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 <asm/uaccess.h>
35 #include <asm/param.h>
38 static int load_elf_binary(struct linux_binprm
*bprm
, struct pt_regs
*regs
);
39 static int load_elf_library(struct file
*);
40 static unsigned long elf_map(struct file
*, unsigned long, struct elf_phdr
*,
41 int, int, unsigned long);
44 * If we don't support core dumping, then supply a NULL so we
47 #ifdef CONFIG_ELF_CORE
48 static int elf_core_dump(long signr
, struct pt_regs
*regs
, struct file
*file
, unsigned long limit
);
50 #define elf_core_dump NULL
53 #if ELF_EXEC_PAGESIZE > PAGE_SIZE
54 #define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
56 #define ELF_MIN_ALIGN PAGE_SIZE
59 #ifndef ELF_CORE_EFLAGS
60 #define ELF_CORE_EFLAGS 0
63 #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
64 #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
65 #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
67 static struct linux_binfmt elf_format
= {
68 .module
= THIS_MODULE
,
69 .load_binary
= load_elf_binary
,
70 .load_shlib
= load_elf_library
,
71 .core_dump
= elf_core_dump
,
72 .min_coredump
= ELF_EXEC_PAGESIZE
,
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
)))
320 static unsigned long elf_map(struct file
*filep
, unsigned long addr
,
321 struct elf_phdr
*eppnt
, int prot
, int type
,
322 unsigned long total_size
)
324 unsigned long map_addr
;
325 unsigned long size
= eppnt
->p_filesz
+ ELF_PAGEOFFSET(eppnt
->p_vaddr
);
326 unsigned long off
= eppnt
->p_offset
- ELF_PAGEOFFSET(eppnt
->p_vaddr
);
327 addr
= ELF_PAGESTART(addr
);
328 size
= ELF_PAGEALIGN(size
);
330 /* mmap() will return -EINVAL if given a zero size, but a
331 * segment with zero filesize is perfectly valid */
335 down_write(¤t
->mm
->mmap_sem
);
337 * total_size is the size of the ELF (interpreter) image.
338 * The _first_ mmap needs to know the full size, otherwise
339 * randomization might put this image into an overlapping
340 * position with the ELF binary image. (since size < total_size)
341 * So we first map the 'big' image - and unmap the remainder at
342 * the end. (which unmap is needed for ELF images with holes.)
345 total_size
= ELF_PAGEALIGN(total_size
);
346 map_addr
= do_mmap(filep
, addr
, total_size
, prot
, type
, off
);
347 if (!BAD_ADDR(map_addr
))
348 do_munmap(current
->mm
, map_addr
+size
, total_size
-size
);
350 map_addr
= do_mmap(filep
, addr
, size
, prot
, type
, off
);
352 up_write(¤t
->mm
->mmap_sem
);
356 #endif /* !elf_map */
358 static unsigned long total_mapping_size(struct elf_phdr
*cmds
, int nr
)
360 int i
, first_idx
= -1, last_idx
= -1;
362 for (i
= 0; i
< nr
; i
++) {
363 if (cmds
[i
].p_type
== PT_LOAD
) {
372 return cmds
[last_idx
].p_vaddr
+ cmds
[last_idx
].p_memsz
-
373 ELF_PAGESTART(cmds
[first_idx
].p_vaddr
);
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
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
)
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
;
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
)
399 if (!elf_check_arch(interp_elf_ex
))
401 if (!interpreter
->f_op
|| !interpreter
->f_op
->mmap
)
405 * If the size of this structure has changed, then punt, since
406 * we will be doing the wrong thing.
408 if (interp_elf_ex
->e_phentsize
!= sizeof(struct elf_phdr
))
410 if (interp_elf_ex
->e_phnum
< 1 ||
411 interp_elf_ex
->e_phnum
> 65536U / sizeof(struct elf_phdr
))
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
)
418 elf_phdata
= kmalloc(size
, GFP_KERNEL
);
422 retval
= kernel_read(interpreter
, interp_elf_ex
->e_phoff
,
423 (char *)elf_phdata
,size
);
425 if (retval
!= size
) {
431 total_size
= total_mapping_size(elf_phdata
, interp_elf_ex
->e_phnum
);
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
;
442 unsigned long vaddr
= 0;
443 unsigned long k
, map_addr
;
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
)
457 map_addr
= elf_map(interpreter
, load_addr
+ vaddr
,
458 eppnt
, elf_prot
, elf_type
, total_size
);
460 if (!*interp_map_addr
)
461 *interp_map_addr
= map_addr
;
463 if (BAD_ADDR(map_addr
))
466 if (!load_addr_set
&&
467 interp_elf_ex
->e_type
== ET_DYN
) {
468 load_addr
= map_addr
- ELF_PAGESTART(vaddr
);
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.
477 k
= load_addr
+ eppnt
->p_vaddr
;
479 eppnt
->p_filesz
> eppnt
->p_memsz
||
480 eppnt
->p_memsz
> TASK_SIZE
||
481 TASK_SIZE
- eppnt
->p_memsz
< k
) {
487 * Find the end of the file mapping for this phdr, and
488 * keep track of the largest address we see for this.
490 k
= load_addr
+ eppnt
->p_vaddr
+ eppnt
->p_filesz
;
495 * Do the same thing for the memory mapping - between
496 * elf_bss and last_bss is the bss section.
498 k
= load_addr
+ eppnt
->p_memsz
+ eppnt
->p_vaddr
;
504 if (last_bss
> elf_bss
) {
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
511 if (padzero(elf_bss
)) {
516 /* What we have mapped so far */
517 elf_bss
= ELF_PAGESTART(elf_bss
+ ELF_MIN_ALIGN
- 1);
519 /* Map the last of the bss segment */
520 down_write(¤t
->mm
->mmap_sem
);
521 error
= do_brk(elf_bss
, last_bss
- elf_bss
);
522 up_write(¤t
->mm
->mmap_sem
);
536 * These are the functions used to load ELF style executables and shared
537 * libraries. There is no binary dependent code anywhere else.
540 #define INTERPRETER_NONE 0
541 #define INTERPRETER_ELF 2
543 #ifndef STACK_RND_MASK
544 #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) /* 8MB of VA */
547 static unsigned long randomize_stack_top(unsigned long stack_top
)
549 unsigned int random_variable
= 0;
551 if ((current
->flags
& PF_RANDOMIZE
) &&
552 !(current
->personality
& ADDR_NO_RANDOMIZE
)) {
553 random_variable
= get_random_int() & STACK_RND_MASK
;
554 random_variable
<<= PAGE_SHIFT
;
556 #ifdef CONFIG_STACK_GROWSUP
557 return PAGE_ALIGN(stack_top
) + random_variable
;
559 return PAGE_ALIGN(stack_top
) - random_variable
;
563 static int load_elf_binary(struct linux_binprm
*bprm
, struct pt_regs
*regs
)
565 struct file
*interpreter
= NULL
; /* to shut gcc up */
566 unsigned long load_addr
= 0, load_bias
= 0;
567 int load_addr_set
= 0;
568 char * elf_interpreter
= NULL
;
570 struct elf_phdr
*elf_ppnt
, *elf_phdata
;
571 unsigned long elf_bss
, elf_brk
;
574 unsigned long elf_entry
;
575 unsigned long interp_load_addr
= 0;
576 unsigned long start_code
, end_code
, start_data
, end_data
;
577 unsigned long reloc_func_desc
= 0;
578 int executable_stack
= EXSTACK_DEFAULT
;
579 unsigned long def_flags
= 0;
581 struct elfhdr elf_ex
;
582 struct elfhdr interp_elf_ex
;
585 loc
= kmalloc(sizeof(*loc
), GFP_KERNEL
);
591 /* Get the exec-header */
592 loc
->elf_ex
= *((struct elfhdr
*)bprm
->buf
);
595 /* First of all, some simple consistency checks */
596 if (memcmp(loc
->elf_ex
.e_ident
, ELFMAG
, SELFMAG
) != 0)
599 if (loc
->elf_ex
.e_type
!= ET_EXEC
&& loc
->elf_ex
.e_type
!= ET_DYN
)
601 if (!elf_check_arch(&loc
->elf_ex
))
603 if (!bprm
->file
->f_op
||!bprm
->file
->f_op
->mmap
)
606 /* Now read in all of the header information */
607 if (loc
->elf_ex
.e_phentsize
!= sizeof(struct elf_phdr
))
609 if (loc
->elf_ex
.e_phnum
< 1 ||
610 loc
->elf_ex
.e_phnum
> 65536U / sizeof(struct elf_phdr
))
612 size
= loc
->elf_ex
.e_phnum
* sizeof(struct elf_phdr
);
614 elf_phdata
= kmalloc(size
, GFP_KERNEL
);
618 retval
= kernel_read(bprm
->file
, loc
->elf_ex
.e_phoff
,
619 (char *)elf_phdata
, size
);
620 if (retval
!= size
) {
626 elf_ppnt
= elf_phdata
;
635 for (i
= 0; i
< loc
->elf_ex
.e_phnum
; i
++) {
636 if (elf_ppnt
->p_type
== PT_INTERP
) {
637 /* This is the program interpreter used for
638 * shared libraries - for now assume that this
639 * is an a.out format binary
642 if (elf_ppnt
->p_filesz
> PATH_MAX
||
643 elf_ppnt
->p_filesz
< 2)
647 elf_interpreter
= kmalloc(elf_ppnt
->p_filesz
,
649 if (!elf_interpreter
)
652 retval
= kernel_read(bprm
->file
, elf_ppnt
->p_offset
,
655 if (retval
!= elf_ppnt
->p_filesz
) {
658 goto out_free_interp
;
660 /* make sure path is NULL terminated */
662 if (elf_interpreter
[elf_ppnt
->p_filesz
- 1] != '\0')
663 goto out_free_interp
;
666 * The early SET_PERSONALITY here is so that the lookup
667 * for the interpreter happens in the namespace of the
668 * to-be-execed image. SET_PERSONALITY can select an
671 * However, SET_PERSONALITY is NOT allowed to switch
672 * this task into the new images's memory mapping
673 * policy - that is, TASK_SIZE must still evaluate to
674 * that which is appropriate to the execing application.
675 * This is because exit_mmap() needs to have TASK_SIZE
676 * evaluate to the size of the old image.
678 * So if (say) a 64-bit application is execing a 32-bit
679 * application it is the architecture's responsibility
680 * to defer changing the value of TASK_SIZE until the
681 * switch really is going to happen - do this in
682 * flush_thread(). - akpm
684 SET_PERSONALITY(loc
->elf_ex
);
686 interpreter
= open_exec(elf_interpreter
);
687 retval
= PTR_ERR(interpreter
);
688 if (IS_ERR(interpreter
))
689 goto out_free_interp
;
692 * If the binary is not readable then enforce
693 * mm->dumpable = 0 regardless of the interpreter's
696 if (file_permission(interpreter
, MAY_READ
) < 0)
697 bprm
->interp_flags
|= BINPRM_FLAGS_ENFORCE_NONDUMP
;
699 retval
= kernel_read(interpreter
, 0, bprm
->buf
,
701 if (retval
!= BINPRM_BUF_SIZE
) {
704 goto out_free_dentry
;
707 /* Get the exec headers */
708 loc
->interp_elf_ex
= *((struct elfhdr
*)bprm
->buf
);
714 elf_ppnt
= elf_phdata
;
715 for (i
= 0; i
< loc
->elf_ex
.e_phnum
; i
++, elf_ppnt
++)
716 if (elf_ppnt
->p_type
== PT_GNU_STACK
) {
717 if (elf_ppnt
->p_flags
& PF_X
)
718 executable_stack
= EXSTACK_ENABLE_X
;
720 executable_stack
= EXSTACK_DISABLE_X
;
724 /* Some simple consistency checks for the interpreter */
725 if (elf_interpreter
) {
727 /* Not an ELF interpreter */
728 if (memcmp(loc
->interp_elf_ex
.e_ident
, ELFMAG
, SELFMAG
) != 0)
729 goto out_free_dentry
;
730 /* Verify the interpreter has a valid arch */
731 if (!elf_check_arch(&loc
->interp_elf_ex
))
732 goto out_free_dentry
;
734 /* Executables without an interpreter also need a personality */
735 SET_PERSONALITY(loc
->elf_ex
);
738 /* Flush all traces of the currently running executable */
739 retval
= flush_old_exec(bprm
);
741 goto out_free_dentry
;
743 /* OK, This is the point of no return */
744 current
->flags
&= ~PF_FORKNOEXEC
;
745 current
->mm
->def_flags
= def_flags
;
747 /* Do this immediately, since STACK_TOP as used in setup_arg_pages
748 may depend on the personality. */
749 SET_PERSONALITY(loc
->elf_ex
);
750 if (elf_read_implies_exec(loc
->elf_ex
, executable_stack
))
751 current
->personality
|= READ_IMPLIES_EXEC
;
753 if (!(current
->personality
& ADDR_NO_RANDOMIZE
) && randomize_va_space
)
754 current
->flags
|= PF_RANDOMIZE
;
755 arch_pick_mmap_layout(current
->mm
);
757 /* Do this so that we can load the interpreter, if need be. We will
758 change some of these later */
759 current
->mm
->free_area_cache
= current
->mm
->mmap_base
;
760 current
->mm
->cached_hole_size
= 0;
761 retval
= setup_arg_pages(bprm
, randomize_stack_top(STACK_TOP
),
764 send_sig(SIGKILL
, current
, 0);
765 goto out_free_dentry
;
768 current
->mm
->start_stack
= bprm
->p
;
770 /* Now we do a little grungy work by mmaping the ELF image into
771 the correct location in memory. */
772 for(i
= 0, elf_ppnt
= elf_phdata
;
773 i
< loc
->elf_ex
.e_phnum
; i
++, elf_ppnt
++) {
774 int elf_prot
= 0, elf_flags
;
775 unsigned long k
, vaddr
;
777 if (elf_ppnt
->p_type
!= PT_LOAD
)
780 if (unlikely (elf_brk
> elf_bss
)) {
783 /* There was a PT_LOAD segment with p_memsz > p_filesz
784 before this one. Map anonymous pages, if needed,
785 and clear the area. */
786 retval
= set_brk (elf_bss
+ load_bias
,
787 elf_brk
+ load_bias
);
789 send_sig(SIGKILL
, current
, 0);
790 goto out_free_dentry
;
792 nbyte
= ELF_PAGEOFFSET(elf_bss
);
794 nbyte
= ELF_MIN_ALIGN
- nbyte
;
795 if (nbyte
> elf_brk
- elf_bss
)
796 nbyte
= elf_brk
- elf_bss
;
797 if (clear_user((void __user
*)elf_bss
+
800 * This bss-zeroing can fail if the ELF
801 * file specifies odd protections. So
802 * we don't check the return value
808 if (elf_ppnt
->p_flags
& PF_R
)
809 elf_prot
|= PROT_READ
;
810 if (elf_ppnt
->p_flags
& PF_W
)
811 elf_prot
|= PROT_WRITE
;
812 if (elf_ppnt
->p_flags
& PF_X
)
813 elf_prot
|= PROT_EXEC
;
815 elf_flags
= MAP_PRIVATE
| MAP_DENYWRITE
| MAP_EXECUTABLE
;
817 vaddr
= elf_ppnt
->p_vaddr
;
818 if (loc
->elf_ex
.e_type
== ET_EXEC
|| load_addr_set
) {
819 elf_flags
|= MAP_FIXED
;
820 } else if (loc
->elf_ex
.e_type
== ET_DYN
) {
821 /* Try and get dynamic programs out of the way of the
822 * default mmap base, as well as whatever program they
823 * might try to exec. This is because the brk will
824 * follow the loader, and is not movable. */
828 load_bias
= ELF_PAGESTART(ELF_ET_DYN_BASE
- vaddr
);
832 error
= elf_map(bprm
->file
, load_bias
+ vaddr
, elf_ppnt
,
833 elf_prot
, elf_flags
, 0);
834 if (BAD_ADDR(error
)) {
835 send_sig(SIGKILL
, current
, 0);
836 retval
= IS_ERR((void *)error
) ?
837 PTR_ERR((void*)error
) : -EINVAL
;
838 goto out_free_dentry
;
841 if (!load_addr_set
) {
843 load_addr
= (elf_ppnt
->p_vaddr
- elf_ppnt
->p_offset
);
844 if (loc
->elf_ex
.e_type
== ET_DYN
) {
846 ELF_PAGESTART(load_bias
+ vaddr
);
847 load_addr
+= load_bias
;
848 reloc_func_desc
= load_bias
;
851 k
= elf_ppnt
->p_vaddr
;
858 * Check to see if the section's size will overflow the
859 * allowed task size. Note that p_filesz must always be
860 * <= p_memsz so it is only necessary to check p_memsz.
862 if (BAD_ADDR(k
) || elf_ppnt
->p_filesz
> elf_ppnt
->p_memsz
||
863 elf_ppnt
->p_memsz
> TASK_SIZE
||
864 TASK_SIZE
- elf_ppnt
->p_memsz
< k
) {
865 /* set_brk can never work. Avoid overflows. */
866 send_sig(SIGKILL
, current
, 0);
868 goto out_free_dentry
;
871 k
= elf_ppnt
->p_vaddr
+ elf_ppnt
->p_filesz
;
875 if ((elf_ppnt
->p_flags
& PF_X
) && end_code
< k
)
879 k
= elf_ppnt
->p_vaddr
+ elf_ppnt
->p_memsz
;
884 loc
->elf_ex
.e_entry
+= load_bias
;
885 elf_bss
+= load_bias
;
886 elf_brk
+= load_bias
;
887 start_code
+= load_bias
;
888 end_code
+= load_bias
;
889 start_data
+= load_bias
;
890 end_data
+= load_bias
;
892 /* Calling set_brk effectively mmaps the pages that we need
893 * for the bss and break sections. We must do this before
894 * mapping in the interpreter, to make sure it doesn't wind
895 * up getting placed where the bss needs to go.
897 retval
= set_brk(elf_bss
, elf_brk
);
899 send_sig(SIGKILL
, current
, 0);
900 goto out_free_dentry
;
902 if (likely(elf_bss
!= elf_brk
) && unlikely(padzero(elf_bss
))) {
903 send_sig(SIGSEGV
, current
, 0);
904 retval
= -EFAULT
; /* Nobody gets to see this, but.. */
905 goto out_free_dentry
;
908 if (elf_interpreter
) {
909 unsigned long uninitialized_var(interp_map_addr
);
911 elf_entry
= load_elf_interp(&loc
->interp_elf_ex
,
915 if (!IS_ERR((void *)elf_entry
)) {
917 * load_elf_interp() returns relocation
920 interp_load_addr
= elf_entry
;
921 elf_entry
+= loc
->interp_elf_ex
.e_entry
;
923 if (BAD_ADDR(elf_entry
)) {
924 force_sig(SIGSEGV
, current
);
925 retval
= IS_ERR((void *)elf_entry
) ?
926 (int)elf_entry
: -EINVAL
;
927 goto out_free_dentry
;
929 reloc_func_desc
= interp_load_addr
;
931 allow_write_access(interpreter
);
933 kfree(elf_interpreter
);
935 elf_entry
= loc
->elf_ex
.e_entry
;
936 if (BAD_ADDR(elf_entry
)) {
937 force_sig(SIGSEGV
, current
);
939 goto out_free_dentry
;
945 set_binfmt(&elf_format
);
947 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
948 retval
= arch_setup_additional_pages(bprm
, !!elf_interpreter
);
950 send_sig(SIGKILL
, current
, 0);
953 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
955 install_exec_creds(bprm
);
956 current
->flags
&= ~PF_FORKNOEXEC
;
957 retval
= create_elf_tables(bprm
, &loc
->elf_ex
,
958 load_addr
, interp_load_addr
);
960 send_sig(SIGKILL
, current
, 0);
963 /* N.B. passed_fileno might not be initialized? */
964 current
->mm
->end_code
= end_code
;
965 current
->mm
->start_code
= start_code
;
966 current
->mm
->start_data
= start_data
;
967 current
->mm
->end_data
= end_data
;
968 current
->mm
->start_stack
= bprm
->p
;
970 #ifdef arch_randomize_brk
971 if ((current
->flags
& PF_RANDOMIZE
) && (randomize_va_space
> 1))
972 current
->mm
->brk
= current
->mm
->start_brk
=
973 arch_randomize_brk(current
->mm
);
976 if (current
->personality
& MMAP_PAGE_ZERO
) {
977 /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
978 and some applications "depend" upon this behavior.
979 Since we do not have the power to recompile these, we
980 emulate the SVr4 behavior. Sigh. */
981 down_write(¤t
->mm
->mmap_sem
);
982 error
= do_mmap(NULL
, 0, PAGE_SIZE
, PROT_READ
| PROT_EXEC
,
983 MAP_FIXED
| MAP_PRIVATE
, 0);
984 up_write(¤t
->mm
->mmap_sem
);
989 * The ABI may specify that certain registers be set up in special
990 * ways (on i386 %edx is the address of a DT_FINI function, for
991 * example. In addition, it may also specify (eg, PowerPC64 ELF)
992 * that the e_entry field is the address of the function descriptor
993 * for the startup routine, rather than the address of the startup
994 * routine itself. This macro performs whatever initialization to
995 * the regs structure is required as well as any relocations to the
996 * function descriptor entries when executing dynamically links apps.
998 ELF_PLAT_INIT(regs
, reloc_func_desc
);
1001 start_thread(regs
, elf_entry
, bprm
->p
);
1010 allow_write_access(interpreter
);
1014 kfree(elf_interpreter
);
1020 /* This is really simpleminded and specialized - we are loading an
1021 a.out library that is given an ELF header. */
1022 static int load_elf_library(struct file
*file
)
1024 struct elf_phdr
*elf_phdata
;
1025 struct elf_phdr
*eppnt
;
1026 unsigned long elf_bss
, bss
, len
;
1027 int retval
, error
, i
, j
;
1028 struct elfhdr elf_ex
;
1031 retval
= kernel_read(file
, 0, (char *)&elf_ex
, sizeof(elf_ex
));
1032 if (retval
!= sizeof(elf_ex
))
1035 if (memcmp(elf_ex
.e_ident
, ELFMAG
, SELFMAG
) != 0)
1038 /* First of all, some simple consistency checks */
1039 if (elf_ex
.e_type
!= ET_EXEC
|| elf_ex
.e_phnum
> 2 ||
1040 !elf_check_arch(&elf_ex
) || !file
->f_op
|| !file
->f_op
->mmap
)
1043 /* Now read in all of the header information */
1045 j
= sizeof(struct elf_phdr
) * elf_ex
.e_phnum
;
1046 /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
1049 elf_phdata
= kmalloc(j
, GFP_KERNEL
);
1055 retval
= kernel_read(file
, elf_ex
.e_phoff
, (char *)eppnt
, j
);
1059 for (j
= 0, i
= 0; i
<elf_ex
.e_phnum
; i
++)
1060 if ((eppnt
+ i
)->p_type
== PT_LOAD
)
1065 while (eppnt
->p_type
!= PT_LOAD
)
1068 /* Now use mmap to map the library into memory. */
1069 down_write(¤t
->mm
->mmap_sem
);
1070 error
= do_mmap(file
,
1071 ELF_PAGESTART(eppnt
->p_vaddr
),
1073 ELF_PAGEOFFSET(eppnt
->p_vaddr
)),
1074 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
1075 MAP_FIXED
| MAP_PRIVATE
| MAP_DENYWRITE
,
1077 ELF_PAGEOFFSET(eppnt
->p_vaddr
)));
1078 up_write(¤t
->mm
->mmap_sem
);
1079 if (error
!= ELF_PAGESTART(eppnt
->p_vaddr
))
1082 elf_bss
= eppnt
->p_vaddr
+ eppnt
->p_filesz
;
1083 if (padzero(elf_bss
)) {
1088 len
= ELF_PAGESTART(eppnt
->p_filesz
+ eppnt
->p_vaddr
+
1090 bss
= eppnt
->p_memsz
+ eppnt
->p_vaddr
;
1092 down_write(¤t
->mm
->mmap_sem
);
1093 do_brk(len
, bss
- len
);
1094 up_write(¤t
->mm
->mmap_sem
);
1104 #ifdef CONFIG_ELF_CORE
1108 * Modelled on fs/exec.c:aout_core_dump()
1109 * Jeremy Fitzhardinge <jeremy@sw.oz.au>
1112 * These are the only things you should do on a core-file: use only these
1113 * functions to write out all the necessary info.
1115 static int dump_write(struct file
*file
, const void *addr
, int nr
)
1117 return file
->f_op
->write(file
, addr
, nr
, &file
->f_pos
) == nr
;
1120 static int dump_seek(struct file
*file
, loff_t off
)
1122 if (file
->f_op
->llseek
&& file
->f_op
->llseek
!= no_llseek
) {
1123 if (file
->f_op
->llseek(file
, off
, SEEK_CUR
) < 0)
1126 char *buf
= (char *)get_zeroed_page(GFP_KERNEL
);
1130 unsigned long n
= off
;
1133 if (!dump_write(file
, buf
, n
))
1137 free_page((unsigned long)buf
);
1143 * Decide what to dump of a segment, part, all or none.
1145 static unsigned long vma_dump_size(struct vm_area_struct
*vma
,
1146 unsigned long mm_flags
)
1148 #define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
1150 /* The vma can be set up to tell us the answer directly. */
1151 if (vma
->vm_flags
& VM_ALWAYSDUMP
)
1154 /* Hugetlb memory check */
1155 if (vma
->vm_flags
& VM_HUGETLB
) {
1156 if ((vma
->vm_flags
& VM_SHARED
) && FILTER(HUGETLB_SHARED
))
1158 if (!(vma
->vm_flags
& VM_SHARED
) && FILTER(HUGETLB_PRIVATE
))
1162 /* Do not dump I/O mapped devices or special mappings */
1163 if (vma
->vm_flags
& (VM_IO
| VM_RESERVED
))
1166 /* By default, dump shared memory if mapped from an anonymous file. */
1167 if (vma
->vm_flags
& VM_SHARED
) {
1168 if (vma
->vm_file
->f_path
.dentry
->d_inode
->i_nlink
== 0 ?
1169 FILTER(ANON_SHARED
) : FILTER(MAPPED_SHARED
))
1174 /* Dump segments that have been written to. */
1175 if (vma
->anon_vma
&& FILTER(ANON_PRIVATE
))
1177 if (vma
->vm_file
== NULL
)
1180 if (FILTER(MAPPED_PRIVATE
))
1184 * If this looks like the beginning of a DSO or executable mapping,
1185 * check for an ELF header. If we find one, dump the first page to
1186 * aid in determining what was mapped here.
1188 if (FILTER(ELF_HEADERS
) &&
1189 vma
->vm_pgoff
== 0 && (vma
->vm_flags
& VM_READ
)) {
1190 u32 __user
*header
= (u32 __user
*) vma
->vm_start
;
1192 mm_segment_t fs
= get_fs();
1194 * Doing it this way gets the constant folded by GCC.
1198 char elfmag
[SELFMAG
];
1200 BUILD_BUG_ON(SELFMAG
!= sizeof word
);
1201 magic
.elfmag
[EI_MAG0
] = ELFMAG0
;
1202 magic
.elfmag
[EI_MAG1
] = ELFMAG1
;
1203 magic
.elfmag
[EI_MAG2
] = ELFMAG2
;
1204 magic
.elfmag
[EI_MAG3
] = ELFMAG3
;
1206 * Switch to the user "segment" for get_user(),
1207 * then put back what elf_core_dump() had in place.
1210 if (unlikely(get_user(word
, header
)))
1213 if (word
== magic
.cmp
)
1222 return vma
->vm_end
- vma
->vm_start
;
1225 /* An ELF note in memory */
1230 unsigned int datasz
;
1234 static int notesize(struct memelfnote
*en
)
1238 sz
= sizeof(struct elf_note
);
1239 sz
+= roundup(strlen(en
->name
) + 1, 4);
1240 sz
+= roundup(en
->datasz
, 4);
1245 #define DUMP_WRITE(addr, nr, foffset) \
1246 do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
1248 static int alignfile(struct file
*file
, loff_t
*foffset
)
1250 static const char buf
[4] = { 0, };
1251 DUMP_WRITE(buf
, roundup(*foffset
, 4) - *foffset
, foffset
);
1255 static int writenote(struct memelfnote
*men
, struct file
*file
,
1259 en
.n_namesz
= strlen(men
->name
) + 1;
1260 en
.n_descsz
= men
->datasz
;
1261 en
.n_type
= men
->type
;
1263 DUMP_WRITE(&en
, sizeof(en
), foffset
);
1264 DUMP_WRITE(men
->name
, en
.n_namesz
, foffset
);
1265 if (!alignfile(file
, foffset
))
1267 DUMP_WRITE(men
->data
, men
->datasz
, foffset
);
1268 if (!alignfile(file
, foffset
))
1275 #define DUMP_WRITE(addr, nr) \
1276 if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
1279 static void fill_elf_header(struct elfhdr
*elf
, int segs
,
1280 u16 machine
, u32 flags
, u8 osabi
)
1282 memset(elf
, 0, sizeof(*elf
));
1284 memcpy(elf
->e_ident
, ELFMAG
, SELFMAG
);
1285 elf
->e_ident
[EI_CLASS
] = ELF_CLASS
;
1286 elf
->e_ident
[EI_DATA
] = ELF_DATA
;
1287 elf
->e_ident
[EI_VERSION
] = EV_CURRENT
;
1288 elf
->e_ident
[EI_OSABI
] = ELF_OSABI
;
1290 elf
->e_type
= ET_CORE
;
1291 elf
->e_machine
= machine
;
1292 elf
->e_version
= EV_CURRENT
;
1293 elf
->e_phoff
= sizeof(struct elfhdr
);
1294 elf
->e_flags
= flags
;
1295 elf
->e_ehsize
= sizeof(struct elfhdr
);
1296 elf
->e_phentsize
= sizeof(struct elf_phdr
);
1297 elf
->e_phnum
= segs
;
1302 static void fill_elf_note_phdr(struct elf_phdr
*phdr
, int sz
, loff_t offset
)
1304 phdr
->p_type
= PT_NOTE
;
1305 phdr
->p_offset
= offset
;
1308 phdr
->p_filesz
= sz
;
1315 static void fill_note(struct memelfnote
*note
, const char *name
, int type
,
1316 unsigned int sz
, void *data
)
1326 * fill up all the fields in prstatus from the given task struct, except
1327 * registers which need to be filled up separately.
1329 static void fill_prstatus(struct elf_prstatus
*prstatus
,
1330 struct task_struct
*p
, long signr
)
1332 prstatus
->pr_info
.si_signo
= prstatus
->pr_cursig
= signr
;
1333 prstatus
->pr_sigpend
= p
->pending
.signal
.sig
[0];
1334 prstatus
->pr_sighold
= p
->blocked
.sig
[0];
1336 prstatus
->pr_ppid
= task_pid_vnr(rcu_dereference(p
->real_parent
));
1338 prstatus
->pr_pid
= task_pid_vnr(p
);
1339 prstatus
->pr_pgrp
= task_pgrp_vnr(p
);
1340 prstatus
->pr_sid
= task_session_vnr(p
);
1341 if (thread_group_leader(p
)) {
1342 struct task_cputime cputime
;
1345 * This is the record for the group leader. It shows the
1346 * group-wide total, not its individual thread total.
1348 thread_group_cputime(p
, &cputime
);
1349 cputime_to_timeval(cputime
.utime
, &prstatus
->pr_utime
);
1350 cputime_to_timeval(cputime
.stime
, &prstatus
->pr_stime
);
1352 cputime_to_timeval(p
->utime
, &prstatus
->pr_utime
);
1353 cputime_to_timeval(p
->stime
, &prstatus
->pr_stime
);
1355 cputime_to_timeval(p
->signal
->cutime
, &prstatus
->pr_cutime
);
1356 cputime_to_timeval(p
->signal
->cstime
, &prstatus
->pr_cstime
);
1359 static int fill_psinfo(struct elf_prpsinfo
*psinfo
, struct task_struct
*p
,
1360 struct mm_struct
*mm
)
1362 const struct cred
*cred
;
1363 unsigned int i
, len
;
1365 /* first copy the parameters from user space */
1366 memset(psinfo
, 0, sizeof(struct elf_prpsinfo
));
1368 len
= mm
->arg_end
- mm
->arg_start
;
1369 if (len
>= ELF_PRARGSZ
)
1370 len
= ELF_PRARGSZ
-1;
1371 if (copy_from_user(&psinfo
->pr_psargs
,
1372 (const char __user
*)mm
->arg_start
, len
))
1374 for(i
= 0; i
< len
; i
++)
1375 if (psinfo
->pr_psargs
[i
] == 0)
1376 psinfo
->pr_psargs
[i
] = ' ';
1377 psinfo
->pr_psargs
[len
] = 0;
1380 psinfo
->pr_ppid
= task_pid_vnr(rcu_dereference(p
->real_parent
));
1382 psinfo
->pr_pid
= task_pid_vnr(p
);
1383 psinfo
->pr_pgrp
= task_pgrp_vnr(p
);
1384 psinfo
->pr_sid
= task_session_vnr(p
);
1386 i
= p
->state
? ffz(~p
->state
) + 1 : 0;
1387 psinfo
->pr_state
= i
;
1388 psinfo
->pr_sname
= (i
> 5) ? '.' : "RSDTZW"[i
];
1389 psinfo
->pr_zomb
= psinfo
->pr_sname
== 'Z';
1390 psinfo
->pr_nice
= task_nice(p
);
1391 psinfo
->pr_flag
= p
->flags
;
1393 cred
= __task_cred(p
);
1394 SET_UID(psinfo
->pr_uid
, cred
->uid
);
1395 SET_GID(psinfo
->pr_gid
, cred
->gid
);
1397 strncpy(psinfo
->pr_fname
, p
->comm
, sizeof(psinfo
->pr_fname
));
1402 static void fill_auxv_note(struct memelfnote
*note
, struct mm_struct
*mm
)
1404 elf_addr_t
*auxv
= (elf_addr_t
*) mm
->saved_auxv
;
1408 while (auxv
[i
- 2] != AT_NULL
);
1409 fill_note(note
, "CORE", NT_AUXV
, i
* sizeof(elf_addr_t
), auxv
);
1412 #ifdef CORE_DUMP_USE_REGSET
1413 #include <linux/regset.h>
1415 struct elf_thread_core_info
{
1416 struct elf_thread_core_info
*next
;
1417 struct task_struct
*task
;
1418 struct elf_prstatus prstatus
;
1419 struct memelfnote notes
[0];
1422 struct elf_note_info
{
1423 struct elf_thread_core_info
*thread
;
1424 struct memelfnote psinfo
;
1425 struct memelfnote auxv
;
1431 * When a regset has a writeback hook, we call it on each thread before
1432 * dumping user memory. On register window machines, this makes sure the
1433 * user memory backing the register data is up to date before we read it.
1435 static void do_thread_regset_writeback(struct task_struct
*task
,
1436 const struct user_regset
*regset
)
1438 if (regset
->writeback
)
1439 regset
->writeback(task
, regset
, 1);
1442 static int fill_thread_core_info(struct elf_thread_core_info
*t
,
1443 const struct user_regset_view
*view
,
1444 long signr
, size_t *total
)
1449 * NT_PRSTATUS is the one special case, because the regset data
1450 * goes into the pr_reg field inside the note contents, rather
1451 * than being the whole note contents. We fill the reset in here.
1452 * We assume that regset 0 is NT_PRSTATUS.
1454 fill_prstatus(&t
->prstatus
, t
->task
, signr
);
1455 (void) view
->regsets
[0].get(t
->task
, &view
->regsets
[0],
1456 0, sizeof(t
->prstatus
.pr_reg
),
1457 &t
->prstatus
.pr_reg
, NULL
);
1459 fill_note(&t
->notes
[0], "CORE", NT_PRSTATUS
,
1460 sizeof(t
->prstatus
), &t
->prstatus
);
1461 *total
+= notesize(&t
->notes
[0]);
1463 do_thread_regset_writeback(t
->task
, &view
->regsets
[0]);
1466 * Each other regset might generate a note too. For each regset
1467 * that has no core_note_type or is inactive, we leave t->notes[i]
1468 * all zero and we'll know to skip writing it later.
1470 for (i
= 1; i
< view
->n
; ++i
) {
1471 const struct user_regset
*regset
= &view
->regsets
[i
];
1472 do_thread_regset_writeback(t
->task
, regset
);
1473 if (regset
->core_note_type
&&
1474 (!regset
->active
|| regset
->active(t
->task
, regset
))) {
1476 size_t size
= regset
->n
* regset
->size
;
1477 void *data
= kmalloc(size
, GFP_KERNEL
);
1478 if (unlikely(!data
))
1480 ret
= regset
->get(t
->task
, regset
,
1481 0, size
, data
, NULL
);
1485 if (regset
->core_note_type
!= NT_PRFPREG
)
1486 fill_note(&t
->notes
[i
], "LINUX",
1487 regset
->core_note_type
,
1490 t
->prstatus
.pr_fpvalid
= 1;
1491 fill_note(&t
->notes
[i
], "CORE",
1492 NT_PRFPREG
, size
, data
);
1494 *total
+= notesize(&t
->notes
[i
]);
1502 static int fill_note_info(struct elfhdr
*elf
, int phdrs
,
1503 struct elf_note_info
*info
,
1504 long signr
, struct pt_regs
*regs
)
1506 struct task_struct
*dump_task
= current
;
1507 const struct user_regset_view
*view
= task_user_regset_view(dump_task
);
1508 struct elf_thread_core_info
*t
;
1509 struct elf_prpsinfo
*psinfo
;
1510 struct core_thread
*ct
;
1514 info
->thread
= NULL
;
1516 psinfo
= kmalloc(sizeof(*psinfo
), GFP_KERNEL
);
1520 fill_note(&info
->psinfo
, "CORE", NT_PRPSINFO
, sizeof(*psinfo
), psinfo
);
1523 * Figure out how many notes we're going to need for each thread.
1525 info
->thread_notes
= 0;
1526 for (i
= 0; i
< view
->n
; ++i
)
1527 if (view
->regsets
[i
].core_note_type
!= 0)
1528 ++info
->thread_notes
;
1531 * Sanity check. We rely on regset 0 being in NT_PRSTATUS,
1532 * since it is our one special case.
1534 if (unlikely(info
->thread_notes
== 0) ||
1535 unlikely(view
->regsets
[0].core_note_type
!= NT_PRSTATUS
)) {
1541 * Initialize the ELF file header.
1543 fill_elf_header(elf
, phdrs
,
1544 view
->e_machine
, view
->e_flags
, view
->ei_osabi
);
1547 * Allocate a structure for each thread.
1549 for (ct
= &dump_task
->mm
->core_state
->dumper
; ct
; ct
= ct
->next
) {
1550 t
= kzalloc(offsetof(struct elf_thread_core_info
,
1551 notes
[info
->thread_notes
]),
1557 if (ct
->task
== dump_task
|| !info
->thread
) {
1558 t
->next
= info
->thread
;
1562 * Make sure to keep the original task at
1563 * the head of the list.
1565 t
->next
= info
->thread
->next
;
1566 info
->thread
->next
= t
;
1571 * Now fill in each thread's information.
1573 for (t
= info
->thread
; t
!= NULL
; t
= t
->next
)
1574 if (!fill_thread_core_info(t
, view
, signr
, &info
->size
))
1578 * Fill in the two process-wide notes.
1580 fill_psinfo(psinfo
, dump_task
->group_leader
, dump_task
->mm
);
1581 info
->size
+= notesize(&info
->psinfo
);
1583 fill_auxv_note(&info
->auxv
, current
->mm
);
1584 info
->size
+= notesize(&info
->auxv
);
1589 static size_t get_note_info_size(struct elf_note_info
*info
)
1595 * Write all the notes for each thread. When writing the first thread, the
1596 * process-wide notes are interleaved after the first thread-specific note.
1598 static int write_note_info(struct elf_note_info
*info
,
1599 struct file
*file
, loff_t
*foffset
)
1602 struct elf_thread_core_info
*t
= info
->thread
;
1607 if (!writenote(&t
->notes
[0], file
, foffset
))
1610 if (first
&& !writenote(&info
->psinfo
, file
, foffset
))
1612 if (first
&& !writenote(&info
->auxv
, file
, foffset
))
1615 for (i
= 1; i
< info
->thread_notes
; ++i
)
1616 if (t
->notes
[i
].data
&&
1617 !writenote(&t
->notes
[i
], file
, foffset
))
1627 static void free_note_info(struct elf_note_info
*info
)
1629 struct elf_thread_core_info
*threads
= info
->thread
;
1632 struct elf_thread_core_info
*t
= threads
;
1634 WARN_ON(t
->notes
[0].data
&& t
->notes
[0].data
!= &t
->prstatus
);
1635 for (i
= 1; i
< info
->thread_notes
; ++i
)
1636 kfree(t
->notes
[i
].data
);
1639 kfree(info
->psinfo
.data
);
1644 /* Here is the structure in which status of each thread is captured. */
1645 struct elf_thread_status
1647 struct list_head list
;
1648 struct elf_prstatus prstatus
; /* NT_PRSTATUS */
1649 elf_fpregset_t fpu
; /* NT_PRFPREG */
1650 struct task_struct
*thread
;
1651 #ifdef ELF_CORE_COPY_XFPREGS
1652 elf_fpxregset_t xfpu
; /* ELF_CORE_XFPREG_TYPE */
1654 struct memelfnote notes
[3];
1659 * In order to add the specific thread information for the elf file format,
1660 * we need to keep a linked list of every threads pr_status and then create
1661 * a single section for them in the final core file.
1663 static int elf_dump_thread_status(long signr
, struct elf_thread_status
*t
)
1666 struct task_struct
*p
= t
->thread
;
1669 fill_prstatus(&t
->prstatus
, p
, signr
);
1670 elf_core_copy_task_regs(p
, &t
->prstatus
.pr_reg
);
1672 fill_note(&t
->notes
[0], "CORE", NT_PRSTATUS
, sizeof(t
->prstatus
),
1675 sz
+= notesize(&t
->notes
[0]);
1677 if ((t
->prstatus
.pr_fpvalid
= elf_core_copy_task_fpregs(p
, NULL
,
1679 fill_note(&t
->notes
[1], "CORE", NT_PRFPREG
, sizeof(t
->fpu
),
1682 sz
+= notesize(&t
->notes
[1]);
1685 #ifdef ELF_CORE_COPY_XFPREGS
1686 if (elf_core_copy_task_xfpregs(p
, &t
->xfpu
)) {
1687 fill_note(&t
->notes
[2], "LINUX", ELF_CORE_XFPREG_TYPE
,
1688 sizeof(t
->xfpu
), &t
->xfpu
);
1690 sz
+= notesize(&t
->notes
[2]);
1696 struct elf_note_info
{
1697 struct memelfnote
*notes
;
1698 struct elf_prstatus
*prstatus
; /* NT_PRSTATUS */
1699 struct elf_prpsinfo
*psinfo
; /* NT_PRPSINFO */
1700 struct list_head thread_list
;
1701 elf_fpregset_t
*fpu
;
1702 #ifdef ELF_CORE_COPY_XFPREGS
1703 elf_fpxregset_t
*xfpu
;
1705 int thread_status_size
;
1709 static int elf_note_info_init(struct elf_note_info
*info
)
1711 memset(info
, 0, sizeof(*info
));
1712 INIT_LIST_HEAD(&info
->thread_list
);
1714 /* Allocate space for six ELF notes */
1715 info
->notes
= kmalloc(6 * sizeof(struct memelfnote
), GFP_KERNEL
);
1718 info
->psinfo
= kmalloc(sizeof(*info
->psinfo
), GFP_KERNEL
);
1721 info
->prstatus
= kmalloc(sizeof(*info
->prstatus
), GFP_KERNEL
);
1722 if (!info
->prstatus
)
1724 info
->fpu
= kmalloc(sizeof(*info
->fpu
), GFP_KERNEL
);
1727 #ifdef ELF_CORE_COPY_XFPREGS
1728 info
->xfpu
= kmalloc(sizeof(*info
->xfpu
), GFP_KERNEL
);
1733 #ifdef ELF_CORE_COPY_XFPREGS
1738 kfree(info
->prstatus
);
1740 kfree(info
->psinfo
);
1746 static int fill_note_info(struct elfhdr
*elf
, int phdrs
,
1747 struct elf_note_info
*info
,
1748 long signr
, struct pt_regs
*regs
)
1750 struct list_head
*t
;
1752 if (!elf_note_info_init(info
))
1756 struct core_thread
*ct
;
1757 struct elf_thread_status
*ets
;
1759 for (ct
= current
->mm
->core_state
->dumper
.next
;
1760 ct
; ct
= ct
->next
) {
1761 ets
= kzalloc(sizeof(*ets
), GFP_KERNEL
);
1765 ets
->thread
= ct
->task
;
1766 list_add(&ets
->list
, &info
->thread_list
);
1769 list_for_each(t
, &info
->thread_list
) {
1772 ets
= list_entry(t
, struct elf_thread_status
, list
);
1773 sz
= elf_dump_thread_status(signr
, ets
);
1774 info
->thread_status_size
+= sz
;
1777 /* now collect the dump for the current */
1778 memset(info
->prstatus
, 0, sizeof(*info
->prstatus
));
1779 fill_prstatus(info
->prstatus
, current
, signr
);
1780 elf_core_copy_regs(&info
->prstatus
->pr_reg
, regs
);
1783 fill_elf_header(elf
, phdrs
, ELF_ARCH
, ELF_CORE_EFLAGS
, ELF_OSABI
);
1786 * Set up the notes in similar form to SVR4 core dumps made
1787 * with info from their /proc.
1790 fill_note(info
->notes
+ 0, "CORE", NT_PRSTATUS
,
1791 sizeof(*info
->prstatus
), info
->prstatus
);
1792 fill_psinfo(info
->psinfo
, current
->group_leader
, current
->mm
);
1793 fill_note(info
->notes
+ 1, "CORE", NT_PRPSINFO
,
1794 sizeof(*info
->psinfo
), info
->psinfo
);
1798 fill_auxv_note(&info
->notes
[info
->numnote
++], current
->mm
);
1800 /* Try to dump the FPU. */
1801 info
->prstatus
->pr_fpvalid
= elf_core_copy_task_fpregs(current
, regs
,
1803 if (info
->prstatus
->pr_fpvalid
)
1804 fill_note(info
->notes
+ info
->numnote
++,
1805 "CORE", NT_PRFPREG
, sizeof(*info
->fpu
), info
->fpu
);
1806 #ifdef ELF_CORE_COPY_XFPREGS
1807 if (elf_core_copy_task_xfpregs(current
, info
->xfpu
))
1808 fill_note(info
->notes
+ info
->numnote
++,
1809 "LINUX", ELF_CORE_XFPREG_TYPE
,
1810 sizeof(*info
->xfpu
), info
->xfpu
);
1816 static size_t get_note_info_size(struct elf_note_info
*info
)
1821 for (i
= 0; i
< info
->numnote
; i
++)
1822 sz
+= notesize(info
->notes
+ i
);
1824 sz
+= info
->thread_status_size
;
1829 static int write_note_info(struct elf_note_info
*info
,
1830 struct file
*file
, loff_t
*foffset
)
1833 struct list_head
*t
;
1835 for (i
= 0; i
< info
->numnote
; i
++)
1836 if (!writenote(info
->notes
+ i
, file
, foffset
))
1839 /* write out the thread status notes section */
1840 list_for_each(t
, &info
->thread_list
) {
1841 struct elf_thread_status
*tmp
=
1842 list_entry(t
, struct elf_thread_status
, list
);
1844 for (i
= 0; i
< tmp
->num_notes
; i
++)
1845 if (!writenote(&tmp
->notes
[i
], file
, foffset
))
1852 static void free_note_info(struct elf_note_info
*info
)
1854 while (!list_empty(&info
->thread_list
)) {
1855 struct list_head
*tmp
= info
->thread_list
.next
;
1857 kfree(list_entry(tmp
, struct elf_thread_status
, list
));
1860 kfree(info
->prstatus
);
1861 kfree(info
->psinfo
);
1864 #ifdef ELF_CORE_COPY_XFPREGS
1871 static struct vm_area_struct
*first_vma(struct task_struct
*tsk
,
1872 struct vm_area_struct
*gate_vma
)
1874 struct vm_area_struct
*ret
= tsk
->mm
->mmap
;
1881 * Helper function for iterating across a vma list. It ensures that the caller
1882 * will visit `gate_vma' prior to terminating the search.
1884 static struct vm_area_struct
*next_vma(struct vm_area_struct
*this_vma
,
1885 struct vm_area_struct
*gate_vma
)
1887 struct vm_area_struct
*ret
;
1889 ret
= this_vma
->vm_next
;
1892 if (this_vma
== gate_vma
)
1900 * This is a two-pass process; first we find the offsets of the bits,
1901 * and then they are actually written out. If we run out of core limit
1904 static int elf_core_dump(long signr
, struct pt_regs
*regs
, struct file
*file
, unsigned long limit
)
1910 struct vm_area_struct
*vma
, *gate_vma
;
1911 struct elfhdr
*elf
= NULL
;
1912 loff_t offset
= 0, dataoff
, foffset
;
1913 unsigned long mm_flags
;
1914 struct elf_note_info info
;
1917 * We no longer stop all VM operations.
1919 * This is because those proceses that could possibly change map_count
1920 * or the mmap / vma pages are now blocked in do_exit on current
1921 * finishing this core dump.
1923 * Only ptrace can touch these memory addresses, but it doesn't change
1924 * the map_count or the pages allocated. So no possibility of crashing
1925 * exists while dumping the mm->vm_next areas to the core file.
1928 /* alloc memory for large data structures: too large to be on stack */
1929 elf
= kmalloc(sizeof(*elf
), GFP_KERNEL
);
1933 * The number of segs are recored into ELF header as 16bit value.
1934 * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
1936 segs
= current
->mm
->map_count
;
1937 #ifdef ELF_CORE_EXTRA_PHDRS
1938 segs
+= ELF_CORE_EXTRA_PHDRS
;
1941 gate_vma
= get_gate_vma(current
);
1942 if (gate_vma
!= NULL
)
1946 * Collect all the non-memory information about the process for the
1947 * notes. This also sets up the file header.
1949 if (!fill_note_info(elf
, segs
+ 1, /* including notes section */
1950 &info
, signr
, regs
))
1954 current
->flags
|= PF_DUMPCORE
;
1959 DUMP_WRITE(elf
, sizeof(*elf
));
1960 offset
+= sizeof(*elf
); /* Elf header */
1961 offset
+= (segs
+ 1) * sizeof(struct elf_phdr
); /* Program headers */
1964 /* Write notes phdr entry */
1966 struct elf_phdr phdr
;
1967 size_t sz
= get_note_info_size(&info
);
1969 sz
+= elf_coredump_extra_notes_size();
1971 fill_elf_note_phdr(&phdr
, sz
, offset
);
1973 DUMP_WRITE(&phdr
, sizeof(phdr
));
1976 dataoff
= offset
= roundup(offset
, ELF_EXEC_PAGESIZE
);
1979 * We must use the same mm->flags while dumping core to avoid
1980 * inconsistency between the program headers and bodies, otherwise an
1981 * unusable core file can be generated.
1983 mm_flags
= current
->mm
->flags
;
1985 /* Write program headers for segments dump */
1986 for (vma
= first_vma(current
, gate_vma
); vma
!= NULL
;
1987 vma
= next_vma(vma
, gate_vma
)) {
1988 struct elf_phdr phdr
;
1990 phdr
.p_type
= PT_LOAD
;
1991 phdr
.p_offset
= offset
;
1992 phdr
.p_vaddr
= vma
->vm_start
;
1994 phdr
.p_filesz
= vma_dump_size(vma
, mm_flags
);
1995 phdr
.p_memsz
= vma
->vm_end
- vma
->vm_start
;
1996 offset
+= phdr
.p_filesz
;
1997 phdr
.p_flags
= vma
->vm_flags
& VM_READ
? PF_R
: 0;
1998 if (vma
->vm_flags
& VM_WRITE
)
1999 phdr
.p_flags
|= PF_W
;
2000 if (vma
->vm_flags
& VM_EXEC
)
2001 phdr
.p_flags
|= PF_X
;
2002 phdr
.p_align
= ELF_EXEC_PAGESIZE
;
2004 DUMP_WRITE(&phdr
, sizeof(phdr
));
2007 #ifdef ELF_CORE_WRITE_EXTRA_PHDRS
2008 ELF_CORE_WRITE_EXTRA_PHDRS
;
2011 /* write out the notes section */
2012 if (!write_note_info(&info
, file
, &foffset
))
2015 if (elf_coredump_extra_notes_write(file
, &foffset
))
2019 if (!dump_seek(file
, dataoff
- foffset
))
2022 for (vma
= first_vma(current
, gate_vma
); vma
!= NULL
;
2023 vma
= next_vma(vma
, gate_vma
)) {
2027 end
= vma
->vm_start
+ vma_dump_size(vma
, mm_flags
);
2029 for (addr
= vma
->vm_start
; addr
< end
; addr
+= PAGE_SIZE
) {
2033 page
= get_dump_page(addr
);
2035 void *kaddr
= kmap(page
);
2036 stop
= ((size
+= PAGE_SIZE
) > limit
) ||
2037 !dump_write(file
, kaddr
, PAGE_SIZE
);
2039 page_cache_release(page
);
2041 stop
= !dump_seek(file
, PAGE_SIZE
);
2047 #ifdef ELF_CORE_WRITE_EXTRA_DATA
2048 ELF_CORE_WRITE_EXTRA_DATA
;
2055 free_note_info(&info
);
2061 #endif /* CONFIG_ELF_CORE */
2063 static int __init
init_elf_binfmt(void)
2065 return register_binfmt(&elf_format
);
2068 static void __exit
exit_elf_binfmt(void)
2070 /* Remove the COFF and ELF loaders. */
2071 unregister_binfmt(&elf_format
);
2074 core_initcall(init_elf_binfmt
);
2075 module_exit(exit_elf_binfmt
);
2076 MODULE_LICENSE("GPL");