_SIZE ||
481 TASK_SIZE - eppnt->p_memsz < k) {
482 error = -ENOMEM;
483 goto out_close;
484 }
485
486 /*
487 * Find the end of the file mapping for this phdr, and
488 * keep track of the largest address we see for this.
489 */
490 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
491 if (k > elf_bss)
492 elf_bss = k;
493
494 /*
495 * Do the same thing for the memory mapping - between
496 * elf_bss and last_bss is the bss section.
497 */
498 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
499 if (k > last_bss)
500 last_bss = k;
501 }
502 }
503
504 if (last_bss > elf_bss) {
505 /*
506 * Now fill out the bss section. First pad the last page up
507 * to the page boundary, and then perform a mmap to make sure
508 * that there are zero-mapped pages up to and including the
509 * last bss page.
510 */
511 if (padzero(elf_bss)) {
512 error = -EFAULT;
513 goto out_close;
514 }
515
516 /* What we have mapped so far */
517 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
518
519 /* Map the last of the bss segment */
520 down_write(&current->mm->mmap_sem);
521 error = do_brk(elf_bss, last_bss - elf_bss);
522 up_write(&current->mm->mmap_sem);
523 if (BAD_ADDR(error))
524 goto out_close;
525 }
526
527 error = load_addr;
528
529 out_close:
530 kfree(elf_phdata);
531 out:
532 return error;
533 }
534
535 /*
536 * These are the functions used to load ELF style executables and shared
537 * libraries. There is no binary dependent code anywhere else.
538 */
539
540 #define INTERPRETER_NONE 0
541 #define INTERPRETER_ELF 2
542
543 #ifndef STACK_RND_MASK
544 #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
545 #endif
546
547 static unsigned long randomize_stack_top(unsigned long stack_top)
548 {
549 unsigned int random_variable = 0;
550
551 if ((current->flags & PF_RANDOMIZE) &&
552 !(current->personality & ADDR_NO_RANDOMIZE)) {
553 random_variable = get_random_int() & STACK_RND_MASK;
554 random_variable <<= PAGE_SHIFT;
555 }
556 #ifdef CONFIG_STACK_GROWSUP
557 return PAGE_ALIGN(stack_top) + random_variable;
558 #else
559 return PAGE_ALIGN(stack_top) - random_variable;
560 #endif
561 }
562
563 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
564 {
565 struct file *interpreter = NULL; /* to shut gcc up */
566 unsigned long load_addr = 0, load_bias = 0;
567 int load_addr_set = 0;
568 char * elf_interpreter = NULL;
569 unsigned long error;
570 struct elf_phdr *elf_ppnt, *elf_phdata;
571 unsigned long elf_bss, elf_brk;
572 int retval, i;
573 unsigned int size;
574 unsigned long elf_entry;
575 unsigned long interp_load_addr = 0;
576 unsigned long start_code, end_code, start_data, end_data;
577 unsigned long reloc_func_desc = 0;
578 int executable_stack = EXSTACK_DEFAULT;
579 unsigned long def_flags = 0;
580 struct {
581 struct elfhdr elf_ex;
582 struct elfhdr interp_elf_ex;
583 } *loc;
584
585 loc = kmalloc(sizeof(*loc), GFP_KERNEL);
586 if (!loc) {
587 retval = -ENOMEM;
588 goto out_ret;
589 }
590
591 /* Get the exec-header */
592 loc->elf_ex = *((struct elfhdr *)bprm->buf);
593
594 retval = -ENOEXEC;
595 /* First of all, some simple consistency checks */
596 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
597 goto out;
598
599 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
600 goto out;
601 if (!elf_check_arch(&loc->elf_ex))
602 goto out;
603 if (!bprm->file->f_op||!bprm->file->f_op->mmap)
604 goto out;
605
606 /* Now read in all of the header information */
607 if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr))
608 goto out;
609 if (loc->elf_ex.e_phnum < 1 ||
610 loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr))
611 goto out;
612 size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr);
613 retval = -ENOMEM;
614 elf_phdata = kmalloc(size, GFP_KERNEL);
615 if (!elf_phdata)
616 goto out;
617
618 retval = kernel_read(bprm->file, loc->elf_ex.e_phoff,
619 (char *)elf_phdata, size);
620 if (retval != size) {
621 if (retval >= 0)
622 retval = -EIO;
623 goto out_free_ph;
624 }
625
626 elf_ppnt = elf_phdata;
627 elf_bss = 0;
628 elf_brk = 0;
629
630 start_code = ~0UL;
631 end_code = 0;
632 start_data = 0;
633 end_data = 0;
634
635 for (i = 0; i < loc->elf_ex.e_phnum; i++) {
636 if (elf_ppnt->p_type == PT_INTERP) {
637 /* This is the program interpreter used for
638 * shared libraries - for now assume that this
639 * is an a.out format binary
640 */
641 retval = -ENOEXEC;
642 if (elf_ppnt->p_filesz > PATH_MAX ||
643 elf_ppnt->p_filesz < 2)
644 goto out_free_ph;
645
646 retval = -ENOMEM;
647 elf_interpreter = kmalloc(elf_ppnt->p_filesz,
648 GFP_KERNEL);
649 if (!elf_interpreter)
650 goto out_free_ph;
651
652 retval = kernel_read(bprm->file, elf_ppnt->p_offset,
653 elf_interpreter,
654 elf_ppnt->p_filesz);
655 if (retval != elf_ppnt->p_filesz) {
656 if (retval >= 0)
657 retval = -EIO;
658 goto out_free_interp;
659 }
660 /* make sure path is NULL terminated */
661 retval = -ENOEXEC;
662 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
663 goto out_free_interp;
664
665 /*
666 * The early SET_PERSONALITY here is so that the lookup
667 * for the interpreter happens in the namespace of the
668 * to-be-execed image. SET_PERSONALITY can select an
669 * alternate root.
670 *
671 * However, SET_PERSONALITY is NOT allowed to switch
672 * this task into the new images's memory mapping
673 * policy - that is, TASK_SIZE must still evaluate to
674 * that which is appropriate to the execing application.
675 * This is because exit_mmap() needs to have TASK_SIZE
676 * evaluate to the size of the old image.
677 *
678 * So if (say) a 64-bit application is execing a 32-bit
679 * application it is the architecture's responsibility
680 * to defer changing the value of TASK_SIZE until the
681 * switch really is going to happen - do this in
682 * flush_thread(). - akpm
683 */
684 SET_PERSONALITY(loc->elf_ex);
685
686 interpreter = open_exec(elf_interpreter);
687 retval = PTR_ERR(interpreter);
688 if (IS_ERR(interpreter))
689 goto out_free_interp;
690
691 /*
692 * If the binary is not readable then enforce
693 * mm->dumpable = 0 regardless of the interpreter's
694 * permissions.
695 */
696 if (file_permission(interpreter, MAY_READ) < 0)
697 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
698
699 retval = kernel_read(interpreter, 0, bprm->buf,
700 BINPRM_BUF_SIZE);
701 if (retval != BINPRM_BUF_SIZE) {
702 if (retval >= 0)
703 retval = -EIO;
704 goto out_free_dentry;
705 }
706
707 /* Get the exec headers */
708 loc->interp_elf_ex = *((struct elfhdr *)bprm->buf);
709 break;
710 }
711 elf_ppnt++;
712 }
713
714 elf_ppnt = elf_phdata;
715 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
716 if (elf_ppnt->p_type == PT_GNU_STACK) {
717 if (elf_ppnt->p_flags & PF_X)
718 executable_stack = EXSTACK_ENABLE_X;
719 else
720 executable_stack = EXSTACK_DISABLE_X;
721 break;
722 }
723
724 /* Some simple consistency checks for the interpreter */
725 if (elf_interpreter) {
726 retval = -ELIBBAD;
727 /* Not an ELF interpreter */
728 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
729 goto out_free_dentry;
730 /* Verify the interpreter has a valid arch */
731 if (!elf_check_arch(&loc->interp_elf_ex))
732 goto out_free_dentry;
733 } else {
734 /* Executables without an interpreter also need a personality */
735 SET_PERSONALITY(loc->elf_ex);
736 }
737
738 /* Flush all traces of the currently running executable */
739 retval = flush_old_exec(bprm);
740 if (retval)
741 goto out_free_dentry;
742
743 /* OK, This is the point of no return */
744 current->flags &= ~PF_FORKNOEXEC;
745 current->mm->def_flags = def_flags;
746
747 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
748 may depend on the personality. */
749 SET_PERSONALITY(loc->elf_ex);
750 if (elf_read_implies_exec(loc->elf_ex, executable_stack))
751 current->personality |= READ_IMPLIES_EXEC;
752
753 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
754 current->flags |= PF_RANDOMIZE;
755 arch_pick_mmap_layout(current->mm);
756
757 /* Do this so that we can load the interpreter, if need be. We will
758 change some of these later */
759 current->mm->free_area_cache = current->mm->mmap_base;
760 current->mm->cached_hole_size = 0;
761 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
762 executable_stack);
763 if (retval < 0) {
764 send_sig(SIGKILL, current, 0);
765 goto out_free_dentry;
766 }
767
768 current->mm->start_stack = bprm->p;
769
770 /* Now we do a little grungy work by mmapping the ELF image into
771 the correct location in memory. */
772 for(i = 0, elf_ppnt = elf_phdata;
773 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
774 int elf_prot = 0, elf_flags;
775 unsigned long k, vaddr;
776
777 if (elf_ppnt->p_type != PT_LOAD)
778 continue;
779
780 if (unlikely (elf_brk > elf_bss)) {
781 unsigned long nbyte;
782
783 /* There was a PT_LOAD segment with p_memsz > p_filesz
784 before this one. Map anonymous pages, if needed,
785 and clear the area. */
786 retval = set_brk (elf_bss + load_bias,
787 elf_brk + load_bias);
788 if (retval) {
789 send_sig(SIGKILL, current, 0);
790 goto out_free_dentry;
791 }
792 nbyte = ELF_PAGEOFFSET(elf_bss);
793 if (nbyte) {
794 nbyte = ELF_MIN_ALIGN - nbyte;
795 if (nbyte > elf_brk - elf_bss)
796 nbyte = elf_brk - elf_bss;
797 if (clear_user((void __user *)elf_bss +
798 load_bias, nbyte)) {
799 /*
800 * This bss-zeroing can fail if the ELF
801 * file specifies odd protections. So
802 * we don't check the return value
803 */
804 }
805 }
806 }
807
808 if (elf_ppnt->p_flags & PF_R)
809 elf_prot |= PROT_READ;
810 if (elf_ppnt->p_flags & PF_W)
811 elf_prot |= PROT_WRITE;
812 if (elf_ppnt->p_flags & PF_X)
813 elf_prot |= PROT_EXEC;
814
815 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
816
817 vaddr = elf_ppnt->p_vaddr;
818 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
819 elf_flags |= MAP_FIXED;
820 } else if (loc->elf_ex.e_type == ET_DYN) {
821 /* Try and get dynamic programs out of the way of the
822 * default mmap base, as well as whatever program they
823 * might try to exec. This is because the brk will
824 * follow the loader, and is not movable. */
825 #ifdef CONFIG_X86
826 load_bias = 0;
827 #else
828 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
829 #endif
830 }
831
832 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
833 elf_prot, elf_flags, 0);
834 if (BAD_ADDR(error)) {
835 send_sig(SIGKILL, current, 0);
836 retval = IS_ERR((void *)error) ?
837 PTR_ERR((void*)error) : -EINVAL;
838 goto out_free_dentry;
839 }
840
841 if (!load_addr_set) {
842 load_addr_set = 1;
843 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
844 if (loc->elf_ex.e_type == ET_DYN) {
845 load_bias += error -
846 ELF_PAGESTART(load_bias + vaddr);
847 load_addr += load_bias;
848 reloc_func_desc = load_bias;
849 }
850 }
851 k = elf_ppnt->p_vaddr;
852 if (k < start_code)
853 start_code = k;
854 if (start_data < k)
855 start_data = k;
856
857 /*
858 * Check to see if the section's size will overflow the
859 * allowed task size. Note that p_filesz must always be
860 * <= p_memsz so it is only necessary to check p_memsz.
861 */
862 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
863 elf_ppnt->p_memsz > TASK_SIZE ||
864 TASK_SIZE - elf_ppnt->p_memsz < k) {
865 /* set_brk can never work. Avoid overflows. */
866 send_sig(SIGKILL, current, 0);
867 retval = -EINVAL;
868 goto out_free_dentry;
869 }
870
871 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
872
873 if (k > elf_bss)
874 elf_bss = k;
875 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
876 end_code = k;
877 if (end_data < k)
878 end_data = k;
879 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
880 if (k > elf_brk)
881 elf_brk = k;
882 }
883
884 loc->elf_ex.e_entry += load_bias;
885 elf_bss += load_bias;
886 elf_brk += load_bias;
887 start_code += load_bias;
888 end_code += load_bias;
889 start_data += load_bias;
890 end_data += load_bias;
891
892 /* Calling set_brk effectively mmaps the pages that we need
893 * for the bss and break sections. We must do this before
894 * mapping in the interpreter, to make sure it doesn't wind
895 * up getting placed where the bss needs to go.
896 */
897 retval = set_brk(elf_bss, elf_brk);
898 if (retval) {
899 send_sig(SIGKILL, current, 0);
900 goto out_free_dentry;
901 }
902 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
903 send_sig(SIGSEGV, current, 0);
904 retval = -EFAULT; /* Nobody gets to see this, but.. */
905 goto out_free_dentry;
906 }
907
908 if (elf_interpreter) {
909 unsigned long uninitialized_var(interp_map_addr);
910
911 elf_entry = load_elf_interp(&loc->interp_elf_ex,
912 interpreter,
913 &interp_map_addr,
914 load_bias);
915 if (!IS_ERR((void *)elf_entry)) {
916 /*
917 * load_elf_interp() returns relocation
918 * adjustment
919 */
920 interp_load_addr = elf_entry;
921 elf_entry += loc->interp_elf_ex.e_entry;
922 }
923 if (BAD_ADDR(elf_entry)) {
924 force_sig(SIGSEGV, current);
925 retval = IS_ERR((void *)elf_entry) ?
926 (int)elf_entry : -EINVAL;
927 goto out_free_dentry;
928 }
929 reloc_func_desc = interp_load_addr;
930
931 allow_write_access(interpreter);
932 fput(interpreter);
933 kfree(elf_interpreter);
934 } else {
935 elf_entry = loc->elf_ex.e_entry;
936 if (BAD_ADDR(elf_entry)) {
937 force_sig(SIGSEGV, current);
938 retval = -EINVAL;
939 goto out_free_dentry;
940 }
941 }
942
943 kfree(elf_phdata);
944
945 set_binfmt(&elf_format);
946
947 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
948 retval = arch_setup_additional_pages(bprm, !!elf_interpreter);
949 if (retval < 0) {
950 send_sig(SIGKILL, current, 0);
951 goto out;
952 }
953 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
954
955 install_exec_creds(bprm);
956 current->flags &= ~PF_FORKNOEXEC;
957 retval = create_elf_tables(bprm, &loc->elf_ex,
958 load_addr, interp_load_addr);
959 if (retval < 0) {
960 send_sig(SIGKILL, current, 0);
961 goto out;
962 }
963 /* N.B. passed_fileno might not be initialized? */
964 current->mm->end_code = end_code;
965 current->mm->start_code = start_code;
966 current->mm->start_data = start_data;
967 current->mm->end_data = end_data;
968 current->mm->start_stack = bprm->p;
969
970 #ifdef arch_randomize_brk
971 if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1))
972 current->mm->brk = current->mm->start_brk =
973 arch_randomize_brk(current->mm);
974 #endif
975
976 if (current->personality & MMAP_PAGE_ZERO) {
977 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
978 and some applications "depend" upon this behavior.
979 Since we do not have the power to recompile these, we
980 emulate the SVr4 behavior. Sigh. */
981 down_write(&current->mm->mmap_sem);
982 error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
983 MAP_FIXED | MAP_PRIVATE, 0);
984 up_write(&current->mm->mmap_sem);
985 }
986
987 #ifdef ELF_PLAT_INIT
988 /*
989 * The ABI may specify that certain registers be set up in special
990 * ways (on i386 %edx is the address of a DT_FINI function, for
991 * example. In addition, it may also specify (eg, PowerPC64 ELF)
992 * that the e_entry field is the address of the function descriptor
993 * for the startup routine, rather than the address of the startup
994 * routine itself. This macro performs whatever initialization to
995 * the regs structure is required as well as any relocations to the
996 * function descriptor entries when executing dynamically links apps.
997 */
998 ELF_PLAT_INIT(regs, reloc_func_desc);
999 #endif
1000
1001 start_thread(regs, elf_entry, bprm->p);
1002 retval = 0;
1003 out:
1004 kfree(loc);
1005 out_ret:
1006 return retval;
1007
1008 /* error cleanup */
1009 out_free_dentry:
1010 allow_write_access(interpreter);
1011 if (interpreter)
1012 fput(interpreter);
1013 out_free_interp:
1014 kfree(elf_interpreter);
1015 out_free_ph:
1016 kfree(elf_phdata);
1017 goto out;
1018 }
1019
1020 /* This is really simpleminded and specialized - we are loading an
1021 a.out library that is given an ELF header. */
1022 static int load_elf_library(struct file *file)
1023 {
1024 struct elf_phdr *elf_phdata;
1025 struct elf_phdr *eppnt;
1026 unsigned long elf_bss, bss, len;
1027 int retval, error, i, j;
1028 struct elfhdr elf_ex;
1029
1030 error = -ENOEXEC;
1031 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
1032 if (retval != sizeof(elf_ex))
1033 goto out;
1034
1035 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
1036 goto out;
1037
1038 /* First of all, some simple consistency checks */
1039 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
1040 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
1041 goto out;
1042
1043 /* Now read in all of the header information */
1044
1045 j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
1046 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1047
1048 error = -ENOMEM;
1049 elf_phdata = kmalloc(j, GFP_KERNEL);
1050 if (!elf_phdata)
1051 goto out;
1052
1053 eppnt = elf_phdata;
1054 error = -ENOEXEC;
1055 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
1056 if (retval != j)
1057 goto out_free_ph;
1058
1059 for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
1060 if ((eppnt + i)->p_type == PT_LOAD)
1061 j++;
1062 if (j != 1)
1063 goto out_free_ph;
1064
1065 while (eppnt->p_type != PT_LOAD)
1066 eppnt++;
1067
1068 /* Now use mmap to map the library into memory. */
1069 down_write(&current->mm->mmap_sem);
1070 error = do_mmap(file,
1071 ELF_PAGESTART(eppnt->p_vaddr),
1072 (eppnt->p_filesz +
1073 ELF_PAGEOFFSET(eppnt->p_vaddr)),
1074 PROT_READ | PROT_WRITE | PROT_EXEC,
1075 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
1076 (eppnt->p_offset -
1077 ELF_PAGEOFFSET(eppnt->p_vaddr)));
1078 up_write(&current->mm->mmap_sem);
1079 if (error != ELF_PAGESTART(eppnt->p_vaddr))
1080 goto out_free_ph;
1081
1082 elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
1083 if (padzero(elf_bss)) {
1084 error = -EFAULT;
1085 goto out_free_ph;
1086 }
1087
1088 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
1089 ELF_MIN_ALIGN - 1);
1090 bss = eppnt->p_memsz + eppnt->p_vaddr;
1091 if (bss > len) {
1092 down_write(&current->mm->mmap_sem);
1093 do_brk(len, bss - len);
1094 up_write(&current->mm->mmap_sem);
1095 }
1096 error = 0;
1097
1098 out_free_ph:
1099 kfree(elf_phdata);
1100 out:
1101 return error;
1102 }
1103
1104 #ifdef CONFIG_ELF_CORE
1105 /*
1106 * ELF core dumper
1107 *
1108 * Modelled on fs/exec.c:aout_core_dump()
1109 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1110 */
1111 /*
1112 * These are the only things you should do on a core-file: use only these
1113 * functions to write out all the necessary info.
1114 */
1115 static int dump_write(struct file *file, const void *addr, int nr)
1116 {
1117 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
1118 }
1119
1120 static int dump_seek(struct file *file, loff_t off)
1121 {
1122 if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
1123 if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
1124 return 0;
1125 } else {
1126 char *buf = (char *)get_zeroed_page(GFP_KERNEL);
1127 if (!buf)
1128 return 0;
1129 while (off > 0) {
1130 unsigned long n = off;
1131 if (n > PAGE_SIZE)
1132 n = PAGE_SIZE;
1133 if (!dump_write(file, buf, n))
1134 return 0;
1135 off -= n;
1136 }
1137 free_page((unsigned long)buf);
1138 }
1139 return 1;
1140 }
1141
1142 /*
1143 * Decide what to dump of a segment, part, all or none.
1144 */
1145 static unsigned long vma_dump_size(struct vm_area_struct *vma,
1146 unsigned long mm_flags)
1147 {
1148 #define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1149
1150 /* The vma can be set up to tell us the answer directly. */
1151 if (vma->vm_flags & VM_ALWAYSDUMP)
1152 goto whole;
1153
1154 /* Hugetlb memory check */
1155 if (vma->vm_flags & VM_HUGETLB) {
1156 if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
1157 goto whole;
1158 if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
1159 goto whole;
1160 }
1161
1162 /* Do not dump I/O mapped devices or special mappings */
1163 if (vma->vm_flags & (VM_IO | VM_RESERVED))
1164 return 0;
1165
1166 /* By default, dump shared memory if mapped from an anonymous file. */
1167 if (vma->vm_flags & VM_SHARED) {
1168 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ?
1169 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
1170 goto whole;
1171 return 0;
1172 }
1173
1174 /* Dump segments that have been written to. */
1175 if (vma->anon_vma && FILTER(ANON_PRIVATE))
1176 goto whole;
1177 if (vma->vm_file == NULL)
1178 return 0;
1179
1180 if (FILTER(MAPPED_PRIVATE))
1181 goto whole;
1182
1183 /*
1184 * If this looks like the beginning of a DSO or executable mapping,
1185 * check for an ELF header. If we find one, dump the first page to
1186 * aid in determining what was mapped here.
1187 */
1188 if (FILTER(ELF_HEADERS) &&
1189 vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
1190 u32 __user *header = (u32 __user *) vma->vm_start;
1191 u32 word;
1192 mm_segment_t fs = get_fs();
1193 /*
1194 * Doing it this way gets the constant folded by GCC.
1195 */
1196 union {
1197 u32 cmp;
1198 char elfmag[SELFMAG];
1199 } magic;
1200 BUILD_BUG_ON(SELFMAG != sizeof word);
1201 magic.elfmag[EI_MAG0] = ELFMAG0;
1202 magic.elfmag[EI_MAG1] = ELFMAG1;
1203 magic.elfmag[EI_MAG2] = ELFMAG2;
1204 magic.elfmag[EI_MAG3] = ELFMAG3;
1205 /*
1206 * Switch to the user "segment" for get_user(),
1207 * then put back what elf_core_dump() had in place.
1208 */
1209 set_fs(USER_DS);
1210 if (unlikely(get_user(word, header)))
1211 word = 0;
1212 set_fs(fs);
1213 if (word == magic.cmp)
1214 return PAGE_SIZE;
1215 }
1216
1217 #undef FILTER
1218
1219 return 0;
1220
1221 whole:
1222 return vma->vm_end - vma->vm_start;
1223 }
1224
1225 /* An ELF note in memory */
1226 struct memelfnote
1227 {
1228 const char *name;
1229 int type;
1230 unsigned int datasz;
1231 void *data;
1232 };
1233
1234 static int notesize(struct memelfnote *en)
1235 {
1236 int sz;
1237
1238 sz = sizeof(struct elf_note);
1239 sz += roundup(strlen(en->name) + 1, 4);
1240 sz += roundup(en->datasz, 4);
1241
1242 return sz;
1243 }
1244
1245 #define DUMP_WRITE(addr, nr, foffset) \
1246 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
1247
1248 static int alignfile(struct file *file, loff_t *foffset)
1249 {
1250 static const char buf[4] = { 0, };
1251 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
1252 return 1;
1253 }
1254
1255 static int writenote(struct memelfnote *men, struct file *file,
1256 loff_t *foffset)
1257 {
1258 struct elf_note en;
1259 en.n_namesz = strlen(men->name) + 1;
1260 en.n_descsz = men->datasz;
1261 en.n_type = men->type;
1262
1263 DUMP_WRITE(&en, sizeof(en), foffset);
1264 DUMP_WRITE(men->name, en.n_namesz, foffset);
1265 if (!alignfile(file, foffset))
1266 return 0;
1267 DUMP_WRITE(men->data, men->datasz, foffset);
1268 if (!alignfile(file, foffset))
1269 return 0;
1270
1271 return 1;
1272 }
1273 #undef DUMP_WRITE
1274
1275 #define DUMP_WRITE(addr, nr) \
1276 if ((size += (nr)) > cprm->limit || \
1277 !dump_write(cprm->file, (addr), (nr))) \
1278 goto end_coredump;
1279
1280 static void fill_elf_header(struct elfhdr *elf, int segs,
1281 u16 machine, u32 flags, u8 osabi)
1282 {
1283 memset(elf, 0, sizeof(*elf));
1284
1285 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1286 elf->e_ident[EI_CLASS] = ELF_CLASS;
1287 elf->e_ident[EI_DATA] = ELF_DATA;
1288 elf->e_ident[EI_VERSION] = EV_CURRENT;
1289 elf->e_ident[EI_OSABI] = ELF_OSABI;
1290
1291 elf->e_type = ET_CORE;
1292 elf->e_machine = machine;
1293 elf->e_version = EV_CURRENT;
1294 elf->e_phoff = sizeof(struct elfhdr);
1295 elf->e_flags = flags;
1296 elf->e_ehsize = sizeof(struct elfhdr);
1297 elf->e_phentsize = sizeof(struct elf_phdr);
1298 elf->e_phnum = segs;
1299
1300 return;
1301 }
1302
1303 static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
1304 {
1305 phdr->p_type = PT_NOTE;
1306 phdr->p_offset = offset;
1307 phdr->p_vaddr = 0;
1308 phdr->p_paddr = 0;
1309 phdr->p_filesz = sz;
1310 phdr->p_memsz = 0;
1311 phdr->p_flags = 0;
1312 phdr->p_align = 0;
1313 return;
1314 }
1315
1316 static void fill_note(struct memelfnote *note, const char *name, int type,
1317 unsigned int sz, void *data)
1318 {
1319 note->name = name;
1320 note->type = type;
1321 note->datasz = sz;
1322 note->data = data;
1323 return;
1324 }
1325
1326 /*
1327 * fill up all the fields in prstatus from the given task struct, except
1328 * registers which need to be filled up separately.
1329 */
1330 static void fill_prstatus(struct elf_prstatus *prstatus,
1331 struct task_struct *p, long signr)
1332 {
1333 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1334 prstatus->pr_sigpend = p->pending.signal.sig[0];
1335 prstatus->pr_sighold = p->blocked.sig[0];
1336 rcu_read_lock();
1337 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1338 rcu_read_unlock();
1339 prstatus->pr_pid = task_pid_vnr(p);
1340 prstatus->pr_pgrp = task_pgrp_vnr(p);
1341 prstatus->pr_sid = task_session_vnr(p);
1342 if (thread_group_leader(p)) {
1343 struct task_cputime cputime;
1344
1345 /*
1346 * This is the record for the group leader. It shows the
1347 * group-wide total, not its individual thread total.
1348 */
1349 thread_group_cputime(p, &cputime);
1350 cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
1351 cputime_to_timeval(cputime.stime, &prstatus->pr_stime);
1352 } else {
1353 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1354 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1355 }
1356 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1357 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1358 }
1359
1360 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1361 struct mm_struct *mm)
1362 {
1363 const struct cred *cred;
1364 unsigned int i, len;
1365
1366 /* first copy the parameters from user space */
1367 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1368
1369 len = mm->arg_end - mm->arg_start;
1370 if (len >= ELF_PRARGSZ)
1371 len = ELF_PRARGSZ-1;
1372 if (copy_from_user(&psinfo->pr_psargs,
1373 (const char __user *)mm->arg_start, len))
1374 return -EFAULT;
1375 for(i = 0; i < len; i++)
1376 if (psinfo->pr_psargs[i] == 0)
1377 psinfo->pr_psargs[i] = ' ';
1378 psinfo->pr_psargs[len] = 0;
1379
1380 rcu_read_lock();
1381 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1382 rcu_read_unlock();
1383 psinfo->pr_pid = task_pid_vnr(p);
1384 psinfo->pr_pgrp = task_pgrp_vnr(p);
1385 psinfo->pr_sid = task_session_vnr(p);
1386
1387 i = p->state ? ffz(~p->state) + 1 : 0;
1388 psinfo->pr_state = i;
1389 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
1390 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1391 psinfo->pr_nice = task_nice(p);
1392 psinfo->pr_flag = p->flags;
1393 rcu_read_lock();
1394 cred = __task_cred(p);
1395 SET_UID(psinfo->pr_uid, cred->uid);
1396 SET_GID(psinfo->pr_gid, cred->gid);
1397 rcu_read_unlock();
1398 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1399
1400 return 0;
1401 }
1402
1403 static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
1404 {
1405 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
1406 int i = 0;
1407 do
1408 i += 2;
1409 while (auxv[i - 2] != AT_NULL);
1410 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
1411 }
1412
1413 #ifdef CORE_DUMP_USE_REGSET
1414 #include <linux/regset.h>
1415
1416 struct elf_thread_core_info {
1417 struct elf_thread_core_info *next;
1418 struct task_struct *task;
1419 struct elf_prstatus prstatus;
1420 struct memelfnote notes[0];
1421 };
1422
1423 struct elf_note_info {
1424 struct elf_thread_core_info *thread;
1425 struct memelfnote psinfo;
1426 struct memelfnote auxv;
1427 size_t size;
1428 int thread_notes;
1429 };
1430
1431 /*
1432 * When a regset has a writeback hook, we call it on each thread before
1433 * dumping user memory. On register window machines, this makes sure the
1434 * user memory backing the register data is up to date before we read it.
1435 */
1436 static void do_thread_regset_writeback(struct task_struct *task,
1437 const struct user_regset *regset)
1438 {
1439 if (regset->writeback)
1440 regset->writeback(task, regset, 1);
1441 }
1442
1443 static int fill_thread_core_info(struct elf_thread_core_info *t,
1444 const struct user_regset_view *view,
1445 long signr, size_t *total)
1446 {
1447 unsigned int i;
1448
1449 /*
1450 * NT_PRSTATUS is the one special case, because the regset data
1451 * goes into the pr_reg field inside the note contents, rather
1452 * than being the whole note contents. We fill the reset in here.
1453 * We assume that regset 0 is NT_PRSTATUS.
1454 */
1455 fill_prstatus(&t->prstatus, t->task, signr);
1456 (void) view->regsets[0].get(t->task, &view->regsets[0],
1457 0, sizeof(t->prstatus.pr_reg),
1458 &t->prstatus.pr_reg, NULL);
1459
1460 fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
1461 sizeof(t->prstatus), &t->prstatus);
1462 *total += notesize(&t->notes[0]);
1463
1464 do_thread_regset_writeback(t->task, &view->regsets[0]);
1465
1466 /*
1467 * Each other regset might generate a note too. For each regset
1468 * that has no core_note_type or is inactive, we leave t->notes[i]
1469 * all zero and we'll know to skip writing it later.
1470 */
1471 for (i = 1; i < view->n; ++i) {
1472 const struct user_regset *regset = &view->regsets[i];
1473 do_thread_regset_writeback(t->task, regset);
1474 if (regset->core_note_type &&
1475 (!regset->active || regset->active(t->task, regset))) {
1476 int ret;
1477 size_t size = regset->n * regset->size;
1478 void *data = kmalloc(size, GFP_KERNEL);
1479 if (unlikely(!data))
1480 return 0;
1481 ret = regset->get(t->task, regset,
1482 0, size, data, NULL);
1483 if (unlikely(ret))
1484 kfree(data);
1485 else {
1486 if (regset->core_note_type != NT_PRFPREG)
1487 fill_note(&t->notes[i], "LINUX",
1488 regset->core_note_type,
1489 size, data);
1490 else {
1491 t->prstatus.pr_fpvalid = 1;
1492 fill_note(&t->notes[i], "CORE",
1493 NT_PRFPREG, size, data);
1494 }
1495 *total += notesize(&t->notes[i]);
1496 }
1497 }
1498 }
1499
1500 return 1;
1501 }
1502
1503 static int fill_note_info(struct elfhdr *elf, int phdrs,
1504 struct elf_note_info *info,
1505 long signr, struct pt_regs *regs)
1506 {
1507 struct task_struct *dump_task = current;
1508 const struct user_regset_view *view = task_user_regset_view(dump_task);
1509 struct elf_thread_core_info *t;
1510 struct elf_prpsinfo *psinfo;
1511 struct core_thread *ct;
1512 unsigned int i;
1513
1514 info->size = 0;
1515 info->thread = NULL;
1516
1517 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1518 if (psinfo == NULL)
1519 return 0;
1520
1521 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1522
1523 /*
1524 * Figure out how many notes we're going to need for each thread.
1525 */
1526 info->thread_notes = 0;
1527 for (i = 0; i < view->n; ++i)
1528 if (view->regsets[i].core_note_type != 0)
1529 ++info->thread_notes;
1530
1531 /*
1532 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1533 * since it is our one special case.
1534 */
1535 if (unlikely(info->thread_notes == 0) ||
1536 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
1537 WARN_ON(1);
1538 return 0;
1539 }
1540
1541 /*
1542 * Initialize the ELF file header.
1543 */
1544 fill_elf_header(elf, phdrs,
1545 view->e_machine, view->e_flags, view->ei_osabi);
1546
1547 /*
1548 * Allocate a structure for each thread.
1549 */
1550 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) {
1551 t = kzalloc(offsetof(struct elf_thread_core_info,
1552 notes[info->thread_notes]),
1553 GFP_KERNEL);
1554 if (unlikely(!t))
1555 return 0;
1556
1557 t->task = ct->task;
1558 if (ct->task == dump_task || !info->thread) {
1559 t->next = info->thread;
1560 info->thread = t;
1561 } else {
1562 /*
1563 * Make sure to keep the original task at
1564 * the head of the list.
1565 */
1566 t->next = info->thread->next;
1567 info->thread->next = t;
1568 }
1569 }
1570
1571 /*
1572 * Now fill in each thread's information.
1573 */
1574 for (t = info->thread; t != NULL; t = t->next)
1575 if (!fill_thread_core_info(t, view, signr, &info->size))
1576 return 0;
1577
1578 /*
1579 * Fill in the two process-wide notes.
1580 */
1581 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
1582 info->size += notesize(&info->psinfo);
1583
1584 fill_auxv_note(&info->auxv, current->mm);
1585 info->size += notesize(&info->auxv);
1586
1587 return 1;
1588 }
1589
1590 static size_t get_note_info_size(struct elf_note_info *info)
1591 {
1592 return info->size;
1593 }
1594
1595 /*
1596 * Write all the notes for each thread. When writing the first thread, the
1597 * process-wide notes are interleaved after the first thread-specific note.
1598 */
1599 static int write_note_info(struct elf_note_info *info,
1600 struct file *file, loff_t *foffset)
1601 {
1602 bool first = 1;
1603 struct elf_thread_core_info *t = info->thread;
1604
1605 do {
1606 int i;
1607
1608 if (!writenote(&t->notes[0], file, foffset))
1609 return 0;
1610
1611 if (first && !writenote(&info->psinfo, file, foffset))
1612 return 0;
1613 if (first && !writenote(&info->auxv, file, foffset))
1614 return 0;
1615
1616 for (i = 1; i < info->thread_notes; ++i)
1617 if (t->notes[i].data &&
1618 !writenote(&t->notes[i], file, foffset))
1619 return 0;
1620
1621 first = 0;
1622 t = t->next;
1623 } while (t);
1624
1625 return 1;
1626 }
1627
1628 static void free_note_info(struct elf_note_info *info)
1629 {
1630 struct elf_thread_core_info *threads = info->thread;
1631 while (threads) {
1632 unsigned int i;
1633 struct elf_thread_core_info *t = threads;
1634 threads = t->next;
1635 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
1636 for (i = 1; i < info->thread_notes; ++i)
1637 kfree(t->notes[i].data);
1638 kfree(t);
1639 }
1640 kfree(info->psinfo.data);
1641 }
1642
1643 #else
1644
1645 /* Here is the structure in which status of each thread is captured. */
1646 struct elf_thread_status
1647 {
1648 struct list_head list;
1649 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1650 elf_fpregset_t fpu; /* NT_PRFPREG */
1651 struct task_struct *thread;
1652 #ifdef ELF_CORE_COPY_XFPREGS
1653 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
1654 #endif
1655 struct memelfnote notes[3];
1656 int num_notes;
1657 };
1658
1659 /*
1660 * In order to add the specific thread information for the elf file format,
1661 * we need to keep a linked list of every threads pr_status and then create
1662 * a single section for them in the final core file.
1663 */
1664 static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1665 {
1666 int sz = 0;
1667 struct task_struct *p = t->thread;
1668 t->num_notes = 0;
1669
1670 fill_prstatus(&t->prstatus, p, signr);
1671 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1672
1673 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1674 &(t->prstatus));
1675 t->num_notes++;
1676 sz += notesize(&t->notes[0]);
1677
1678 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1679 &t->fpu))) {
1680 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1681 &(t->fpu));
1682 t->num_notes++;
1683 sz += notesize(&t->notes[1]);
1684 }
1685
1686 #ifdef ELF_CORE_COPY_XFPREGS
1687 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
1688 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1689 sizeof(t->xfpu), &t->xfpu);
1690 t->num_notes++;
1691 sz += notesize(&t->notes[2]);
1692 }
1693 #endif
1694 return sz;
1695 }
1696
1697 struct elf_note_info {
1698 struct memelfnote *notes;
1699 struct elf_prstatus *prstatus; /* NT_PRSTATUS */
1700 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */
1701 struct list_head thread_list;
1702 elf_fpregset_t *fpu;
1703 #ifdef ELF_CORE_COPY_XFPREGS
1704 elf_fpxregset_t *xfpu;
1705 #endif
1706 int thread_status_size;
1707 int numnote;
1708 };
1709
1710 static int elf_note_info_init(struct elf_note_info *info)
1711 {
1712 memset(info, 0, sizeof(*info));
1713 INIT_LIST_HEAD(&info->thread_list);
1714
1715 /* Allocate space for six ELF notes */
1716 info->notes = kmalloc(6 * sizeof(struct memelfnote), GFP_KERNEL);
1717 if (!info->notes)
1718 return 0;
1719 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
1720 if (!info->psinfo)
1721 goto notes_free;
1722 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
1723 if (!info->prstatus)
1724 goto psinfo_free;
1725 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
1726 if (!info->fpu)
1727 goto prstatus_free;
1728 #ifdef ELF_CORE_COPY_XFPREGS
1729 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
1730 if (!info->xfpu)
1731 goto fpu_free;
1732 #endif
1733 return 1;
1734 #ifdef ELF_CORE_COPY_XFPREGS
1735 fpu_free:
1736 kfree(info->fpu);
1737 #endif
1738 prstatus_free:
1739 kfree(info->prstatus);
1740 psinfo_free:
1741 kfree(info->psinfo);
1742 notes_free:
1743 kfree(info->notes);
1744 return 0;
1745 }
1746
1747 static int fill_note_info(struct elfhdr *elf, int phdrs,
1748 struct elf_note_info *info,
1749 long signr, struct pt_regs *regs)
1750 {
1751 struct list_head *t;
1752
1753 if (!elf_note_info_init(info))
1754 return 0;
1755
1756 if (signr) {
1757 struct core_thread *ct;
1758 struct elf_thread_status *ets;
1759
1760 for (ct = current->mm->core_state->dumper.next;
1761 ct; ct = ct->next) {
1762 ets = kzalloc(sizeof(*ets), GFP_KERNEL);
1763 if (!ets)
1764 return 0;
1765
1766 ets->thread = ct->task;
1767 list_add(&ets->list, &info->thread_list);
1768 }
1769
1770 list_for_each(t, &info->thread_list) {
1771 int sz;
1772
1773 ets = list_entry(t, struct elf_thread_status, list);
1774 sz = elf_dump_thread_status(signr, ets);
1775 info->thread_status_size += sz;
1776 }
1777 }
1778 /* now collect the dump for the current */
1779 memset(info->prstatus, 0, sizeof(*info->prstatus));
1780 fill_prstatus(info->prstatus, current, signr);
1781 elf_core_copy_regs(&info->prstatus->pr_reg, regs);
1782
1783 /* Set up header */
1784 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI);
1785
1786 /*
1787 * Set up the notes in similar form to SVR4 core dumps made
1788 * with info from their /proc.
1789 */
1790
1791 fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
1792 sizeof(*info->prstatus), info->prstatus);
1793 fill_psinfo(info->psinfo, current->group_leader, current->mm);
1794 fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
1795 sizeof(*info->psinfo), info->psinfo);
1796
1797 info->numnote = 2;
1798
1799 fill_auxv_note(&info->notes[info->numnote++], current->mm);
1800
1801 /* Try to dump the FPU. */
1802 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
1803 info->fpu);
1804 if (info->prstatus->pr_fpvalid)
1805 fill_note(info->notes + info->numnote++,
1806 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
1807 #ifdef ELF_CORE_COPY_XFPREGS
1808 if (elf_core_copy_task_xfpregs(current, info->xfpu))
1809 fill_note(info->notes + info->numnote++,
1810 "LINUX", ELF_CORE_XFPREG_TYPE,
1811 sizeof(*info->xfpu), info->xfpu);
1812 #endif
1813
1814 return 1;
1815 }
1816
1817 static size_t get_note_info_size(struct elf_note_info *info)
1818 {
1819 int sz = 0;
1820 int i;
1821
1822 for (i = 0; i < info->numnote; i++)
1823 sz += notesize(info->notes + i);
1824
1825 sz += info->thread_status_size;
1826
1827 return sz;
1828 }
1829
1830 static int write_note_info(struct elf_note_info *info,
1831 struct file *file, loff_t *foffset)
1832 {
1833 int i;
1834 struct list_head *t;
1835
1836 for (i = 0; i < info->numnote; i++)
1837 if (!writenote(info->notes + i, file, foffset))
1838 return 0;
1839
1840 /* write out the thread status notes section */
1841 list_for_each(t, &info->thread_list) {
1842 struct elf_thread_status *tmp =
1843 list_entry(t, struct elf_thread_status, list);
1844
1845 for (i = 0; i < tmp->num_notes; i++)
1846 if (!writenote(&tmp->notes[i], file, foffset))
1847 return 0;
1848 }
1849
1850 return 1;
1851 }
1852
1853 static void free_note_info(struct elf_note_info *info)
1854 {
1855 while (!list_empty(&info->thread_list)) {
1856 struct list_head *tmp = info->thread_list.next;
1857 list_del(tmp);
1858 kfree(list_entry(tmp, struct elf_thread_status, list));
1859 }
1860
1861 kfree(info->prstatus);
1862 kfree(info->psinfo);
1863 kfree(info->notes);
1864 kfree(info->fpu);
1865 #ifdef ELF_CORE_COPY_XFPREGS
1866 kfree(info->xfpu);
1867 #endif
1868 }
1869
1870 #endif
1871
1872 static struct vm_area_struct *first_vma(struct task_struct *tsk,
1873 struct vm_area_struct *gate_vma)
1874 {
1875 struct vm_area_struct *ret = tsk->mm->mmap;
1876
1877 if (ret)
1878 return ret;
1879 return gate_vma;
1880 }
1881 /*
1882 * Helper function for iterating across a vma list. It ensures that the caller
1883 * will visit `gate_vma' prior to terminating the search.
1884 */
1885 static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma,
1886 struct vm_area_struct *gate_vma)
1887 {
1888 struct vm_area_struct *ret;
1889
1890 ret = this_vma->vm_next;
1891 if (ret)
1892 return ret;
1893 if (this_vma == gate_vma)
1894 return NULL;
1895 return gate_vma;
1896 }
1897
1898 /*
1899 * Actual dumper
1900 *
1901 * This is a two-pass process; first we find the offsets of the bits,
1902 * and then they are actually written out. If we run out of core limit
1903 * we just truncate.
1904 */
1905 static int elf_core_dump(struct coredump_params *cprm)
1906 {
1907 int has_dumped = 0;
1908 mm_segment_t fs;
1909 int segs;
1910 size_t size = 0;
1911 struct vm_area_struct *vma, *gate_vma;
1912 struct elfhdr *elf = NULL;
1913 loff_t offset = 0, dataoff, foffset;
1914 unsigned long mm_flags;
1915 struct elf_note_info info;
1916
1917 /*
1918 * We no longer stop all VM operations.
1919 *
1920 * This is because those proceses that could possibly change map_count
1921 * or the mmap / vma pages are now blocked in do_exit on current
1922 * finishing this core dump.
1923 *
1924 * Only ptrace can touch these memory addresses, but it doesn't change
1925 * the map_count or the pages allocated. So no possibility of crashing
1926 * exists while dumping the mm->vm_next areas to the core file.
1927 */
1928
1929 /* alloc memory for large data structures: too large to be on stack */
1930 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1931 if (!elf)
1932 goto out;
1933 /*
1934 * The number of segs are recored into ELF header as 16bit value.
1935 * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
1936 */
1937 segs = current->mm->map_count;
1938 #ifdef ELF_CORE_EXTRA_PHDRS
1939 segs += ELF_CORE_EXTRA_PHDRS;
1940 #endif
1941
1942 gate_vma = get_gate_vma(current);
1943 if (gate_vma != NULL)
1944 segs++;
1945
1946 /*
1947 * Collect all the non-memory information about the process for the
1948 * notes. This also sets up the file header.
1949 */
1950 if (!fill_note_info(elf, segs + 1, /* including notes section */
1951 &info, cprm->signr, cprm->regs))
1952 goto cleanup;
1953
1954 has_dumped = 1;
1955 current->flags |= PF_DUMPCORE;
1956
1957 fs = get_fs();
1958 set_fs(KERNEL_DS);
1959
1960 DUMP_WRITE(elf, sizeof(*elf));
1961 offset += sizeof(*elf); /* Elf header */
1962 offset += (segs + 1) * sizeof(struct elf_phdr); /* Program headers */
1963 foffset = offset;
1964
1965 /* Write notes phdr entry */
1966 {
1967 struct elf_phdr phdr;
1968 size_t sz = get_note_info_size(&info);
1969
1970 sz += elf_coredump_extra_notes_size();
1971
1972 fill_elf_note_phdr(&phdr, sz, offset);
1973 offset += sz;
1974 DUMP_WRITE(&phdr, sizeof(phdr));
1975 }
1976
1977 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1978
1979 /*
1980 * We must use the same mm->flags while dumping core to avoid
1981 * inconsistency between the program headers and bodies, otherwise an
1982 * unusable core file can be generated.
1983 */
1984 mm_flags = current->mm->flags;
1985
1986 /* Write program headers for segments dump */
1987 for (vma = first_vma(current, gate_vma); vma != NULL;
1988 vma = next_vma(vma, gate_vma)) {
1989 struct elf_phdr phdr;
1990
1991 phdr.p_type = PT_LOAD;
1992 phdr.p_offset = offset;
1993 phdr.p_vaddr = vma->vm_start;
1994 phdr.p_paddr = 0;
1995 phdr.p_filesz = vma_dump_size(vma, mm_flags);
1996 phdr.p_memsz = vma->vm_end - vma->vm_start;
1997 offset += phdr.p_filesz;
1998 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
1999 if (vma->vm_flags & VM_WRITE)
2000 phdr.p_flags |= PF_W;
2001 if (vma->vm_flags & VM_EXEC)
2002 phdr.p_flags |= PF_X;
2003 phdr.p_align = ELF_EXEC_PAGESIZE;
2004
2005 DUMP_WRITE(&phdr, sizeof(phdr));
2006 }
2007
2008 #ifdef ELF_CORE_WRITE_EXTRA_PHDRS
2009 ELF_CORE_WRITE_EXTRA_PHDRS;
2010 #endif
2011
2012 /* write out the notes section */
2013 if (!write_note_info(&info, cprm->file, &foffset))
2014 goto end_coredump;
2015
2016 if (elf_coredump_extra_notes_write(cprm->file, &foffset))
2017 goto end_coredump;
2018
2019 /* Align to page */
2020 if (!dump_seek(cprm->file, dataoff - foffset))
2021 goto end_coredump;
2022
2023 for (vma = first_vma(current, gate_vma); vma != NULL;
2024 vma = next_vma(vma, gate_vma)) {
2025 unsigned long addr;
2026 unsigned long end;
2027
2028 end = vma->vm_start + vma_dump_size(vma, mm_flags);
2029
2030 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
2031 struct page *page;
2032 int stop;
2033
2034 page = get_dump_page(addr);
2035 if (page) {
2036 void *kaddr = kmap(page);
2037 stop = ((size += PAGE_SIZE) > cprm->limit) ||
2038 !dump_write(cprm->file, kaddr,
2039 PAGE_SIZE);
2040 kunmap(page);
2041 page_cache_release(page);
2042 } else
2043 stop = !dump_seek(cprm->file, PAGE_SIZE);
2044 if (stop)
2045 goto end_coredump;
2046 }
2047 }
2048
2049 #ifdef ELF_CORE_WRITE_EXTRA_DATA
2050 ELF_CORE_WRITE_EXTRA_DATA;
2051 #endif
2052
2053 end_coredump:
2054 set_fs(fs);
2055
2056 cleanup:
2057 free_note_info(&info);
2058 kfree(elf);
2059 out:
2060 return has_dumped;
2061 }
2062
2063 #endif /* CONFIG_ELF_CORE */
2064
2065 static int __init init_elf_binfmt(void)
2066 {
2067 return register_binfmt(&elf_format);
2068 }
2069
2070 static void __exit exit_elf_binfmt(void)
2071 {
2072 /* Remove the COFF and ELF loaders. */
2073 unregister_binfmt(&elf_format);
2074 }
2075
2076 core_initcall(init_elf_binfmt);
2077 module_exit(exit_elf_binfmt);
2078 MODULE_LICENSE("GPL");
Linux 2.6 libata-dev (mirror)