2 * linux/fs/binfmt_elf.c
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
9 * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com).
12 #include <linux/module.h>
13 #include <linux/kernel.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>
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);
45 * If we don't support core dumping, then supply a NULL so we
48 #ifdef CONFIG_ELF_CORE
49 static int elf_core_dump(struct coredump_params
*cprm
);
51 #define elf_core_dump NULL
54 #if ELF_EXEC_PAGESIZE > PAGE_SIZE
55 #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
57 #define ELF_MIN_ALIGN PAGE_SIZE
60 #ifndef ELF_CORE_EFLAGS
61 #define ELF_CORE_EFLAGS 0
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))
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
,
76 #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
78 static int set_brk(unsigned long start
, unsigned long end
)
80 start
= ELF_PAGEALIGN(start
);
81 end
= ELF_PAGEALIGN(end
);
84 down_write(¤t
->mm
->mmap_sem
);
85 addr
= do_brk(start
, end
- start
);
86 up_write(¤t
->mm
->mmap_sem
);
90 current
->mm
->start_brk
= current
->mm
->brk
= end
;
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
99 static int padzero(unsigned long elf_bss
)
103 nbyte
= ELF_PAGEOFFSET(elf_bss
);
105 nbyte
= ELF_MIN_ALIGN
- nbyte
;
106 if (clear_user((void __user
*) elf_bss
, nbyte
))
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; \
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; })
127 #ifndef ELF_BASE_PLATFORM
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.
133 #define ELF_BASE_PLATFORM NULL
137 create_elf_tables(struct linux_binprm
*bprm
, struct elfhdr
*exec
,
138 unsigned long load_addr
, unsigned long interp_load_addr
)
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];
153 elf_addr_t
*elf_info
;
155 const struct cred
*cred
= current_cred();
156 struct vm_area_struct
*vma
;
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.
164 p
= arch_align_stack(p
);
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
174 size_t len
= strlen(k_platform
) + 1;
176 u_platform
= (elf_addr_t __user
*)STACK_ALLOC(p
, len
);
177 if (__copy_to_user(u_platform
, k_platform
, len
))
182 * If this architecture has a "base" platform capability
183 * string, copy it to userspace.
185 u_base_platform
= NULL
;
186 if (k_base_platform
) {
187 size_t len
= strlen(k_base_platform
) + 1;
189 u_base_platform
= (elf_addr_t __user
*)STACK_ALLOC(p
, len
);
190 if (__copy_to_user(u_base_platform
, k_base_platform
, len
))
195 * Generate 16 random bytes for userspace PRNG seeding.
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
)))
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) \
208 elf_info[ei_index++] = id; \
209 elf_info[ei_index++] = val; \
214 * ARCH_DLINFO must come first so PPC can do its special alignment of
216 * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
217 * ARCH_DLINFO changes
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
);
238 NEW_AUX_ENT(AT_PLATFORM
,
239 (elf_addr_t
)(unsigned long)u_platform
);
241 if (k_base_platform
) {
242 NEW_AUX_ENT(AT_BASE_PLATFORM
,
243 (elf_addr_t
)(unsigned long)u_base_platform
);
245 if (bprm
->interp_flags
& BINPRM_FLAGS_EXECFD
) {
246 NEW_AUX_ENT(AT_EXECFD
, bprm
->interp_data
);
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]);
253 /* And advance past the AT_NULL entry. */
256 sp
= STACK_ADD(p
, ei_index
);
258 items
= (argc
+ 1) + (envc
+ 1) + 1;
259 bprm
->p
= STACK_ROUND(sp
, items
);
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 */
266 sp
= (elf_addr_t __user
*)bprm
->p
;
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.
274 vma
= find_extend_vma(current
->mm
, bprm
->p
);
278 /* Now, let's put argc (and argv, envp if appropriate) on the stack */
279 if (__put_user(argc
, sp
++))
282 envp
= argv
+ argc
+ 1;
284 /* Populate argv and envp */
285 p
= current
->mm
->arg_end
= current
->mm
->arg_start
;
288 if (__put_user((elf_addr_t
)p
, argv
++))
290 len
= strnlen_user((void __user
*)p
, MAX_ARG_STRLEN
);
291 if (!len
|| len
> MAX_ARG_STRLEN
)
295 if (__put_user(0, argv
))
297 current
->mm
->arg_end
= current
->mm
->env_start
= p
;
300 if (__put_user((elf_addr_t
)p
, envp
++))
302 len
= strnlen_user((void __user
*)p
, MAX_ARG_STRLEN
);
303 if (!len
|| len
> MAX_ARG_STRLEN
)
307 if (__put_user(0, envp
))
309 current
->mm
->env_end
= p
;
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
)))
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
)
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
);
328 /* mmap() will return -EINVAL if given a zero size, but a
329 * segment with zero filesize is perfectly valid */
333 down_write(¤t
->mm
->mmap_sem
);
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.)
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
);
348 map_addr
= do_mmap(filep
, addr
, size
, prot
, type
, off
);
350 up_write(¤t
->mm
->mmap_sem
);
354 static unsigned long total_mapping_size(struct elf_phdr
*cmds
, int nr
)
356 int i
, first_idx
= -1, last_idx
= -1;
358 for (i
= 0; i
< nr
; i
++) {
359 if (cmds
[i
].p_type
== PT_LOAD
) {
368 return cmds
[last_idx
].p_vaddr
+ cmds
[last_idx
].p_memsz
-
369 ELF_PAGESTART(cmds
[first_idx
].p_vaddr
);
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
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
)
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
;
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
)
395 if (!elf_check_arch(interp_elf_ex
))
397 if (!interpreter
->f_op
|| !interpreter
->f_op
->mmap
)
401 * If the size of this structure has changed, then punt, since
402 * we will be doing the wrong thing.
404 if (interp_elf_ex
->e_phentsize
!= sizeof(struct elf_phdr
))
406 if (interp_elf_ex
->e_phnum
< 1 ||
407 interp_elf_ex
->e_phnum
> 65536U / sizeof(struct elf_phdr
))
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
)
414 elf_phdata
= kmalloc(size
, GFP_KERNEL
);
418 retval
= kernel_read(interpreter
, interp_elf_ex
->e_phoff
,
419 (char *)elf_phdata
, size
);
421 if (retval
!= size
) {
427 total_size
= total_mapping_size(elf_phdata
, interp_elf_ex
->e_phnum
);
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
;
438 unsigned long vaddr
= 0;
439 unsigned long k
, map_addr
;
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
)
453 map_addr
= elf_map(interpreter
, load_addr
+ vaddr
,
454 eppnt
, elf_prot
, elf_type
, total_size
);
456 if (!*interp_map_addr
)
457 *interp_map_addr
= map_addr
;
459 if (BAD_ADDR(map_addr
))
462 if (!load_addr_set
&&
463 interp_elf_ex
->e_type
== ET_DYN
) {
464 load_addr
= map_addr
- ELF_PAGESTART(vaddr
);
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.
473 k
= load_addr
+ eppnt
->p_vaddr
;
475 eppnt
->p_filesz
> eppnt
->p_memsz
||
476 eppnt
->p_memsz
> TASK_SIZE
||
477 TASK_SIZE
- eppnt
->p_memsz
< k
) {
483 * Find the end of the file mapping for this phdr, and
484 * keep track of the largest address we see for this.
486 k
= load_addr
+ eppnt
->p_vaddr
+ eppnt
->p_filesz
;
491 * Do the same thing for the memory mapping - between
492 * elf_bss and last_bss is the bss section.
494 k
= load_addr
+ eppnt
->p_memsz
+ eppnt
->p_vaddr
;
500 if (last_bss
> elf_bss
) {
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
507 if (padzero(elf_bss
)) {
512 /* What we have mapped so far */
513 elf_bss
= ELF_PAGESTART(elf_bss
+ ELF_MIN_ALIGN
- 1);
515 /* Map the last of the bss segment */
516 down_write(¤t
->mm
->mmap_sem
);
517 error
= do_brk(elf_bss
, last_bss
- elf_bss
);
518 up_write(¤t
->mm
->mmap_sem
);
532 * These are the functions used to load ELF style executables and shared
533 * libraries. There is no binary dependent code anywhere else.
536 #define INTERPRETER_NONE 0
537 #define INTERPRETER_ELF 2
539 #ifndef STACK_RND_MASK
540 #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
543 static unsigned long randomize_stack_top(unsigned long stack_top
)
545 unsigned int random_variable
= 0;
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
;
552 #ifdef CONFIG_STACK_GROWSUP
553 return PAGE_ALIGN(stack_top
) + random_variable
;
555 return PAGE_ALIGN(stack_top
) - random_variable
;
559 static int load_elf_binary(struct linux_binprm
*bprm
, struct pt_regs
*regs
)
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
;
566 struct elf_phdr
*elf_ppnt
, *elf_phdata
;
567 unsigned long elf_bss
, elf_brk
;
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;
577 struct elfhdr elf_ex
;
578 struct elfhdr interp_elf_ex
;
581 loc
= kmalloc(sizeof(*loc
), GFP_KERNEL
);
587 /* Get the exec-header */
588 loc
->elf_ex
= *((struct elfhdr
*)bprm
->buf
);
591 /* First of all, some simple consistency checks */
592 if (memcmp(loc
->elf_ex
.e_ident
, ELFMAG
, SELFMAG
) != 0)
595 if (loc
->elf_ex
.e_type
!= ET_EXEC
&& loc
->elf_ex
.e_type
!= ET_DYN
)
597 if (!elf_check_arch(&loc
->elf_ex
))
599 if (!bprm
->file
->f_op
|| !bprm
->file
->f_op
->mmap
)
602 /* Now read in all of the header information */
603 if (loc
->elf_ex
.e_phentsize
!= sizeof(struct elf_phdr
))
605 if (loc
->elf_ex
.e_phnum
< 1 ||
606 loc
->elf_ex
.e_phnum
> 65536U / sizeof(struct elf_phdr
))
608 size
= loc
->elf_ex
.e_phnum
* sizeof(struct elf_phdr
);
610 elf_phdata
= kmalloc(size
, GFP_KERNEL
);
614 retval
= kernel_read(bprm
->file
, loc
->elf_ex
.e_phoff
,
615 (char *)elf_phdata
, size
);
616 if (retval
!= size
) {
622 elf_ppnt
= elf_phdata
;
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
638 if (elf_ppnt
->p_filesz
> PATH_MAX
||
639 elf_ppnt
->p_filesz
< 2)
643 elf_interpreter
= kmalloc(elf_ppnt
->p_filesz
,
645 if (!elf_interpreter
)
648 retval
= kernel_read(bprm
->file
, elf_ppnt
->p_offset
,
651 if (retval
!= elf_ppnt
->p_filesz
) {
654 goto out_free_interp
;
656 /* make sure path is NULL terminated */
658 if (elf_interpreter
[elf_ppnt
->p_filesz
- 1] != '\0')
659 goto out_free_interp
;
661 interpreter
= open_exec(elf_interpreter
);
662 retval
= PTR_ERR(interpreter
);
663 if (IS_ERR(interpreter
))
664 goto out_free_interp
;
667 * If the binary is not readable then enforce
668 * mm->dumpable = 0 regardless of the interpreter's
671 if (file_permission(interpreter
, MAY_READ
) < 0)
672 bprm
->interp_flags
|= BINPRM_FLAGS_ENFORCE_NONDUMP
;
674 retval
= kernel_read(interpreter
, 0, bprm
->buf
,
676 if (retval
!= BINPRM_BUF_SIZE
) {
679 goto out_free_dentry
;
682 /* Get the exec headers */
683 loc
->interp_elf_ex
= *((struct elfhdr
*)bprm
->buf
);
689 elf_ppnt
= elf_phdata
;
690 for (i
= 0; i
< loc
->elf_ex
.e_phnum
; i
++, elf_ppnt
++)
691 if (elf_ppnt
->p_type
== PT_GNU_STACK
) {
692 if (elf_ppnt
->p_flags
& PF_X
)
693 executable_stack
= EXSTACK_ENABLE_X
;
695 executable_stack
= EXSTACK_DISABLE_X
;
699 /* Some simple consistency checks for the interpreter */
700 if (elf_interpreter
) {
702 /* Not an ELF interpreter */
703 if (memcmp(loc
->interp_elf_ex
.e_ident
, ELFMAG
, SELFMAG
) != 0)
704 goto out_free_dentry
;
705 /* Verify the interpreter has a valid arch */
706 if (!elf_check_arch(&loc
->interp_elf_ex
))
707 goto out_free_dentry
;
710 /* Flush all traces of the currently running executable */
711 retval
= flush_old_exec(bprm
);
713 goto out_free_dentry
;
715 /* OK, This is the point of no return */
716 current
->flags
&= ~PF_FORKNOEXEC
;
717 current
->mm
->def_flags
= def_flags
;
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
;
725 if (!(current
->personality
& ADDR_NO_RANDOMIZE
) && randomize_va_space
)
726 current
->flags
|= PF_RANDOMIZE
;
728 setup_new_exec(bprm
);
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
),
737 send_sig(SIGKILL
, current
, 0);
738 goto out_free_dentry
;
741 current
->mm
->start_stack
= bprm
->p
;
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
;
750 if (elf_ppnt
->p_type
!= PT_LOAD
)
753 if (unlikely (elf_brk
> elf_bss
)) {
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
);
762 send_sig(SIGKILL
, current
, 0);
763 goto out_free_dentry
;
765 nbyte
= ELF_PAGEOFFSET(elf_bss
);
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
+
773 * This bss-zeroing can fail if the ELF
774 * file specifies odd protections. So
775 * we don't check the return value
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
;
788 elf_flags
= MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
;
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 #if defined(CONFIG_X86) || defined(CONFIG_ARM)
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.
805 if (current
->flags
& PF_RANDOMIZE
)
808 load_bias
= ELF_PAGESTART(ELF_ET_DYN_BASE
- vaddr
);
810 load_bias
= ELF_PAGESTART(ELF_ET_DYN_BASE
- vaddr
);
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
;
823 if (!load_addr_set
) {
825 load_addr
= (elf_ppnt
->p_vaddr
- elf_ppnt
->p_offset
);
826 if (loc
->elf_ex
.e_type
== ET_DYN
) {
828 ELF_PAGESTART(load_bias
+ vaddr
);
829 load_addr
+= load_bias
;
830 reloc_func_desc
= load_bias
;
833 k
= elf_ppnt
->p_vaddr
;
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.
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);
850 goto out_free_dentry
;
853 k
= elf_ppnt
->p_vaddr
+ elf_ppnt
->p_filesz
;
857 if ((elf_ppnt
->p_flags
& PF_X
) && end_code
< k
)
861 k
= elf_ppnt
->p_vaddr
+ elf_ppnt
->p_memsz
;
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
;
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.
879 retval
= set_brk(elf_bss
, elf_brk
);
881 send_sig(SIGKILL
, current
, 0);
882 goto out_free_dentry
;
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
;
890 if (elf_interpreter
) {
891 unsigned long uninitialized_var(interp_map_addr
);
893 elf_entry
= load_elf_interp(&loc
->interp_elf_ex
,
897 if (!IS_ERR((void *)elf_entry
)) {
899 * load_elf_interp() returns relocation
902 interp_load_addr
= elf_entry
;
903 elf_entry
+= loc
->interp_elf_ex
.e_entry
;
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
;
911 reloc_func_desc
= interp_load_addr
;
913 allow_write_access(interpreter
);
915 kfree(elf_interpreter
);
917 elf_entry
= loc
->elf_ex
.e_entry
;
918 if (BAD_ADDR(elf_entry
)) {
919 force_sig(SIGSEGV
, current
);
921 goto out_free_dentry
;
927 set_binfmt(&elf_format
);
929 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
930 retval
= arch_setup_additional_pages(bprm
, !!elf_interpreter
);
932 send_sig(SIGKILL
, current
, 0);
935 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
937 install_exec_creds(bprm
);
938 current
->flags
&= ~PF_FORKNOEXEC
;
939 retval
= create_elf_tables(bprm
, &loc
->elf_ex
,
940 load_addr
, interp_load_addr
);
942 send_sig(SIGKILL
, current
, 0);
945 /* N.B. passed_fileno might not be initialized? */
946 current
->mm
->end_code
= end_code
;
947 current
->mm
->start_code
= start_code
;
948 current
->mm
->start_data
= start_data
;
949 current
->mm
->end_data
= end_data
;
950 current
->mm
->start_stack
= bprm
->p
;
952 #ifdef arch_randomize_brk
953 if ((current
->flags
& PF_RANDOMIZE
) && (randomize_va_space
> 1)) {
954 current
->mm
->brk
= current
->mm
->start_brk
=
955 arch_randomize_brk(current
->mm
);
956 #ifdef CONFIG_COMPAT_BRK
957 current
->brk_randomized
= 1;
962 if (current
->personality
& MMAP_PAGE_ZERO
) {
963 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
964 and some applications "depend" upon this behavior.
965 Since we do not have the power to recompile these, we
966 emulate the SVr4 behavior. Sigh. */
967 down_write(¤t
->mm
->mmap_sem
);
968 error
= do_mmap(NULL
, 0, PAGE_SIZE
, PROT_READ
| PROT_EXEC
,
969 MAP_FIXED
| MAP_PRIVATE
, 0);
970 up_write(¤t
->mm
->mmap_sem
);
975 * The ABI may specify that certain registers be set up in special
976 * ways (on i386 %edx is the address of a DT_FINI function, for
977 * example. In addition, it may also specify (eg, PowerPC64 ELF)
978 * that the e_entry field is the address of the function descriptor
979 * for the startup routine, rather than the address of the startup
980 * routine itself. This macro performs whatever initialization to
981 * the regs structure is required as well as any relocations to the
982 * function descriptor entries when executing dynamically links apps.
984 ELF_PLAT_INIT(regs
, reloc_func_desc
);
987 start_thread(regs
, elf_entry
, bprm
->p
);
996 allow_write_access(interpreter
);
1000 kfree(elf_interpreter
);
1006 /* This is really simpleminded and specialized - we are loading an
1007 a.out library that is given an ELF header. */
1008 static int load_elf_library(struct file
*file
)
1010 struct elf_phdr
*elf_phdata
;
1011 struct elf_phdr
*eppnt
;
1012 unsigned long elf_bss
, bss
, len
;
1013 int retval
, error
, i
, j
;
1014 struct elfhdr elf_ex
;
1017 retval
= kernel_read(file
, 0, (char *)&elf_ex
, sizeof(elf_ex
));
1018 if (retval
!= sizeof(elf_ex
))
1021 if (memcmp(elf_ex
.e_ident
, ELFMAG
, SELFMAG
) != 0)
1024 /* First of all, some simple consistency checks */
1025 if (elf_ex
.e_type
!= ET_EXEC
|| elf_ex
.e_phnum
> 2 ||
1026 !elf_check_arch(&elf_ex
) || !file
->f_op
|| !file
->f_op
->mmap
)
1029 /* Now read in all of the header information */
1031 j
= sizeof(struct elf_phdr
) * elf_ex
.e_phnum
;
1032 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1035 elf_phdata
= kmalloc(j
, GFP_KERNEL
);
1041 retval
= kernel_read(file
, elf_ex
.e_phoff
, (char *)eppnt
, j
);
1045 for (j
= 0, i
= 0; i
<elf_ex
.e_phnum
; i
++)
1046 if ((eppnt
+ i
)->p_type
== PT_LOAD
)
1051 while (eppnt
->p_type
!= PT_LOAD
)
1054 /* Now use mmap to map the library into memory. */
1055 down_write(¤t
->mm
->mmap_sem
);
1056 error
= do_mmap(file
,
1057 ELF_PAGESTART(eppnt
->p_vaddr
),
1059 ELF_PAGEOFFSET(eppnt
->p_vaddr
)),
1060 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
1061 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
,
1063 ELF_PAGEOFFSET(eppnt
->p_vaddr
)));
1064 up_write(¤t
->mm
->mmap_sem
);
1065 if (error
!= ELF_PAGESTART(eppnt
->p_vaddr
))
1068 elf_bss
= eppnt
->p_vaddr
+ eppnt
->p_filesz
;
1069 if (padzero(elf_bss
)) {
1074 len
= ELF_PAGESTART(eppnt
->p_filesz
+ eppnt
->p_vaddr
+
1076 bss
= eppnt
->p_memsz
+ eppnt
->p_vaddr
;
1078 down_write(¤t
->mm
->mmap_sem
);
1079 do_brk(len
, bss
- len
);
1080 up_write(¤t
->mm
->mmap_sem
);
1090 #ifdef CONFIG_ELF_CORE
1094 * Modelled on fs/exec.c:aout_core_dump()
1095 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1099 * Decide what to dump of a segment, part, all or none.
1101 static unsigned long vma_dump_size(struct vm_area_struct
*vma
,
1102 unsigned long mm_flags
)
1104 #define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1106 /* The vma can be set up to tell us the answer directly. */
1107 if (vma
->vm_flags
& VM_ALWAYSDUMP
)
1110 /* Hugetlb memory check */
1111 if (vma
->vm_flags
& VM_HUGETLB
) {
1112 if ((vma
->vm_flags
& VM_SHARED
) && FILTER(HUGETLB_SHARED
))
1114 if (!(vma
->vm_flags
& VM_SHARED
) && FILTER(HUGETLB_PRIVATE
))
1118 /* Do not dump I/O mapped devices or special mappings */
1119 if (vma
->vm_flags
& (VM_IO
| VM_RESERVED
))
1122 /* By default, dump shared memory if mapped from an anonymous file. */
1123 if (vma
->vm_flags
& VM_SHARED
) {
1124 if (vma
->vm_file
->f_path
.dentry
->d_inode
->i_nlink
== 0 ?
1125 FILTER(ANON_SHARED
) : FILTER(MAPPED_SHARED
))
1130 /* Dump segments that have been written to. */
1131 if (vma
->anon_vma
&& FILTER(ANON_PRIVATE
))
1133 if (vma
->vm_file
== NULL
)
1136 if (FILTER(MAPPED_PRIVATE
))
1140 * If this looks like the beginning of a DSO or executable mapping,
1141 * check for an ELF header. If we find one, dump the first page to
1142 * aid in determining what was mapped here.
1144 if (FILTER(ELF_HEADERS
) &&
1145 vma
->vm_pgoff
== 0 && (vma
->vm_flags
& VM_READ
)) {
1146 u32 __user
*header
= (u32 __user
*) vma
->vm_start
;
1148 mm_segment_t fs
= get_fs();
1150 * Doing it this way gets the constant folded by GCC.
1154 char elfmag
[SELFMAG
];
1156 BUILD_BUG_ON(SELFMAG
!= sizeof word
);
1157 magic
.elfmag
[EI_MAG0
] = ELFMAG0
;
1158 magic
.elfmag
[EI_MAG1
] = ELFMAG1
;
1159 magic
.elfmag
[EI_MAG2
] = ELFMAG2
;
1160 magic
.elfmag
[EI_MAG3
] = ELFMAG3
;
1162 * Switch to the user "segment" for get_user(),
1163 * then put back what elf_core_dump() had in place.
1166 if (unlikely(get_user(word
, header
)))
1169 if (word
== magic
.cmp
)
1178 return vma
->vm_end
- vma
->vm_start
;
1181 /* An ELF note in memory */
1186 unsigned int datasz
;
1190 static int notesize(struct memelfnote
*en
)
1194 sz
= sizeof(struct elf_note
);
1195 sz
+= roundup(strlen(en
->name
) + 1, 4);
1196 sz
+= roundup(en
->datasz
, 4);
1201 #define DUMP_WRITE(addr, nr, foffset) \
1202 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
1204 static int alignfile(struct file
*file
, loff_t
*foffset
)
1206 static const char buf
[4] = { 0, };
1207 DUMP_WRITE(buf
, roundup(*foffset
, 4) - *foffset
, foffset
);
1211 static int writenote(struct memelfnote
*men
, struct file
*file
,
1215 en
.n_namesz
= strlen(men
->name
) + 1;
1216 en
.n_descsz
= men
->datasz
;
1217 en
.n_type
= men
->type
;
1219 DUMP_WRITE(&en
, sizeof(en
), foffset
);
1220 DUMP_WRITE(men
->name
, en
.n_namesz
, foffset
);
1221 if (!alignfile(file
, foffset
))
1223 DUMP_WRITE(men
->data
, men
->datasz
, foffset
);
1224 if (!alignfile(file
, foffset
))
1231 static void fill_elf_header(struct elfhdr
*elf
, int segs
,
1232 u16 machine
, u32 flags
, u8 osabi
)
1234 memset(elf
, 0, sizeof(*elf
));
1236 memcpy(elf
->e_ident
, ELFMAG
, SELFMAG
);
1237 elf
->e_ident
[EI_CLASS
] = ELF_CLASS
;
1238 elf
->e_ident
[EI_DATA
] = ELF_DATA
;
1239 elf
->e_ident
[EI_VERSION
] = EV_CURRENT
;
1240 elf
->e_ident
[EI_OSABI
] = ELF_OSABI
;
1242 elf
->e_type
= ET_CORE
;
1243 elf
->e_machine
= machine
;
1244 elf
->e_version
= EV_CURRENT
;
1245 elf
->e_phoff
= sizeof(struct elfhdr
);
1246 elf
->e_flags
= flags
;
1247 elf
->e_ehsize
= sizeof(struct elfhdr
);
1248 elf
->e_phentsize
= sizeof(struct elf_phdr
);
1249 elf
->e_phnum
= segs
;
1254 static void fill_elf_note_phdr(struct elf_phdr
*phdr
, int sz
, loff_t offset
)
1256 phdr
->p_type
= PT_NOTE
;
1257 phdr
->p_offset
= offset
;
1260 phdr
->p_filesz
= sz
;
1267 static void fill_note(struct memelfnote
*note
, const char *name
, int type
,
1268 unsigned int sz
, void *data
)
1278 * fill up all the fields in prstatus from the given task struct, except
1279 * registers which need to be filled up separately.
1281 static void fill_prstatus(struct elf_prstatus
*prstatus
,
1282 struct task_struct
*p
, long signr
)
1284 prstatus
->pr_info
.si_signo
= prstatus
->pr_cursig
= signr
;
1285 prstatus
->pr_sigpend
= p
->pending
.signal
.sig
[0];
1286 prstatus
->pr_sighold
= p
->blocked
.sig
[0];
1288 prstatus
->pr_ppid
= task_pid_vnr(rcu_dereference(p
->real_parent
));
1290 prstatus
->pr_pid
= task_pid_vnr(p
);
1291 prstatus
->pr_pgrp
= task_pgrp_vnr(p
);
1292 prstatus
->pr_sid
= task_session_vnr(p
);
1293 if (thread_group_leader(p
)) {
1294 struct task_cputime cputime
;
1297 * This is the record for the group leader. It shows the
1298 * group-wide total, not its individual thread total.
1300 thread_group_cputime(p
, &cputime
);
1301 cputime_to_timeval(cputime
.utime
, &prstatus
->pr_utime
);
1302 cputime_to_timeval(cputime
.stime
, &prstatus
->pr_stime
);
1304 cputime_to_timeval(p
->utime
, &prstatus
->pr_utime
);
1305 cputime_to_timeval(p
->stime
, &prstatus
->pr_stime
);
1307 cputime_to_timeval(p
->signal
->cutime
, &prstatus
->pr_cutime
);
1308 cputime_to_timeval(p
->signal
->cstime
, &prstatus
->pr_cstime
);
1311 static int fill_psinfo(struct elf_prpsinfo
*psinfo
, struct task_struct
*p
,
1312 struct mm_struct
*mm
)
1314 const struct cred
*cred
;
1315 unsigned int i
, len
;
1317 /* first copy the parameters from user space */
1318 memset(psinfo
, 0, sizeof(struct elf_prpsinfo
));
1320 len
= mm
->arg_end
- mm
->arg_start
;
1321 if (len
>= ELF_PRARGSZ
)
1322 len
= ELF_PRARGSZ
-1;
1323 if (copy_from_user(&psinfo
->pr_psargs
,
1324 (const char __user
*)mm
->arg_start
, len
))
1326 for(i
= 0; i
< len
; i
++)
1327 if (psinfo
->pr_psargs
[i
] == 0)
1328 psinfo
->pr_psargs
[i
] = ' ';
1329 psinfo
->pr_psargs
[len
] = 0;
1332 psinfo
->pr_ppid
= task_pid_vnr(rcu_dereference(p
->real_parent
));
1334 psinfo
->pr_pid
= task_pid_vnr(p
);
1335 psinfo
->pr_pgrp
= task_pgrp_vnr(p
);
1336 psinfo
->pr_sid
= task_session_vnr(p
);
1338 i
= p
->state
? ffz(~p
->state
) + 1 : 0;
1339 psinfo
->pr_state
= i
;
1340 psinfo
->pr_sname
= (i
> 5) ? '.' : "RSDTZW"[i
];
1341 psinfo
->pr_zomb
= psinfo
->pr_sname
== 'Z';
1342 psinfo
->pr_nice
= task_nice(p
);
1343 psinfo
->pr_flag
= p
->flags
;
1345 cred
= __task_cred(p
);
1346 SET_UID(psinfo
->pr_uid
, cred
->uid
);
1347 SET_GID(psinfo
->pr_gid
, cred
->gid
);
1349 strncpy(psinfo
->pr_fname
, p
->comm
, sizeof(psinfo
->pr_fname
));
1354 static void fill_auxv_note(struct memelfnote
*note
, struct mm_struct
*mm
)
1356 elf_addr_t
*auxv
= (elf_addr_t
*) mm
->saved_auxv
;
1360 while (auxv
[i
- 2] != AT_NULL
);
1361 fill_note(note
, "CORE", NT_AUXV
, i
* sizeof(elf_addr_t
), auxv
);
1364 #ifdef CORE_DUMP_USE_REGSET
1365 #include <linux/regset.h>
1367 struct elf_thread_core_info
{
1368 struct elf_thread_core_info
*next
;
1369 struct task_struct
*task
;
1370 struct elf_prstatus prstatus
;
1371 struct memelfnote notes
[0];
1374 struct elf_note_info
{
1375 struct elf_thread_core_info
*thread
;
1376 struct memelfnote psinfo
;
1377 struct memelfnote auxv
;
1383 * When a regset has a writeback hook, we call it on each thread before
1384 * dumping user memory. On register window machines, this makes sure the
1385 * user memory backing the register data is up to date before we read it.
1387 static void do_thread_regset_writeback(struct task_struct
*task
,
1388 const struct user_regset
*regset
)
1390 if (regset
->writeback
)
1391 regset
->writeback(task
, regset
, 1);
1394 static int fill_thread_core_info(struct elf_thread_core_info
*t
,
1395 const struct user_regset_view
*view
,
1396 long signr
, size_t *total
)
1401 * NT_PRSTATUS is the one special case, because the regset data
1402 * goes into the pr_reg field inside the note contents, rather
1403 * than being the whole note contents. We fill the reset in here.
1404 * We assume that regset 0 is NT_PRSTATUS.
1406 fill_prstatus(&t
->prstatus
, t
->task
, signr
);
1407 (void) view
->regsets
[0].get(t
->task
, &view
->regsets
[0],
1408 0, sizeof(t
->prstatus
.pr_reg
),
1409 &t
->prstatus
.pr_reg
, NULL
);
1411 fill_note(&t
->notes
[0], "CORE", NT_PRSTATUS
,
1412 sizeof(t
->prstatus
), &t
->prstatus
);
1413 *total
+= notesize(&t
->notes
[0]);
1415 do_thread_regset_writeback(t
->task
, &view
->regsets
[0]);
1418 * Each other regset might generate a note too. For each regset
1419 * that has no core_note_type or is inactive, we leave t->notes[i]
1420 * all zero and we'll know to skip writing it later.
1422 for (i
= 1; i
< view
->n
; ++i
) {
1423 const struct user_regset
*regset
= &view
->regsets
[i
];
1424 do_thread_regset_writeback(t
->task
, regset
);
1425 if (regset
->core_note_type
&&
1426 (!regset
->active
|| regset
->active(t
->task
, regset
))) {
1428 size_t size
= regset
->n
* regset
->size
;
1429 void *data
= kmalloc(size
, GFP_KERNEL
);
1430 if (unlikely(!data
))
1432 ret
= regset
->get(t
->task
, regset
,
1433 0, size
, data
, NULL
);
1437 if (regset
->core_note_type
!= NT_PRFPREG
)
1438 fill_note(&t
->notes
[i
], "LINUX",
1439 regset
->core_note_type
,
1442 t
->prstatus
.pr_fpvalid
= 1;
1443 fill_note(&t
->notes
[i
], "CORE",
1444 NT_PRFPREG
, size
, data
);
1446 *total
+= notesize(&t
->notes
[i
]);
1454 static int fill_note_info(struct elfhdr
*elf
, int phdrs
,
1455 struct elf_note_info
*info
,
1456 long signr
, struct pt_regs
*regs
)
1458 struct task_struct
*dump_task
= current
;
1459 const struct user_regset_view
*view
= task_user_regset_view(dump_task
);
1460 struct elf_thread_core_info
*t
;
1461 struct elf_prpsinfo
*psinfo
;
1462 struct core_thread
*ct
;
1466 info
->thread
= NULL
;
1468 psinfo
= kmalloc(sizeof(*psinfo
), GFP_KERNEL
);
1472 fill_note(&info
->psinfo
, "CORE", NT_PRPSINFO
, sizeof(*psinfo
), psinfo
);
1475 * Figure out how many notes we're going to need for each thread.
1477 info
->thread_notes
= 0;
1478 for (i
= 0; i
< view
->n
; ++i
)
1479 if (view
->regsets
[i
].core_note_type
!= 0)
1480 ++info
->thread_notes
;
1483 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1484 * since it is our one special case.
1486 if (unlikely(info
->thread_notes
== 0) ||
1487 unlikely(view
->regsets
[0].core_note_type
!= NT_PRSTATUS
)) {
1493 * Initialize the ELF file header.
1495 fill_elf_header(elf
, phdrs
,
1496 view
->e_machine
, view
->e_flags
, view
->ei_osabi
);
1499 * Allocate a structure for each thread.
1501 for (ct
= &dump_task
->mm
->core_state
->dumper
; ct
; ct
= ct
->next
) {
1502 t
= kzalloc(offsetof(struct elf_thread_core_info
,
1503 notes
[info
->thread_notes
]),
1509 if (ct
->task
== dump_task
|| !info
->thread
) {
1510 t
->next
= info
->thread
;
1514 * Make sure to keep the original task at
1515 * the head of the list.
1517 t
->next
= info
->thread
->next
;
1518 info
->thread
->next
= t
;
1523 * Now fill in each thread's information.
1525 for (t
= info
->thread
; t
!= NULL
; t
= t
->next
)
1526 if (!fill_thread_core_info(t
, view
, signr
, &info
->size
))
1530 * Fill in the two process-wide notes.
1532 fill_psinfo(psinfo
, dump_task
->group_leader
, dump_task
->mm
);
1533 info
->size
+= notesize(&info
->psinfo
);
1535 fill_auxv_note(&info
->auxv
, current
->mm
);
1536 info
->size
+= notesize(&info
->auxv
);
1541 static size_t get_note_info_size(struct elf_note_info
*info
)
1547 * Write all the notes for each thread. When writing the first thread, the
1548 * process-wide notes are interleaved after the first thread-specific note.
1550 static int write_note_info(struct elf_note_info
*info
,
1551 struct file
*file
, loff_t
*foffset
)
1554 struct elf_thread_core_info
*t
= info
->thread
;
1559 if (!writenote(&t
->notes
[0], file
, foffset
))
1562 if (first
&& !writenote(&info
->psinfo
, file
, foffset
))
1564 if (first
&& !writenote(&info
->auxv
, file
, foffset
))
1567 for (i
= 1; i
< info
->thread_notes
; ++i
)
1568 if (t
->notes
[i
].data
&&
1569 !writenote(&t
->notes
[i
], file
, foffset
))
1579 static void free_note_info(struct elf_note_info
*info
)
1581 struct elf_thread_core_info
*threads
= info
->thread
;
1584 struct elf_thread_core_info
*t
= threads
;
1586 WARN_ON(t
->notes
[0].data
&& t
->notes
[0].data
!= &t
->prstatus
);
1587 for (i
= 1; i
< info
->thread_notes
; ++i
)
1588 kfree(t
->notes
[i
].data
);
1591 kfree(info
->psinfo
.data
);
1596 /* Here is the structure in which status of each thread is captured. */
1597 struct elf_thread_status
1599 struct list_head list
;
1600 struct elf_prstatus prstatus
; /* NT_PRSTATUS */
1601 elf_fpregset_t fpu
; /* NT_PRFPREG */
1602 struct task_struct
*thread
;
1603 #ifdef ELF_CORE_COPY_XFPREGS
1604 elf_fpxregset_t xfpu
; /* ELF_CORE_XFPREG_TYPE */
1606 struct memelfnote notes
[3];
1611 * In order to add the specific thread information for the elf file format,
1612 * we need to keep a linked list of every threads pr_status and then create
1613 * a single section for them in the final core file.
1615 static int elf_dump_thread_status(long signr
, struct elf_thread_status
*t
)
1618 struct task_struct
*p
= t
->thread
;
1621 fill_prstatus(&t
->prstatus
, p
, signr
);
1622 elf_core_copy_task_regs(p
, &t
->prstatus
.pr_reg
);
1624 fill_note(&t
->notes
[0], "CORE", NT_PRSTATUS
, sizeof(t
->prstatus
),
1627 sz
+= notesize(&t
->notes
[0]);
1629 if ((t
->prstatus
.pr_fpvalid
= elf_core_copy_task_fpregs(p
, NULL
,
1631 fill_note(&t
->notes
[1], "CORE", NT_PRFPREG
, sizeof(t
->fpu
),
1634 sz
+= notesize(&t
->notes
[1]);
1637 #ifdef ELF_CORE_COPY_XFPREGS
1638 if (elf_core_copy_task_xfpregs(p
, &t
->xfpu
)) {
1639 fill_note(&t
->notes
[2], "LINUX", ELF_CORE_XFPREG_TYPE
,
1640 sizeof(t
->xfpu
), &t
->xfpu
);
1642 sz
+= notesize(&t
->notes
[2]);
1648 struct elf_note_info
{
1649 struct memelfnote
*notes
;
1650 struct elf_prstatus
*prstatus
; /* NT_PRSTATUS */
1651 struct elf_prpsinfo
*psinfo
; /* NT_PRPSINFO */
1652 struct list_head thread_list
;
1653 elf_fpregset_t
*fpu
;
1654 #ifdef ELF_CORE_COPY_XFPREGS
1655 elf_fpxregset_t
*xfpu
;
1657 int thread_status_size
;
1661 static int elf_note_info_init(struct elf_note_info
*info
)
1663 memset(info
, 0, sizeof(*info
));
1664 INIT_LIST_HEAD(&info
->thread_list
);
1666 /* Allocate space for six ELF notes */
1667 info
->notes
= kmalloc(6 * sizeof(struct memelfnote
), GFP_KERNEL
);
1670 info
->psinfo
= kmalloc(sizeof(*info
->psinfo
), GFP_KERNEL
);
1673 info
->prstatus
= kmalloc(sizeof(*info
->prstatus
), GFP_KERNEL
);
1674 if (!info
->prstatus
)
1676 info
->fpu
= kmalloc(sizeof(*info
->fpu
), GFP_KERNEL
);
1679 #ifdef ELF_CORE_COPY_XFPREGS
1680 info
->xfpu
= kmalloc(sizeof(*info
->xfpu
), GFP_KERNEL
);
1685 #ifdef ELF_CORE_COPY_XFPREGS
1690 kfree(info
->prstatus
);
1692 kfree(info
->psinfo
);
1698 static int fill_note_info(struct elfhdr
*elf
, int phdrs
,
1699 struct elf_note_info
*info
,
1700 long signr
, struct pt_regs
*regs
)
1702 struct list_head
*t
;
1704 if (!elf_note_info_init(info
))
1708 struct core_thread
*ct
;
1709 struct elf_thread_status
*ets
;
1711 for (ct
= current
->mm
->core_state
->dumper
.next
;
1712 ct
; ct
= ct
->next
) {
1713 ets
= kzalloc(sizeof(*ets
), GFP_KERNEL
);
1717 ets
->thread
= ct
->task
;
1718 list_add(&ets
->list
, &info
->thread_list
);
1721 list_for_each(t
, &info
->thread_list
) {
1724 ets
= list_entry(t
, struct elf_thread_status
, list
);
1725 sz
= elf_dump_thread_status(signr
, ets
);
1726 info
->thread_status_size
+= sz
;
1729 /* now collect the dump for the current */
1730 memset(info
->prstatus
, 0, sizeof(*info
->prstatus
));
1731 fill_prstatus(info
->prstatus
, current
, signr
);
1732 elf_core_copy_regs(&info
->prstatus
->pr_reg
, regs
);
1735 fill_elf_header(elf
, phdrs
, ELF_ARCH
, ELF_CORE_EFLAGS
, ELF_OSABI
);
1738 * Set up the notes in similar form to SVR4 core dumps made
1739 * with info from their /proc.
1742 fill_note(info
->notes
+ 0, "CORE", NT_PRSTATUS
,
1743 sizeof(*info
->prstatus
), info
->prstatus
);
1744 fill_psinfo(info
->psinfo
, current
->group_leader
, current
->mm
);
1745 fill_note(info
->notes
+ 1, "CORE", NT_PRPSINFO
,
1746 sizeof(*info
->psinfo
), info
->psinfo
);
1750 fill_auxv_note(&info
->notes
[info
->numnote
++], current
->mm
);
1752 /* Try to dump the FPU. */
1753 info
->prstatus
->pr_fpvalid
= elf_core_copy_task_fpregs(current
, regs
,
1755 if (info
->prstatus
->pr_fpvalid
)
1756 fill_note(info
->notes
+ info
->numnote
++,
1757 "CORE", NT_PRFPREG
, sizeof(*info
->fpu
), info
->fpu
);
1758 #ifdef ELF_CORE_COPY_XFPREGS
1759 if (elf_core_copy_task_xfpregs(current
, info
->xfpu
))
1760 fill_note(info
->notes
+ info
->numnote
++,
1761 "LINUX", ELF_CORE_XFPREG_TYPE
,
1762 sizeof(*info
->xfpu
), info
->xfpu
);
1768 static size_t get_note_info_size(struct elf_note_info
*info
)
1773 for (i
= 0; i
< info
->numnote
; i
++)
1774 sz
+= notesize(info
->notes
+ i
);
1776 sz
+= info
->thread_status_size
;
1781 static int write_note_info(struct elf_note_info
*info
,
1782 struct file
*file
, loff_t
*foffset
)
1785 struct list_head
*t
;
1787 for (i
= 0; i
< info
->numnote
; i
++)
1788 if (!writenote(info
->notes
+ i
, file
, foffset
))
1791 /* write out the thread status notes section */
1792 list_for_each(t
, &info
->thread_list
) {
1793 struct elf_thread_status
*tmp
=
1794 list_entry(t
, struct elf_thread_status
, list
);
1796 for (i
= 0; i
< tmp
->num_notes
; i
++)
1797 if (!writenote(&tmp
->notes
[i
], file
, foffset
))
1804 static void free_note_info(struct elf_note_info
*info
)
1806 while (!list_empty(&info
->thread_list
)) {
1807 struct list_head
*tmp
= info
->thread_list
.next
;
1809 kfree(list_entry(tmp
, struct elf_thread_status
, list
));
1812 kfree(info
->prstatus
);
1813 kfree(info
->psinfo
);
1816 #ifdef ELF_CORE_COPY_XFPREGS
1823 static struct vm_area_struct
*first_vma(struct task_struct
*tsk
,
1824 struct vm_area_struct
*gate_vma
)
1826 struct vm_area_struct
*ret
= tsk
->mm
->mmap
;
1833 * Helper function for iterating across a vma list. It ensures that the caller
1834 * will visit `gate_vma' prior to terminating the search.
1836 static struct vm_area_struct
*next_vma(struct vm_area_struct
*this_vma
,
1837 struct vm_area_struct
*gate_vma
)
1839 struct vm_area_struct
*ret
;
1841 ret
= this_vma
->vm_next
;
1844 if (this_vma
== gate_vma
)
1849 static void fill_extnum_info(struct elfhdr
*elf
, struct elf_shdr
*shdr4extnum
,
1850 elf_addr_t e_shoff
, int segs
)
1852 elf
->e_shoff
= e_shoff
;
1853 elf
->e_shentsize
= sizeof(*shdr4extnum
);
1855 elf
->e_shstrndx
= SHN_UNDEF
;
1857 memset(shdr4extnum
, 0, sizeof(*shdr4extnum
));
1859 shdr4extnum
->sh_type
= SHT_NULL
;
1860 shdr4extnum
->sh_size
= elf
->e_shnum
;
1861 shdr4extnum
->sh_link
= elf
->e_shstrndx
;
1862 shdr4extnum
->sh_info
= segs
;
1865 static size_t elf_core_vma_data_size(struct vm_area_struct
*gate_vma
,
1866 unsigned long mm_flags
)
1868 struct vm_area_struct
*vma
;
1871 for (vma
= first_vma(current
, gate_vma
); vma
!= NULL
;
1872 vma
= next_vma(vma
, gate_vma
))
1873 size
+= vma_dump_size(vma
, mm_flags
);
1880 * This is a two-pass process; first we find the offsets of the bits,
1881 * and then they are actually written out. If we run out of core limit
1884 static int elf_core_dump(struct coredump_params
*cprm
)
1890 struct vm_area_struct
*vma
, *gate_vma
;
1891 struct elfhdr
*elf
= NULL
;
1892 loff_t offset
= 0, dataoff
, foffset
;
1893 struct elf_note_info info
;
1894 struct elf_phdr
*phdr4note
= NULL
;
1895 struct elf_shdr
*shdr4extnum
= NULL
;
1900 * We no longer stop all VM operations.
1902 * This is because those proceses that could possibly change map_count
1903 * or the mmap / vma pages are now blocked in do_exit on current
1904 * finishing this core dump.
1906 * Only ptrace can touch these memory addresses, but it doesn't change
1907 * the map_count or the pages allocated. So no possibility of crashing
1908 * exists while dumping the mm->vm_next areas to the core file.
1911 /* alloc memory for large data structures: too large to be on stack */
1912 elf
= kmalloc(sizeof(*elf
), GFP_KERNEL
);
1916 * The number of segs are recored into ELF header as 16bit value.
1917 * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
1919 segs
= current
->mm
->map_count
;
1920 segs
+= elf_core_extra_phdrs();
1922 gate_vma
= get_gate_vma(current
->mm
);
1923 if (gate_vma
!= NULL
)
1926 /* for notes section */
1929 /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
1930 * this, kernel supports extended numbering. Have a look at
1931 * include/linux/elf.h for further information. */
1932 e_phnum
= segs
> PN_XNUM
? PN_XNUM
: segs
;
1935 * Collect all the non-memory information about the process for the
1936 * notes. This also sets up the file header.
1938 if (!fill_note_info(elf
, e_phnum
, &info
, cprm
->signr
, cprm
->regs
))
1942 current
->flags
|= PF_DUMPCORE
;
1947 offset
+= sizeof(*elf
); /* Elf header */
1948 offset
+= segs
* sizeof(struct elf_phdr
); /* Program headers */
1951 /* Write notes phdr entry */
1953 size_t sz
= get_note_info_size(&info
);
1955 sz
+= elf_coredump_extra_notes_size();
1957 phdr4note
= kmalloc(sizeof(*phdr4note
), GFP_KERNEL
);
1961 fill_elf_note_phdr(phdr4note
, sz
, offset
);
1965 dataoff
= offset
= roundup(offset
, ELF_EXEC_PAGESIZE
);
1967 offset
+= elf_core_vma_data_size(gate_vma
, cprm
->mm_flags
);
1968 offset
+= elf_core_extra_data_size();
1971 if (e_phnum
== PN_XNUM
) {
1972 shdr4extnum
= kmalloc(sizeof(*shdr4extnum
), GFP_KERNEL
);
1975 fill_extnum_info(elf
, shdr4extnum
, e_shoff
, segs
);
1980 size
+= sizeof(*elf
);
1981 if (size
> cprm
->limit
|| !dump_write(cprm
->file
, elf
, sizeof(*elf
)))
1984 size
+= sizeof(*phdr4note
);
1985 if (size
> cprm
->limit
1986 || !dump_write(cprm
->file
, phdr4note
, sizeof(*phdr4note
)))
1989 /* Write program headers for segments dump */
1990 for (vma
= first_vma(current
, gate_vma
); vma
!= NULL
;
1991 vma
= next_vma(vma
, gate_vma
)) {
1992 struct elf_phdr phdr
;
1994 phdr
.p_type
= PT_LOAD
;
1995 phdr
.p_offset
= offset
;
1996 phdr
.p_vaddr
= vma
->vm_start
;
1998 phdr
.p_filesz
= vma_dump_size(vma
, cprm
->mm_flags
);
1999 phdr
.p_memsz
= vma
->vm_end
- vma
->vm_start
;
2000 offset
+= phdr
.p_filesz
;
2001 phdr
.p_flags
= vma
->vm_flags
& VM_READ
? PF_R
: 0;
2002 if (vma
->vm_flags
& VM_WRITE
)
2003 phdr
.p_flags
|= PF_W
;
2004 if (vma
->vm_flags
& VM_EXEC
)
2005 phdr
.p_flags
|= PF_X
;
2006 phdr
.p_align
= ELF_EXEC_PAGESIZE
;
2008 size
+= sizeof(phdr
);
2009 if (size
> cprm
->limit
2010 || !dump_write(cprm
->file
, &phdr
, sizeof(phdr
)))
2014 if (!elf_core_write_extra_phdrs(cprm
->file
, offset
, &size
, cprm
->limit
))
2017 /* write out the notes section */
2018 if (!write_note_info(&info
, cprm
->file
, &foffset
))
2021 if (elf_coredump_extra_notes_write(cprm
->file
, &foffset
))
2025 if (!dump_seek(cprm
->file
, dataoff
- foffset
))
2028 for (vma
= first_vma(current
, gate_vma
); vma
!= NULL
;
2029 vma
= next_vma(vma
, gate_vma
)) {
2033 end
= vma
->vm_start
+ vma_dump_size(vma
, cprm
->mm_flags
);
2035 for (addr
= vma
->vm_start
; addr
< end
; addr
+= PAGE_SIZE
) {
2039 page
= get_dump_page(addr
);
2041 void *kaddr
= kmap(page
);
2042 stop
= ((size
+= PAGE_SIZE
) > cprm
->limit
) ||
2043 !dump_write(cprm
->file
, kaddr
,
2046 page_cache_release(page
);
2048 stop
= !dump_seek(cprm
->file
, PAGE_SIZE
);
2054 if (!elf_core_write_extra_data(cprm
->file
, &size
, cprm
->limit
))
2057 if (e_phnum
== PN_XNUM
) {
2058 size
+= sizeof(*shdr4extnum
);
2059 if (size
> cprm
->limit
2060 || !dump_write(cprm
->file
, shdr4extnum
,
2061 sizeof(*shdr4extnum
)))
2069 free_note_info(&info
);
2077 #endif /* CONFIG_ELF_CORE */
2079 static int __init
init_elf_binfmt(void)
2081 return register_binfmt(&elf_format
);
2084 static void __exit
exit_elf_binfmt(void)
2086 /* Remove the COFF and ELF loaders. */
2087 unregister_binfmt(&elf_format
);
2090 core_initcall(init_elf_binfmt
);
2091 module_exit(exit_elf_binfmt
);
2092 MODULE_LICENSE("GPL");