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nfs41: implement DESTROY_CLIENTID operation
[linux-btrfs-devel.git] / fs / binfmt_elf.c
blobdd0fdfc56d38c4753091ff44da049158048a8b6d
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 <linux/coredump.h>
35 #include <asm/uaccess.h>
36 #include <asm/param.h>
37 #include <asm/page.h>
38
39 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs);
40 static int load_elf_library(struct file *);
41 static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *,
42 int, int, unsigned long);
43
44 /*
45 * If we don't support core dumping, then supply a NULL so we
46 * don't even try.
47 */
48 #ifdef CONFIG_ELF_CORE
49 static int elf_core_dump(struct coredump_params *cprm);
50 #else
51 #define elf_core_dump NULL
52 #endif
53
54 #if ELF_EXEC_PAGESIZE > PAGE_SIZE
55 #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
56 #else
57 #define ELF_MIN_ALIGN PAGE_SIZE
58 #endif
59
60 #ifndef ELF_CORE_EFLAGS
61 #define ELF_CORE_EFLAGS 0
62 #endif
63
64 #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
65 #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
66 #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
67
68 static struct linux_binfmt elf_format = {
69 .module = THIS_MODULE,
70 .load_binary = load_elf_binary,
71 .load_shlib = load_elf_library,
72 .core_dump = elf_core_dump,
73 .min_coredump = ELF_EXEC_PAGESIZE,
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 static unsigned long elf_map(struct file *filep, unsigned long addr,
319 struct elf_phdr *eppnt, int prot, int type,
320 unsigned long total_size)
321 {
322 unsigned long map_addr;
323 unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
324 unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
325 addr = ELF_PAGESTART(addr);
326 size = ELF_PAGEALIGN(size);
327
328 /* mmap() will return -EINVAL if given a zero size, but a
329 * segment with zero filesize is perfectly valid */
330 if (!size)
331 return addr;
332
333 down_write(&current->mm->mmap_sem);
334 /*
335 * total_size is the size of the ELF (interpreter) image.
336 * The _first_ mmap needs to know the full size, otherwise
337 * randomization might put this image into an overlapping
338 * position with the ELF binary image. (since size < total_size)
339 * So we first map the 'big' image - and unmap the remainder at
340 * the end. (which unmap is needed for ELF images with holes.)
341 */
342 if (total_size) {
343 total_size = ELF_PAGEALIGN(total_size);
344 map_addr = do_mmap(filep, addr, total_size, prot, type, off);
345 if (!BAD_ADDR(map_addr))
346 do_munmap(current->mm, map_addr+size, total_size-size);
347 } else
348 map_addr = do_mmap(filep, addr, size, prot, type, off);
349
350 up_write(&current->mm->mmap_sem);
351 return(map_addr);
352 }
353
354 static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr)
355 {
356 int i, first_idx = -1, last_idx = -1;
357
358 for (i = 0; i < nr; i++) {
359 if (cmds[i].p_type == PT_LOAD) {
360 last_idx = i;
361 if (first_idx == -1)
362 first_idx = i;
363 }
364 }
365 if (first_idx == -1)
366 return 0;
367
368 return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz -
369 ELF_PAGESTART(cmds[first_idx].p_vaddr);
370 }
371
372
373 /* This is much more generalized than the library routine read function,
374 so we keep this separate. Technically the library read function
375 is only provided so that we can read a.out libraries that have
376 an ELF header */
377
378 static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
379 struct file *interpreter, unsigned long *interp_map_addr,
380 unsigned long no_base)
381 {
382 struct elf_phdr *elf_phdata;
383 struct elf_phdr *eppnt;
384 unsigned long load_addr = 0;
385 int load_addr_set = 0;
386 unsigned long last_bss = 0, elf_bss = 0;
387 unsigned long error = ~0UL;
388 unsigned long total_size;
389 int retval, i, size;
390
391 /* First of all, some simple consistency checks */
392 if (interp_elf_ex->e_type != ET_EXEC &&
393 interp_elf_ex->e_type != ET_DYN)
394 goto out;
395 if (!elf_check_arch(interp_elf_ex))
396 goto out;
397 if (!interpreter->f_op || !interpreter->f_op->mmap)
398 goto out;
399
400 /*
401 * If the size of this structure has changed, then punt, since
402 * we will be doing the wrong thing.
403 */
404 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
405 goto out;
406 if (interp_elf_ex->e_phnum < 1 ||
407 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
408 goto out;
409
410 /* Now read in all of the header information */
411 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
412 if (size > ELF_MIN_ALIGN)
413 goto out;
414 elf_phdata = kmalloc(size, GFP_KERNEL);
415 if (!elf_phdata)
416 goto out;
417
418 retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
419 (char *)elf_phdata, size);
420 error = -EIO;
421 if (retval != size) {
422 if (retval < 0)
423 error = retval;
424 goto out_close;
425 }
426
427 total_size = total_mapping_size(elf_phdata, interp_elf_ex->e_phnum);
428 if (!total_size) {
429 error = -EINVAL;
430 goto out_close;
431 }
432
433 eppnt = elf_phdata;
434 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
435 if (eppnt->p_type == PT_LOAD) {
436 int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
437 int elf_prot = 0;
438 unsigned long vaddr = 0;
439 unsigned long k, map_addr;
440
441 if (eppnt->p_flags & PF_R)
442 elf_prot = PROT_READ;
443 if (eppnt->p_flags & PF_W)
444 elf_prot |= PROT_WRITE;
445 if (eppnt->p_flags & PF_X)
446 elf_prot |= PROT_EXEC;
447 vaddr = eppnt->p_vaddr;
448 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
449 elf_type |= MAP_FIXED;
450 else if (no_base && interp_elf_ex->e_type == ET_DYN)
451 load_addr = -vaddr;
452
453 map_addr = elf_map(interpreter, load_addr + vaddr,
454 eppnt, elf_prot, elf_type, total_size);
455 total_size = 0;
456 if (!*interp_map_addr)
457 *interp_map_addr = map_addr;
458 error = map_addr;
459 if (BAD_ADDR(map_addr))
460 goto out_close;
461
462 if (!load_addr_set &&
463 interp_elf_ex->e_type == ET_DYN) {
464 load_addr = map_addr - ELF_PAGESTART(vaddr);
465 load_addr_set = 1;
466 }
467
468 /*
469 * Check to see if the section's size will overflow the
470 * allowed task size. Note that p_filesz must always be
471 * <= p_memsize so it's only necessary to check p_memsz.
472 */
473 k = load_addr + eppnt->p_vaddr;
474 if (BAD_ADDR(k) ||
475 eppnt->p_filesz > eppnt->p_memsz ||
476 eppnt->p_memsz > TASK_SIZE ||
477 TASK_SIZE - eppnt->p_memsz < k) {
478 error = -ENOMEM;
479 goto out_close;
480 }
481
482 /*
483 * Find the end of the file mapping for this phdr, and
484 * keep track of the largest address we see for this.
485 */
486 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
487 if (k > elf_bss)
488 elf_bss = k;
489
490 /*
491 * Do the same thing for the memory mapping - between
492 * elf_bss and last_bss is the bss section.
493 */
494 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
495 if (k > last_bss)
496 last_bss = k;
497 }
498 }
499
500 if (last_bss > elf_bss) {
501 /*
502 * Now fill out the bss section. First pad the last page up
503 * to the page boundary, and then perform a mmap to make sure
504 * that there are zero-mapped pages up to and including the
505 * last bss page.
506 */
507 if (padzero(elf_bss)) {
508 error = -EFAULT;
509 goto out_close;
510 }
511
512 /* What we have mapped so far */
513 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
514
515 /* Map the last of the bss segment */
516 down_write(&current->mm->mmap_sem);
517 error = do_brk(elf_bss, last_bss - elf_bss);
518 up_write(&current->mm->mmap_sem);
519 if (BAD_ADDR(error))
520 goto out_close;
521 }
522
523 error = load_addr;
524
525 out_close:
526 kfree(elf_phdata);
527 out:
528 return error;
529 }
530
531 /*
532 * These are the functions used to load ELF style executables and shared
533 * libraries. There is no binary dependent code anywhere else.
534 */
535
536 #define INTERPRETER_NONE 0
537 #define INTERPRETER_ELF 2
538
539 #ifndef STACK_RND_MASK
540 #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
541 #endif
542
543 static unsigned long randomize_stack_top(unsigned long stack_top)
544 {
545 unsigned int random_variable = 0;
546
547 if ((current->flags & PF_RANDOMIZE) &&
548 !(current->personality & ADDR_NO_RANDOMIZE)) {
549 random_variable = get_random_int() & STACK_RND_MASK;
550 random_variable <<= PAGE_SHIFT;
551 }
552 #ifdef CONFIG_STACK_GROWSUP
553 return PAGE_ALIGN(stack_top) + random_variable;
554 #else
555 return PAGE_ALIGN(stack_top) - random_variable;
556 #endif
557 }
558
559 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
560 {
561 struct file *interpreter = NULL; /* to shut gcc up */
562 unsigned long load_addr = 0, load_bias = 0;
563 int load_addr_set = 0;
564 char * elf_interpreter = NULL;
565 unsigned long error;
566 struct elf_phdr *elf_ppnt, *elf_phdata;
567 unsigned long elf_bss, elf_brk;
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 __maybe_unused = 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 elf_ppnt = elf_phdata;
623 elf_bss = 0;
624 elf_brk = 0;
625
626 start_code = ~0UL;
627 end_code = 0;
628 start_data = 0;
629 end_data = 0;
630
631 for (i = 0; i < loc->elf_ex.e_phnum; i++) {
632 if (elf_ppnt->p_type == PT_INTERP) {
633 /* This is the program interpreter used for
634 * shared libraries - for now assume that this
635 * is an a.out format binary
636 */
637 retval = -ENOEXEC;
638 if (elf_ppnt->p_filesz > PATH_MAX ||
639 elf_ppnt->p_filesz < 2)
640 goto out_free_ph;
641
642 retval = -ENOMEM;
643 elf_interpreter = kmalloc(elf_ppnt->p_filesz,
644 GFP_KERNEL);
645 if (!elf_interpreter)
646 goto out_free_ph;
647
648 retval = kernel_read(bprm->file, elf_ppnt->p_offset,
649 elf_interpreter,
650 elf_ppnt->p_filesz);
651 if (retval != elf_ppnt->p_filesz) {
652 if (retval >= 0)
653 retval = -EIO;
654 goto out_free_interp;
655 }
656 /* make sure path is NULL terminated */
657 retval = -ENOEXEC;
658 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
659 goto out_free_interp;
660
661 interpreter = open_exec(elf_interpreter);
662 retval = PTR_ERR(interpreter);
663 if (IS_ERR(interpreter))
664 goto out_free_interp;
665
666 /*
667 * If the binary is not readable then enforce
668 * mm->dumpable = 0 regardless of the interpreter's
669 * permissions.
670 */
671 would_dump(bprm, interpreter);
672
673 retval = kernel_read(interpreter, 0, bprm->buf,
674 BINPRM_BUF_SIZE);
675 if (retval != BINPRM_BUF_SIZE) {
676 if (retval >= 0)
677 retval = -EIO;
678 goto out_free_dentry;
679 }
680
681 /* Get the exec headers */
682 loc->interp_elf_ex = *((struct elfhdr *)bprm->buf);
683 break;
684 }
685 elf_ppnt++;
686 }
687
688 elf_ppnt = elf_phdata;
689 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
690 if (elf_ppnt->p_type == PT_GNU_STACK) {
691 if (elf_ppnt->p_flags & PF_X)
692 executable_stack = EXSTACK_ENABLE_X;
693 else
694 executable_stack = EXSTACK_DISABLE_X;
695 break;
696 }
697
698 /* Some simple consistency checks for the interpreter */
699 if (elf_interpreter) {
700 retval = -ELIBBAD;
701 /* Not an ELF interpreter */
702 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
703 goto out_free_dentry;
704 /* Verify the interpreter has a valid arch */
705 if (!elf_check_arch(&loc->interp_elf_ex))
706 goto out_free_dentry;
707 }
708
709 /* Flush all traces of the currently running executable */
710 retval = flush_old_exec(bprm);
711 if (retval)
712 goto out_free_dentry;
713
714 /* OK, This is the point of no return */
715 current->flags &= ~PF_FORKNOEXEC;
716 current->mm->def_flags = def_flags;
717
718 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
719 may depend on the personality. */
720 SET_PERSONALITY(loc->elf_ex);
721 if (elf_read_implies_exec(loc->elf_ex, executable_stack))
722 current->personality |= READ_IMPLIES_EXEC;
723
724 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
725 current->flags |= PF_RANDOMIZE;
726
727 setup_new_exec(bprm);
728
729 /* Do this so that we can load the interpreter, if need be. We will
730 change some of these later */
731 current->mm->free_area_cache = current->mm->mmap_base;
732 current->mm->cached_hole_size = 0;
733 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
734 executable_stack);
735 if (retval < 0) {
736 send_sig(SIGKILL, current, 0);
737 goto out_free_dentry;
738 }
739
740 current->mm->start_stack = bprm->p;
741
742 /* Now we do a little grungy work by mmapping the ELF image into
743 the correct location in memory. */
744 for(i = 0, elf_ppnt = elf_phdata;
745 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
746 int elf_prot = 0, elf_flags;
747 unsigned long k, vaddr;
748
749 if (elf_ppnt->p_type != PT_LOAD)
750 continue;
751
752 if (unlikely (elf_brk > elf_bss)) {
753 unsigned long nbyte;
754
755 /* There was a PT_LOAD segment with p_memsz > p_filesz
756 before this one. Map anonymous pages, if needed,
757 and clear the area. */
758 retval = set_brk(elf_bss + load_bias,
759 elf_brk + load_bias);
760 if (retval) {
761 send_sig(SIGKILL, current, 0);
762 goto out_free_dentry;
763 }
764 nbyte = ELF_PAGEOFFSET(elf_bss);
765 if (nbyte) {
766 nbyte = ELF_MIN_ALIGN - nbyte;
767 if (nbyte > elf_brk - elf_bss)
768 nbyte = elf_brk - elf_bss;
769 if (clear_user((void __user *)elf_bss +
770 load_bias, nbyte)) {
771 /*
772 * This bss-zeroing can fail if the ELF
773 * file specifies odd protections. So
774 * we don't check the return value
775 */
776 }
777 }
778 }
779
780 if (elf_ppnt->p_flags & PF_R)
781 elf_prot |= PROT_READ;
782 if (elf_ppnt->p_flags & PF_W)
783 elf_prot |= PROT_WRITE;
784 if (elf_ppnt->p_flags & PF_X)
785 elf_prot |= PROT_EXEC;
786
787 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
788
789 vaddr = elf_ppnt->p_vaddr;
790 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
791 elf_flags |= MAP_FIXED;
792 } else if (loc->elf_ex.e_type == ET_DYN) {
793 /* Try and get dynamic programs out of the way of the
794 * default mmap base, as well as whatever program they
795 * might try to exec. This is because the brk will
796 * follow the loader, and is not movable. */
797 #if defined(CONFIG_X86) || defined(CONFIG_ARM)
798 load_bias = 0;
799 #else
800 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
801 #endif
802 }
803
804 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
805 elf_prot, elf_flags, 0);
806 if (BAD_ADDR(error)) {
807 send_sig(SIGKILL, current, 0);
808 retval = IS_ERR((void *)error) ?
809 PTR_ERR((void*)error) : -EINVAL;
810 goto out_free_dentry;
811 }
812
813 if (!load_addr_set) {
814 load_addr_set = 1;
815 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
816 if (loc->elf_ex.e_type == ET_DYN) {
817 load_bias += error -
818 ELF_PAGESTART(load_bias + vaddr);
819 load_addr += load_bias;
820 reloc_func_desc = load_bias;
821 }
822 }
823 k = elf_ppnt->p_vaddr;
824 if (k < start_code)
825 start_code = k;
826 if (start_data < k)
827 start_data = k;
828
829 /*
830 * Check to see if the section's size will overflow the
831 * allowed task size. Note that p_filesz must always be
832 * <= p_memsz so it is only necessary to check p_memsz.
833 */
834 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
835 elf_ppnt->p_memsz > TASK_SIZE ||
836 TASK_SIZE - elf_ppnt->p_memsz < k) {
837 /* set_brk can never work. Avoid overflows. */
838 send_sig(SIGKILL, current, 0);
839 retval = -EINVAL;
840 goto out_free_dentry;
841 }
842
843 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
844
845 if (k > elf_bss)
846 elf_bss = k;
847 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
848 end_code = k;
849 if (end_data < k)
850 end_data = k;
851 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
852 if (k > elf_brk)
853 elf_brk = k;
854 }
855
856 loc->elf_ex.e_entry += load_bias;
857 elf_bss += load_bias;
858 elf_brk += load_bias;
859 start_code += load_bias;
860 end_code += load_bias;
861 start_data += load_bias;
862 end_data += load_bias;
863
864 /* Calling set_brk effectively mmaps the pages that we need
865 * for the bss and break sections. We must do this before
866 * mapping in the interpreter, to make sure it doesn't wind
867 * up getting placed where the bss needs to go.
868 */
869 retval = set_brk(elf_bss, elf_brk);
870 if (retval) {
871 send_sig(SIGKILL, current, 0);
872 goto out_free_dentry;
873 }
874 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
875 send_sig(SIGSEGV, current, 0);
876 retval = -EFAULT; /* Nobody gets to see this, but.. */
877 goto out_free_dentry;
878 }
879
880 if (elf_interpreter) {
881 unsigned long uninitialized_var(interp_map_addr);
882
883 elf_entry = load_elf_interp(&loc->interp_elf_ex,
884 interpreter,
885 &interp_map_addr,
886 load_bias);
887 if (!IS_ERR((void *)elf_entry)) {
888 /*
889 * load_elf_interp() returns relocation
890 * adjustment
891 */
892 interp_load_addr = elf_entry;
893 elf_entry += loc->interp_elf_ex.e_entry;
894 }
895 if (BAD_ADDR(elf_entry)) {
896 force_sig(SIGSEGV, current);
897 retval = IS_ERR((void *)elf_entry) ?
898 (int)elf_entry : -EINVAL;
899 goto out_free_dentry;
900 }
901 reloc_func_desc = interp_load_addr;
902
903 allow_write_access(interpreter);
904 fput(interpreter);
905 kfree(elf_interpreter);
906 } else {
907 elf_entry = loc->elf_ex.e_entry;
908 if (BAD_ADDR(elf_entry)) {
909 force_sig(SIGSEGV, current);
910 retval = -EINVAL;
911 goto out_free_dentry;
912 }
913 }
914
915 kfree(elf_phdata);
916
917 set_binfmt(&elf_format);
918
919 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
920 retval = arch_setup_additional_pages(bprm, !!elf_interpreter);
921 if (retval < 0) {
922 send_sig(SIGKILL, current, 0);
923 goto out;
924 }
925 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
926
927 install_exec_creds(bprm);
928 current->flags &= ~PF_FORKNOEXEC;
929 retval = create_elf_tables(bprm, &loc->elf_ex,
930 load_addr, interp_load_addr);
931 if (retval < 0) {
932 send_sig(SIGKILL, current, 0);
933 goto out;
934 }
935 /* N.B. passed_fileno might not be initialized? */
936 current->mm->end_code = end_code;
937 current->mm->start_code = start_code;
938 current->mm->start_data = start_data;
939 current->mm->end_data = end_data;
940 current->mm->start_stack = bprm->p;
941
942 #ifdef arch_randomize_brk
943 if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) {
944 current->mm->brk = current->mm->start_brk =
945 arch_randomize_brk(current->mm);
946 #ifdef CONFIG_COMPAT_BRK
947 current->brk_randomized = 1;
948 #endif
949 }
950 #endif
951
952 if (current->personality & MMAP_PAGE_ZERO) {
953 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
954 and some applications "depend" upon this behavior.
955 Since we do not have the power to recompile these, we
956 emulate the SVr4 behavior. Sigh. */
957 down_write(&current->mm->mmap_sem);
958 error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
959 MAP_FIXED | MAP_PRIVATE, 0);
960 up_write(&current->mm->mmap_sem);
961 }
962
963 #ifdef ELF_PLAT_INIT
964 /*
965 * The ABI may specify that certain registers be set up in special
966 * ways (on i386 %edx is the address of a DT_FINI function, for
967 * example. In addition, it may also specify (eg, PowerPC64 ELF)
968 * that the e_entry field is the address of the function descriptor
969 * for the startup routine, rather than the address of the startup
970 * routine itself. This macro performs whatever initialization to
971 * the regs structure is required as well as any relocations to the
972 * function descriptor entries when executing dynamically links apps.
973 */
974 ELF_PLAT_INIT(regs, reloc_func_desc);
975 #endif
976
977 start_thread(regs, elf_entry, bprm->p);
978 retval = 0;
979 out:
980 kfree(loc);
981 out_ret:
982 return retval;
983
984 /* error cleanup */
985 out_free_dentry:
986 allow_write_access(interpreter);
987 if (interpreter)
988 fput(interpreter);
989 out_free_interp:
990 kfree(elf_interpreter);
991 out_free_ph:
992 kfree(elf_phdata);
993 goto out;
994 }
995
996 /* This is really simpleminded and specialized - we are loading an
997 a.out library that is given an ELF header. */
998 static int load_elf_library(struct file *file)
999 {
1000 struct elf_phdr *elf_phdata;
1001 struct elf_phdr *eppnt;
1002 unsigned long elf_bss, bss, len;
1003 int retval, error, i, j;
1004 struct elfhdr elf_ex;
1005
1006 error = -ENOEXEC;
1007 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
1008 if (retval != sizeof(elf_ex))
1009 goto out;
1010
1011 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
1012 goto out;
1013
1014 /* First of all, some simple consistency checks */
1015 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
1016 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
1017 goto out;
1018
1019 /* Now read in all of the header information */
1020
1021 j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
1022 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1023
1024 error = -ENOMEM;
1025 elf_phdata = kmalloc(j, GFP_KERNEL);
1026 if (!elf_phdata)
1027 goto out;
1028
1029 eppnt = elf_phdata;
1030 error = -ENOEXEC;
1031 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
1032 if (retval != j)
1033 goto out_free_ph;
1034
1035 for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
1036 if ((eppnt + i)->p_type == PT_LOAD)
1037 j++;
1038 if (j != 1)
1039 goto out_free_ph;
1040
1041 while (eppnt->p_type != PT_LOAD)
1042 eppnt++;
1043
1044 /* Now use mmap to map the library into memory. */
1045 down_write(&current->mm->mmap_sem);
1046 error = do_mmap(file,
1047 ELF_PAGESTART(eppnt->p_vaddr),
1048 (eppnt->p_filesz +
1049 ELF_PAGEOFFSET(eppnt->p_vaddr)),
1050 PROT_READ | PROT_WRITE | PROT_EXEC,
1051 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
1052 (eppnt->p_offset -
1053 ELF_PAGEOFFSET(eppnt->p_vaddr)));
1054 up_write(&current->mm->mmap_sem);
1055 if (error != ELF_PAGESTART(eppnt->p_vaddr))
1056 goto out_free_ph;
1057
1058 elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
1059 if (padzero(elf_bss)) {
1060 error = -EFAULT;
1061 goto out_free_ph;
1062 }
1063
1064 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
1065 ELF_MIN_ALIGN - 1);
1066 bss = eppnt->p_memsz + eppnt->p_vaddr;
1067 if (bss > len) {
1068 down_write(&current->mm->mmap_sem);
1069 do_brk(len, bss - len);
1070 up_write(&current->mm->mmap_sem);
1071 }
1072 error = 0;
1073
1074 out_free_ph:
1075 kfree(elf_phdata);
1076 out:
1077 return error;
1078 }
1079
1080 #ifdef CONFIG_ELF_CORE
1081 /*
1082 * ELF core dumper
1083 *
1084 * Modelled on fs/exec.c:aout_core_dump()
1085 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1086 */
1087
1088 /*
1089 * Decide what to dump of a segment, part, all or none.
1090 */
1091 static unsigned long vma_dump_size(struct vm_area_struct *vma,
1092 unsigned long mm_flags)
1093 {
1094 #define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1095
1096 /* The vma can be set up to tell us the answer directly. */
1097 if (vma->vm_flags & VM_ALWAYSDUMP)
1098 goto whole;
1099
1100 /* Hugetlb memory check */
1101 if (vma->vm_flags & VM_HUGETLB) {
1102 if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
1103 goto whole;
1104 if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
1105 goto whole;
1106 }
1107
1108 /* Do not dump I/O mapped devices or special mappings */
1109 if (vma->vm_flags & (VM_IO | VM_RESERVED))
1110 return 0;
1111
1112 /* By default, dump shared memory if mapped from an anonymous file. */
1113 if (vma->vm_flags & VM_SHARED) {
1114 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ?
1115 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
1116 goto whole;
1117 return 0;
1118 }
1119
1120 /* Dump segments that have been written to. */
1121 if (vma->anon_vma && FILTER(ANON_PRIVATE))
1122 goto whole;
1123 if (vma->vm_file == NULL)
1124 return 0;
1125
1126 if (FILTER(MAPPED_PRIVATE))
1127 goto whole;
1128
1129 /*
1130 * If this looks like the beginning of a DSO or executable mapping,
1131 * check for an ELF header. If we find one, dump the first page to
1132 * aid in determining what was mapped here.
1133 */
1134 if (FILTER(ELF_HEADERS) &&
1135 vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
1136 u32 __user *header = (u32 __user *) vma->vm_start;
1137 u32 word;
1138 mm_segment_t fs = get_fs();
1139 /*
1140 * Doing it this way gets the constant folded by GCC.
1141 */
1142 union {
1143 u32 cmp;
1144 char elfmag[SELFMAG];
1145 } magic;
1146 BUILD_BUG_ON(SELFMAG != sizeof word);
1147 magic.elfmag[EI_MAG0] = ELFMAG0;
1148 magic.elfmag[EI_MAG1] = ELFMAG1;
1149 magic.elfmag[EI_MAG2] = ELFMAG2;
1150 magic.elfmag[EI_MAG3] = ELFMAG3;
1151 /*
1152 * Switch to the user "segment" for get_user(),
1153 * then put back what elf_core_dump() had in place.
1154 */
1155 set_fs(USER_DS);
1156 if (unlikely(get_user(word, header)))
1157 word = 0;
1158 set_fs(fs);
1159 if (word == magic.cmp)
1160 return PAGE_SIZE;
1161 }
1162
1163 #undef FILTER
1164
1165 return 0;
1166
1167 whole:
1168 return vma->vm_end - vma->vm_start;
1169 }
1170
1171 /* An ELF note in memory */
1172 struct memelfnote
1173 {
1174 const char *name;
1175 int type;
1176 unsigned int datasz;
1177 void *data;
1178 };
1179
1180 static int notesize(struct memelfnote *en)
1181 {
1182 int sz;
1183
1184 sz = sizeof(struct elf_note);
1185 sz += roundup(strlen(en->name) + 1, 4);
1186 sz += roundup(en->datasz, 4);
1187
1188 return sz;
1189 }
1190
1191 #define DUMP_WRITE(addr, nr, foffset) \
1192 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
1193
1194 static int alignfile(struct file *file, loff_t *foffset)
1195 {
1196 static const char buf[4] = { 0, };
1197 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
1198 return 1;
1199 }
1200
1201 static int writenote(struct memelfnote *men, struct file *file,
1202 loff_t *foffset)
1203 {
1204 struct elf_note en;
1205 en.n_namesz = strlen(men->name) + 1;
1206 en.n_descsz = men->datasz;
1207 en.n_type = men->type;
1208
1209 DUMP_WRITE(&en, sizeof(en), foffset);
1210 DUMP_WRITE(men->name, en.n_namesz, foffset);
1211 if (!alignfile(file, foffset))
1212 return 0;
1213 DUMP_WRITE(men->data, men->datasz, foffset);
1214 if (!alignfile(file, foffset))
1215 return 0;
1216
1217 return 1;
1218 }
1219 #undef DUMP_WRITE
1220
1221 static void fill_elf_header(struct elfhdr *elf, int segs,
1222 u16 machine, u32 flags, u8 osabi)
1223 {
1224 memset(elf, 0, sizeof(*elf));
1225
1226 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1227 elf->e_ident[EI_CLASS] = ELF_CLASS;
1228 elf->e_ident[EI_DATA] = ELF_DATA;
1229 elf->e_ident[EI_VERSION] = EV_CURRENT;
1230 elf->e_ident[EI_OSABI] = ELF_OSABI;
1231
1232 elf->e_type = ET_CORE;
1233 elf->e_machine = machine;
1234 elf->e_version = EV_CURRENT;
1235 elf->e_phoff = sizeof(struct elfhdr);
1236 elf->e_flags = flags;
1237 elf->e_ehsize = sizeof(struct elfhdr);
1238 elf->e_phentsize = sizeof(struct elf_phdr);
1239 elf->e_phnum = segs;
1240
1241 return;
1242 }
1243
1244 static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
1245 {
1246 phdr->p_type = PT_NOTE;
1247 phdr->p_offset = offset;
1248 phdr->p_vaddr = 0;
1249 phdr->p_paddr = 0;
1250 phdr->p_filesz = sz;
1251 phdr->p_memsz = 0;
1252 phdr->p_flags = 0;
1253 phdr->p_align = 0;
1254 return;
1255 }
1256
1257 static void fill_note(struct memelfnote *note, const char *name, int type,
1258 unsigned int sz, void *data)
1259 {
1260 note->name = name;
1261 note->type = type;
1262 note->datasz = sz;
1263 note->data = data;
1264 return;
1265 }
1266
1267 /*
1268 * fill up all the fields in prstatus from the given task struct, except
1269 * registers which need to be filled up separately.
1270 */
1271 static void fill_prstatus(struct elf_prstatus *prstatus,
1272 struct task_struct *p, long signr)
1273 {
1274 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1275 prstatus->pr_sigpend = p->pending.signal.sig[0];
1276 prstatus->pr_sighold = p->blocked.sig[0];
1277 rcu_read_lock();
1278 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1279 rcu_read_unlock();
1280 prstatus->pr_pid = task_pid_vnr(p);
1281 prstatus->pr_pgrp = task_pgrp_vnr(p);
1282 prstatus->pr_sid = task_session_vnr(p);
1283 if (thread_group_leader(p)) {
1284 struct task_cputime cputime;
1285
1286 /*
1287 * This is the record for the group leader. It shows the
1288 * group-wide total, not its individual thread total.
1289 */
1290 thread_group_cputime(p, &cputime);
1291 cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
1292 cputime_to_timeval(cputime.stime, &prstatus->pr_stime);
1293 } else {
1294 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1295 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1296 }
1297 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1298 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1299 }
1300
1301 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1302 struct mm_struct *mm)
1303 {
1304 const struct cred *cred;
1305 unsigned int i, len;
1306
1307 /* first copy the parameters from user space */
1308 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1309
1310 len = mm->arg_end - mm->arg_start;
1311 if (len >= ELF_PRARGSZ)
1312 len = ELF_PRARGSZ-1;
1313 if (copy_from_user(&psinfo->pr_psargs,
1314 (const char __user *)mm->arg_start, len))
1315 return -EFAULT;
1316 for(i = 0; i < len; i++)
1317 if (psinfo->pr_psargs[i] == 0)
1318 psinfo->pr_psargs[i] = ' ';
1319 psinfo->pr_psargs[len] = 0;
1320
1321 rcu_read_lock();
1322 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1323 rcu_read_unlock();
1324 psinfo->pr_pid = task_pid_vnr(p);
1325 psinfo->pr_pgrp = task_pgrp_vnr(p);
1326 psinfo->pr_sid = task_session_vnr(p);
1327
1328 i = p->state ? ffz(~p->state) + 1 : 0;
1329 psinfo->pr_state = i;
1330 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
1331 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1332 psinfo->pr_nice = task_nice(p);
1333 psinfo->pr_flag = p->flags;
1334 rcu_read_lock();
1335 cred = __task_cred(p);
1336 SET_UID(psinfo->pr_uid, cred->uid);
1337 SET_GID(psinfo->pr_gid, cred->gid);
1338 rcu_read_unlock();
1339 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1340
1341 return 0;
1342 }
1343
1344 static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
1345 {
1346 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
1347 int i = 0;
1348 do
1349 i += 2;
1350 while (auxv[i - 2] != AT_NULL);
1351 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
1352 }
1353
1354 #ifdef CORE_DUMP_USE_REGSET
1355 #include <linux/regset.h>
1356
1357 struct elf_thread_core_info {
1358 struct elf_thread_core_info *next;
1359 struct task_struct *task;
1360 struct elf_prstatus prstatus;
1361 struct memelfnote notes[0];
1362 };
1363
1364 struct elf_note_info {
1365 struct elf_thread_core_info *thread;
1366 struct memelfnote psinfo;
1367 struct memelfnote auxv;
1368 size_t size;
1369 int thread_notes;
1370 };
1371
1372 /*
1373 * When a regset has a writeback hook, we call it on each thread before
1374 * dumping user memory. On register window machines, this makes sure the
1375 * user memory backing the register data is up to date before we read it.
1376 */
1377 static void do_thread_regset_writeback(struct task_struct *task,
1378 const struct user_regset *regset)
1379 {
1380 if (regset->writeback)
1381 regset->writeback(task, regset, 1);
1382 }
1383
1384 static int fill_thread_core_info(struct elf_thread_core_info *t,
1385 const struct user_regset_view *view,
1386 long signr, size_t *total)
1387 {
1388 unsigned int i;
1389
1390 /*
1391 * NT_PRSTATUS is the one special case, because the regset data
1392 * goes into the pr_reg field inside the note contents, rather
1393 * than being the whole note contents. We fill the reset in here.
1394 * We assume that regset 0 is NT_PRSTATUS.
1395 */
1396 fill_prstatus(&t->prstatus, t->task, signr);
1397 (void) view->regsets[0].get(t->task, &view->regsets[0],
1398 0, sizeof(t->prstatus.pr_reg),
1399 &t->prstatus.pr_reg, NULL);
1400
1401 fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
1402 sizeof(t->prstatus), &t->prstatus);
1403 *total += notesize(&t->notes[0]);
1404
1405 do_thread_regset_writeback(t->task, &view->regsets[0]);
1406
1407 /*
1408 * Each other regset might generate a note too. For each regset
1409 * that has no core_note_type or is inactive, we leave t->notes[i]
1410 * all zero and we'll know to skip writing it later.
1411 */
1412 for (i = 1; i < view->n; ++i) {
1413 const struct user_regset *regset = &view->regsets[i];
1414 do_thread_regset_writeback(t->task, regset);
1415 if (regset->core_note_type &&
1416 (!regset->active || regset->active(t->task, regset))) {
1417 int ret;
1418 size_t size = regset->n * regset->size;
1419 void *data = kmalloc(size, GFP_KERNEL);
1420 if (unlikely(!data))
1421 return 0;
1422 ret = regset->get(t->task, regset,
1423 0, size, data, NULL);
1424 if (unlikely(ret))
1425 kfree(data);
1426 else {
1427 if (regset->core_note_type != NT_PRFPREG)
1428 fill_note(&t->notes[i], "LINUX",
1429 regset->core_note_type,
1430 size, data);
1431 else {
1432 t->prstatus.pr_fpvalid = 1;
1433 fill_note(&t->notes[i], "CORE",
1434 NT_PRFPREG, size, data);
1435 }
1436 *total += notesize(&t->notes[i]);
1437 }
1438 }
1439 }
1440
1441 return 1;
1442 }
1443
1444 static int fill_note_info(struct elfhdr *elf, int phdrs,
1445 struct elf_note_info *info,
1446 long signr, struct pt_regs *regs)
1447 {
1448 struct task_struct *dump_task = current;
1449 const struct user_regset_view *view = task_user_regset_view(dump_task);
1450 struct elf_thread_core_info *t;
1451 struct elf_prpsinfo *psinfo;
1452 struct core_thread *ct;
1453 unsigned int i;
1454
1455 info->size = 0;
1456 info->thread = NULL;
1457
1458 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1459 if (psinfo == NULL)
1460 return 0;
1461
1462 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1463
1464 /*
1465 * Figure out how many notes we're going to need for each thread.
1466 */
1467 info->thread_notes = 0;
1468 for (i = 0; i < view->n; ++i)
1469 if (view->regsets[i].core_note_type != 0)
1470 ++info->thread_notes;
1471
1472 /*
1473 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1474 * since it is our one special case.
1475 */
1476 if (unlikely(info->thread_notes == 0) ||
1477 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
1478 WARN_ON(1);
1479 return 0;
1480 }
1481
1482 /*
1483 * Initialize the ELF file header.
1484 */
1485 fill_elf_header(elf, phdrs,
1486 view->e_machine, view->e_flags, view->ei_osabi);
1487
1488 /*
1489 * Allocate a structure for each thread.
1490 */
1491 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) {
1492 t = kzalloc(offsetof(struct elf_thread_core_info,
1493 notes[info->thread_notes]),
1494 GFP_KERNEL);
1495 if (unlikely(!t))
1496 return 0;
1497
1498 t->task = ct->task;
1499 if (ct->task == dump_task || !info->thread) {
1500 t->next = info->thread;
1501 info->thread = t;
1502 } else {
1503 /*
1504 * Make sure to keep the original task at
1505 * the head of the list.
1506 */
1507 t->next = info->thread->next;
1508 info->thread->next = t;
1509 }
1510 }
1511
1512 /*
1513 * Now fill in each thread's information.
1514 */
1515 for (t = info->thread; t != NULL; t = t->next)
1516 if (!fill_thread_core_info(t, view, signr, &info->size))
1517 return 0;
1518
1519 /*
1520 * Fill in the two process-wide notes.
1521 */
1522 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
1523 info->size += notesize(&info->psinfo);
1524
1525 fill_auxv_note(&info->auxv, current->mm);
1526 info->size += notesize(&info->auxv);
1527
1528 return 1;
1529 }
1530
1531 static size_t get_note_info_size(struct elf_note_info *info)
1532 {
1533 return info->size;
1534 }
1535
1536 /*
1537 * Write all the notes for each thread. When writing the first thread, the
1538 * process-wide notes are interleaved after the first thread-specific note.
1539 */
1540 static int write_note_info(struct elf_note_info *info,
1541 struct file *file, loff_t *foffset)
1542 {
1543 bool first = 1;
1544 struct elf_thread_core_info *t = info->thread;
1545
1546 do {
1547 int i;
1548
1549 if (!writenote(&t->notes[0], file, foffset))
1550 return 0;
1551
1552 if (first && !writenote(&info->psinfo, file, foffset))
1553 return 0;
1554 if (first && !writenote(&info->auxv, file, foffset))
1555 return 0;
1556
1557 for (i = 1; i < info->thread_notes; ++i)
1558 if (t->notes[i].data &&
1559 !writenote(&t->notes[i], file, foffset))
1560 return 0;
1561
1562 first = 0;
1563 t = t->next;
1564 } while (t);
1565
1566 return 1;
1567 }
1568
1569 static void free_note_info(struct elf_note_info *info)
1570 {
1571 struct elf_thread_core_info *threads = info->thread;
1572 while (threads) {
1573 unsigned int i;
1574 struct elf_thread_core_info *t = threads;
1575 threads = t->next;
1576 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
1577 for (i = 1; i < info->thread_notes; ++i)
1578 kfree(t->notes[i].data);
1579 kfree(t);
1580 }
1581 kfree(info->psinfo.data);
1582 }
1583
1584 #else
1585
1586 /* Here is the structure in which status of each thread is captured. */
1587 struct elf_thread_status
1588 {
1589 struct list_head list;
1590 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1591 elf_fpregset_t fpu; /* NT_PRFPREG */
1592 struct task_struct *thread;
1593 #ifdef ELF_CORE_COPY_XFPREGS
1594 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
1595 #endif
1596 struct memelfnote notes[3];
1597 int num_notes;
1598 };
1599
1600 /*
1601 * In order to add the specific thread information for the elf file format,
1602 * we need to keep a linked list of every threads pr_status and then create
1603 * a single section for them in the final core file.
1604 */
1605 static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1606 {
1607 int sz = 0;
1608 struct task_struct *p = t->thread;
1609 t->num_notes = 0;
1610
1611 fill_prstatus(&t->prstatus, p, signr);
1612 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1613
1614 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1615 &(t->prstatus));
1616 t->num_notes++;
1617 sz += notesize(&t->notes[0]);
1618
1619 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1620 &t->fpu))) {
1621 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1622 &(t->fpu));
1623 t->num_notes++;
1624 sz += notesize(&t->notes[1]);
1625 }
1626
1627 #ifdef ELF_CORE_COPY_XFPREGS
1628 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
1629 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1630 sizeof(t->xfpu), &t->xfpu);
1631 t->num_notes++;
1632 sz += notesize(&t->notes[2]);
1633 }
1634 #endif
1635 return sz;
1636 }
1637
1638 struct elf_note_info {
1639 struct memelfnote *notes;
1640 struct elf_prstatus *prstatus; /* NT_PRSTATUS */
1641 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */
1642 struct list_head thread_list;
1643 elf_fpregset_t *fpu;
1644 #ifdef ELF_CORE_COPY_XFPREGS
1645 elf_fpxregset_t *xfpu;
1646 #endif
1647 int thread_status_size;
1648 int numnote;
1649 };
1650
1651 static int elf_note_info_init(struct elf_note_info *info)
1652 {
1653 memset(info, 0, sizeof(*info));
1654 INIT_LIST_HEAD(&info->thread_list);
1655
1656 /* Allocate space for six ELF notes */
1657 info->notes = kmalloc(6 * sizeof(struct memelfnote), GFP_KERNEL);
1658 if (!info->notes)
1659 return 0;
1660 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
1661 if (!info->psinfo)
1662 goto notes_free;
1663 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
1664 if (!info->prstatus)
1665 goto psinfo_free;
1666 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
1667 if (!info->fpu)
1668 goto prstatus_free;
1669 #ifdef ELF_CORE_COPY_XFPREGS
1670 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
1671 if (!info->xfpu)
1672 goto fpu_free;
1673 #endif
1674 return 1;
1675 #ifdef ELF_CORE_COPY_XFPREGS
1676 fpu_free:
1677 kfree(info->fpu);
1678 #endif
1679 prstatus_free:
1680 kfree(info->prstatus);
1681 psinfo_free:
1682 kfree(info->psinfo);
1683 notes_free:
1684 kfree(info->notes);
1685 return 0;
1686 }
1687
1688 static int fill_note_info(struct elfhdr *elf, int phdrs,
1689 struct elf_note_info *info,
1690 long signr, struct pt_regs *regs)
1691 {
1692 struct list_head *t;
1693
1694 if (!elf_note_info_init(info))
1695 return 0;
1696
1697 if (signr) {
1698 struct core_thread *ct;
1699 struct elf_thread_status *ets;
1700
1701 for (ct = current->mm->core_state->dumper.next;
1702 ct; ct = ct->next) {
1703 ets = kzalloc(sizeof(*ets), GFP_KERNEL);
1704 if (!ets)
1705 return 0;
1706
1707 ets->thread = ct->task;
1708 list_add(&ets->list, &info->thread_list);
1709 }
1710
1711 list_for_each(t, &info->thread_list) {
1712 int sz;
1713
1714 ets = list_entry(t, struct elf_thread_status, list);
1715 sz = elf_dump_thread_status(signr, ets);
1716 info->thread_status_size += sz;
1717 }
1718 }
1719 /* now collect the dump for the current */
1720 memset(info->prstatus, 0, sizeof(*info->prstatus));
1721 fill_prstatus(info->prstatus, current, signr);
1722 elf_core_copy_regs(&info->prstatus->pr_reg, regs);
1723
1724 /* Set up header */
1725 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI);
1726
1727 /*
1728 * Set up the notes in similar form to SVR4 core dumps made
1729 * with info from their /proc.
1730 */
1731
1732 fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
1733 sizeof(*info->prstatus), info->prstatus);
1734 fill_psinfo(info->psinfo, current->group_leader, current->mm);
1735 fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
1736 sizeof(*info->psinfo), info->psinfo);
1737
1738 info->numnote = 2;
1739
1740 fill_auxv_note(&info->notes[info->numnote++], current->mm);
1741
1742 /* Try to dump the FPU. */
1743 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
1744 info->fpu);
1745 if (info->prstatus->pr_fpvalid)
1746 fill_note(info->notes + info->numnote++,
1747 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
1748 #ifdef ELF_CORE_COPY_XFPREGS
1749 if (elf_core_copy_task_xfpregs(current, info->xfpu))
1750 fill_note(info->notes + info->numnote++,
1751 "LINUX", ELF_CORE_XFPREG_TYPE,
1752 sizeof(*info->xfpu), info->xfpu);
1753 #endif
1754
1755 return 1;
1756 }
1757
1758 static size_t get_note_info_size(struct elf_note_info *info)
1759 {
1760 int sz = 0;
1761 int i;
1762
1763 for (i = 0; i < info->numnote; i++)
1764 sz += notesize(info->notes + i);
1765
1766 sz += info->thread_status_size;
1767
1768 return sz;
1769 }
1770
1771 static int write_note_info(struct elf_note_info *info,
1772 struct file *file, loff_t *foffset)
1773 {
1774 int i;
1775 struct list_head *t;
1776
1777 for (i = 0; i < info->numnote; i++)
1778 if (!writenote(info->notes + i, file, foffset))
1779 return 0;
1780
1781 /* write out the thread status notes section */
1782 list_for_each(t, &info->thread_list) {
1783 struct elf_thread_status *tmp =
1784 list_entry(t, struct elf_thread_status, list);
1785
1786 for (i = 0; i < tmp->num_notes; i++)
1787 if (!writenote(&tmp->notes[i], file, foffset))
1788 return 0;
1789 }
1790
1791 return 1;
1792 }
1793
1794 static void free_note_info(struct elf_note_info *info)
1795 {
1796 while (!list_empty(&info->thread_list)) {
1797 struct list_head *tmp = info->thread_list.next;
1798 list_del(tmp);
1799 kfree(list_entry(tmp, struct elf_thread_status, list));
1800 }
1801
1802 kfree(info->prstatus);
1803 kfree(info->psinfo);
1804 kfree(info->notes);
1805 kfree(info->fpu);
1806 #ifdef ELF_CORE_COPY_XFPREGS
1807 kfree(info->xfpu);
1808 #endif
1809 }
1810
1811 #endif
1812
1813 static struct vm_area_struct *first_vma(struct task_struct *tsk,
1814 struct vm_area_struct *gate_vma)
1815 {
1816 struct vm_area_struct *ret = tsk->mm->mmap;
1817
1818 if (ret)
1819 return ret;
1820 return gate_vma;
1821 }
1822 /*
1823 * Helper function for iterating across a vma list. It ensures that the caller
1824 * will visit `gate_vma' prior to terminating the search.
1825 */
1826 static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma,
1827 struct vm_area_struct *gate_vma)
1828 {
1829 struct vm_area_struct *ret;
1830
1831 ret = this_vma->vm_next;
1832 if (ret)
1833 return ret;
1834 if (this_vma == gate_vma)
1835 return NULL;
1836 return gate_vma;
1837 }
1838
1839 static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
1840 elf_addr_t e_shoff, int segs)
1841 {
1842 elf->e_shoff = e_shoff;
1843 elf->e_shentsize = sizeof(*shdr4extnum);
1844 elf->e_shnum = 1;
1845 elf->e_shstrndx = SHN_UNDEF;
1846
1847 memset(shdr4extnum, 0, sizeof(*shdr4extnum));
1848
1849 shdr4extnum->sh_type = SHT_NULL;
1850 shdr4extnum->sh_size = elf->e_shnum;
1851 shdr4extnum->sh_link = elf->e_shstrndx;
1852 shdr4extnum->sh_info = segs;
1853 }
1854
1855 static size_t elf_core_vma_data_size(struct vm_area_struct *gate_vma,
1856 unsigned long mm_flags)
1857 {
1858 struct vm_area_struct *vma;
1859 size_t size = 0;
1860
1861 for (vma = first_vma(current, gate_vma); vma != NULL;
1862 vma = next_vma(vma, gate_vma))
1863 size += vma_dump_size(vma, mm_flags);
1864 return size;
1865 }
1866
1867 /*
1868 * Actual dumper
1869 *
1870 * This is a two-pass process; first we find the offsets of the bits,
1871 * and then they are actually written out. If we run out of core limit
1872 * we just truncate.
1873 */
1874 static int elf_core_dump(struct coredump_params *cprm)
1875 {
1876 int has_dumped = 0;
1877 mm_segment_t fs;
1878 int segs;
1879 size_t size = 0;
1880 struct vm_area_struct *vma, *gate_vma;
1881 struct elfhdr *elf = NULL;
1882 loff_t offset = 0, dataoff, foffset;
1883 struct elf_note_info info;
1884 struct elf_phdr *phdr4note = NULL;
1885 struct elf_shdr *shdr4extnum = NULL;
1886 Elf_Half e_phnum;
1887 elf_addr_t e_shoff;
1888
1889 /*
1890 * We no longer stop all VM operations.
1891 *
1892 * This is because those proceses that could possibly change map_count
1893 * or the mmap / vma pages are now blocked in do_exit on current
1894 * finishing this core dump.
1895 *
1896 * Only ptrace can touch these memory addresses, but it doesn't change
1897 * the map_count or the pages allocated. So no possibility of crashing
1898 * exists while dumping the mm->vm_next areas to the core file.
1899 */
1900
1901 /* alloc memory for large data structures: too large to be on stack */
1902 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
1903 if (!elf)
1904 goto out;
1905 /*
1906 * The number of segs are recored into ELF header as 16bit value.
1907 * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
1908 */
1909 segs = current->mm->map_count;
1910 segs += elf_core_extra_phdrs();
1911
1912 gate_vma = get_gate_vma(current->mm);
1913 if (gate_vma != NULL)
1914 segs++;
1915
1916 /* for notes section */
1917 segs++;
1918
1919 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
1920 * this, kernel supports extended numbering. Have a look at
1921 * include/linux/elf.h for further information. */
1922 e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
1923
1924 /*
1925 * Collect all the non-memory information about the process for the
1926 * notes. This also sets up the file header.
1927 */
1928 if (!fill_note_info(elf, e_phnum, &info, cprm->signr, cprm->regs))
1929 goto cleanup;
1930
1931 has_dumped = 1;
1932 current->flags |= PF_DUMPCORE;
1933
1934 fs = get_fs();
1935 set_fs(KERNEL_DS);
1936
1937 offset += sizeof(*elf); /* Elf header */
1938 offset += segs * sizeof(struct elf_phdr); /* Program headers */
1939 foffset = offset;
1940
1941 /* Write notes phdr entry */
1942 {
1943 size_t sz = get_note_info_size(&info);
1944
1945 sz += elf_coredump_extra_notes_size();
1946
1947 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
1948 if (!phdr4note)
1949 goto end_coredump;
1950
1951 fill_elf_note_phdr(phdr4note, sz, offset);
1952 offset += sz;
1953 }
1954
1955 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
1956
1957 offset += elf_core_vma_data_size(gate_vma, cprm->mm_flags);
1958 offset += elf_core_extra_data_size();
1959 e_shoff = offset;
1960
1961 if (e_phnum == PN_XNUM) {
1962 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
1963 if (!shdr4extnum)
1964 goto end_coredump;
1965 fill_extnum_info(elf, shdr4extnum, e_shoff, segs);
1966 }
1967
1968 offset = dataoff;
1969
1970 size += sizeof(*elf);
1971 if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
1972 goto end_coredump;
1973
1974 size += sizeof(*phdr4note);
1975 if (size > cprm->limit
1976 || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note)))
1977 goto end_coredump;
1978
1979 /* Write program headers for segments dump */
1980 for (vma = first_vma(current, gate_vma); vma != NULL;
1981 vma = next_vma(vma, gate_vma)) {
1982 struct elf_phdr phdr;
1983
1984 phdr.p_type = PT_LOAD;
1985 phdr.p_offset = offset;
1986 phdr.p_vaddr = vma->vm_start;
1987 phdr.p_paddr = 0;
1988 phdr.p_filesz = vma_dump_size(vma, cprm->mm_flags);
1989 phdr.p_memsz = vma->vm_end - vma->vm_start;
1990 offset += phdr.p_filesz;
1991 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
1992 if (vma->vm_flags & VM_WRITE)
1993 phdr.p_flags |= PF_W;
1994 if (vma->vm_flags & VM_EXEC)
1995 phdr.p_flags |= PF_X;
1996 phdr.p_align = ELF_EXEC_PAGESIZE;
1997
1998 size += sizeof(phdr);
1999 if (size > cprm->limit
2000 || !dump_write(cprm->file, &phdr, sizeof(phdr)))
2001 goto end_coredump;
2002 }
2003
2004 if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit))
2005 goto end_coredump;
2006
2007 /* write out the notes section */
2008 if (!write_note_info(&info, cprm->file, &foffset))
2009 goto end_coredump;
2010
2011 if (elf_coredump_extra_notes_write(cprm->file, &foffset))
2012 goto end_coredump;
2013
2014 /* Align to page */
2015 if (!dump_seek(cprm->file, dataoff - foffset))
2016 goto end_coredump;
2017
2018 for (vma = first_vma(current, gate_vma); vma != NULL;
2019 vma = next_vma(vma, gate_vma)) {
2020 unsigned long addr;
2021 unsigned long end;
2022
2023 end = vma->vm_start + vma_dump_size(vma, cprm->mm_flags);
2024
2025 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
2026 struct page *page;
2027 int stop;
2028
2029 page = get_dump_page(addr);
2030 if (page) {
2031 void *kaddr = kmap(page);
2032 stop = ((size += PAGE_SIZE) > cprm->limit) ||
2033 !dump_write(cprm->file, kaddr,
2034 PAGE_SIZE);
2035 kunmap(page);
2036 page_cache_release(page);
2037 } else
2038 stop = !dump_seek(cprm->file, PAGE_SIZE);
2039 if (stop)
2040 goto end_coredump;
2041 }
2042 }
2043
2044 if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit))
2045 goto end_coredump;
2046
2047 if (e_phnum == PN_XNUM) {
2048 size += sizeof(*shdr4extnum);
2049 if (size > cprm->limit
2050 || !dump_write(cprm->file, shdr4extnum,
2051 sizeof(*shdr4extnum)))
2052 goto end_coredump;
2053 }
2054
2055 end_coredump:
2056 set_fs(fs);
2057
2058 cleanup:
2059 free_note_info(&info);
2060 kfree(shdr4extnum);
2061 kfree(phdr4note);
2062 kfree(elf);
2063 out:
2064 return has_dumped;
2065 }
2066
2067 #endif /* CONFIG_ELF_CORE */
2068
2069 static int __init init_elf_binfmt(void)
2070 {
2071 return register_binfmt(&elf_format);
2072 }
2073
2074 static void __exit exit_elf_binfmt(void)
2075 {
2076 /* Remove the COFF and ELF loaders. */
2077 unregister_binfmt(&elf_format);
2078 }
2079
2080 core_initcall(init_elf_binfmt);
2081 module_exit(exit_elf_binfmt);
2082 MODULE_LICENSE("GPL");
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