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Input: tca8418-keypad - switch to using managed resources
[GitHub/mt8127/android_kernel_alcatel_ttab.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/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/vmalloc.h>
31 #include <linux/security.h>
32 #include <linux/random.h>
33 #include <linux/elf.h>
34 #include <linux/utsname.h>
35 #include <linux/coredump.h>
36 #include <asm/uaccess.h>
37 #include <asm/param.h>
38 #include <asm/page.h>
39
40 #ifndef user_long_t
41 #define user_long_t long
42 #endif
43 #ifndef user_siginfo_t
44 #define user_siginfo_t siginfo_t
45 #endif
46
47 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs);
48 static int load_elf_library(struct file *);
49 static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *,
50 int, int, unsigned long);
51
52 /*
53 * If we don't support core dumping, then supply a NULL so we
54 * don't even try.
55 */
56 #ifdef CONFIG_ELF_CORE
57 static int elf_core_dump(struct coredump_params *cprm);
58 #else
59 #define elf_core_dump NULL
60 #endif
61
62 #if ELF_EXEC_PAGESIZE > PAGE_SIZE
63 #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
64 #else
65 #define ELF_MIN_ALIGN PAGE_SIZE
66 #endif
67
68 #ifndef ELF_CORE_EFLAGS
69 #define ELF_CORE_EFLAGS 0
70 #endif
71
72 #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
73 #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
74 #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
75
76 static struct linux_binfmt elf_format = {
77 .module = THIS_MODULE,
78 .load_binary = load_elf_binary,
79 .load_shlib = load_elf_library,
80 .core_dump = elf_core_dump,
81 .min_coredump = ELF_EXEC_PAGESIZE,
82 };
83
84 #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
85
86 static int set_brk(unsigned long start, unsigned long end)
87 {
88 start = ELF_PAGEALIGN(start);
89 end = ELF_PAGEALIGN(end);
90 if (end > start) {
91 unsigned long addr;
92 addr = vm_brk(start, end - start);
93 if (BAD_ADDR(addr))
94 return addr;
95 }
96 current->mm->start_brk = current->mm->brk = end;
97 return 0;
98 }
99
100 /* We need to explicitly zero any fractional pages
101 after the data section (i.e. bss). This would
102 contain the junk from the file that should not
103 be in memory
104 */
105 static int padzero(unsigned long elf_bss)
106 {
107 unsigned long nbyte;
108
109 nbyte = ELF_PAGEOFFSET(elf_bss);
110 if (nbyte) {
111 nbyte = ELF_MIN_ALIGN - nbyte;
112 if (clear_user((void __user *) elf_bss, nbyte))
113 return -EFAULT;
114 }
115 return 0;
116 }
117
118 /* Let's use some macros to make this stack manipulation a little clearer */
119 #ifdef CONFIG_STACK_GROWSUP
120 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
121 #define STACK_ROUND(sp, items) \
122 ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
123 #define STACK_ALLOC(sp, len) ({ \
124 elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
125 old_sp; })
126 #else
127 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
128 #define STACK_ROUND(sp, items) \
129 (((unsigned long) (sp - items)) &~ 15UL)
130 #define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
131 #endif
132
133 #ifndef ELF_BASE_PLATFORM
134 /*
135 * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
136 * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
137 * will be copied to the user stack in the same manner as AT_PLATFORM.
138 */
139 #define ELF_BASE_PLATFORM NULL
140 #endif
141
142 static int
143 create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
144 unsigned long load_addr, unsigned long interp_load_addr)
145 {
146 unsigned long p = bprm->p;
147 int argc = bprm->argc;
148 int envc = bprm->envc;
149 elf_addr_t __user *argv;
150 elf_addr_t __user *envp;
151 elf_addr_t __user *sp;
152 elf_addr_t __user *u_platform;
153 elf_addr_t __user *u_base_platform;
154 elf_addr_t __user *u_rand_bytes;
155 const char *k_platform = ELF_PLATFORM;
156 const char *k_base_platform = ELF_BASE_PLATFORM;
157 unsigned char k_rand_bytes[16];
158 int items;
159 elf_addr_t *elf_info;
160 int ei_index = 0;
161 const struct cred *cred = current_cred();
162 struct vm_area_struct *vma;
163
164 /*
165 * In some cases (e.g. Hyper-Threading), we want to avoid L1
166 * evictions by the processes running on the same package. One
167 * thing we can do is to shuffle the initial stack for them.
168 */
169
170 p = arch_align_stack(p);
171
172 /*
173 * If this architecture has a platform capability string, copy it
174 * to userspace. In some cases (Sparc), this info is impossible
175 * for userspace to get any other way, in others (i386) it is
176 * merely difficult.
177 */
178 u_platform = NULL;
179 if (k_platform) {
180 size_t len = strlen(k_platform) + 1;
181
182 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
183 if (__copy_to_user(u_platform, k_platform, len))
184 return -EFAULT;
185 }
186
187 /*
188 * If this architecture has a "base" platform capability
189 * string, copy it to userspace.
190 */
191 u_base_platform = NULL;
192 if (k_base_platform) {
193 size_t len = strlen(k_base_platform) + 1;
194
195 u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
196 if (__copy_to_user(u_base_platform, k_base_platform, len))
197 return -EFAULT;
198 }
199
200 /*
201 * Generate 16 random bytes for userspace PRNG seeding.
202 */
203 get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
204 u_rand_bytes = (elf_addr_t __user *)
205 STACK_ALLOC(p, sizeof(k_rand_bytes));
206 if (__copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes)))
207 return -EFAULT;
208
209 /* Create the ELF interpreter info */
210 elf_info = (elf_addr_t *)current->mm->saved_auxv;
211 /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
212 #define NEW_AUX_ENT(id, val) \
213 do { \
214 elf_info[ei_index++] = id; \
215 elf_info[ei_index++] = val; \
216 } while (0)
217
218 #ifdef ARCH_DLINFO
219 /*
220 * ARCH_DLINFO must come first so PPC can do its special alignment of
221 * AUXV.
222 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
223 * ARCH_DLINFO changes
224 */
225 ARCH_DLINFO;
226 #endif
227 NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
228 NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
229 NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
230 NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
231 NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
232 NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
233 NEW_AUX_ENT(AT_BASE, interp_load_addr);
234 NEW_AUX_ENT(AT_FLAGS, 0);
235 NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
236 NEW_AUX_ENT(AT_UID, from_kuid_munged(cred->user_ns, cred->uid));
237 NEW_AUX_ENT(AT_EUID, from_kuid_munged(cred->user_ns, cred->euid));
238 NEW_AUX_ENT(AT_GID, from_kgid_munged(cred->user_ns, cred->gid));
239 NEW_AUX_ENT(AT_EGID, from_kgid_munged(cred->user_ns, cred->egid));
240 NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
241 NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
242 NEW_AUX_ENT(AT_EXECFN, bprm->exec);
243 if (k_platform) {
244 NEW_AUX_ENT(AT_PLATFORM,
245 (elf_addr_t)(unsigned long)u_platform);
246 }
247 if (k_base_platform) {
248 NEW_AUX_ENT(AT_BASE_PLATFORM,
249 (elf_addr_t)(unsigned long)u_base_platform);
250 }
251 if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
252 NEW_AUX_ENT(AT_EXECFD, bprm->interp_data);
253 }
254 #undef NEW_AUX_ENT
255 /* AT_NULL is zero; clear the rest too */
256 memset(&elf_info[ei_index], 0,
257 sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
258
259 /* And advance past the AT_NULL entry. */
260 ei_index += 2;
261
262 sp = STACK_ADD(p, ei_index);
263
264 items = (argc + 1) + (envc + 1) + 1;
265 bprm->p = STACK_ROUND(sp, items);
266
267 /* Point sp at the lowest address on the stack */
268 #ifdef CONFIG_STACK_GROWSUP
269 sp = (elf_addr_t __user *)bprm->p - items - ei_index;
270 bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
271 #else
272 sp = (elf_addr_t __user *)bprm->p;
273 #endif
274
275
276 /*
277 * Grow the stack manually; some architectures have a limit on how
278 * far ahead a user-space access may be in order to grow the stack.
279 */
280 vma = find_extend_vma(current->mm, bprm->p);
281 if (!vma)
282 return -EFAULT;
283
284 /* Now, let's put argc (and argv, envp if appropriate) on the stack */
285 if (__put_user(argc, sp++))
286 return -EFAULT;
287 argv = sp;
288 envp = argv + argc + 1;
289
290 /* Populate argv and envp */
291 p = current->mm->arg_end = current->mm->arg_start;
292 while (argc-- > 0) {
293 size_t len;
294 if (__put_user((elf_addr_t)p, argv++))
295 return -EFAULT;
296 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
297 if (!len || len > MAX_ARG_STRLEN)
298 return -EINVAL;
299 p += len;
300 }
301 if (__put_user(0, argv))
302 return -EFAULT;
303 current->mm->arg_end = current->mm->env_start = p;
304 while (envc-- > 0) {
305 size_t len;
306 if (__put_user((elf_addr_t)p, envp++))
307 return -EFAULT;
308 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
309 if (!len || len > MAX_ARG_STRLEN)
310 return -EINVAL;
311 p += len;
312 }
313 if (__put_user(0, envp))
314 return -EFAULT;
315 current->mm->env_end = p;
316
317 /* Put the elf_info on the stack in the right place. */
318 sp = (elf_addr_t __user *)envp + 1;
319 if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
320 return -EFAULT;
321 return 0;
322 }
323
324 static unsigned long elf_map(struct file *filep, unsigned long addr,
325 struct elf_phdr *eppnt, int prot, int type,
326 unsigned long total_size)
327 {
328 unsigned long map_addr;
329 unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
330 unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
331 addr = ELF_PAGESTART(addr);
332 size = ELF_PAGEALIGN(size);
333
334 /* mmap() will return -EINVAL if given a zero size, but a
335 * segment with zero filesize is perfectly valid */
336 if (!size)
337 return addr;
338
339 /*
340 * total_size is the size of the ELF (interpreter) image.
341 * The _first_ mmap needs to know the full size, otherwise
342 * randomization might put this image into an overlapping
343 * position with the ELF binary image. (since size < total_size)
344 * So we first map the 'big' image - and unmap the remainder at
345 * the end. (which unmap is needed for ELF images with holes.)
346 */
347 if (total_size) {
348 total_size = ELF_PAGEALIGN(total_size);
349 map_addr = vm_mmap(filep, addr, total_size, prot, type, off);
350 if (!BAD_ADDR(map_addr))
351 vm_munmap(map_addr+size, total_size-size);
352 } else
353 map_addr = vm_mmap(filep, addr, size, prot, type, off);
354
355 return(map_addr);
356 }
357
358 static unsigned long total_mapping_size(struct elf_phdr *cmds, int nr)
359 {
360 int i, first_idx = -1, last_idx = -1;
361
362 for (i = 0; i < nr; i++) {
363 if (cmds[i].p_type == PT_LOAD) {
364 last_idx = i;
365 if (first_idx == -1)
366 first_idx = i;
367 }
368 }
369 if (first_idx == -1)
370 return 0;
371
372 return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz -
373 ELF_PAGESTART(cmds[first_idx].p_vaddr);
374 }
375
376
377 /* This is much more generalized than the library routine read function,
378 so we keep this separate. Technically the library read function
379 is only provided so that we can read a.out libraries that have
380 an ELF header */
381
382 static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
383 struct file *interpreter, unsigned long *interp_map_addr,
384 unsigned long no_base)
385 {
386 struct elf_phdr *elf_phdata;
387 struct elf_phdr *eppnt;
388 unsigned long load_addr = 0;
389 int load_addr_set = 0;
390 unsigned long last_bss = 0, elf_bss = 0;
391 unsigned long error = ~0UL;
392 unsigned long total_size;
393 int retval, i, size;
394
395 /* First of all, some simple consistency checks */
396 if (interp_elf_ex->e_type != ET_EXEC &&
397 interp_elf_ex->e_type != ET_DYN)
398 goto out;
399 if (!elf_check_arch(interp_elf_ex))
400 goto out;
401 if (!interpreter->f_op || !interpreter->f_op->mmap)
402 goto out;
403
404 /*
405 * If the size of this structure has changed, then punt, since
406 * we will be doing the wrong thing.
407 */
408 if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
409 goto out;
410 if (interp_elf_ex->e_phnum < 1 ||
411 interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
412 goto out;
413
414 /* Now read in all of the header information */
415 size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
416 if (size > ELF_MIN_ALIGN)
417 goto out;
418 elf_phdata = kmalloc(size, GFP_KERNEL);
419 if (!elf_phdata)
420 goto out;
421
422 retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
423 (char *)elf_phdata, size);
424 error = -EIO;
425 if (retval != size) {
426 if (retval < 0)
427 error = retval;
428 goto out_close;
429 }
430
431 total_size = total_mapping_size(elf_phdata, interp_elf_ex->e_phnum);
432 if (!total_size) {
433 error = -EINVAL;
434 goto out_close;
435 }
436
437 eppnt = elf_phdata;
438 for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
439 if (eppnt->p_type == PT_LOAD) {
440 int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
441 int elf_prot = 0;
442 unsigned long vaddr = 0;
443 unsigned long k, map_addr;
444
445 if (eppnt->p_flags & PF_R)
446 elf_prot = PROT_READ;
447 if (eppnt->p_flags & PF_W)
448 elf_prot |= PROT_WRITE;
449 if (eppnt->p_flags & PF_X)
450 elf_prot |= PROT_EXEC;
451 vaddr = eppnt->p_vaddr;
452 if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
453 elf_type |= MAP_FIXED;
454 else if (no_base && interp_elf_ex->e_type == ET_DYN)
455 load_addr = -vaddr;
456
457 map_addr = elf_map(interpreter, load_addr + vaddr,
458 eppnt, elf_prot, elf_type, total_size);
459 total_size = 0;
460 if (!*interp_map_addr)
461 *interp_map_addr = map_addr;
462 error = map_addr;
463 if (BAD_ADDR(map_addr))
464 goto out_close;
465
466 if (!load_addr_set &&
467 interp_elf_ex->e_type == ET_DYN) {
468 load_addr = map_addr - ELF_PAGESTART(vaddr);
469 load_addr_set = 1;
470 }
471
472 /*
473 * Check to see if the section's size will overflow the
474 * allowed task size. Note that p_filesz must always be
475 * <= p_memsize so it's only necessary to check p_memsz.
476 */
477 k = load_addr + eppnt->p_vaddr;
478 if (BAD_ADDR(k) ||
479 eppnt->p_filesz > eppnt->p_memsz ||
480 eppnt->p_memsz > TASK_SIZE ||
481 TASK_SIZE - eppnt->p_memsz < k) {
482 error = -ENOMEM;
483 goto out_close;
484 }
485
486 /*
487 * Find the end of the file mapping for this phdr, and
488 * keep track of the largest address we see for this.
489 */
490 k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
491 if (k > elf_bss)
492 elf_bss = k;
493
494 /*
495 * Do the same thing for the memory mapping - between
496 * elf_bss and last_bss is the bss section.
497 */
498 k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
499 if (k > last_bss)
500 last_bss = k;
501 }
502 }
503
504 if (last_bss > elf_bss) {
505 /*
506 * Now fill out the bss section. First pad the last page up
507 * to the page boundary, and then perform a mmap to make sure
508 * that there are zero-mapped pages up to and including the
509 * last bss page.
510 */
511 if (padzero(elf_bss)) {
512 error = -EFAULT;
513 goto out_close;
514 }
515
516 /* What we have mapped so far */
517 elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
518
519 /* Map the last of the bss segment */
520 error = vm_brk(elf_bss, last_bss - elf_bss);
521 if (BAD_ADDR(error))
522 goto out_close;
523 }
524
525 error = load_addr;
526
527 out_close:
528 kfree(elf_phdata);
529 out:
530 return error;
531 }
532
533 /*
534 * These are the functions used to load ELF style executables and shared
535 * libraries. There is no binary dependent code anywhere else.
536 */
537
538 #define INTERPRETER_NONE 0
539 #define INTERPRETER_ELF 2
540
541 #ifndef STACK_RND_MASK
542 #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
543 #endif
544
545 static unsigned long randomize_stack_top(unsigned long stack_top)
546 {
547 unsigned int random_variable = 0;
548
549 if ((current->flags & PF_RANDOMIZE) &&
550 !(current->personality & ADDR_NO_RANDOMIZE)) {
551 random_variable = get_random_int() & STACK_RND_MASK;
552 random_variable <<= PAGE_SHIFT;
553 }
554 #ifdef CONFIG_STACK_GROWSUP
555 return PAGE_ALIGN(stack_top) + random_variable;
556 #else
557 return PAGE_ALIGN(stack_top) - random_variable;
558 #endif
559 }
560
561 static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
562 {
563 struct file *interpreter = NULL; /* to shut gcc up */
564 unsigned long load_addr = 0, load_bias = 0;
565 int load_addr_set = 0;
566 char * elf_interpreter = NULL;
567 unsigned long error;
568 struct elf_phdr *elf_ppnt, *elf_phdata;
569 unsigned long elf_bss, elf_brk;
570 int retval, i;
571 unsigned int size;
572 unsigned long elf_entry;
573 unsigned long interp_load_addr = 0;
574 unsigned long start_code, end_code, start_data, end_data;
575 unsigned long reloc_func_desc __maybe_unused = 0;
576 int executable_stack = EXSTACK_DEFAULT;
577 unsigned long def_flags = 0;
578 struct {
579 struct elfhdr elf_ex;
580 struct elfhdr interp_elf_ex;
581 } *loc;
582
583 loc = kmalloc(sizeof(*loc), GFP_KERNEL);
584 if (!loc) {
585 retval = -ENOMEM;
586 goto out_ret;
587 }
588
589 /* Get the exec-header */
590 loc->elf_ex = *((struct elfhdr *)bprm->buf);
591
592 retval = -ENOEXEC;
593 /* First of all, some simple consistency checks */
594 if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
595 goto out;
596
597 if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
598 goto out;
599 if (!elf_check_arch(&loc->elf_ex))
600 goto out;
601 if (!bprm->file->f_op || !bprm->file->f_op->mmap)
602 goto out;
603
604 /* Now read in all of the header information */
605 if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr))
606 goto out;
607 if (loc->elf_ex.e_phnum < 1 ||
608 loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr))
609 goto out;
610 size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr);
611 retval = -ENOMEM;
612 elf_phdata = kmalloc(size, GFP_KERNEL);
613 if (!elf_phdata)
614 goto out;
615
616 retval = kernel_read(bprm->file, loc->elf_ex.e_phoff,
617 (char *)elf_phdata, size);
618 if (retval != size) {
619 if (retval >= 0)
620 retval = -EIO;
621 goto out_free_ph;
622 }
623
624 elf_ppnt = elf_phdata;
625 elf_bss = 0;
626 elf_brk = 0;
627
628 start_code = ~0UL;
629 end_code = 0;
630 start_data = 0;
631 end_data = 0;
632
633 for (i = 0; i < loc->elf_ex.e_phnum; i++) {
634 if (elf_ppnt->p_type == PT_INTERP) {
635 /* This is the program interpreter used for
636 * shared libraries - for now assume that this
637 * is an a.out format binary
638 */
639 retval = -ENOEXEC;
640 if (elf_ppnt->p_filesz > PATH_MAX ||
641 elf_ppnt->p_filesz < 2)
642 goto out_free_ph;
643
644 retval = -ENOMEM;
645 elf_interpreter = kmalloc(elf_ppnt->p_filesz,
646 GFP_KERNEL);
647 if (!elf_interpreter)
648 goto out_free_ph;
649
650 retval = kernel_read(bprm->file, elf_ppnt->p_offset,
651 elf_interpreter,
652 elf_ppnt->p_filesz);
653 if (retval != elf_ppnt->p_filesz) {
654 if (retval >= 0)
655 retval = -EIO;
656 goto out_free_interp;
657 }
658 /* make sure path is NULL terminated */
659 retval = -ENOEXEC;
660 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
661 goto out_free_interp;
662
663 interpreter = open_exec(elf_interpreter);
664 retval = PTR_ERR(interpreter);
665 if (IS_ERR(interpreter))
666 goto out_free_interp;
667
668 /*
669 * If the binary is not readable then enforce
670 * mm->dumpable = 0 regardless of the interpreter's
671 * permissions.
672 */
673 would_dump(bprm, interpreter);
674
675 retval = kernel_read(interpreter, 0, bprm->buf,
676 BINPRM_BUF_SIZE);
677 if (retval != BINPRM_BUF_SIZE) {
678 if (retval >= 0)
679 retval = -EIO;
680 goto out_free_dentry;
681 }
682
683 /* Get the exec headers */
684 loc->interp_elf_ex = *((struct elfhdr *)bprm->buf);
685 break;
686 }
687 elf_ppnt++;
688 }
689
690 elf_ppnt = elf_phdata;
691 for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
692 if (elf_ppnt->p_type == PT_GNU_STACK) {
693 if (elf_ppnt->p_flags & PF_X)
694 executable_stack = EXSTACK_ENABLE_X;
695 else
696 executable_stack = EXSTACK_DISABLE_X;
697 break;
698 }
699
700 /* Some simple consistency checks for the interpreter */
701 if (elf_interpreter) {
702 retval = -ELIBBAD;
703 /* Not an ELF interpreter */
704 if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
705 goto out_free_dentry;
706 /* Verify the interpreter has a valid arch */
707 if (!elf_check_arch(&loc->interp_elf_ex))
708 goto out_free_dentry;
709 }
710
711 /* Flush all traces of the currently running executable */
712 retval = flush_old_exec(bprm);
713 if (retval)
714 goto out_free_dentry;
715
716 /* OK, This is the point of no return */
717 current->mm->def_flags = def_flags;
718
719 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
720 may depend on the personality. */
721 SET_PERSONALITY(loc->elf_ex);
722 if (elf_read_implies_exec(loc->elf_ex, executable_stack))
723 current->personality |= READ_IMPLIES_EXEC;
724
725 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
726 current->flags |= PF_RANDOMIZE;
727
728 setup_new_exec(bprm);
729
730 /* Do this so that we can load the interpreter, if need be. We will
731 change some of these later */
732 current->mm->free_area_cache = current->mm->mmap_base;
733 current->mm->cached_hole_size = 0;
734 retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
735 executable_stack);
736 if (retval < 0) {
737 send_sig(SIGKILL, current, 0);
738 goto out_free_dentry;
739 }
740
741 current->mm->start_stack = bprm->p;
742
743 /* Now we do a little grungy work by mmapping the ELF image into
744 the correct location in memory. */
745 for(i = 0, elf_ppnt = elf_phdata;
746 i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
747 int elf_prot = 0, elf_flags;
748 unsigned long k, vaddr;
749
750 if (elf_ppnt->p_type != PT_LOAD)
751 continue;
752
753 if (unlikely (elf_brk > elf_bss)) {
754 unsigned long nbyte;
755
756 /* There was a PT_LOAD segment with p_memsz > p_filesz
757 before this one. Map anonymous pages, if needed,
758 and clear the area. */
759 retval = set_brk(elf_bss + load_bias,
760 elf_brk + load_bias);
761 if (retval) {
762 send_sig(SIGKILL, current, 0);
763 goto out_free_dentry;
764 }
765 nbyte = ELF_PAGEOFFSET(elf_bss);
766 if (nbyte) {
767 nbyte = ELF_MIN_ALIGN - nbyte;
768 if (nbyte > elf_brk - elf_bss)
769 nbyte = elf_brk - elf_bss;
770 if (clear_user((void __user *)elf_bss +
771 load_bias, nbyte)) {
772 /*
773 * This bss-zeroing can fail if the ELF
774 * file specifies odd protections. So
775 * we don't check the return value
776 */
777 }
778 }
779 }
780
781 if (elf_ppnt->p_flags & PF_R)
782 elf_prot |= PROT_READ;
783 if (elf_ppnt->p_flags & PF_W)
784 elf_prot |= PROT_WRITE;
785 if (elf_ppnt->p_flags & PF_X)
786 elf_prot |= PROT_EXEC;
787
788 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
789
790 vaddr = elf_ppnt->p_vaddr;
791 if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
792 elf_flags |= MAP_FIXED;
793 } else if (loc->elf_ex.e_type == ET_DYN) {
794 /* Try and get dynamic programs out of the way of the
795 * default mmap base, as well as whatever program they
796 * might try to exec. This is because the brk will
797 * follow the loader, and is not movable. */
798 #ifdef CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE
799 /* Memory randomization might have been switched off
800 * in runtime via sysctl.
801 * If that is the case, retain the original non-zero
802 * load_bias value in order to establish proper
803 * non-randomized mappings.
804 */
805 if (current->flags & PF_RANDOMIZE)
806 load_bias = 0;
807 else
808 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
809 #else
810 load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
811 #endif
812 }
813
814 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
815 elf_prot, elf_flags, 0);
816 if (BAD_ADDR(error)) {
817 send_sig(SIGKILL, current, 0);
818 retval = IS_ERR((void *)error) ?
819 PTR_ERR((void*)error) : -EINVAL;
820 goto out_free_dentry;
821 }
822
823 if (!load_addr_set) {
824 load_addr_set = 1;
825 load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
826 if (loc->elf_ex.e_type == ET_DYN) {
827 load_bias += error -
828 ELF_PAGESTART(load_bias + vaddr);
829 load_addr += load_bias;
830 reloc_func_desc = load_bias;
831 }
832 }
833 k = elf_ppnt->p_vaddr;
834 if (k < start_code)
835 start_code = k;
836 if (start_data < k)
837 start_data = k;
838
839 /*
840 * Check to see if the section's size will overflow the
841 * allowed task size. Note that p_filesz must always be
842 * <= p_memsz so it is only necessary to check p_memsz.
843 */
844 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
845 elf_ppnt->p_memsz > TASK_SIZE ||
846 TASK_SIZE - elf_ppnt->p_memsz < k) {
847 /* set_brk can never work. Avoid overflows. */
848 send_sig(SIGKILL, current, 0);
849 retval = -EINVAL;
850 goto out_free_dentry;
851 }
852
853 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
854
855 if (k > elf_bss)
856 elf_bss = k;
857 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
858 end_code = k;
859 if (end_data < k)
860 end_data = k;
861 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
862 if (k > elf_brk)
863 elf_brk = k;
864 }
865
866 loc->elf_ex.e_entry += load_bias;
867 elf_bss += load_bias;
868 elf_brk += load_bias;
869 start_code += load_bias;
870 end_code += load_bias;
871 start_data += load_bias;
872 end_data += load_bias;
873
874 /* Calling set_brk effectively mmaps the pages that we need
875 * for the bss and break sections. We must do this before
876 * mapping in the interpreter, to make sure it doesn't wind
877 * up getting placed where the bss needs to go.
878 */
879 retval = set_brk(elf_bss, elf_brk);
880 if (retval) {
881 send_sig(SIGKILL, current, 0);
882 goto out_free_dentry;
883 }
884 if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
885 send_sig(SIGSEGV, current, 0);
886 retval = -EFAULT; /* Nobody gets to see this, but.. */
887 goto out_free_dentry;
888 }
889
890 if (elf_interpreter) {
891 unsigned long interp_map_addr = 0;
892
893 elf_entry = load_elf_interp(&loc->interp_elf_ex,
894 interpreter,
895 &interp_map_addr,
896 load_bias);
897 if (!IS_ERR((void *)elf_entry)) {
898 /*
899 * load_elf_interp() returns relocation
900 * adjustment
901 */
902 interp_load_addr = elf_entry;
903 elf_entry += loc->interp_elf_ex.e_entry;
904 }
905 if (BAD_ADDR(elf_entry)) {
906 force_sig(SIGSEGV, current);
907 retval = IS_ERR((void *)elf_entry) ?
908 (int)elf_entry : -EINVAL;
909 goto out_free_dentry;
910 }
911 reloc_func_desc = interp_load_addr;
912
913 allow_write_access(interpreter);
914 fput(interpreter);
915 kfree(elf_interpreter);
916 } else {
917 elf_entry = loc->elf_ex.e_entry;
918 if (BAD_ADDR(elf_entry)) {
919 force_sig(SIGSEGV, current);
920 retval = -EINVAL;
921 goto out_free_dentry;
922 }
923 }
924
925 kfree(elf_phdata);
926
927 set_binfmt(&elf_format);
928
929 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
930 retval = arch_setup_additional_pages(bprm, !!elf_interpreter);
931 if (retval < 0) {
932 send_sig(SIGKILL, current, 0);
933 goto out;
934 }
935 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
936
937 install_exec_creds(bprm);
938 retval = create_elf_tables(bprm, &loc->elf_ex,
939 load_addr, interp_load_addr);
940 if (retval < 0) {
941 send_sig(SIGKILL, current, 0);
942 goto out;
943 }
944 /* N.B. passed_fileno might not be initialized? */
945 current->mm->end_code = end_code;
946 current->mm->start_code = start_code;
947 current->mm->start_data = start_data;
948 current->mm->end_data = end_data;
949 current->mm->start_stack = bprm->p;
950
951 #ifdef arch_randomize_brk
952 if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) {
953 current->mm->brk = current->mm->start_brk =
954 arch_randomize_brk(current->mm);
955 #ifdef CONFIG_COMPAT_BRK
956 current->brk_randomized = 1;
957 #endif
958 }
959 #endif
960
961 if (current->personality & MMAP_PAGE_ZERO) {
962 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
963 and some applications "depend" upon this behavior.
964 Since we do not have the power to recompile these, we
965 emulate the SVr4 behavior. Sigh. */
966 error = vm_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
967 MAP_FIXED | MAP_PRIVATE, 0);
968 }
969
970 #ifdef ELF_PLAT_INIT
971 /*
972 * The ABI may specify that certain registers be set up in special
973 * ways (on i386 %edx is the address of a DT_FINI function, for
974 * example. In addition, it may also specify (eg, PowerPC64 ELF)
975 * that the e_entry field is the address of the function descriptor
976 * for the startup routine, rather than the address of the startup
977 * routine itself. This macro performs whatever initialization to
978 * the regs structure is required as well as any relocations to the
979 * function descriptor entries when executing dynamically links apps.
980 */
981 ELF_PLAT_INIT(regs, reloc_func_desc);
982 #endif
983
984 start_thread(regs, elf_entry, bprm->p);
985 retval = 0;
986 out:
987 kfree(loc);
988 out_ret:
989 return retval;
990
991 /* error cleanup */
992 out_free_dentry:
993 allow_write_access(interpreter);
994 if (interpreter)
995 fput(interpreter);
996 out_free_interp:
997 kfree(elf_interpreter);
998 out_free_ph:
999 kfree(elf_phdata);
1000 goto out;
1001 }
1002
1003 /* This is really simpleminded and specialized - we are loading an
1004 a.out library that is given an ELF header. */
1005 static int load_elf_library(struct file *file)
1006 {
1007 struct elf_phdr *elf_phdata;
1008 struct elf_phdr *eppnt;
1009 unsigned long elf_bss, bss, len;
1010 int retval, error, i, j;
1011 struct elfhdr elf_ex;
1012
1013 error = -ENOEXEC;
1014 retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
1015 if (retval != sizeof(elf_ex))
1016 goto out;
1017
1018 if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
1019 goto out;
1020
1021 /* First of all, some simple consistency checks */
1022 if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
1023 !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
1024 goto out;
1025
1026 /* Now read in all of the header information */
1027
1028 j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
1029 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1030
1031 error = -ENOMEM;
1032 elf_phdata = kmalloc(j, GFP_KERNEL);
1033 if (!elf_phdata)
1034 goto out;
1035
1036 eppnt = elf_phdata;
1037 error = -ENOEXEC;
1038 retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
1039 if (retval != j)
1040 goto out_free_ph;
1041
1042 for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
1043 if ((eppnt + i)->p_type == PT_LOAD)
1044 j++;
1045 if (j != 1)
1046 goto out_free_ph;
1047
1048 while (eppnt->p_type != PT_LOAD)
1049 eppnt++;
1050
1051 /* Now use mmap to map the library into memory. */
1052 error = vm_mmap(file,
1053 ELF_PAGESTART(eppnt->p_vaddr),
1054 (eppnt->p_filesz +
1055 ELF_PAGEOFFSET(eppnt->p_vaddr)),
1056 PROT_READ | PROT_WRITE | PROT_EXEC,
1057 MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
1058 (eppnt->p_offset -
1059 ELF_PAGEOFFSET(eppnt->p_vaddr)));
1060 if (error != ELF_PAGESTART(eppnt->p_vaddr))
1061 goto out_free_ph;
1062
1063 elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
1064 if (padzero(elf_bss)) {
1065 error = -EFAULT;
1066 goto out_free_ph;
1067 }
1068
1069 len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
1070 ELF_MIN_ALIGN - 1);
1071 bss = eppnt->p_memsz + eppnt->p_vaddr;
1072 if (bss > len)
1073 vm_brk(len, bss - len);
1074 error = 0;
1075
1076 out_free_ph:
1077 kfree(elf_phdata);
1078 out:
1079 return error;
1080 }
1081
1082 #ifdef CONFIG_ELF_CORE
1083 /*
1084 * ELF core dumper
1085 *
1086 * Modelled on fs/exec.c:aout_core_dump()
1087 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1088 */
1089
1090 /*
1091 * The purpose of always_dump_vma() is to make sure that special kernel mappings
1092 * that are useful for post-mortem analysis are included in every core dump.
1093 * In that way we ensure that the core dump is fully interpretable later
1094 * without matching up the same kernel and hardware config to see what PC values
1095 * meant. These special mappings include - vDSO, vsyscall, and other
1096 * architecture specific mappings
1097 */
1098 static bool always_dump_vma(struct vm_area_struct *vma)
1099 {
1100 /* Any vsyscall mappings? */
1101 if (vma == get_gate_vma(vma->vm_mm))
1102 return true;
1103 /*
1104 * arch_vma_name() returns non-NULL for special architecture mappings,
1105 * such as vDSO sections.
1106 */
1107 if (arch_vma_name(vma))
1108 return true;
1109
1110 return false;
1111 }
1112
1113 /*
1114 * Decide what to dump of a segment, part, all or none.
1115 */
1116 static unsigned long vma_dump_size(struct vm_area_struct *vma,
1117 unsigned long mm_flags)
1118 {
1119 #define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1120
1121 /* always dump the vdso and vsyscall sections */
1122 if (always_dump_vma(vma))
1123 goto whole;
1124
1125 if (vma->vm_flags & VM_DONTDUMP)
1126 return 0;
1127
1128 /* Hugetlb memory check */
1129 if (vma->vm_flags & VM_HUGETLB) {
1130 if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
1131 goto whole;
1132 if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
1133 goto whole;
1134 }
1135
1136 /* Do not dump I/O mapped devices or special mappings */
1137 if (vma->vm_flags & VM_IO)
1138 return 0;
1139
1140 /* By default, dump shared memory if mapped from an anonymous file. */
1141 if (vma->vm_flags & VM_SHARED) {
1142 if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ?
1143 FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
1144 goto whole;
1145 return 0;
1146 }
1147
1148 /* Dump segments that have been written to. */
1149 if (vma->anon_vma && FILTER(ANON_PRIVATE))
1150 goto whole;
1151 if (vma->vm_file == NULL)
1152 return 0;
1153
1154 if (FILTER(MAPPED_PRIVATE))
1155 goto whole;
1156
1157 /*
1158 * If this looks like the beginning of a DSO or executable mapping,
1159 * check for an ELF header. If we find one, dump the first page to
1160 * aid in determining what was mapped here.
1161 */
1162 if (FILTER(ELF_HEADERS) &&
1163 vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
1164 u32 __user *header = (u32 __user *) vma->vm_start;
1165 u32 word;
1166 mm_segment_t fs = get_fs();
1167 /*
1168 * Doing it this way gets the constant folded by GCC.
1169 */
1170 union {
1171 u32 cmp;
1172 char elfmag[SELFMAG];
1173 } magic;
1174 BUILD_BUG_ON(SELFMAG != sizeof word);
1175 magic.elfmag[EI_MAG0] = ELFMAG0;
1176 magic.elfmag[EI_MAG1] = ELFMAG1;
1177 magic.elfmag[EI_MAG2] = ELFMAG2;
1178 magic.elfmag[EI_MAG3] = ELFMAG3;
1179 /*
1180 * Switch to the user "segment" for get_user(),
1181 * then put back what elf_core_dump() had in place.
1182 */
1183 set_fs(USER_DS);
1184 if (unlikely(get_user(word, header)))
1185 word = 0;
1186 set_fs(fs);
1187 if (word == magic.cmp)
1188 return PAGE_SIZE;
1189 }
1190
1191 #undef FILTER
1192
1193 return 0;
1194
1195 whole:
1196 return vma->vm_end - vma->vm_start;
1197 }
1198
1199 /* An ELF note in memory */
1200 struct memelfnote
1201 {
1202 const char *name;
1203 int type;
1204 unsigned int datasz;
1205 void *data;
1206 };
1207
1208 static int notesize(struct memelfnote *en)
1209 {
1210 int sz;
1211
1212 sz = sizeof(struct elf_note);
1213 sz += roundup(strlen(en->name) + 1, 4);
1214 sz += roundup(en->datasz, 4);
1215
1216 return sz;
1217 }
1218
1219 #define DUMP_WRITE(addr, nr, foffset) \
1220 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
1221
1222 static int alignfile(struct file *file, loff_t *foffset)
1223 {
1224 static const char buf[4] = { 0, };
1225 DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
1226 return 1;
1227 }
1228
1229 static int writenote(struct memelfnote *men, struct file *file,
1230 loff_t *foffset)
1231 {
1232 struct elf_note en;
1233 en.n_namesz = strlen(men->name) + 1;
1234 en.n_descsz = men->datasz;
1235 en.n_type = men->type;
1236
1237 DUMP_WRITE(&en, sizeof(en), foffset);
1238 DUMP_WRITE(men->name, en.n_namesz, foffset);
1239 if (!alignfile(file, foffset))
1240 return 0;
1241 DUMP_WRITE(men->data, men->datasz, foffset);
1242 if (!alignfile(file, foffset))
1243 return 0;
1244
1245 return 1;
1246 }
1247 #undef DUMP_WRITE
1248
1249 static void fill_elf_header(struct elfhdr *elf, int segs,
1250 u16 machine, u32 flags, u8 osabi)
1251 {
1252 memset(elf, 0, sizeof(*elf));
1253
1254 memcpy(elf->e_ident, ELFMAG, SELFMAG);
1255 elf->e_ident[EI_CLASS] = ELF_CLASS;
1256 elf->e_ident[EI_DATA] = ELF_DATA;
1257 elf->e_ident[EI_VERSION] = EV_CURRENT;
1258 elf->e_ident[EI_OSABI] = ELF_OSABI;
1259
1260 elf->e_type = ET_CORE;
1261 elf->e_machine = machine;
1262 elf->e_version = EV_CURRENT;
1263 elf->e_phoff = sizeof(struct elfhdr);
1264 elf->e_flags = flags;
1265 elf->e_ehsize = sizeof(struct elfhdr);
1266 elf->e_phentsize = sizeof(struct elf_phdr);
1267 elf->e_phnum = segs;
1268
1269 return;
1270 }
1271
1272 static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
1273 {
1274 phdr->p_type = PT_NOTE;
1275 phdr->p_offset = offset;
1276 phdr->p_vaddr = 0;
1277 phdr->p_paddr = 0;
1278 phdr->p_filesz = sz;
1279 phdr->p_memsz = 0;
1280 phdr->p_flags = 0;
1281 phdr->p_align = 0;
1282 return;
1283 }
1284
1285 static void fill_note(struct memelfnote *note, const char *name, int type,
1286 unsigned int sz, void *data)
1287 {
1288 note->name = name;
1289 note->type = type;
1290 note->datasz = sz;
1291 note->data = data;
1292 return;
1293 }
1294
1295 /*
1296 * fill up all the fields in prstatus from the given task struct, except
1297 * registers which need to be filled up separately.
1298 */
1299 static void fill_prstatus(struct elf_prstatus *prstatus,
1300 struct task_struct *p, long signr)
1301 {
1302 prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
1303 prstatus->pr_sigpend = p->pending.signal.sig[0];
1304 prstatus->pr_sighold = p->blocked.sig[0];
1305 rcu_read_lock();
1306 prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1307 rcu_read_unlock();
1308 prstatus->pr_pid = task_pid_vnr(p);
1309 prstatus->pr_pgrp = task_pgrp_vnr(p);
1310 prstatus->pr_sid = task_session_vnr(p);
1311 if (thread_group_leader(p)) {
1312 struct task_cputime cputime;
1313
1314 /*
1315 * This is the record for the group leader. It shows the
1316 * group-wide total, not its individual thread total.
1317 */
1318 thread_group_cputime(p, &cputime);
1319 cputime_to_timeval(cputime.utime, &prstatus->pr_utime);
1320 cputime_to_timeval(cputime.stime, &prstatus->pr_stime);
1321 } else {
1322 cputime_to_timeval(p->utime, &prstatus->pr_utime);
1323 cputime_to_timeval(p->stime, &prstatus->pr_stime);
1324 }
1325 cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
1326 cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
1327 }
1328
1329 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
1330 struct mm_struct *mm)
1331 {
1332 const struct cred *cred;
1333 unsigned int i, len;
1334
1335 /* first copy the parameters from user space */
1336 memset(psinfo, 0, sizeof(struct elf_prpsinfo));
1337
1338 len = mm->arg_end - mm->arg_start;
1339 if (len >= ELF_PRARGSZ)
1340 len = ELF_PRARGSZ-1;
1341 if (copy_from_user(&psinfo->pr_psargs,
1342 (const char __user *)mm->arg_start, len))
1343 return -EFAULT;
1344 for(i = 0; i < len; i++)
1345 if (psinfo->pr_psargs[i] == 0)
1346 psinfo->pr_psargs[i] = ' ';
1347 psinfo->pr_psargs[len] = 0;
1348
1349 rcu_read_lock();
1350 psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
1351 rcu_read_unlock();
1352 psinfo->pr_pid = task_pid_vnr(p);
1353 psinfo->pr_pgrp = task_pgrp_vnr(p);
1354 psinfo->pr_sid = task_session_vnr(p);
1355
1356 i = p->state ? ffz(~p->state) + 1 : 0;
1357 psinfo->pr_state = i;
1358 psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
1359 psinfo->pr_zomb = psinfo->pr_sname == 'Z';
1360 psinfo->pr_nice = task_nice(p);
1361 psinfo->pr_flag = p->flags;
1362 rcu_read_lock();
1363 cred = __task_cred(p);
1364 SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid));
1365 SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid));
1366 rcu_read_unlock();
1367 strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
1368
1369 return 0;
1370 }
1371
1372 static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
1373 {
1374 elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
1375 int i = 0;
1376 do
1377 i += 2;
1378 while (auxv[i - 2] != AT_NULL);
1379 fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
1380 }
1381
1382 static void fill_siginfo_note(struct memelfnote *note, user_siginfo_t *csigdata,
1383 siginfo_t *siginfo)
1384 {
1385 mm_segment_t old_fs = get_fs();
1386 set_fs(KERNEL_DS);
1387 copy_siginfo_to_user((user_siginfo_t __user *) csigdata, siginfo);
1388 set_fs(old_fs);
1389 fill_note(note, "CORE", NT_SIGINFO, sizeof(*csigdata), csigdata);
1390 }
1391
1392 #define MAX_FILE_NOTE_SIZE (4*1024*1024)
1393 /*
1394 * Format of NT_FILE note:
1395 *
1396 * long count -- how many files are mapped
1397 * long page_size -- units for file_ofs
1398 * array of [COUNT] elements of
1399 * long start
1400 * long end
1401 * long file_ofs
1402 * followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL...
1403 */
1404 static void fill_files_note(struct memelfnote *note)
1405 {
1406 struct vm_area_struct *vma;
1407 unsigned count, size, names_ofs, remaining, n;
1408 user_long_t *data;
1409 user_long_t *start_end_ofs;
1410 char *name_base, *name_curpos;
1411
1412 /* *Estimated* file count and total data size needed */
1413 count = current->mm->map_count;
1414 size = count * 64;
1415
1416 names_ofs = (2 + 3 * count) * sizeof(data[0]);
1417 alloc:
1418 if (size >= MAX_FILE_NOTE_SIZE) /* paranoia check */
1419 goto err;
1420 size = round_up(size, PAGE_SIZE);
1421 data = vmalloc(size);
1422 if (!data)
1423 goto err;
1424
1425 start_end_ofs = data + 2;
1426 name_base = name_curpos = ((char *)data) + names_ofs;
1427 remaining = size - names_ofs;
1428 count = 0;
1429 for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
1430 struct file *file;
1431 const char *filename;
1432
1433 file = vma->vm_file;
1434 if (!file)
1435 continue;
1436 filename = d_path(&file->f_path, name_curpos, remaining);
1437 if (IS_ERR(filename)) {
1438 if (PTR_ERR(filename) == -ENAMETOOLONG) {
1439 vfree(data);
1440 size = size * 5 / 4;
1441 goto alloc;
1442 }
1443 continue;
1444 }
1445
1446 /* d_path() fills at the end, move name down */
1447 /* n = strlen(filename) + 1: */
1448 n = (name_curpos + remaining) - filename;
1449 remaining = filename - name_curpos;
1450 memmove(name_curpos, filename, n);
1451 name_curpos += n;
1452
1453 *start_end_ofs++ = vma->vm_start;
1454 *start_end_ofs++ = vma->vm_end;
1455 *start_end_ofs++ = vma->vm_pgoff;
1456 count++;
1457 }
1458
1459 /* Now we know exact count of files, can store it */
1460 data[0] = count;
1461 data[1] = PAGE_SIZE;
1462 /*
1463 * Count usually is less than current->mm->map_count,
1464 * we need to move filenames down.
1465 */
1466 n = current->mm->map_count - count;
1467 if (n != 0) {
1468 unsigned shift_bytes = n * 3 * sizeof(data[0]);
1469 memmove(name_base - shift_bytes, name_base,
1470 name_curpos - name_base);
1471 name_curpos -= shift_bytes;
1472 }
1473
1474 size = name_curpos - (char *)data;
1475 fill_note(note, "CORE", NT_FILE, size, data);
1476 err: ;
1477 }
1478
1479 #ifdef CORE_DUMP_USE_REGSET
1480 #include <linux/regset.h>
1481
1482 struct elf_thread_core_info {
1483 struct elf_thread_core_info *next;
1484 struct task_struct *task;
1485 struct elf_prstatus prstatus;
1486 struct memelfnote notes[0];
1487 };
1488
1489 struct elf_note_info {
1490 struct elf_thread_core_info *thread;
1491 struct memelfnote psinfo;
1492 struct memelfnote signote;
1493 struct memelfnote auxv;
1494 struct memelfnote files;
1495 user_siginfo_t csigdata;
1496 size_t size;
1497 int thread_notes;
1498 };
1499
1500 /*
1501 * When a regset has a writeback hook, we call it on each thread before
1502 * dumping user memory. On register window machines, this makes sure the
1503 * user memory backing the register data is up to date before we read it.
1504 */
1505 static void do_thread_regset_writeback(struct task_struct *task,
1506 const struct user_regset *regset)
1507 {
1508 if (regset->writeback)
1509 regset->writeback(task, regset, 1);
1510 }
1511
1512 #ifndef PR_REG_SIZE
1513 #define PR_REG_SIZE(S) sizeof(S)
1514 #endif
1515
1516 #ifndef PRSTATUS_SIZE
1517 #define PRSTATUS_SIZE(S) sizeof(S)
1518 #endif
1519
1520 #ifndef PR_REG_PTR
1521 #define PR_REG_PTR(S) (&((S)->pr_reg))
1522 #endif
1523
1524 #ifndef SET_PR_FPVALID
1525 #define SET_PR_FPVALID(S, V) ((S)->pr_fpvalid = (V))
1526 #endif
1527
1528 static int fill_thread_core_info(struct elf_thread_core_info *t,
1529 const struct user_regset_view *view,
1530 long signr, size_t *total)
1531 {
1532 unsigned int i;
1533
1534 /*
1535 * NT_PRSTATUS is the one special case, because the regset data
1536 * goes into the pr_reg field inside the note contents, rather
1537 * than being the whole note contents. We fill the reset in here.
1538 * We assume that regset 0 is NT_PRSTATUS.
1539 */
1540 fill_prstatus(&t->prstatus, t->task, signr);
1541 (void) view->regsets[0].get(t->task, &view->regsets[0],
1542 0, PR_REG_SIZE(t->prstatus.pr_reg),
1543 PR_REG_PTR(&t->prstatus), NULL);
1544
1545 fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
1546 PRSTATUS_SIZE(t->prstatus), &t->prstatus);
1547 *total += notesize(&t->notes[0]);
1548
1549 do_thread_regset_writeback(t->task, &view->regsets[0]);
1550
1551 /*
1552 * Each other regset might generate a note too. For each regset
1553 * that has no core_note_type or is inactive, we leave t->notes[i]
1554 * all zero and we'll know to skip writing it later.
1555 */
1556 for (i = 1; i < view->n; ++i) {
1557 const struct user_regset *regset = &view->regsets[i];
1558 do_thread_regset_writeback(t->task, regset);
1559 if (regset->core_note_type && regset->get &&
1560 (!regset->active || regset->active(t->task, regset))) {
1561 int ret;
1562 size_t size = regset->n * regset->size;
1563 void *data = kmalloc(size, GFP_KERNEL);
1564 if (unlikely(!data))
1565 return 0;
1566 ret = regset->get(t->task, regset,
1567 0, size, data, NULL);
1568 if (unlikely(ret))
1569 kfree(data);
1570 else {
1571 if (regset->core_note_type != NT_PRFPREG)
1572 fill_note(&t->notes[i], "LINUX",
1573 regset->core_note_type,
1574 size, data);
1575 else {
1576 SET_PR_FPVALID(&t->prstatus, 1);
1577 fill_note(&t->notes[i], "CORE",
1578 NT_PRFPREG, size, data);
1579 }
1580 *total += notesize(&t->notes[i]);
1581 }
1582 }
1583 }
1584
1585 return 1;
1586 }
1587
1588 static int fill_note_info(struct elfhdr *elf, int phdrs,
1589 struct elf_note_info *info,
1590 siginfo_t *siginfo, struct pt_regs *regs)
1591 {
1592 struct task_struct *dump_task = current;
1593 const struct user_regset_view *view = task_user_regset_view(dump_task);
1594 struct elf_thread_core_info *t;
1595 struct elf_prpsinfo *psinfo;
1596 struct core_thread *ct;
1597 unsigned int i;
1598
1599 info->size = 0;
1600 info->thread = NULL;
1601
1602 psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
1603 if (psinfo == NULL)
1604 return 0;
1605
1606 fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
1607
1608 /*
1609 * Figure out how many notes we're going to need for each thread.
1610 */
1611 info->thread_notes = 0;
1612 for (i = 0; i < view->n; ++i)
1613 if (view->regsets[i].core_note_type != 0)
1614 ++info->thread_notes;
1615
1616 /*
1617 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1618 * since it is our one special case.
1619 */
1620 if (unlikely(info->thread_notes == 0) ||
1621 unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
1622 WARN_ON(1);
1623 return 0;
1624 }
1625
1626 /*
1627 * Initialize the ELF file header.
1628 */
1629 fill_elf_header(elf, phdrs,
1630 view->e_machine, view->e_flags, view->ei_osabi);
1631
1632 /*
1633 * Allocate a structure for each thread.
1634 */
1635 for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) {
1636 t = kzalloc(offsetof(struct elf_thread_core_info,
1637 notes[info->thread_notes]),
1638 GFP_KERNEL);
1639 if (unlikely(!t))
1640 return 0;
1641
1642 t->task = ct->task;
1643 if (ct->task == dump_task || !info->thread) {
1644 t->next = info->thread;
1645 info->thread = t;
1646 } else {
1647 /*
1648 * Make sure to keep the original task at
1649 * the head of the list.
1650 */
1651 t->next = info->thread->next;
1652 info->thread->next = t;
1653 }
1654 }
1655
1656 /*
1657 * Now fill in each thread's information.
1658 */
1659 for (t = info->thread; t != NULL; t = t->next)
1660 if (!fill_thread_core_info(t, view, siginfo->si_signo, &info->size))
1661 return 0;
1662
1663 /*
1664 * Fill in the two process-wide notes.
1665 */
1666 fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
1667 info->size += notesize(&info->psinfo);
1668
1669 fill_siginfo_note(&info->signote, &info->csigdata, siginfo);
1670 info->size += notesize(&info->signote);
1671
1672 fill_auxv_note(&info->auxv, current->mm);
1673 info->size += notesize(&info->auxv);
1674
1675 fill_files_note(&info->files);
1676 info->size += notesize(&info->files);
1677
1678 return 1;
1679 }
1680
1681 static size_t get_note_info_size(struct elf_note_info *info)
1682 {
1683 return info->size;
1684 }
1685
1686 /*
1687 * Write all the notes for each thread. When writing the first thread, the
1688 * process-wide notes are interleaved after the first thread-specific note.
1689 */
1690 static int write_note_info(struct elf_note_info *info,
1691 struct file *file, loff_t *foffset)
1692 {
1693 bool first = 1;
1694 struct elf_thread_core_info *t = info->thread;
1695
1696 do {
1697 int i;
1698
1699 if (!writenote(&t->notes[0], file, foffset))
1700 return 0;
1701
1702 if (first && !writenote(&info->psinfo, file, foffset))
1703 return 0;
1704 if (first && !writenote(&info->signote, file, foffset))
1705 return 0;
1706 if (first && !writenote(&info->auxv, file, foffset))
1707 return 0;
1708 if (first && !writenote(&info->files, file, foffset))
1709 return 0;
1710
1711 for (i = 1; i < info->thread_notes; ++i)
1712 if (t->notes[i].data &&
1713 !writenote(&t->notes[i], file, foffset))
1714 return 0;
1715
1716 first = 0;
1717 t = t->next;
1718 } while (t);
1719
1720 return 1;
1721 }
1722
1723 static void free_note_info(struct elf_note_info *info)
1724 {
1725 struct elf_thread_core_info *threads = info->thread;
1726 while (threads) {
1727 unsigned int i;
1728 struct elf_thread_core_info *t = threads;
1729 threads = t->next;
1730 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
1731 for (i = 1; i < info->thread_notes; ++i)
1732 kfree(t->notes[i].data);
1733 kfree(t);
1734 }
1735 kfree(info->psinfo.data);
1736 vfree(info->files.data);
1737 }
1738
1739 #else
1740
1741 /* Here is the structure in which status of each thread is captured. */
1742 struct elf_thread_status
1743 {
1744 struct list_head list;
1745 struct elf_prstatus prstatus; /* NT_PRSTATUS */
1746 elf_fpregset_t fpu; /* NT_PRFPREG */
1747 struct task_struct *thread;
1748 #ifdef ELF_CORE_COPY_XFPREGS
1749 elf_fpxregset_t xfpu; /* ELF_CORE_XFPREG_TYPE */
1750 #endif
1751 struct memelfnote notes[3];
1752 int num_notes;
1753 };
1754
1755 /*
1756 * In order to add the specific thread information for the elf file format,
1757 * we need to keep a linked list of every threads pr_status and then create
1758 * a single section for them in the final core file.
1759 */
1760 static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
1761 {
1762 int sz = 0;
1763 struct task_struct *p = t->thread;
1764 t->num_notes = 0;
1765
1766 fill_prstatus(&t->prstatus, p, signr);
1767 elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
1768
1769 fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
1770 &(t->prstatus));
1771 t->num_notes++;
1772 sz += notesize(&t->notes[0]);
1773
1774 if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
1775 &t->fpu))) {
1776 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
1777 &(t->fpu));
1778 t->num_notes++;
1779 sz += notesize(&t->notes[1]);
1780 }
1781
1782 #ifdef ELF_CORE_COPY_XFPREGS
1783 if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
1784 fill_note(&t->notes[2], "LINUX", ELF_CORE_XFPREG_TYPE,
1785 sizeof(t->xfpu), &t->xfpu);
1786 t->num_notes++;
1787 sz += notesize(&t->notes[2]);
1788 }
1789 #endif
1790 return sz;
1791 }
1792
1793 struct elf_note_info {
1794 struct memelfnote *notes;
1795 struct elf_prstatus *prstatus; /* NT_PRSTATUS */
1796 struct elf_prpsinfo *psinfo; /* NT_PRPSINFO */
1797 struct list_head thread_list;
1798 elf_fpregset_t *fpu;
1799 #ifdef ELF_CORE_COPY_XFPREGS
1800 elf_fpxregset_t *xfpu;
1801 #endif
1802 user_siginfo_t csigdata;
1803 int thread_status_size;
1804 int numnote;
1805 };
1806
1807 static int elf_note_info_init(struct elf_note_info *info)
1808 {
1809 memset(info, 0, sizeof(*info));
1810 INIT_LIST_HEAD(&info->thread_list);
1811
1812 /* Allocate space for ELF notes */
1813 info->notes = kmalloc(8 * sizeof(struct memelfnote), GFP_KERNEL);
1814 if (!info->notes)
1815 return 0;
1816 info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
1817 if (!info->psinfo)
1818 return 0;
1819 info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
1820 if (!info->prstatus)
1821 return 0;
1822 info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
1823 if (!info->fpu)
1824 return 0;
1825 #ifdef ELF_CORE_COPY_XFPREGS
1826 info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
1827 if (!info->xfpu)
1828 return 0;
1829 #endif
1830 return 1;
1831 }
1832
1833 static int fill_note_info(struct elfhdr *elf, int phdrs,
1834 struct elf_note_info *info,
1835 siginfo_t *siginfo, struct pt_regs *regs)
1836 {
1837 struct list_head *t;
1838
1839 if (!elf_note_info_init(info))
1840 return 0;
1841
1842 if (siginfo->si_signo) {
1843 struct core_thread *ct;
1844 struct elf_thread_status *ets;
1845
1846 for (ct = current->mm->core_state->dumper.next;
1847 ct; ct = ct->next) {
1848 ets = kzalloc(sizeof(*ets), GFP_KERNEL);
1849 if (!ets)
1850 return 0;
1851
1852 ets->thread = ct->task;
1853 list_add(&ets->list, &info->thread_list);
1854 }
1855
1856 list_for_each(t, &info->thread_list) {
1857 int sz;
1858
1859 ets = list_entry(t, struct elf_thread_status, list);
1860 sz = elf_dump_thread_status(siginfo->si_signo, ets);
1861 info->thread_status_size += sz;
1862 }
1863 }
1864 /* now collect the dump for the current */
1865 memset(info->prstatus, 0, sizeof(*info->prstatus));
1866 fill_prstatus(info->prstatus, current, siginfo->si_signo);
1867 elf_core_copy_regs(&info->prstatus->pr_reg, regs);
1868
1869 /* Set up header */
1870 fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS, ELF_OSABI);
1871
1872 /*
1873 * Set up the notes in similar form to SVR4 core dumps made
1874 * with info from their /proc.
1875 */
1876
1877 fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
1878 sizeof(*info->prstatus), info->prstatus);
1879 fill_psinfo(info->psinfo, current->group_leader, current->mm);
1880 fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
1881 sizeof(*info->psinfo), info->psinfo);
1882
1883 fill_siginfo_note(info->notes + 2, &info->csigdata, siginfo);
1884 fill_auxv_note(info->notes + 3, current->mm);
1885 fill_files_note(info->notes + 4);
1886
1887 info->numnote = 5;
1888
1889 /* Try to dump the FPU. */
1890 info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
1891 info->fpu);
1892 if (info->prstatus->pr_fpvalid)
1893 fill_note(info->notes + info->numnote++,
1894 "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
1895 #ifdef ELF_CORE_COPY_XFPREGS
1896 if (elf_core_copy_task_xfpregs(current, info->xfpu))
1897 fill_note(info->notes + info->numnote++,
1898 "LINUX", ELF_CORE_XFPREG_TYPE,
1899 sizeof(*info->xfpu), info->xfpu);
1900 #endif
1901
1902 return 1;
1903 }
1904
1905 static size_t get_note_info_size(struct elf_note_info *info)
1906 {
1907 int sz = 0;
1908 int i;
1909
1910 for (i = 0; i < info->numnote; i++)
1911 sz += notesize(info->notes + i);
1912
1913 sz += info->thread_status_size;
1914
1915 return sz;
1916 }
1917
1918 static int write_note_info(struct elf_note_info *info,
1919 struct file *file, loff_t *foffset)
1920 {
1921 int i;
1922 struct list_head *t;
1923
1924 for (i = 0; i < info->numnote; i++)
1925 if (!writenote(info->notes + i, file, foffset))
1926 return 0;
1927
1928 /* write out the thread status notes section */
1929 list_for_each(t, &info->thread_list) {
1930 struct elf_thread_status *tmp =
1931 list_entry(t, struct elf_thread_status, list);
1932
1933 for (i = 0; i < tmp->num_notes; i++)
1934 if (!writenote(&tmp->notes[i], file, foffset))
1935 return 0;
1936 }
1937
1938 return 1;
1939 }
1940
1941 static void free_note_info(struct elf_note_info *info)
1942 {
1943 while (!list_empty(&info->thread_list)) {
1944 struct list_head *tmp = info->thread_list.next;
1945 list_del(tmp);
1946 kfree(list_entry(tmp, struct elf_thread_status, list));
1947 }
1948
1949 /* Free data allocated by fill_files_note(): */
1950 vfree(info->notes[4].data);
1951
1952 kfree(info->prstatus);
1953 kfree(info->psinfo);
1954 kfree(info->notes);
1955 kfree(info->fpu);
1956 #ifdef ELF_CORE_COPY_XFPREGS
1957 kfree(info->xfpu);
1958 #endif
1959 }
1960
1961 #endif
1962
1963 static struct vm_area_struct *first_vma(struct task_struct *tsk,
1964 struct vm_area_struct *gate_vma)
1965 {
1966 struct vm_area_struct *ret = tsk->mm->mmap;
1967
1968 if (ret)
1969 return ret;
1970 return gate_vma;
1971 }
1972 /*
1973 * Helper function for iterating across a vma list. It ensures that the caller
1974 * will visit `gate_vma' prior to terminating the search.
1975 */
1976 static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma,
1977 struct vm_area_struct *gate_vma)
1978 {
1979 struct vm_area_struct *ret;
1980
1981 ret = this_vma->vm_next;
1982 if (ret)
1983 return ret;
1984 if (this_vma == gate_vma)
1985 return NULL;
1986 return gate_vma;
1987 }
1988
1989 static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
1990 elf_addr_t e_shoff, int segs)
1991 {
1992 elf->e_shoff = e_shoff;
1993 elf->e_shentsize = sizeof(*shdr4extnum);
1994 elf->e_shnum = 1;
1995 elf->e_shstrndx = SHN_UNDEF;
1996
1997 memset(shdr4extnum, 0, sizeof(*shdr4extnum));
1998
1999 shdr4extnum->sh_type = SHT_NULL;
2000 shdr4extnum->sh_size = elf->e_shnum;
2001 shdr4extnum->sh_link = elf->e_shstrndx;
2002 shdr4extnum->sh_info = segs;
2003 }
2004
2005 static size_t elf_core_vma_data_size(struct vm_area_struct *gate_vma,
2006 unsigned long mm_flags)
2007 {
2008 struct vm_area_struct *vma;
2009 size_t size = 0;
2010
2011 for (vma = first_vma(current, gate_vma); vma != NULL;
2012 vma = next_vma(vma, gate_vma))
2013 size += vma_dump_size(vma, mm_flags);
2014 return size;
2015 }
2016
2017 /*
2018 * Actual dumper
2019 *
2020 * This is a two-pass process; first we find the offsets of the bits,
2021 * and then they are actually written out. If we run out of core limit
2022 * we just truncate.
2023 */
2024 static int elf_core_dump(struct coredump_params *cprm)
2025 {
2026 int has_dumped = 0;
2027 mm_segment_t fs;
2028 int segs;
2029 size_t size = 0;
2030 struct vm_area_struct *vma, *gate_vma;
2031 struct elfhdr *elf = NULL;
2032 loff_t offset = 0, dataoff, foffset;
2033 struct elf_note_info info;
2034 struct elf_phdr *phdr4note = NULL;
2035 struct elf_shdr *shdr4extnum = NULL;
2036 Elf_Half e_phnum;
2037 elf_addr_t e_shoff;
2038
2039 /*
2040 * We no longer stop all VM operations.
2041 *
2042 * This is because those proceses that could possibly change map_count
2043 * or the mmap / vma pages are now blocked in do_exit on current
2044 * finishing this core dump.
2045 *
2046 * Only ptrace can touch these memory addresses, but it doesn't change
2047 * the map_count or the pages allocated. So no possibility of crashing
2048 * exists while dumping the mm->vm_next areas to the core file.
2049 */
2050
2051 /* alloc memory for large data structures: too large to be on stack */
2052 elf = kmalloc(sizeof(*elf), GFP_KERNEL);
2053 if (!elf)
2054 goto out;
2055 /*
2056 * The number of segs are recored into ELF header as 16bit value.
2057 * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
2058 */
2059 segs = current->mm->map_count;
2060 segs += elf_core_extra_phdrs();
2061
2062 gate_vma = get_gate_vma(current->mm);
2063 if (gate_vma != NULL)
2064 segs++;
2065
2066 /* for notes section */
2067 segs++;
2068
2069 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
2070 * this, kernel supports extended numbering. Have a look at
2071 * include/linux/elf.h for further information. */
2072 e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
2073
2074 /*
2075 * Collect all the non-memory information about the process for the
2076 * notes. This also sets up the file header.
2077 */
2078 if (!fill_note_info(elf, e_phnum, &info, cprm->siginfo, cprm->regs))
2079 goto cleanup;
2080
2081 has_dumped = 1;
2082 current->flags |= PF_DUMPCORE;
2083
2084 fs = get_fs();
2085 set_fs(KERNEL_DS);
2086
2087 offset += sizeof(*elf); /* Elf header */
2088 offset += segs * sizeof(struct elf_phdr); /* Program headers */
2089 foffset = offset;
2090
2091 /* Write notes phdr entry */
2092 {
2093 size_t sz = get_note_info_size(&info);
2094
2095 sz += elf_coredump_extra_notes_size();
2096
2097 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
2098 if (!phdr4note)
2099 goto end_coredump;
2100
2101 fill_elf_note_phdr(phdr4note, sz, offset);
2102 offset += sz;
2103 }
2104
2105 dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
2106
2107 offset += elf_core_vma_data_size(gate_vma, cprm->mm_flags);
2108 offset += elf_core_extra_data_size();
2109 e_shoff = offset;
2110
2111 if (e_phnum == PN_XNUM) {
2112 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
2113 if (!shdr4extnum)
2114 goto end_coredump;
2115 fill_extnum_info(elf, shdr4extnum, e_shoff, segs);
2116 }
2117
2118 offset = dataoff;
2119
2120 size += sizeof(*elf);
2121 if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
2122 goto end_coredump;
2123
2124 size += sizeof(*phdr4note);
2125 if (size > cprm->limit
2126 || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note)))
2127 goto end_coredump;
2128
2129 /* Write program headers for segments dump */
2130 for (vma = first_vma(current, gate_vma); vma != NULL;
2131 vma = next_vma(vma, gate_vma)) {
2132 struct elf_phdr phdr;
2133
2134 phdr.p_type = PT_LOAD;
2135 phdr.p_offset = offset;
2136 phdr.p_vaddr = vma->vm_start;
2137 phdr.p_paddr = 0;
2138 phdr.p_filesz = vma_dump_size(vma, cprm->mm_flags);
2139 phdr.p_memsz = vma->vm_end - vma->vm_start;
2140 offset += phdr.p_filesz;
2141 phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
2142 if (vma->vm_flags & VM_WRITE)
2143 phdr.p_flags |= PF_W;
2144 if (vma->vm_flags & VM_EXEC)
2145 phdr.p_flags |= PF_X;
2146 phdr.p_align = ELF_EXEC_PAGESIZE;
2147
2148 size += sizeof(phdr);
2149 if (size > cprm->limit
2150 || !dump_write(cprm->file, &phdr, sizeof(phdr)))
2151 goto end_coredump;
2152 }
2153
2154 if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit))
2155 goto end_coredump;
2156
2157 /* write out the notes section */
2158 if (!write_note_info(&info, cprm->file, &foffset))
2159 goto end_coredump;
2160
2161 if (elf_coredump_extra_notes_write(cprm->file, &foffset))
2162 goto end_coredump;
2163
2164 /* Align to page */
2165 if (!dump_seek(cprm->file, dataoff - foffset))
2166 goto end_coredump;
2167
2168 for (vma = first_vma(current, gate_vma); vma != NULL;
2169 vma = next_vma(vma, gate_vma)) {
2170 unsigned long addr;
2171 unsigned long end;
2172
2173 end = vma->vm_start + vma_dump_size(vma, cprm->mm_flags);
2174
2175 for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
2176 struct page *page;
2177 int stop;
2178
2179 page = get_dump_page(addr);
2180 if (page) {
2181 void *kaddr = kmap(page);
2182 stop = ((size += PAGE_SIZE) > cprm->limit) ||
2183 !dump_write(cprm->file, kaddr,
2184 PAGE_SIZE);
2185 kunmap(page);
2186 page_cache_release(page);
2187 } else
2188 stop = !dump_seek(cprm->file, PAGE_SIZE);
2189 if (stop)
2190 goto end_coredump;
2191 }
2192 }
2193
2194 if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit))
2195 goto end_coredump;
2196
2197 if (e_phnum == PN_XNUM) {
2198 size += sizeof(*shdr4extnum);
2199 if (size > cprm->limit
2200 || !dump_write(cprm->file, shdr4extnum,
2201 sizeof(*shdr4extnum)))
2202 goto end_coredump;
2203 }
2204
2205 end_coredump:
2206 set_fs(fs);
2207
2208 cleanup:
2209 free_note_info(&info);
2210 kfree(shdr4extnum);
2211 kfree(phdr4note);
2212 kfree(elf);
2213 out:
2214 return has_dumped;
2215 }
2216
2217 #endif /* CONFIG_ELF_CORE */
2218
2219 static int __init init_elf_binfmt(void)
2220 {
2221 register_binfmt(&elf_format);
2222 return 0;
2223 }
2224
2225 static void __exit exit_elf_binfmt(void)
2226 {
2227 /* Remove the COFF and ELF loaders. */
2228 unregister_binfmt(&elf_format);
2229 }
2230
2231 core_initcall(init_elf_binfmt);
2232 module_exit(exit_elf_binfmt);
2233 MODULE_LICENSE("GPL");
kernel source for telekom puls (alcatel/mediatek)