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bfs: assorted cleanups
[deliverable/linux.git] / fs / binfmt_elf.c
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/stat.h>
16 #include <linux/time.h>
17 #include <linux/mm.h>
18 #include <linux/mman.h>
19 #include <linux/errno.h>
20 #include <linux/signal.h>
21 #include <linux/binfmts.h>
22 #include <linux/string.h>
23 #include <linux/file.h>
24 #include <linux/fcntl.h>
25 #include <linux/ptrace.h>
26 #include <linux/slab.h>
27 #include <linux/shm.h>
28 #include <linux/personality.h>
29 #include <linux/elfcore.h>
30 #include <linux/init.h>
31 #include <linux/highuid.h>
32 #include <linux/smp.h>
33 #include <linux/compiler.h>
34 #include <linux/highmem.h>
35 #include <linux/pagemap.h>
36 #include <linux/security.h>
37 #include <linux/syscalls.h>
38 #include <linux/random.h>
39 #include <linux/elf.h>
40 #include <linux/utsname.h>
41 #include <asm/uaccess.h>
42 #include <asm/param.h>
43 #include <asm/page.h>
44
45 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs);
46 static int load_elf_library(struct file *);
47 static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *,
48 int, int, unsigned long);
49
50 /*
51 * If we don't support core dumping, then supply a NULL so we
52 * don't even try.
53 */
54 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
55 static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);
56 #else
57 #define elf_core_dump NULL
58 #endif
59
60 #if ELF_EXEC_PAGESIZE > PAGE_SIZE
61 #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
62 #else
63 #define ELF_MIN_ALIGN PAGE_SIZE
64 #endif
65
66 #ifndef ELF_CORE_EFLAGS
67 #define ELF_CORE_EFLAGS 0
68 #endif
69
70 #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
71 #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
72 #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
73
74 static struct linux_binfmt elf_format = {
75 .module = THIS_MODULE,
76 .load_binary = load_elf_binary,
77 .load_shlib = load_elf_library,
78 .core_dump = elf_core_dump,
79 .min_coredump = ELF_EXEC_PAGESIZE,
80 .hasvdso = 1
81 };
82
83 #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
84
85 static int set_brk(unsigned long start, unsigned long end)
86 {
87 start = ELF_PAGEALIGN(start);
88 end = ELF_PAGEALIGN(end);
89 if (end > start) {
90 unsigned long addr;
91 down_write(&current->mm->mmap_sem);
92 addr = do_brk(start, end - start);
93 up_write(&current->mm->mmap_sem);
94 if (BAD_ADDR(addr))
95 return addr;
96 }
97 current->mm->start_brk = current->mm->brk = end;
98 return 0;
99 }
100
101 /* We need to explicitly zero any fractional pages
102 after the data section (i.e. bss). This would
103 contain the junk from the file that should not
104 be in memory
105 */
106 static int padzero(unsigned long elf_bss)
107 {
108 unsigned long nbyte;
109
110 nbyte = ELF_PAGEOFFSET(elf_bss);
111 if (nbyte) {
112 nbyte = ELF_MIN_ALIGN - nbyte;
113 if (clear_user((void __user *) elf_bss, nbyte))
114 return -EFAULT;
115 }
116 return 0;
117 }
118
119 /* Let's use some macros to make this stack manipulation a little clearer */
120 #ifdef CONFIG_STACK_GROWSUP
121 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
122 #define STACK_ROUND(sp, items) \
123 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
124 #define STACK_ALLOC(sp, len) ({ \
125 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
126 old_sp; })
127 #else
128 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
129 #define STACK_ROUND(sp, items) \
130 (((unsigned long) (sp - items)) &~ 15UL)
131 #define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
132 #endif
133
134 #ifndef ELF_BASE_PLATFORM
135 /*
136 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
137 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
138 * will be copied to the user stack in the same manner as AT_PLATFORM.
139 */
140 #define ELF_BASE_PLATFORM NULL
141 #endif
142
143 static int
144 create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
145 unsigned long load_addr, unsigned long interp_load_addr)
146 {
147 unsigned long p = bprm->p;
148 int argc = bprm->argc;
149 int envc = bprm->envc;
150 elf_addr_t __user *argv;
151 elf_addr_t __user *envp;
152 elf_addr_t __user *sp;
153 elf_addr_t __user *u_platform;
154 elf_addr_t __user *u_base_platform;
155 const char *k_platform = ELF_PLATFORM;
156 const char *k_base_platform = ELF_BASE_PLATFORM;
157 int items;
158 elf_addr_t *elf_info;
159 int ei_index = 0;
160 struct task_struct *tsk = current;
161 struct vm_area_struct *vma;
162
163 /*
164 * In some cases (e.g. Hyper-Threading), we want to avoid L1
165 * evictions by the processes running on the same package. One
166 * thing we can do is to shuffle the initial stack for them.
167 */
168
169 p = arch_align_stack(p);
170
171 /*
172 * If this architecture has a platform capability string, copy it
173 * to userspace. In some cases (Sparc), this info is impossible
174 * for userspace to get any other way, in others (i386) it is
175 * merely difficult.
176 */
177 u_platform = NULL;
178 if (k_platform) {
179 size_t len = strlen(k_platform) + 1;
180
181 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
182 if (__copy_to_user(u_platform, k_platform, len))
183 return -EFAULT;
184 }
185
186 /*
187 * If this architecture has a "base" platform capability
188 * string, copy it to userspace.
189 */
190 u_base_platform = NULL;
191 if (k_base_platform) {
192 size_t len = strlen(k_base_platform) + 1;
193
194 u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
195 if (__copy_to_user(u_base_platform, k_base_platform, len))
196 return -EFAULT;
197 }
198
199 /* Create the ELF interpreter info */
200 elf_info = (elf_addr_t *)current->mm->saved_auxv;
201 /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
202 #define NEW_AUX_ENT(id, val) \
203 do { \
204 elf_info[ei_index++] = id; \
205 elf_info[ei_index++] = val; \
206 } while (0)
207
208 #ifdef ARCH_DLINFO
209 /*
210 * ARCH_DLINFO must come first so PPC can do its special alignment of
211 * AUXV.
212 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
213 * ARCH_DLINFO changes
214 */
215 ARCH_DLINFO;
216 #endif
217 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
218 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
219 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
220 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
221 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
222 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
223 NEW_AUX_ENT(AT_BASE, interp_load_addr);
224 NEW_AUX_ENT(AT_FLAGS, 0);
225 NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
226 NEW_AUX_ENT(AT_UID, tsk->uid);
227 NEW_AUX_ENT(AT_EUID, tsk->euid);
228 NEW_AUX_ENT(AT_GID, tsk->gid);
229 NEW_AUX_ENT(AT_EGID, tsk->egid);
230 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
231 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
232 if (k_platform) {
233 NEW_AUX_ENT(AT_PLATFORM,
234 (elf_addr_t)(unsigned long)u_platform);
235 }
236 if (k_base_platform) {
237 NEW_AUX_ENT(AT_BASE_PLATFORM,
238 (elf_addr_t)(unsigned long)u_base_platform);
239 }
240 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
241 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
242 }
243 #undef NEW_AUX_ENT
244 /* AT_NULL is zero; clear the rest too */
245 memset(&elf_info[ei_index], 0,
246 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
247
248 /* And advance past the AT_NULL entry. */
249 ei_index += 2;
250
251 sp = STACK_ADD(p, ei_index);
252
253 items = (argc + 1) + (envc + 1) + 1;
254 bprm->p = STACK_ROUND(sp, items);
255
256 /* Point sp at the lowest address on the stack */
257 #ifdef CONFIG_STACK_GROWSUP
258 sp = (elf_addr_t __user *)bprm->p - items - ei_index;
259 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
260 #else
261 sp = (elf_addr_t __user *)bprm->p;
262 #endif
263
264
265 /*
266 * Grow the stack manually; some architectures have a limit on how
267 * far ahead a user-space access may be in order to grow the stack.
268 */
269 vma = find_extend_vma(current->mm, bprm->p);
270 if (!vma)
271 return -EFAULT;
272
273 /* Now, let's put argc (and argv, envp if appropriate) on the stack */
274 if (__put_user(argc, sp++))
275 return -EFAULT;
276 argv = sp;
277 envp = argv + argc + 1;
278
279 /* Populate argv and envp */
280 p = current->mm->arg_end = current->mm->arg_start;
281 while (argc-- > 0) {
282 size_t len;
283 if (__put_user((elf_addr_t)p, argv++))
284 return -EFAULT;
285 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
286 if (!len || len > MAX_ARG_STRLEN)
287 return -EINVAL;
288 p += len;
289 }
290 if (__put_user(0, argv))
291 return -EFAULT;
292 current->mm->arg_end = current->mm->env_start = p;
293 while (envc-- > 0) {
294 size_t len;
295 if (__put_user((elf_addr_t)p, envp++))
296 return -EFAULT;
297 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
298 if (!len || len > MAX_ARG_STRLEN)
299 return -EINVAL;
300 p += len;
301 }
302 if (__put_user(0, envp))
303 return -EFAULT;
304 current->mm->env_end = p;
305
306 /* Put the elf_info on the stack in the right place. */
307 sp = (elf_addr_t __user *)envp + 1;
308 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
309 return -EFAULT;
310 return 0;
311 }
312
313 #ifndef elf_map
314
315 static unsigned long elf_map(struct file *filep, unsigned long addr,
316 struct elf_phdr *eppnt, int prot, int type,
317 unsigned long total_size)
318 {
319 unsigned long map_addr;
320 unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
321 unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
322 addr = ELF_PAGESTART(addr);
323 size = ELF_PAGEALIGN(size);
324
325 /* mmap() will return -EINVAL if given a zero size, but a
326 * segment with zero filesize is perfectly valid */
327 if (!size)
328 return addr;
329
330 down_write(&current->mm->mmap_sem);
331 /*
332 * total_size is the size of the ELF (interpreter) image.
333 * The _first_ mmap needs to know the full size, otherwise
334 * randomization might put this image into an overlapping
335 * position with the ELF binary image. (since size < total_size)
336 * So we first map the 'big' image - and unmap the remainder at
337 * the end. (which unmap is needed for ELF images with holes.)
338 */
339 if (total_size) {
340 total_size = ELF_PAGEALIGN(total_size);
341 map_addr = do_mmap(filep, addr, total_size, prot, type, off);
342 if (!BAD_ADDR(map_addr))
343 do_munmap(current->mm, map_addr+size, total_size-size);
344 } else
345 map_addr = do_mmap(filep, addr, size, prot, type, off);
346
347 up_write(&current->mm->mmap_sem);
348 return(map_addr);
349 }
350
351 #endif /* !elf_map */
352
353 static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr)
354 {
355 int i, first_idx = -1, last_idx = -1;
356
357 for (i = 0; i < nr; i++) {
358 if (cmds[i].p_type == PT_LOAD) {
359 last_idx = i;
360 if (first_idx == -1)
361 first_idx = i;
362 }
363 }
364 if (first_idx == -1)
365 return 0;
366
367 return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz -
368 ELF_PAGESTART(cmds[first_idx].p_vaddr);
369 }
370
371
372 /* This is much more generalized than the library routine read function,
373 so we keep this separate. Technically the library read function
374 is only provided so that we can read a.out libraries that have
375 an ELF header */
376
377 static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
378 struct file *interpreter, unsigned long *interp_map_addr,
379 unsigned long no_base)
380 {
381 struct elf_phdr *elf_phdata;
382 struct elf_phdr *eppnt;
383 unsigned long load_addr = 0;
384 int load_addr_set = 0;
385 unsigned long last_bss = 0, elf_bss = 0;
386 unsigned long error = ~0UL;
387 unsigned long total_size;
388 int retval, i, size;
389
390 /* First of all, some simple consistency checks */
391 if (interp_elf_ex->e_type != ET_EXEC &&
392 interp_elf_ex->e_type != ET_DYN)
393 goto out;
394 if (!elf_check_arch(interp_elf_ex))
395 goto out;
396 if (!interpreter->f_op || !interpreter->f_op->mmap)
397 goto out;
398
399 /*
400 * If the size of this structure has changed, then punt, since
401 * we will be doing the wrong thing.
402 */
403 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
404 goto out;
405 if (interp_elf_ex->e_phnum < 1 ||
406 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
407 goto out;
408
409 /* Now read in all of the header information */
410 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
411 if (size > ELF_MIN_ALIGN)
412 goto out;
413 elf_phdata = kmalloc(size, GFP_KERNEL);
414 if (!elf_phdata)
415 goto out;
416
417 retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
418 (char *)elf_phdata,size);
419 error = -EIO;
420 if (retval != size) {
421 if (retval < 0)
422 error = retval;
423 goto out_close;
424 }
425
426 total_size = total_mapping_size(elf_phdata, interp_elf_ex->e_phnum);
427 if (!total_size) {
428 error = -EINVAL;
429 goto out_close;
430 }
431
432 eppnt = elf_phdata;
433 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
434 if (eppnt->p_type == PT_LOAD) {
435 int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
436 int elf_prot = 0;
437 unsigned long vaddr = 0;
438 unsigned long k, map_addr;
439
440 if (eppnt->p_flags & PF_R)
441 elf_prot = PROT_READ;
442 if (eppnt->p_flags & PF_W)
443 elf_prot |= PROT_WRITE;
444 if (eppnt->p_flags & PF_X)
445 elf_prot |= PROT_EXEC;
446 vaddr = eppnt->p_vaddr;
447 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
448 elf_type |= MAP_FIXED;
449 else if (no_base && interp_elf_ex->e_type == ET_DYN)
450 load_addr = -vaddr;
451
452 map_addr = elf_map(interpreter, load_addr + vaddr,
453 eppnt, elf_prot, elf_type, total_size);
454 total_size = 0;
455 if (!*interp_map_addr)
456 *interp_map_addr = map_addr;
457 error = map_addr;
458 if (BAD_ADDR(map_addr))
459 goto out_close;
460
461 if (!load_addr_set &&
462 interp_elf_ex->e_type == ET_DYN) {
463 load_addr = map_addr - ELF_PAGESTART(vaddr);
464 load_addr_set = 1;
465 }
466
467 /*
468 * Check to see if the section's size will overflow the
469 * allowed task size. Note that p_filesz must always be
470 * <= p_memsize so it's only necessary to check p_memsz.
471 */
472 k = load_addr + eppnt->p_vaddr;
473 if (BAD_ADDR(k) ||
474 eppnt->p_filesz > eppnt->p_memsz ||
475 eppnt->p_memsz > TASK_SIZE ||
476 TASK_SIZE - eppnt->p_memsz < k) {
477 error = -ENOMEM;
478 goto out_close;
479 }
480
481 /*
482 * Find the end of the file mapping for this phdr, and
483 * keep track of the largest address we see for this.
484 */
485 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
486 if (k > elf_bss)
487 elf_bss = k;
488
489 /*
490 * Do the same thing for the memory mapping - between
491 * elf_bss and last_bss is the bss section.
492 */
493 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
494 if (k > last_bss)
495 last_bss = k;
496 }
497 }
498
499 /*
500 * Now fill out the bss section. First pad the last page up
501 * to the page boundary, and then perform a mmap to make sure
502 * that there are zero-mapped pages up to and including the
503 * last bss page.
504 */
505 if (padzero(elf_bss)) {
506 error = -EFAULT;
507 goto out_close;
508 }
509
510 /* What we have mapped so far */
511 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
512
513 /* Map the last of the bss segment */
514 if (last_bss > elf_bss) {
515 down_write(&current->mm->mmap_sem);
516 error = do_brk(elf_bss, last_bss - elf_bss);
517 up_write(&current->mm->mmap_sem);
518 if (BAD_ADDR(error))
519 goto out_close;
520 }
521
522 error = load_addr;
523
524 out_close:
525 kfree(elf_phdata);
526 out:
527 return error;
528 }
529
530 /*
531 * These are the functions used to load ELF style executables and shared
532 * libraries. There is no binary dependent code anywhere else.
533 */
534
535 #define INTERPRETER_NONE 0
536 #define INTERPRETER_ELF 2
537
538 #ifndef STACK_RND_MASK
539 #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
540 #endif
541
542 static unsigned long randomize_stack_top(unsigned long stack_top)
543 {
544 unsigned int random_variable = 0;
545
546 if ((current->flags & PF_RANDOMIZE) &&
547 !(current->personality & ADDR_NO_RANDOMIZE)) {
548 random_variable = get_random_int() & STACK_RND_MASK;
549 random_variable <<= PAGE_SHIFT;
550 }
551 #ifdef CONFIG_STACK_GROWSUP
552 return PAGE_ALIGN(stack_top) + random_variable;
553 #else
554 return PAGE_ALIGN(stack_top) - random_variable;
555 #endif
556 }
557
558 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
559 {
560 struct file *interpreter = NULL; /* to shut gcc up */
561 unsigned long load_addr = 0, load_bias = 0;
562 int load_addr_set = 0;
563 char * elf_interpreter = NULL;
564 unsigned long error;
565 struct elf_phdr *elf_ppnt, *elf_phdata;
566 unsigned long elf_bss, elf_brk;
567 int elf_exec_fileno;
568 int retval, i;
569 unsigned int size;
570 unsigned long elf_entry;
571 unsigned long interp_load_addr = 0;
572 unsigned long start_code, end_code, start_data, end_data;
573 unsigned long reloc_func_desc = 0;
574 int executable_stack = EXSTACK_DEFAULT;
575 unsigned long def_flags = 0;
576 struct {
577 struct elfhdr elf_ex;
578 struct elfhdr interp_elf_ex;
579 } *loc;
580
581 loc = kmalloc(sizeof(*loc), GFP_KERNEL);
582 if (!loc) {
583 retval = -ENOMEM;
584 goto out_ret;
585 }
586
587 /* Get the exec-header */
588 loc->elf_ex = *((struct elfhdr *)bprm->buf);
589
590 retval = -ENOEXEC;
591 /* First of all, some simple consistency checks */
592 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
593 goto out;
594
595 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
596 goto out;
597 if (!elf_check_arch(&loc->elf_ex))
598 goto out;
599 if (!bprm->file->f_op||!bprm->file->f_op->mmap)
600 goto out;
601
602 /* Now read in all of the header information */
603 if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr))
604 goto out;
605 if (loc->elf_ex.e_phnum < 1 ||
606 loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr))
607 goto out;
608 size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr);
609 retval = -ENOMEM;
610 elf_phdata = kmalloc(size, GFP_KERNEL);
611 if (!elf_phdata)
612 goto out;
613
614 retval = kernel_read(bprm->file, loc->elf_ex.e_phoff,
615 (char *)elf_phdata, size);
616 if (retval != size) {
617 if (retval >= 0)
618 retval = -EIO;
619 goto out_free_ph;
620 }
621
622 retval = get_unused_fd();
623 if (retval < 0)
624 goto out_free_ph;
625 get_file(bprm->file);
626 fd_install(elf_exec_fileno = retval, bprm->file);
627
628 elf_ppnt = elf_phdata;
629 elf_bss = 0;
630 elf_brk = 0;
631
632 start_code = ~0UL;
633 end_code = 0;
634 start_data = 0;
635 end_data = 0;
636
637 for (i = 0; i < loc->elf_ex.e_phnum; i++) {
638 if (elf_ppnt->p_type == PT_INTERP) {
639 /* This is the program interpreter used for
640 * shared libraries - for now assume that this
641 * is an a.out format binary
642 */
643 retval = -ENOEXEC;
644 if (elf_ppnt->p_filesz > PATH_MAX ||
645 elf_ppnt->p_filesz < 2)
646 goto out_free_file;
647
648 retval = -ENOMEM;
649 elf_interpreter = kmalloc(elf_ppnt->p_filesz,
650 GFP_KERNEL);
651 if (!elf_interpreter)
652 goto out_free_file;
653
654 retval = kernel_read(bprm->file, elf_ppnt->p_offset,
655 elf_interpreter,
656 elf_ppnt->p_filesz);
657 if (retval != elf_ppnt->p_filesz) {
658 if (retval >= 0)
659 retval = -EIO;
660 goto out_free_interp;
661 }
662 /* make sure path is NULL terminated */
663 retval = -ENOEXEC;
664 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
665 goto out_free_interp;
666
667 /*
668 * The early SET_PERSONALITY here is so that the lookup
669 * for the interpreter happens in the namespace of the
670 * to-be-execed image. SET_PERSONALITY can select an
671 * alternate root.
672 *
673 * However, SET_PERSONALITY is NOT allowed to switch
674 * this task into the new images's memory mapping
675 * policy - that is, TASK_SIZE must still evaluate to
676 * that which is appropriate to the execing application.
677 * This is because exit_mmap() needs to have TASK_SIZE
678 * evaluate to the size of the old image.
679 *
680 * So if (say) a 64-bit application is execing a 32-bit
681 * application it is the architecture's responsibility
682 * to defer changing the value of TASK_SIZE until the
683 * switch really is going to happen - do this in
684 * flush_thread(). - akpm
685 */
686 SET_PERSONALITY(loc->elf_ex, 0);
687
688 interpreter = open_exec(elf_interpreter);
689 retval = PTR_ERR(interpreter);
690 if (IS_ERR(interpreter))
691 goto out_free_interp;
692
693 /*
694 * If the binary is not readable then enforce
695 * mm->dumpable = 0 regardless of the interpreter's
696 * permissions.
697 */
698 if (file_permission(interpreter, MAY_READ) < 0)
699 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
700
701 retval = kernel_read(interpreter, 0, bprm->buf,
702 BINPRM_BUF_SIZE);
703 if (retval != BINPRM_BUF_SIZE) {
704 if (retval >= 0)
705 retval = -EIO;
706 goto out_free_dentry;
707 }
708
709 /* Get the exec headers */
710 loc->interp_elf_ex = *((struct elfhdr *)bprm->buf);
711 break;
712 }
713 elf_ppnt++;
714 }
715
716 elf_ppnt = elf_phdata;
717 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
718 if (elf_ppnt->p_type == PT_GNU_STACK) {
719 if (elf_ppnt->p_flags & PF_X)
720 executable_stack = EXSTACK_ENABLE_X;
721 else
722 executable_stack = EXSTACK_DISABLE_X;
723 break;
724 }
725
726 /* Some simple consistency checks for the interpreter */
727 if (elf_interpreter) {
728 retval = -ELIBBAD;
729 /* Not an ELF interpreter */
730 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
731 goto out_free_dentry;
732 /* Verify the interpreter has a valid arch */
733 if (!elf_check_arch(&loc->interp_elf_ex))
734 goto out_free_dentry;
735 } else {
736 /* Executables without an interpreter also need a personality */
737 SET_PERSONALITY(loc->elf_ex, 0);
738 }
739
740 /* Flush all traces of the currently running executable */
741 retval = flush_old_exec(bprm);
742 if (retval)
743 goto out_free_dentry;
744
745 /* OK, This is the point of no return */
746 current->flags &= ~PF_FORKNOEXEC;
747 current->mm->def_flags = def_flags;
748
749 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
750 may depend on the personality. */
751 SET_PERSONALITY(loc->elf_ex, 0);
752 if (elf_read_implies_exec(loc->elf_ex, executable_stack))
753 current->personality |= READ_IMPLIES_EXEC;
754
755 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
756 current->flags |= PF_RANDOMIZE;
757 arch_pick_mmap_layout(current->mm);
758
759 /* Do this so that we can load the interpreter, if need be. We will
760 change some of these later */
761 current->mm->free_area_cache = current->mm->mmap_base;
762 current->mm->cached_hole_size = 0;
763 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
764 executable_stack);
765 if (retval < 0) {
766 send_sig(SIGKILL, current, 0);
767 goto out_free_dentry;
768 }
769
770 current->mm->start_stack = bprm->p;
771
772 /* Now we do a little grungy work by mmaping the ELF image into
773 the correct location in memory. */
774 for(i = 0, elf_ppnt = elf_phdata;
775 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
776 int elf_prot = 0, elf_flags;
777 unsigned long k, vaddr;
778
779 if (elf_ppnt->p_type != PT_LOAD)
780 continue;
781
782 if (unlikely (elf_brk > elf_bss)) {
783 unsigned long nbyte;
784
785 /* There was a PT_LOAD segment with p_memsz > p_filesz
786 before this one. Map anonymous pages, if needed,
787 and clear the area. */
788 retval = set_brk (elf_bss + load_bias,
789 elf_brk + load_bias);
790 if (retval) {
791 send_sig(SIGKILL, current, 0);
792 goto out_free_dentry;
793 }
794 nbyte = ELF_PAGEOFFSET(elf_bss);
795 if (nbyte) {
796 nbyte = ELF_MIN_ALIGN - nbyte;
797 if (nbyte > elf_brk - elf_bss)
798 nbyte = elf_brk - elf_bss;
799 if (clear_user((void __user *)elf_bss +
800 load_bias, nbyte)) {
801 /*
802 * This bss-zeroing can fail if the ELF
803 * file specifies odd protections. So
804 * we don't check the return value
805 */
806 }
807 }
808 }
809
810 if (elf_ppnt->p_flags & PF_R)
811 elf_prot |= PROT_READ;
812 if (elf_ppnt->p_flags & PF_W)
813 elf_prot |= PROT_WRITE;
814 if (elf_ppnt->p_flags & PF_X)
815 elf_prot |= PROT_EXEC;
816
817 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
818
819 vaddr = elf_ppnt->p_vaddr;
820 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
821 elf_flags |= MAP_FIXED;
822 } else if (loc->elf_ex.e_type == ET_DYN) {
823 /* Try and get dynamic programs out of the way of the
824 * default mmap base, as well as whatever program they
825 * might try to exec. This is because the brk will
826 * follow the loader, and is not movable. */
827 #ifdef CONFIG_X86
828 load_bias = 0;
829 #else
830 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
831 #endif
832 }
833
834 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
835 elf_prot, elf_flags, 0);
836 if (BAD_ADDR(error)) {
837 send_sig(SIGKILL, current, 0);
838 retval = IS_ERR((void *)error) ?
839 PTR_ERR((void*)error) : -EINVAL;
840 goto out_free_dentry;
841 }
842
843 if (!load_addr_set) {
844 load_addr_set = 1;
845 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
846 if (loc->elf_ex.e_type == ET_DYN) {
847 load_bias += error -
848 ELF_PAGESTART(load_bias + vaddr);
849 load_addr += load_bias;
850 reloc_func_desc = load_bias;
851 }
852 }
853 k = elf_ppnt->p_vaddr;
854 if (k < start_code)
855 start_code = k;
856 if (start_data < k)
857 start_data = k;
858
859 /*
860 * Check to see if the section's size will overflow the
861 * allowed task size. Note that p_filesz must always be
862 * <= p_memsz so it is only necessary to check p_memsz.
863 */
864 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
865 elf_ppnt->p_memsz > TASK_SIZE ||
866 TASK_SIZE - elf_ppnt->p_memsz < k) {
867 /* set_brk can never work. Avoid overflows. */
868 send_sig(SIGKILL, current, 0);
869 retval = -EINVAL;
870 goto out_free_dentry;
871 }
872
873 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
874
875 if (k > elf_bss)
876 elf_bss = k;
877 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
878 end_code = k;
879 if (end_data < k)
880 end_data = k;
881 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
882 if (k > elf_brk)
883 elf_brk = k;
884 }
885
886 loc->elf_ex.e_entry += load_bias;
887 elf_bss += load_bias;
888 elf_brk += load_bias;
889 start_code += load_bias;
890 end_code += load_bias;
891 start_data += load_bias;
892 end_data += load_bias;
893
894 /* Calling set_brk effectively mmaps the pages that we need
895 * for the bss and break sections. We must do this before
896 * mapping in the interpreter, to make sure it doesn't wind
897 * up getting placed where the bss needs to go.
898 */
899 retval = set_brk(elf_bss, elf_brk);
900 if (retval) {
901 send_sig(SIGKILL, current, 0);
902 goto out_free_dentry;
903 }
904 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
905 send_sig(SIGSEGV, current, 0);
906 retval = -EFAULT; /* Nobody gets to see this, but.. */
907 goto out_free_dentry;
908 }
909
910 if (elf_interpreter) {
911 unsigned long uninitialized_var(interp_map_addr);
912
913 elf_entry = load_elf_interp(&loc->interp_elf_ex,
914 interpreter,
915 &interp_map_addr,
916 load_bias);
917 if (!IS_ERR((void *)elf_entry)) {
918 /*
919 * load_elf_interp() returns relocation
920 * adjustment
921 */
922 interp_load_addr = elf_entry;
923 elf_entry += loc->interp_elf_ex.e_entry;
924 }
925 if (BAD_ADDR(elf_entry)) {
926 force_sig(SIGSEGV, current);
927 retval = IS_ERR((void *)elf_entry) ?
928 (int)elf_entry : -EINVAL;
929 goto out_free_dentry;
930 }
931 reloc_func_desc = interp_load_addr;
932
933 allow_write_access(interpreter);
934 fput(interpreter);
935 kfree(elf_interpreter);
936 } else {
937 elf_entry = loc->elf_ex.e_entry;
938 if (BAD_ADDR(elf_entry)) {
939 force_sig(SIGSEGV, current);
940 retval = -EINVAL;
941 goto out_free_dentry;
942 }
943 }
944
945 kfree(elf_phdata);
946
947 sys_close(elf_exec_fileno);
948
949 set_binfmt(&elf_format);
950
951 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
952 retval = arch_setup_additional_pages(bprm, executable_stack);
953 if (retval < 0) {
954 send_sig(SIGKILL, current, 0);
955 goto out;
956 }
957 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
958
959 compute_creds(bprm);
960 current->flags &= ~PF_FORKNOEXEC;
961 retval = create_elf_tables(bprm, &loc->elf_ex,
962 load_addr, interp_load_addr);
963 if (retval < 0) {
964 send_sig(SIGKILL, current, 0);
965 goto out;
966 }
967 /* N.B. passed_fileno might not be initialized? */
968 current->mm->end_code = end_code;
969 current->mm->start_code = start_code;
970 current->mm->start_data = start_data;
971 current->mm->end_data = end_data;
972 current->mm->start_stack = bprm->p;
973
974 #ifdef arch_randomize_brk
975 if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1))
976 current->mm->brk = current->mm->start_brk =
977 arch_randomize_brk(current->mm);
978 #endif
979
980 if (current->personality & MMAP_PAGE_ZERO) {
981 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
982 and some applications "depend" upon this behavior.
983 Since we do not have the power to recompile these, we
984 emulate the SVr4 behavior. Sigh. */
985 down_write(&current->mm->mmap_sem);
986 error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
987 MAP_FIXED | MAP_PRIVATE, 0);
988 up_write(&current->mm->mmap_sem);
989 }
990
991 #ifdef ELF_PLAT_INIT
992 /*
993 * The ABI may specify that certain registers be set up in special
994 * ways (on i386 %edx is the address of a DT_FINI function, for
995 * example. In addition, it may also specify (eg, PowerPC64 ELF)
996 * that the e_entry field is the address of the function descriptor
997 * for the startup routine, rather than the address of the startup
998 * routine itself. This macro performs whatever initialization to
999 * the regs structure is required as well as any relocations to the
1000 * function descriptor entries when executing dynamically links apps.
1001 */
1002 ELF_PLAT_INIT(regs, reloc_func_desc);
1003 #endif
1004
1005 start_thread(regs, elf_entry, bprm->p);
1006 if (unlikely(current->ptrace & PT_PTRACED)) {
1007 if (current->ptrace & PT_TRACE_EXEC)
1008 ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP);
1009 else
1010 send_sig(SIGTRAP, current, 0);
1011 }
1012 retval = 0;
1013 out:
1014 kfree(loc);
1015 out_ret:
1016 return retval;
1017
1018 /* error cleanup */
1019 out_free_dentry:
1020 allow_write_access(interpreter);
1021 if (interpreter)
1022 fput(interpreter);
1023 out_free_interp:
1024 kfree(elf_interpreter);
1025 out_free_file:
1026 sys_close(elf_exec_fileno);
1027 out_free_ph:
1028 kfree(elf_phdata);
1029 goto out;
1030 }
1031
1032 /* This is really simpleminded and specialized - we are loading an
1033 a.out library that is given an ELF header. */
1034 static int load_elf_library(struct file *file)
1035 {
1036 struct elf_phdr *elf_phdata;
1037 struct elf_phdr *eppnt;
1038 unsigned long elf_bss, bss, len;
1039 int retval, error, i, j;
1040 struct elfhdr elf_ex;
1041
1042 error = -ENOEXEC;
1043 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
1044 if (retval != sizeof(elf_ex))
1045 goto out;
1046
1047 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
1048 goto out;
1049
1050 /* First of all, some simple consistency checks */
1051 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
1052 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
1053 goto out;
1054
1055 /* Now read in all of the header information */
1056
1057 j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
1058 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1059
1060 error = -ENOMEM;
1061 elf_phdata = kmalloc(j, GFP_KERNEL);
1062 if (!elf_phdata)
1063 goto out;
1064
1065 eppnt = elf_phdata;
1066 error = -ENOEXEC;
1067 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
1068 if (retval != j)
1069 goto out_free_ph;
1070
1071 for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
1072 if ((eppnt + i)->p_type == PT_LOAD)
1073 j++;
1074 if (j != 1)
1075 goto out_free_ph;
1076
1077 while (eppnt->p_type != PT_LOAD)
1078 eppnt++;
1079
1080 /* Now use mmap to map the library into memory. */
1081 down_write(&current->mm->mmap_sem);
1082 error = do_mmap(file,
1083 ELF_PAGESTART(eppnt->p_vaddr),
1084 (eppnt->p_filesz +
1085 ELF_PAGEOFFSET(eppnt->p_vaddr)),
1086 PROT_READ | PROT_WRITE | PROT_EXEC,
1087 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
1088 (eppnt->p_offset -
1089 ELF_PAGEOFFSET(eppnt->p_vaddr)));
1090 up_write(&current->mm->mmap_sem);
1091 if (error != ELF_PAGESTART(eppnt->p_vaddr))
1092 goto out_free_ph;
1093
1094 elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
1095 if (padzero(elf_bss)) {
1096 error = -EFAULT;
1097 goto out_free_ph;
1098 }
1099
1100 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
1101 ELF_MIN_ALIGN - 1);
1102 bss = eppnt->p_memsz + eppnt->p_vaddr;
1103 if (bss > len) {
1104 down_write(&current->mm->mmap_sem);
1105 do_brk(len, bss - len);
1106 up_write(&current->mm->mmap_sem);
1107 }
1108 error = 0;
1109
1110 out_free_ph:
1111 kfree(elf_phdata);
1112 out:
1113 return error;
1114 }
1115
1116 /*
1117 * Note that some platforms still use traditional core dumps and not
1118 * the ELF core dump. Each platform can select it as appropriate.
1119 */
1120 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
1121
1122 /*
1123 * ELF core dumper
1124 *
1125 * Modelled on fs/exec.c:aout_core_dump()
1126 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1127 */
1128 /*
1129 * These are the only things you should do on a core-file: use only these
1130 * functions to write out all the necessary info.
1131 */
1132 static int dump_write(struct file *file, const void *addr, int nr)
1133 {
1134 return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
1135 }
1136
1137 static int dump_seek(struct file *file, loff_t off)
1138 {
1139 if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
1140 if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
1141 return 0;
1142 } else {
1143 char *buf = (char *)get_zeroed_page(GFP_KERNEL);
1144 if (!buf)
1145 return 0;
1146 while (off > 0) {
1147 unsigned long n = off;
1148 if (n > PAGE_SIZE)
1149 n = PAGE_SIZE;
1150 if (!dump_write(file, buf, n))
1151 return 0;
1152 off -= n;
1153 }
1154 free_page((unsigned long)buf);
1155 }
1156 return 1;
1157 }
1158
1159 /*
1160 * Decide what to dump of a segment, part, all or none.
1161 */
1162 static unsigned long vma_dump_size(struct vm_area_struct *vma,
1163 unsigned long mm_flags)
1164 {
1165 /* The vma can be set up to tell us the answer directly. */
1166 if (vma->vm_flags & VM_ALWAYSDUMP)
1167 goto whole;
1168
1169 /* Do not dump I/O mapped devices or special mappings */
1170 if (vma->vm_flags & (VM_IO | VM_RESERVED))
1171 return 0;
1172
1173 #define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1174
1175 /* By default, dump shared memory if mapped from an anonymous file. */
1176 if (vma->vm_flags & VM_SHARED) {
1177 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ?
1178 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
1179 goto whole;
1180 return 0;
1181 }
1182
1183 /* Dump segments that have been written to. */
1184 if (vma->anon_vma && FILTER(ANON_PRIVATE))
1185 goto whole;
1186 if (vma->vm_file == NULL)
1187 return 0;
1188
1189 if (FILTER(MAPPED_PRIVATE))
1190 goto whole;
1191
1192 /*
1193 * If this looks like the beginning of a DSO or executable mapping,
1194 * check for an ELF header. If we find one, dump the first page to
1195 * aid in determining what was mapped here.
1196 */
1197 if (FILTER(ELF_HEADERS) && vma->vm_file != NULL && vma->vm_pgoff == 0) {
1198 u32 __user *header = (u32 __user *) vma->vm_start;
1199 u32 word;
1200 /*
1201 * Doing it this way gets the constant folded by GCC.
1202 */
1203 union {
1204 u32 cmp;
1205 char elfmag[SELFMAG];
1206 } magic;
1207 BUILD_BUG_ON(SELFMAG != sizeof word);
1208 magic.elfmag[EI_MAG0] = ELFMAG0;
1209 magic.elfmag[EI_MAG1] = ELFMAG1;
1210 magic.elfmag[EI_MAG2] = ELFMAG2;
1211 magic.elfmag[EI_MAG3] = ELFMAG3;
1212 if (get_user(word, header) == 0 && word == magic.cmp)
1213 return PAGE_SIZE;
1214 }
1215
1216 #undef FILTER
1217
1218 return 0;
1219
1220 whole:
1221 return vma->vm_end - vma->vm_start;
1222 }
1223
1224 /* An ELF note in memory */
1225 struct memelfnote
1226 {
1227 const char *name;
1228 int type;
1229 unsigned int datasz;
1230 void *data;
1231 };
1232
1233 static int notesize(struct memelfnote *en)
1234 {
1235 int sz;
1236
1237 sz = sizeof(struct elf_note);
1238 sz += roundup(strlen(en->name) + 1, 4);
1239 sz += roundup(en->datasz, 4);
1240
1241 return sz;
1242 }
1243
1244 #define DUMP_WRITE(addr, nr, foffset) \
1245 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
1246
1247 static int alignfile(struct file *file, loff_t *foffset)
1248 {
1249 static const char buf[4] = { 0, };
1250 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
1251 return 1;
1252 }
1253
1254 static int writenote(struct memelfnote *men, struct file *file,
1255 loff_t *foffset)
1256 {
1257 struct elf_note en;
1258 en.n_namesz = strlen(men->name) + 1;
1259 en.n_descsz = men->datasz;
1260 en.n_type = men->type;
1261
1262 DUMP_WRITE(&en, sizeof(en), foffset);
1263 DUMP_WRITE(men->name, en.n_namesz, foffset);
1264 if (!alignfile(file, foffset))
1265 return 0;
1266 DUMP_WRITE(men->data, men->datasz, foffset);
1267 if (!alignfile(file, foffset))
1268 return 0;
1269
1270 return 1;
1271 }
1272 #undef DUMP_WRITE
1273
1274 #define DUMP_WRITE(addr, nr) \
1275 if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
1276 goto end_coredump;
1277 #define DUMP_SEEK(off) \
1278 if (!dump_seek(file, (off))) \
1279 goto end_coredump;
1280
1281 static void fill_elf_header(struct elfhdr *elf, int segs,
1282 u16 machine, u32 flags, u8 osabi)
1283 {
1284 memset(elf, 0, sizeof(*elf));
1285
1286 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1287 elf->e_ident[EI_CLASS] = ELF_CLASS;
1288 elf->e_ident[EI_DATA] = ELF_DATA;
1289 elf->e_ident[EI_VERSION] = EV_CURRENT;
1290 elf->e_ident[EI_OSABI] = ELF_OSABI;
1291
1292 elf->e_type = ET_CORE;
1293 elf->e_machine = machine;
1294 elf->e_version = EV_CURRENT;
1295 elf->e_phoff = sizeof(struct elfhdr);
1296 elf->e_flags = flags;
1297 elf->e_ehsize = sizeof(struct elfhdr);
1298 elf->e_phentsize = sizeof(struct elf_phdr);
1299 elf->e_phnum = segs;
1300
1301 return;
1302 }
1303
1304 static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
1305 {
1306 phdr->p_type = PT_NOTE;
1307 phdr->p_offset = offset;
1308 phdr->p_vaddr = 0;
1309 phdr->p_paddr = 0;
1310 phdr->p_filesz = sz;
1311 phdr->p_memsz = 0;
1312 phdr->p_flags = 0;
1313 phdr->p_align = 0;
1314 return;
1315 }
1316
1317 static void fill_note(struct memelfnote *note, const char *name, int type,
1318 unsigned int sz, void *data)
1319 {
1320 note->name = name;
1321 note->type = type;
1322 note->datasz = sz;
1323 note->data = data;
1324 return;
1325 }
1326
1327 /*
1328 * fill up all the fields in prstatus from the given task struct, except
1329 * registers which need to be filled up separately.
1330 */
1331 static void fill_prstatus(struct elf_prstatus *prstatus,
1332 struct task_struct *p, long signr)
1333 {
1334 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1335 prstatus->pr_sigpend = p->pending.signal.sig[0];
1336 prstatus->pr_sighold = p->blocked.sig[0];
1337 prstatus->pr_pid = task_pid_vnr(p);
1338 prstatus->pr_ppid = task_pid_vnr(p->real_parent);
1339 prstatus->pr_pgrp = task_pgrp_vnr(p);
1340 prstatus->pr_sid = task_session_vnr(p);
1341 if (thread_group_leader(p)) {
1342 /*
1343 * This is the record for the group leader. Add in the
1344 * cumulative times of previous dead threads. This total
1345 * won't include the time of each live thread whose state
1346 * is included in the core dump. The final total reported
1347 * to our parent process when it calls wait4 will include
1348 * those sums as well as the little bit more time it takes
1349 * this and each other thread to finish dying after the
1350 * core dump synchronization phase.
1351 */
1352 cputime_to_timeval(cputime_add(p->utime, p->signal->utime),
1353 &prstatus->pr_utime);
1354 cputime_to_timeval(cputime_add(p->stime, p->signal->stime),
1355 &prstatus->pr_stime);
1356 } else {
1357 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1358 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1359 }
1360 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1361 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1362 }
1363
1364 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1365 struct mm_struct *mm)
1366 {
1367 unsigned int i, len;
1368
1369 /* first copy the parameters from user space */
1370 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1371
1372 len = mm->arg_end - mm->arg_start;
1373 if (len >= ELF_PRARGSZ)
1374 len = ELF_PRARGSZ-1;
1375 if (copy_from_user(&psinfo->pr_psargs,
1376 (const char __user *)mm->arg_start, len))
1377 return -EFAULT;
1378 for(i = 0; i < len; i++)
1379 if (psinfo->pr_psargs[i] == 0)
1380 psinfo->pr_psargs[i] = ' ';
1381 psinfo->pr_psargs[len] = 0;
1382
1383 psinfo->pr_pid = task_pid_vnr(p);
1384 psinfo->pr_ppid = task_pid_vnr(p->real_parent);
1385 psinfo->pr_pgrp = task_pgrp_vnr(p);
1386 psinfo->pr_sid = task_session_vnr(p);
1387
1388 i = p->state ? ffz(~p->state) + 1 : 0;
1389 psinfo->pr_state = i;
1390 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
1391 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1392 psinfo->pr_nice = task_nice(p);
1393 psinfo->pr_flag = p->flags;
1394 SET_UID(psinfo->pr_uid, p->uid);
1395 SET_GID(psinfo->pr_gid, p->gid);
1396 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1397
1398 return 0;
1399 }
1400
1401 static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
1402 {
1403 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
1404 int i = 0;
1405 do
1406 i += 2;
1407 while (auxv[i - 2] != AT_NULL);
1408 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
1409 }
1410
1411 #ifdef CORE_DUMP_USE_REGSET
1412 #include <linux/regset.h>
1413
1414 struct elf_thread_core_info {
1415 struct elf_thread_core_info *next;
1416 struct task_struct *task;
1417 struct elf_prstatus prstatus;
1418 struct memelfnote notes[0];
1419 };
1420
1421 struct elf_note_info {
1422 struct elf_thread_core_info *thread;
1423 struct memelfnote psinfo;
1424 struct memelfnote auxv;
1425 size_t size;
1426 int thread_notes;
1427 };
1428
1429 /*
1430 * When a regset has a writeback hook, we call it on each thread before
1431 * dumping user memory. On register window machines, this makes sure the
1432 * user memory backing the register data is up to date before we read it.
1433 */
1434 static void do_thread_regset_writeback(struct task_struct *task,
1435 const struct user_regset *regset)
1436 {
1437 if (regset->writeback)
1438 regset->writeback(task, regset, 1);
1439 }
1440
1441 static int fill_thread_core_info(struct elf_thread_core_info *t,
1442 const struct user_regset_view *view,
1443 long signr, size_t *total)
1444 {
1445 unsigned int i;
1446
1447 /*
1448 * NT_PRSTATUS is the one special case, because the regset data
1449 * goes into the pr_reg field inside the note contents, rather
1450 * than being the whole note contents. We fill the reset in here.
1451 * We assume that regset 0 is NT_PRSTATUS.
1452 */
1453 fill_prstatus(&t->prstatus, t->task, signr);
1454 (void) view->regsets[0].get(t->task, &view->regsets[0],
1455 0, sizeof(t->prstatus.pr_reg),
1456 &t->prstatus.pr_reg, NULL);
1457
1458 fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
1459 sizeof(t->prstatus), &t->prstatus);
1460 *total += notesize(&t->notes[0]);
1461
1462 do_thread_regset_writeback(t->task, &view->regsets[0]);
1463
1464 /*
1465 * Each other regset might generate a note too. For each regset
1466 * that has no core_note_type or is inactive, we leave t->notes[i]
1467 * all zero and we'll know to skip writing it later.
1468 */
1469 for (i = 1; i < view->n; ++i) {
1470 const struct user_regset *regset = &view->regsets[i];
1471 do_thread_regset_writeback(t->task, regset);
1472 if (regset->core_note_type &&
1473 (!regset->active || regset->active(t->task, regset))) {
1474 int ret;
1475 size_t size = regset->n * regset->size;
1476 void *data = kmalloc(size, GFP_KERNEL);
1477 if (unlikely(!data))
1478 return 0;
1479 ret = regset->get(t->task, regset,
1480 0, size, data, NULL);
1481 if (unlikely(ret))
1482 kfree(data);
1483 else {
1484 if (regset->core_note_type != NT_PRFPREG)
1485 fill_note(&t->notes[i], "LINUX",
1486 regset->core_note_type,
1487 size, data);
1488 else {
1489 t->prstatus.pr_fpvalid = 1;
1490 fill_note(&t->notes[i], "CORE",
1491 NT_PRFPREG, size, data);
1492 }
1493 *total += notesize(&t->notes[i]);
1494 }
1495 }
1496 }
1497
1498 return 1;
1499 }
1500
1501 static int fill_note_info(struct elfhdr *elf, int phdrs,
1502 struct elf_note_info *info,
1503 long signr, struct pt_regs *regs)
1504 {
1505 struct task_struct *dump_task = current;
1506 const struct user_regset_view *view = task_user_regset_view(dump_task);
1507 struct elf_thread_core_info *t;
1508 struct elf_prpsinfo *psinfo;
1509 struct core_thread *ct;
1510 unsigned int i;
1511
1512 info->size = 0;
1513 info->thread = NULL;
1514
1515 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1516 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1517
1518 if (psinfo == NULL)
1519 return 0;
1520
1521 /*
1522 * Figure out how many notes we're going to need for each thread.
1523 */
1524 info->thread_notes = 0;
1525 for (i = 0; i < view->n; ++i)
1526 if (view->regsets[i].core_note_type != 0)
1527 ++info->thread_notes;
1528
1529 /*
1530 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1531 * since it is our one special case.
1532 */
1533 if (unlikely(info->thread_notes == 0) ||
1534 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
1535 WARN_ON(1);
1536 return 0;
1537 }
1538
1539 /*
1540 * Initialize the ELF file header.
1541 */
1542 fill_elf_header(elf, phdrs,
1543 view->e_machine, view->e_flags, view->ei_osabi);
1544
1545 /*
1546 * Allocate a structure for each thread.
1547 */
1548 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) {
1549 t = kzalloc(offsetof(struct elf_thread_core_info,
1550 notes[info->thread_notes]),
1551 GFP_KERNEL);
1552 if (unlikely(!t))
1553 return 0;
1554
1555 t->task = ct->task;
1556 if (ct->task == dump_task || !info->thread) {
1557 t->next = info->thread;
1558 info->thread = t;
1559 } else {
1560 /*
1561 * Make sure to keep the original task at
1562 * the head of the list.
1563 */
1564 t->next = info->thread->next;
1565 info->thread->next = t;
1566 }
1567 }
1568
1569 /*
1570 * Now fill in each thread's information.
1571 */
1572 for (t = info->thread; t != NULL; t = t->next)
1573 if (!fill_thread_core_info(t, view, signr, &info->size))
1574 return 0;
1575
1576 /*
1577 * Fill in the two process-wide notes.
1578 */
1579 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
1580 info->size += notesize(&info->psinfo);
1581
1582 fill_auxv_note(&info->auxv, current->mm);
1583 info->size += notesize(&info->auxv);
1584
1585 return 1;
1586 }
1587
1588 static size_t get_note_info_size(struct elf_note_info *info)
1589 {
1590 return info->size;
1591 }
1592
1593 /*
1594 * Write all the notes for each thread. When writing the first thread, the
1595 * process-wide notes are interleaved after the first thread-specific note.
1596 */
1597 static int write_note_info(struct elf_note_info *info,
1598 struct file *file, loff_t *foffset)
1599 {
1600 bool first = 1;
1601 struct elf_thread_core_info *t = info->thread;
1602
1603 do {
1604 int i;
1605
1606 if (!writenote(&t->notes[0], file, foffset))
1607 return 0;
1608
1609 if (first && !writenote(&info->psinfo, file, foffset))
1610 return 0;
1611 if (first && !writenote(&info->auxv, file, foffset))
1612 return 0;
1613
1614 for (i = 1; i < info->thread_notes; ++i)
1615 if (t->notes[i].data &&
1616 !writenote(&t->notes[i], file, foffset))
1617 return 0;
1618
1619 first = 0;
1620 t = t->next;
1621 } while (t);
1622
1623 return 1;
1624 }
1625
1626 static void free_note_info(struct elf_note_info *info)
1627 {
1628 struct elf_thread_core_info *threads = info->thread;
1629 while (threads) {
1630 unsigned int i;
1631 struct elf_thread_core_info *t = threads;
1632 threads = t->next;
1633 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
1634 for (i = 1; i < info->thread_notes; ++i)
1635 kfree(t->notes[i].data);
1636 kfree(t);
1637 }
1638 kfree(info->psinfo.data);
1639 }
1640
1641 #else
1642
1643 /* Here is the structure in which status of each thread is captured. */
1644 struct elf_thread_status
1645 {
1646 struct list_head list;
1647 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1648 elf_fpregset_t fpu; /* NT_PRFPREG */
1649 struct task_struct *thread;
1650 #ifdef ELF_CORE_COPY_XFPREGS
1651 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
1652 #endif
1653 struct memelfnote notes[3];
1654 int num_notes;
1655 };
1656
1657 /*
1658 * In order to add the specific thread information for the elf file format,
1659 * we need to keep a linked list of every threads pr_status and then create
1660 * a single section for them in the final core file.
1661 */
1662 static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1663 {
1664 int sz = 0;
1665 struct task_struct *p = t->thread;
1666 t->num_notes = 0;
1667
1668 fill_prstatus(&t->prstatus, p, signr);
1669 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1670
1671 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1672 &(t->prstatus));
1673 t->num_notes++;
1674 sz += notesize(&t->notes[0]);
1675
1676 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1677 &t->fpu))) {
1678 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1679 &(t->fpu));
1680 t->num_notes++;
1681 sz += notesize(&t->notes[1]);
1682 }
1683
1684 #ifdef ELF_CORE_COPY_XFPREGS
1685 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
1686 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1687 sizeof(t->xfpu), &t->xfpu);
1688 t->num_notes++;
1689 sz += notesize(&t->notes[2]);
1690 }
1691 #endif
1692 return sz;
1693 }
1694
1695 struct elf_note_info {
1696 struct memelfnote *notes;
1697 struct elf_prstatus *prstatus; /* NT_PRSTATUS */
1698 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */
1699 struct list_head thread_list;
1700 elf_fpregset_t *fpu;
1701 #ifdef ELF_CORE_COPY_XFPREGS
1702 elf_fpxregset_t *xfpu;
1703 #endif
1704 int thread_status_size;
1705 int numnote;
1706 };
1707
1708 static int fill_note_info(struct elfhdr *elf, int phdrs,
1709 struct elf_note_info *info,
1710 long signr, struct pt_regs *regs)
1711 {
1712 #define NUM_NOTES 6
1713 struct list_head *t;
1714
1715 info->notes = NULL;
1716 info->prstatus = NULL;
1717 info->psinfo = NULL;
1718 info->fpu = NULL;
1719 #ifdef ELF_CORE_COPY_XFPREGS
1720 info->xfpu = NULL;
1721 #endif
1722 INIT_LIST_HEAD(&info->thread_list);
1723
1724 info->notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote),
1725 GFP_KERNEL);
1726 if (!info->notes)
1727 return 0;
1728 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
1729 if (!info->psinfo)
1730 return 0;
1731 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
1732 if (!info->prstatus)
1733 return 0;
1734 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
1735 if (!info->fpu)
1736 return 0;
1737 #ifdef ELF_CORE_COPY_XFPREGS
1738 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
1739 if (!info->xfpu)
1740 return 0;
1741 #endif
1742
1743 info->thread_status_size = 0;
1744 if (signr) {
1745 struct core_thread *ct;
1746 struct elf_thread_status *ets;
1747
1748 for (ct = current->mm->core_state->dumper.next;
1749 ct; ct = ct->next) {
1750 ets = kzalloc(sizeof(*ets), GFP_KERNEL);
1751 if (!ets)
1752 return 0;
1753
1754 ets->thread = ct->task;
1755 list_add(&ets->list, &info->thread_list);
1756 }
1757
1758 list_for_each(t, &info->thread_list) {
1759 int sz;
1760
1761 ets = list_entry(t, struct elf_thread_status, list);
1762 sz = elf_dump_thread_status(signr, ets);
1763 info->thread_status_size += sz;
1764 }
1765 }
1766 /* now collect the dump for the current */
1767 memset(info->prstatus, 0, sizeof(*info->prstatus));
1768 fill_prstatus(info->prstatus, current, signr);
1769 elf_core_copy_regs(&info->prstatus->pr_reg, regs);
1770
1771 /* Set up header */
1772 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI);
1773
1774 /*
1775 * Set up the notes in similar form to SVR4 core dumps made
1776 * with info from their /proc.
1777 */
1778
1779 fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
1780 sizeof(*info->prstatus), info->prstatus);
1781 fill_psinfo(info->psinfo, current->group_leader, current->mm);
1782 fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
1783 sizeof(*info->psinfo), info->psinfo);
1784
1785 info->numnote = 2;
1786
1787 fill_auxv_note(&info->notes[info->numnote++], current->mm);
1788
1789 /* Try to dump the FPU. */
1790 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
1791 info->fpu);
1792 if (info->prstatus->pr_fpvalid)
1793 fill_note(info->notes + info->numnote++,
1794 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
1795 #ifdef ELF_CORE_COPY_XFPREGS
1796 if (elf_core_copy_task_xfpregs(current, info->xfpu))
1797 fill_note(info->notes + info->numnote++,
1798 "LINUX", ELF_CORE_XFPREG_TYPE,
1799 sizeof(*info->xfpu), info->xfpu);
1800 #endif
1801
1802 return 1;
1803
1804 #undef NUM_NOTES
1805 }
1806
1807 static size_t get_note_info_size(struct elf_note_info *info)
1808 {
1809 int sz = 0;
1810 int i;
1811
1812 for (i = 0; i < info->numnote; i++)
1813 sz += notesize(info->notes + i);
1814
1815 sz += info->thread_status_size;
1816
1817 return sz;
1818 }
1819
1820 static int write_note_info(struct elf_note_info *info,
1821 struct file *file, loff_t *foffset)
1822 {
1823 int i;
1824 struct list_head *t;
1825
1826 for (i = 0; i < info->numnote; i++)
1827 if (!writenote(info->notes + i, file, foffset))
1828 return 0;
1829
1830 /* write out the thread status notes section */
1831 list_for_each(t, &info->thread_list) {
1832 struct elf_thread_status *tmp =
1833 list_entry(t, struct elf_thread_status, list);
1834
1835 for (i = 0; i < tmp->num_notes; i++)
1836 if (!writenote(&tmp->notes[i], file, foffset))
1837 return 0;
1838 }
1839
1840 return 1;
1841 }
1842
1843 static void free_note_info(struct elf_note_info *info)
1844 {
1845 while (!list_empty(&info->thread_list)) {
1846 struct list_head *tmp = info->thread_list.next;
1847 list_del(tmp);
1848 kfree(list_entry(tmp, struct elf_thread_status, list));
1849 }
1850
1851 kfree(info->prstatus);
1852 kfree(info->psinfo);
1853 kfree(info->notes);
1854 kfree(info->fpu);
1855 #ifdef ELF_CORE_COPY_XFPREGS
1856 kfree(info->xfpu);
1857 #endif
1858 }
1859
1860 #endif
1861
1862 static struct vm_area_struct *first_vma(struct task_struct *tsk,
1863 struct vm_area_struct *gate_vma)
1864 {
1865 struct vm_area_struct *ret = tsk->mm->mmap;
1866
1867 if (ret)
1868 return ret;
1869 return gate_vma;
1870 }
1871 /*
1872 * Helper function for iterating across a vma list. It ensures that the caller
1873 * will visit `gate_vma' prior to terminating the search.
1874 */
1875 static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma,
1876 struct vm_area_struct *gate_vma)
1877 {
1878 struct vm_area_struct *ret;
1879
1880 ret = this_vma->vm_next;
1881 if (ret)
1882 return ret;
1883 if (this_vma == gate_vma)
1884 return NULL;
1885 return gate_vma;
1886 }
1887
1888 /*
1889 * Actual dumper
1890 *
1891 * This is a two-pass process; first we find the offsets of the bits,
1892 * and then they are actually written out. If we run out of core limit
1893 * we just truncate.
1894 */
1895 static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
1896 {
1897 int has_dumped = 0;
1898 mm_segment_t fs;
1899 int segs;
1900 size_t size = 0;
1901 struct vm_area_struct *vma, *gate_vma;
1902 struct elfhdr *elf = NULL;
1903 loff_t offset = 0, dataoff, foffset;
1904 unsigned long mm_flags;
1905 struct elf_note_info info;
1906
1907 /*
1908 * We no longer stop all VM operations.
1909 *
1910 * This is because those proceses that could possibly change map_count
1911 * or the mmap / vma pages are now blocked in do_exit on current
1912 * finishing this core dump.
1913 *
1914 * Only ptrace can touch these memory addresses, but it doesn't change
1915 * the map_count or the pages allocated. So no possibility of crashing
1916 * exists while dumping the mm->vm_next areas to the core file.
1917 */
1918
1919 /* alloc memory for large data structures: too large to be on stack */
1920 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1921 if (!elf)
1922 goto out;
1923
1924 segs = current->mm->map_count;
1925 #ifdef ELF_CORE_EXTRA_PHDRS
1926 segs += ELF_CORE_EXTRA_PHDRS;
1927 #endif
1928
1929 gate_vma = get_gate_vma(current);
1930 if (gate_vma != NULL)
1931 segs++;
1932
1933 /*
1934 * Collect all the non-memory information about the process for the
1935 * notes. This also sets up the file header.
1936 */
1937 if (!fill_note_info(elf, segs + 1, /* including notes section */
1938 &info, signr, regs))
1939 goto cleanup;
1940
1941 has_dumped = 1;
1942 current->flags |= PF_DUMPCORE;
1943
1944 fs = get_fs();
1945 set_fs(KERNEL_DS);
1946
1947 DUMP_WRITE(elf, sizeof(*elf));
1948 offset += sizeof(*elf); /* Elf header */
1949 offset += (segs + 1) * sizeof(struct elf_phdr); /* Program headers */
1950 foffset = offset;
1951
1952 /* Write notes phdr entry */
1953 {
1954 struct elf_phdr phdr;
1955 size_t sz = get_note_info_size(&info);
1956
1957 sz += elf_coredump_extra_notes_size();
1958
1959 fill_elf_note_phdr(&phdr, sz, offset);
1960 offset += sz;
1961 DUMP_WRITE(&phdr, sizeof(phdr));
1962 }
1963
1964 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1965
1966 /*
1967 * We must use the same mm->flags while dumping core to avoid
1968 * inconsistency between the program headers and bodies, otherwise an
1969 * unusable core file can be generated.
1970 */
1971 mm_flags = current->mm->flags;
1972
1973 /* Write program headers for segments dump */
1974 for (vma = first_vma(current, gate_vma); vma != NULL;
1975 vma = next_vma(vma, gate_vma)) {
1976 struct elf_phdr phdr;
1977
1978 phdr.p_type = PT_LOAD;
1979 phdr.p_offset = offset;
1980 phdr.p_vaddr = vma->vm_start;
1981 phdr.p_paddr = 0;
1982 phdr.p_filesz = vma_dump_size(vma, mm_flags);
1983 phdr.p_memsz = vma->vm_end - vma->vm_start;
1984 offset += phdr.p_filesz;
1985 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
1986 if (vma->vm_flags & VM_WRITE)
1987 phdr.p_flags |= PF_W;
1988 if (vma->vm_flags & VM_EXEC)
1989 phdr.p_flags |= PF_X;
1990 phdr.p_align = ELF_EXEC_PAGESIZE;
1991
1992 DUMP_WRITE(&phdr, sizeof(phdr));
1993 }
1994
1995 #ifdef ELF_CORE_WRITE_EXTRA_PHDRS
1996 ELF_CORE_WRITE_EXTRA_PHDRS;
1997 #endif
1998
1999 /* write out the notes section */
2000 if (!write_note_info(&info, file, &foffset))
2001 goto end_coredump;
2002
2003 if (elf_coredump_extra_notes_write(file, &foffset))
2004 goto end_coredump;
2005
2006 /* Align to page */
2007 DUMP_SEEK(dataoff - foffset);
2008
2009 for (vma = first_vma(current, gate_vma); vma != NULL;
2010 vma = next_vma(vma, gate_vma)) {
2011 unsigned long addr;
2012 unsigned long end;
2013
2014 end = vma->vm_start + vma_dump_size(vma, mm_flags);
2015
2016 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
2017 struct page *page;
2018 struct vm_area_struct *tmp_vma;
2019
2020 if (get_user_pages(current, current->mm, addr, 1, 0, 1,
2021 &page, &tmp_vma) <= 0) {
2022 DUMP_SEEK(PAGE_SIZE);
2023 } else {
2024 if (page == ZERO_PAGE(0)) {
2025 if (!dump_seek(file, PAGE_SIZE)) {
2026 page_cache_release(page);
2027 goto end_coredump;
2028 }
2029 } else {
2030 void *kaddr;
2031 flush_cache_page(tmp_vma, addr,
2032 page_to_pfn(page));
2033 kaddr = kmap(page);
2034 if ((size += PAGE_SIZE) > limit ||
2035 !dump_write(file, kaddr,
2036 PAGE_SIZE)) {
2037 kunmap(page);
2038 page_cache_release(page);
2039 goto end_coredump;
2040 }
2041 kunmap(page);
2042 }
2043 page_cache_release(page);
2044 }
2045 }
2046 }
2047
2048 #ifdef ELF_CORE_WRITE_EXTRA_DATA
2049 ELF_CORE_WRITE_EXTRA_DATA;
2050 #endif
2051
2052 end_coredump:
2053 set_fs(fs);
2054
2055 cleanup:
2056 free_note_info(&info);
2057 kfree(elf);
2058 out:
2059 return has_dumped;
2060 }
2061
2062 #endif /* USE_ELF_CORE_DUMP */
2063
2064 static int __init init_elf_binfmt(void)
2065 {
2066 return register_binfmt(&elf_format);
2067 }
2068
2069 static void __exit exit_elf_binfmt(void)
2070 {
2071 /* Remove the COFF and ELF loaders. */
2072 unregister_binfmt(&elf_format);
2073 }
2074
2075 core_initcall(init_elf_binfmt);
2076 module_exit(exit_elf_binfmt);
2077 MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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