4 * Copyright (C) 1991, 1992 Linus Torvalds
8 * #!-checking implemented by tytso.
11 * Demand-loading implemented 01.12.91 - no need to read anything but
12 * the header into memory. The inode of the executable is put into
13 * "current->executable", and page faults do the actual loading. Clean.
15 * Once more I can proudly say that linux stood up to being changed: it
16 * was less than 2 hours work to get demand-loading completely implemented.
18 * Demand loading changed July 1993 by Eric Youngdale. Use mmap instead,
19 * current->executable is only used by the procfs. This allows a dispatch
20 * table to check for several different types of binary formats. We keep
21 * trying until we recognize the file or we run out of supported binary
25 #include <linux/slab.h>
26 #include <linux/file.h>
27 #include <linux/fdtable.h>
29 #include <linux/vmacache.h>
30 #include <linux/stat.h>
31 #include <linux/fcntl.h>
32 #include <linux/swap.h>
33 #include <linux/string.h>
34 #include <linux/init.h>
35 #include <linux/sched/mm.h>
36 #include <linux/sched/coredump.h>
37 #include <linux/sched/signal.h>
38 #include <linux/sched/numa_balancing.h>
39 #include <linux/sched/task.h>
40 #include <linux/pagemap.h>
41 #include <linux/perf_event.h>
42 #include <linux/highmem.h>
43 #include <linux/spinlock.h>
44 #include <linux/key.h>
45 #include <linux/personality.h>
46 #include <linux/binfmts.h>
47 #include <linux/utsname.h>
48 #include <linux/pid_namespace.h>
49 #include <linux/module.h>
50 #include <linux/namei.h>
51 #include <linux/mount.h>
52 #include <linux/security.h>
53 #include <linux/syscalls.h>
54 #include <linux/tsacct_kern.h>
55 #include <linux/cn_proc.h>
56 #include <linux/audit.h>
57 #include <linux/tracehook.h>
58 #include <linux/kmod.h>
59 #include <linux/fsnotify.h>
60 #include <linux/fs_struct.h>
61 #include <linux/pipe_fs_i.h>
62 #include <linux/oom.h>
63 #include <linux/compat.h>
64 #include <linux/vmalloc.h>
66 #include <trace/events/fs.h>
68 #include <linux/uaccess.h>
69 #include <asm/mmu_context.h>
72 #include <trace/events/task.h>
75 #include <trace/events/sched.h>
77 int suid_dumpable
= 0;
79 static LIST_HEAD(formats
);
80 static DEFINE_RWLOCK(binfmt_lock
);
82 void __register_binfmt(struct linux_binfmt
* fmt
, int insert
)
85 if (WARN_ON(!fmt
->load_binary
))
87 write_lock(&binfmt_lock
);
88 insert
? list_add(&fmt
->lh
, &formats
) :
89 list_add_tail(&fmt
->lh
, &formats
);
90 write_unlock(&binfmt_lock
);
93 EXPORT_SYMBOL(__register_binfmt
);
95 void unregister_binfmt(struct linux_binfmt
* fmt
)
97 write_lock(&binfmt_lock
);
99 write_unlock(&binfmt_lock
);
102 EXPORT_SYMBOL(unregister_binfmt
);
104 static inline void put_binfmt(struct linux_binfmt
* fmt
)
106 module_put(fmt
->module
);
109 bool path_noexec(const struct path
*path
)
111 return (path
->mnt
->mnt_flags
& MNT_NOEXEC
) ||
112 (path
->mnt
->mnt_sb
->s_iflags
& SB_I_NOEXEC
);
115 bool path_nosuid(const struct path
*path
)
117 return !mnt_may_suid(path
->mnt
) ||
118 (path
->mnt
->mnt_sb
->s_iflags
& SB_I_NOSUID
);
120 EXPORT_SYMBOL(path_nosuid
);
124 * Note that a shared library must be both readable and executable due to
127 * Also note that we take the address to load from from the file itself.
129 SYSCALL_DEFINE1(uselib
, const char __user
*, library
)
131 struct linux_binfmt
*fmt
;
133 struct filename
*tmp
= getname(library
);
134 int error
= PTR_ERR(tmp
);
135 static const struct open_flags uselib_flags
= {
136 .open_flag
= O_LARGEFILE
| O_RDONLY
| __FMODE_EXEC
,
137 .acc_mode
= MAY_READ
| MAY_EXEC
,
138 .intent
= LOOKUP_OPEN
,
139 .lookup_flags
= LOOKUP_FOLLOW
,
145 file
= do_filp_open(AT_FDCWD
, tmp
, &uselib_flags
);
147 error
= PTR_ERR(file
);
152 if (!S_ISREG(file_inode(file
)->i_mode
))
156 if (path_noexec(&file
->f_path
))
163 read_lock(&binfmt_lock
);
164 list_for_each_entry(fmt
, &formats
, lh
) {
165 if (!fmt
->load_shlib
)
167 if (!try_module_get(fmt
->module
))
169 read_unlock(&binfmt_lock
);
170 error
= fmt
->load_shlib(file
);
171 read_lock(&binfmt_lock
);
173 if (error
!= -ENOEXEC
)
176 read_unlock(&binfmt_lock
);
182 #endif /* #ifdef CONFIG_USELIB */
186 * The nascent bprm->mm is not visible until exec_mmap() but it can
187 * use a lot of memory, account these pages in current->mm temporary
188 * for oom_badness()->get_mm_rss(). Once exec succeeds or fails, we
189 * change the counter back via acct_arg_size(0).
191 static void acct_arg_size(struct linux_binprm
*bprm
, unsigned long pages
)
193 struct mm_struct
*mm
= current
->mm
;
194 long diff
= (long)(pages
- bprm
->vma_pages
);
199 bprm
->vma_pages
= pages
;
200 add_mm_counter(mm
, MM_ANONPAGES
, diff
);
203 static struct page
*get_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
208 unsigned int gup_flags
= FOLL_FORCE
;
210 #ifdef CONFIG_STACK_GROWSUP
212 ret
= expand_downwards(bprm
->vma
, pos
);
219 gup_flags
|= FOLL_WRITE
;
222 * We are doing an exec(). 'current' is the process
223 * doing the exec and bprm->mm is the new process's mm.
225 ret
= get_user_pages_remote(current
, bprm
->mm
, pos
, 1, gup_flags
,
231 unsigned long size
= bprm
->vma
->vm_end
- bprm
->vma
->vm_start
;
232 unsigned long ptr_size
, limit
;
235 * Since the stack will hold pointers to the strings, we
236 * must account for them as well.
238 * The size calculation is the entire vma while each arg page is
239 * built, so each time we get here it's calculating how far it
240 * is currently (rather than each call being just the newly
241 * added size from the arg page). As a result, we need to
242 * always add the entire size of the pointers, so that on the
243 * last call to get_arg_page() we'll actually have the entire
246 ptr_size
= (bprm
->argc
+ bprm
->envc
) * sizeof(void *);
247 if (ptr_size
> ULONG_MAX
- size
)
251 acct_arg_size(bprm
, size
/ PAGE_SIZE
);
254 * We've historically supported up to 32 pages (ARG_MAX)
255 * of argument strings even with small stacks
261 * Limit to 1/4 of the max stack size or 3/4 of _STK_LIM
262 * (whichever is smaller) for the argv+env strings.
264 * - the remaining binfmt code will not run out of stack space,
265 * - the program will have a reasonable amount of stack left
268 limit
= _STK_LIM
/ 4 * 3;
269 limit
= min(limit
, rlimit(RLIMIT_STACK
) / 4);
281 static void put_arg_page(struct page
*page
)
286 static void free_arg_pages(struct linux_binprm
*bprm
)
290 static void flush_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
293 flush_cache_page(bprm
->vma
, pos
, page_to_pfn(page
));
296 static int __bprm_mm_init(struct linux_binprm
*bprm
)
299 struct vm_area_struct
*vma
= NULL
;
300 struct mm_struct
*mm
= bprm
->mm
;
302 bprm
->vma
= vma
= kmem_cache_zalloc(vm_area_cachep
, GFP_KERNEL
);
306 if (down_write_killable(&mm
->mmap_sem
)) {
313 * Place the stack at the largest stack address the architecture
314 * supports. Later, we'll move this to an appropriate place. We don't
315 * use STACK_TOP because that can depend on attributes which aren't
318 BUILD_BUG_ON(VM_STACK_FLAGS
& VM_STACK_INCOMPLETE_SETUP
);
319 vma
->vm_end
= STACK_TOP_MAX
;
320 vma
->vm_start
= vma
->vm_end
- PAGE_SIZE
;
321 vma
->vm_flags
= VM_SOFTDIRTY
| VM_STACK_FLAGS
| VM_STACK_INCOMPLETE_SETUP
;
322 vma
->vm_page_prot
= vm_get_page_prot(vma
->vm_flags
);
323 INIT_LIST_HEAD(&vma
->anon_vma_chain
);
325 err
= insert_vm_struct(mm
, vma
);
329 mm
->stack_vm
= mm
->total_vm
= 1;
330 arch_bprm_mm_init(mm
, vma
);
331 up_write(&mm
->mmap_sem
);
332 bprm
->p
= vma
->vm_end
- sizeof(void *);
335 up_write(&mm
->mmap_sem
);
338 kmem_cache_free(vm_area_cachep
, vma
);
342 static bool valid_arg_len(struct linux_binprm
*bprm
, long len
)
344 return len
<= MAX_ARG_STRLEN
;
349 static inline void acct_arg_size(struct linux_binprm
*bprm
, unsigned long pages
)
353 static struct page
*get_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
358 page
= bprm
->page
[pos
/ PAGE_SIZE
];
359 if (!page
&& write
) {
360 page
= alloc_page(GFP_HIGHUSER
|__GFP_ZERO
);
363 bprm
->page
[pos
/ PAGE_SIZE
] = page
;
369 static void put_arg_page(struct page
*page
)
373 static void free_arg_page(struct linux_binprm
*bprm
, int i
)
376 __free_page(bprm
->page
[i
]);
377 bprm
->page
[i
] = NULL
;
381 static void free_arg_pages(struct linux_binprm
*bprm
)
385 for (i
= 0; i
< MAX_ARG_PAGES
; i
++)
386 free_arg_page(bprm
, i
);
389 static void flush_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
394 static int __bprm_mm_init(struct linux_binprm
*bprm
)
396 bprm
->p
= PAGE_SIZE
* MAX_ARG_PAGES
- sizeof(void *);
400 static bool valid_arg_len(struct linux_binprm
*bprm
, long len
)
402 return len
<= bprm
->p
;
405 #endif /* CONFIG_MMU */
408 * Create a new mm_struct and populate it with a temporary stack
409 * vm_area_struct. We don't have enough context at this point to set the stack
410 * flags, permissions, and offset, so we use temporary values. We'll update
411 * them later in setup_arg_pages().
413 static int bprm_mm_init(struct linux_binprm
*bprm
)
416 struct mm_struct
*mm
= NULL
;
418 bprm
->mm
= mm
= mm_alloc();
423 err
= __bprm_mm_init(bprm
);
438 struct user_arg_ptr
{
443 const char __user
*const __user
*native
;
445 const compat_uptr_t __user
*compat
;
450 static const char __user
*get_user_arg_ptr(struct user_arg_ptr argv
, int nr
)
452 const char __user
*native
;
455 if (unlikely(argv
.is_compat
)) {
456 compat_uptr_t compat
;
458 if (get_user(compat
, argv
.ptr
.compat
+ nr
))
459 return ERR_PTR(-EFAULT
);
461 return compat_ptr(compat
);
465 if (get_user(native
, argv
.ptr
.native
+ nr
))
466 return ERR_PTR(-EFAULT
);
472 * count() counts the number of strings in array ARGV.
474 static int count(struct user_arg_ptr argv
, int max
)
478 if (argv
.ptr
.native
!= NULL
) {
480 const char __user
*p
= get_user_arg_ptr(argv
, i
);
492 if (fatal_signal_pending(current
))
493 return -ERESTARTNOHAND
;
501 * 'copy_strings()' copies argument/environment strings from the old
502 * processes's memory to the new process's stack. The call to get_user_pages()
503 * ensures the destination page is created and not swapped out.
505 static int copy_strings(int argc
, struct user_arg_ptr argv
,
506 struct linux_binprm
*bprm
)
508 struct page
*kmapped_page
= NULL
;
510 unsigned long kpos
= 0;
514 const char __user
*str
;
519 str
= get_user_arg_ptr(argv
, argc
);
523 len
= strnlen_user(str
, MAX_ARG_STRLEN
);
528 if (!valid_arg_len(bprm
, len
))
531 /* We're going to work our way backwords. */
537 int offset
, bytes_to_copy
;
539 if (fatal_signal_pending(current
)) {
540 ret
= -ERESTARTNOHAND
;
545 offset
= pos
% PAGE_SIZE
;
549 bytes_to_copy
= offset
;
550 if (bytes_to_copy
> len
)
553 offset
-= bytes_to_copy
;
554 pos
-= bytes_to_copy
;
555 str
-= bytes_to_copy
;
556 len
-= bytes_to_copy
;
558 if (!kmapped_page
|| kpos
!= (pos
& PAGE_MASK
)) {
561 page
= get_arg_page(bprm
, pos
, 1);
568 flush_kernel_dcache_page(kmapped_page
);
569 kunmap(kmapped_page
);
570 put_arg_page(kmapped_page
);
573 kaddr
= kmap(kmapped_page
);
574 kpos
= pos
& PAGE_MASK
;
575 flush_arg_page(bprm
, kpos
, kmapped_page
);
577 if (copy_from_user(kaddr
+offset
, str
, bytes_to_copy
)) {
586 flush_kernel_dcache_page(kmapped_page
);
587 kunmap(kmapped_page
);
588 put_arg_page(kmapped_page
);
594 * Like copy_strings, but get argv and its values from kernel memory.
596 int copy_strings_kernel(int argc
, const char *const *__argv
,
597 struct linux_binprm
*bprm
)
600 mm_segment_t oldfs
= get_fs();
601 struct user_arg_ptr argv
= {
602 .ptr
.native
= (const char __user
*const __user
*)__argv
,
606 r
= copy_strings(argc
, argv
, bprm
);
611 EXPORT_SYMBOL(copy_strings_kernel
);
616 * During bprm_mm_init(), we create a temporary stack at STACK_TOP_MAX. Once
617 * the binfmt code determines where the new stack should reside, we shift it to
618 * its final location. The process proceeds as follows:
620 * 1) Use shift to calculate the new vma endpoints.
621 * 2) Extend vma to cover both the old and new ranges. This ensures the
622 * arguments passed to subsequent functions are consistent.
623 * 3) Move vma's page tables to the new range.
624 * 4) Free up any cleared pgd range.
625 * 5) Shrink the vma to cover only the new range.
627 static int shift_arg_pages(struct vm_area_struct
*vma
, unsigned long shift
)
629 struct mm_struct
*mm
= vma
->vm_mm
;
630 unsigned long old_start
= vma
->vm_start
;
631 unsigned long old_end
= vma
->vm_end
;
632 unsigned long length
= old_end
- old_start
;
633 unsigned long new_start
= old_start
- shift
;
634 unsigned long new_end
= old_end
- shift
;
635 struct mmu_gather tlb
;
637 BUG_ON(new_start
> new_end
);
640 * ensure there are no vmas between where we want to go
643 if (vma
!= find_vma(mm
, new_start
))
647 * cover the whole range: [new_start, old_end)
649 if (vma_adjust(vma
, new_start
, old_end
, vma
->vm_pgoff
, NULL
))
653 * move the page tables downwards, on failure we rely on
654 * process cleanup to remove whatever mess we made.
656 if (length
!= move_page_tables(vma
, old_start
,
657 vma
, new_start
, length
, false))
661 tlb_gather_mmu(&tlb
, mm
, old_start
, old_end
);
662 if (new_end
> old_start
) {
664 * when the old and new regions overlap clear from new_end.
666 free_pgd_range(&tlb
, new_end
, old_end
, new_end
,
667 vma
->vm_next
? vma
->vm_next
->vm_start
: USER_PGTABLES_CEILING
);
670 * otherwise, clean from old_start; this is done to not touch
671 * the address space in [new_end, old_start) some architectures
672 * have constraints on va-space that make this illegal (IA64) -
673 * for the others its just a little faster.
675 free_pgd_range(&tlb
, old_start
, old_end
, new_end
,
676 vma
->vm_next
? vma
->vm_next
->vm_start
: USER_PGTABLES_CEILING
);
678 tlb_finish_mmu(&tlb
, old_start
, old_end
);
681 * Shrink the vma to just the new range. Always succeeds.
683 vma_adjust(vma
, new_start
, new_end
, vma
->vm_pgoff
, NULL
);
689 * Finalizes the stack vm_area_struct. The flags and permissions are updated,
690 * the stack is optionally relocated, and some extra space is added.
692 int setup_arg_pages(struct linux_binprm
*bprm
,
693 unsigned long stack_top
,
694 int executable_stack
)
697 unsigned long stack_shift
;
698 struct mm_struct
*mm
= current
->mm
;
699 struct vm_area_struct
*vma
= bprm
->vma
;
700 struct vm_area_struct
*prev
= NULL
;
701 unsigned long vm_flags
;
702 unsigned long stack_base
;
703 unsigned long stack_size
;
704 unsigned long stack_expand
;
705 unsigned long rlim_stack
;
707 #ifdef CONFIG_STACK_GROWSUP
708 /* Limit stack size */
709 stack_base
= rlimit_max(RLIMIT_STACK
);
710 if (stack_base
> STACK_SIZE_MAX
)
711 stack_base
= STACK_SIZE_MAX
;
713 /* Add space for stack randomization. */
714 stack_base
+= (STACK_RND_MASK
<< PAGE_SHIFT
);
716 /* Make sure we didn't let the argument array grow too large. */
717 if (vma
->vm_end
- vma
->vm_start
> stack_base
)
720 stack_base
= PAGE_ALIGN(stack_top
- stack_base
);
722 stack_shift
= vma
->vm_start
- stack_base
;
723 mm
->arg_start
= bprm
->p
- stack_shift
;
724 bprm
->p
= vma
->vm_end
- stack_shift
;
726 stack_top
= arch_align_stack(stack_top
);
727 stack_top
= PAGE_ALIGN(stack_top
);
729 if (unlikely(stack_top
< mmap_min_addr
) ||
730 unlikely(vma
->vm_end
- vma
->vm_start
>= stack_top
- mmap_min_addr
))
733 stack_shift
= vma
->vm_end
- stack_top
;
735 bprm
->p
-= stack_shift
;
736 mm
->arg_start
= bprm
->p
;
740 bprm
->loader
-= stack_shift
;
741 bprm
->exec
-= stack_shift
;
743 if (down_write_killable(&mm
->mmap_sem
))
746 vm_flags
= VM_STACK_FLAGS
;
749 * Adjust stack execute permissions; explicitly enable for
750 * EXSTACK_ENABLE_X, disable for EXSTACK_DISABLE_X and leave alone
751 * (arch default) otherwise.
753 if (unlikely(executable_stack
== EXSTACK_ENABLE_X
))
755 else if (executable_stack
== EXSTACK_DISABLE_X
)
756 vm_flags
&= ~VM_EXEC
;
757 vm_flags
|= mm
->def_flags
;
758 vm_flags
|= VM_STACK_INCOMPLETE_SETUP
;
760 ret
= mprotect_fixup(vma
, &prev
, vma
->vm_start
, vma
->vm_end
,
766 /* Move stack pages down in memory. */
768 ret
= shift_arg_pages(vma
, stack_shift
);
773 /* mprotect_fixup is overkill to remove the temporary stack flags */
774 vma
->vm_flags
&= ~VM_STACK_INCOMPLETE_SETUP
;
776 stack_expand
= 131072UL; /* randomly 32*4k (or 2*64k) pages */
777 stack_size
= vma
->vm_end
- vma
->vm_start
;
779 * Align this down to a page boundary as expand_stack
782 rlim_stack
= rlimit(RLIMIT_STACK
) & PAGE_MASK
;
783 #ifdef CONFIG_STACK_GROWSUP
784 if (stack_size
+ stack_expand
> rlim_stack
)
785 stack_base
= vma
->vm_start
+ rlim_stack
;
787 stack_base
= vma
->vm_end
+ stack_expand
;
789 if (stack_size
+ stack_expand
> rlim_stack
)
790 stack_base
= vma
->vm_end
- rlim_stack
;
792 stack_base
= vma
->vm_start
- stack_expand
;
794 current
->mm
->start_stack
= bprm
->p
;
795 ret
= expand_stack(vma
, stack_base
);
800 up_write(&mm
->mmap_sem
);
803 EXPORT_SYMBOL(setup_arg_pages
);
808 * Transfer the program arguments and environment from the holding pages
809 * onto the stack. The provided stack pointer is adjusted accordingly.
811 int transfer_args_to_stack(struct linux_binprm
*bprm
,
812 unsigned long *sp_location
)
814 unsigned long index
, stop
, sp
;
817 stop
= bprm
->p
>> PAGE_SHIFT
;
820 for (index
= MAX_ARG_PAGES
- 1; index
>= stop
; index
--) {
821 unsigned int offset
= index
== stop
? bprm
->p
& ~PAGE_MASK
: 0;
822 char *src
= kmap(bprm
->page
[index
]) + offset
;
823 sp
-= PAGE_SIZE
- offset
;
824 if (copy_to_user((void *) sp
, src
, PAGE_SIZE
- offset
) != 0)
826 kunmap(bprm
->page
[index
]);
836 EXPORT_SYMBOL(transfer_args_to_stack
);
838 #endif /* CONFIG_MMU */
840 static struct file
*do_open_execat(int fd
, struct filename
*name
, int flags
)
844 struct open_flags open_exec_flags
= {
845 .open_flag
= O_LARGEFILE
| O_RDONLY
| __FMODE_EXEC
,
846 .acc_mode
= MAY_EXEC
,
847 .intent
= LOOKUP_OPEN
,
848 .lookup_flags
= LOOKUP_FOLLOW
,
851 if ((flags
& ~(AT_SYMLINK_NOFOLLOW
| AT_EMPTY_PATH
)) != 0)
852 return ERR_PTR(-EINVAL
);
853 if (flags
& AT_SYMLINK_NOFOLLOW
)
854 open_exec_flags
.lookup_flags
&= ~LOOKUP_FOLLOW
;
855 if (flags
& AT_EMPTY_PATH
)
856 open_exec_flags
.lookup_flags
|= LOOKUP_EMPTY
;
858 file
= do_filp_open(fd
, name
, &open_exec_flags
);
863 if (!S_ISREG(file_inode(file
)->i_mode
))
866 if (path_noexec(&file
->f_path
))
869 err
= deny_write_access(file
);
873 if (name
->name
[0] != '\0')
876 trace_open_exec(name
->name
);
886 struct file
*open_exec(const char *name
)
888 struct filename
*filename
= getname_kernel(name
);
889 struct file
*f
= ERR_CAST(filename
);
891 if (!IS_ERR(filename
)) {
892 f
= do_open_execat(AT_FDCWD
, filename
, 0);
897 EXPORT_SYMBOL(open_exec
);
899 int kernel_read(struct file
*file
, loff_t offset
,
900 char *addr
, unsigned long count
)
908 /* The cast to a user pointer is valid due to the set_fs() */
909 result
= vfs_read(file
, (void __user
*)addr
, count
, &pos
);
914 EXPORT_SYMBOL(kernel_read
);
916 int kernel_read_file(struct file
*file
, void **buf
, loff_t
*size
,
917 loff_t max_size
, enum kernel_read_file_id id
)
923 if (!S_ISREG(file_inode(file
)->i_mode
) || max_size
< 0)
926 ret
= security_kernel_read_file(file
, id
);
930 ret
= deny_write_access(file
);
934 i_size
= i_size_read(file_inode(file
));
935 if (max_size
> 0 && i_size
> max_size
) {
944 if (id
!= READING_FIRMWARE_PREALLOC_BUFFER
)
945 *buf
= vmalloc(i_size
);
952 while (pos
< i_size
) {
953 bytes
= kernel_read(file
, pos
, (char *)(*buf
) + pos
,
970 ret
= security_kernel_post_read_file(file
, *buf
, i_size
, id
);
976 if (id
!= READING_FIRMWARE_PREALLOC_BUFFER
) {
983 allow_write_access(file
);
986 EXPORT_SYMBOL_GPL(kernel_read_file
);
988 int kernel_read_file_from_path(char *path
, void **buf
, loff_t
*size
,
989 loff_t max_size
, enum kernel_read_file_id id
)
997 file
= filp_open(path
, O_RDONLY
, 0);
999 return PTR_ERR(file
);
1001 ret
= kernel_read_file(file
, buf
, size
, max_size
, id
);
1005 EXPORT_SYMBOL_GPL(kernel_read_file_from_path
);
1007 int kernel_read_file_from_fd(int fd
, void **buf
, loff_t
*size
, loff_t max_size
,
1008 enum kernel_read_file_id id
)
1010 struct fd f
= fdget(fd
);
1016 ret
= kernel_read_file(f
.file
, buf
, size
, max_size
, id
);
1021 EXPORT_SYMBOL_GPL(kernel_read_file_from_fd
);
1023 ssize_t
read_code(struct file
*file
, unsigned long addr
, loff_t pos
, size_t len
)
1025 ssize_t res
= vfs_read(file
, (void __user
*)addr
, len
, &pos
);
1027 flush_icache_range(addr
, addr
+ len
);
1030 EXPORT_SYMBOL(read_code
);
1032 static int exec_mmap(struct mm_struct
*mm
)
1034 struct task_struct
*tsk
;
1035 struct mm_struct
*old_mm
, *active_mm
;
1037 /* Notify parent that we're no longer interested in the old VM */
1039 old_mm
= current
->mm
;
1040 mm_release(tsk
, old_mm
);
1043 sync_mm_rss(old_mm
);
1045 * Make sure that if there is a core dump in progress
1046 * for the old mm, we get out and die instead of going
1047 * through with the exec. We must hold mmap_sem around
1048 * checking core_state and changing tsk->mm.
1050 down_read(&old_mm
->mmap_sem
);
1051 if (unlikely(old_mm
->core_state
)) {
1052 up_read(&old_mm
->mmap_sem
);
1057 active_mm
= tsk
->active_mm
;
1059 tsk
->active_mm
= mm
;
1060 activate_mm(active_mm
, mm
);
1061 tsk
->mm
->vmacache_seqnum
= 0;
1062 vmacache_flush(tsk
);
1065 up_read(&old_mm
->mmap_sem
);
1066 BUG_ON(active_mm
!= old_mm
);
1067 setmax_mm_hiwater_rss(&tsk
->signal
->maxrss
, old_mm
);
1068 mm_update_next_owner(old_mm
);
1077 * This function makes sure the current process has its own signal table,
1078 * so that flush_signal_handlers can later reset the handlers without
1079 * disturbing other processes. (Other processes might share the signal
1080 * table via the CLONE_SIGHAND option to clone().)
1082 static int de_thread(struct task_struct
*tsk
)
1084 struct signal_struct
*sig
= tsk
->signal
;
1085 struct sighand_struct
*oldsighand
= tsk
->sighand
;
1086 spinlock_t
*lock
= &oldsighand
->siglock
;
1088 if (thread_group_empty(tsk
))
1089 goto no_thread_group
;
1092 * Kill all other threads in the thread group.
1094 spin_lock_irq(lock
);
1095 if (signal_group_exit(sig
)) {
1097 * Another group action in progress, just
1098 * return so that the signal is processed.
1100 spin_unlock_irq(lock
);
1104 sig
->group_exit_task
= tsk
;
1105 sig
->notify_count
= zap_other_threads(tsk
);
1106 if (!thread_group_leader(tsk
))
1107 sig
->notify_count
--;
1109 while (sig
->notify_count
) {
1110 __set_current_state(TASK_KILLABLE
);
1111 spin_unlock_irq(lock
);
1113 if (unlikely(__fatal_signal_pending(tsk
)))
1115 spin_lock_irq(lock
);
1117 spin_unlock_irq(lock
);
1120 * At this point all other threads have exited, all we have to
1121 * do is to wait for the thread group leader to become inactive,
1122 * and to assume its PID:
1124 if (!thread_group_leader(tsk
)) {
1125 struct task_struct
*leader
= tsk
->group_leader
;
1128 cgroup_threadgroup_change_begin(tsk
);
1129 write_lock_irq(&tasklist_lock
);
1131 * Do this under tasklist_lock to ensure that
1132 * exit_notify() can't miss ->group_exit_task
1134 sig
->notify_count
= -1;
1135 if (likely(leader
->exit_state
))
1137 __set_current_state(TASK_KILLABLE
);
1138 write_unlock_irq(&tasklist_lock
);
1139 cgroup_threadgroup_change_end(tsk
);
1141 if (unlikely(__fatal_signal_pending(tsk
)))
1146 * The only record we have of the real-time age of a
1147 * process, regardless of execs it's done, is start_time.
1148 * All the past CPU time is accumulated in signal_struct
1149 * from sister threads now dead. But in this non-leader
1150 * exec, nothing survives from the original leader thread,
1151 * whose birth marks the true age of this process now.
1152 * When we take on its identity by switching to its PID, we
1153 * also take its birthdate (always earlier than our own).
1155 tsk
->start_time
= leader
->start_time
;
1156 tsk
->real_start_time
= leader
->real_start_time
;
1158 BUG_ON(!same_thread_group(leader
, tsk
));
1159 BUG_ON(has_group_leader_pid(tsk
));
1161 * An exec() starts a new thread group with the
1162 * TGID of the previous thread group. Rehash the
1163 * two threads with a switched PID, and release
1164 * the former thread group leader:
1167 /* Become a process group leader with the old leader's pid.
1168 * The old leader becomes a thread of the this thread group.
1169 * Note: The old leader also uses this pid until release_task
1170 * is called. Odd but simple and correct.
1172 tsk
->pid
= leader
->pid
;
1173 change_pid(tsk
, PIDTYPE_PID
, task_pid(leader
));
1174 transfer_pid(leader
, tsk
, PIDTYPE_PGID
);
1175 transfer_pid(leader
, tsk
, PIDTYPE_SID
);
1177 list_replace_rcu(&leader
->tasks
, &tsk
->tasks
);
1178 list_replace_init(&leader
->sibling
, &tsk
->sibling
);
1180 tsk
->group_leader
= tsk
;
1181 leader
->group_leader
= tsk
;
1183 tsk
->exit_signal
= SIGCHLD
;
1184 leader
->exit_signal
= -1;
1186 BUG_ON(leader
->exit_state
!= EXIT_ZOMBIE
);
1187 leader
->exit_state
= EXIT_DEAD
;
1190 * We are going to release_task()->ptrace_unlink() silently,
1191 * the tracer can sleep in do_wait(). EXIT_DEAD guarantees
1192 * the tracer wont't block again waiting for this thread.
1194 if (unlikely(leader
->ptrace
))
1195 __wake_up_parent(leader
, leader
->parent
);
1196 write_unlock_irq(&tasklist_lock
);
1197 cgroup_threadgroup_change_end(tsk
);
1199 release_task(leader
);
1202 sig
->group_exit_task
= NULL
;
1203 sig
->notify_count
= 0;
1206 /* we have changed execution domain */
1207 tsk
->exit_signal
= SIGCHLD
;
1209 #ifdef CONFIG_POSIX_TIMERS
1211 flush_itimer_signals();
1214 if (atomic_read(&oldsighand
->count
) != 1) {
1215 struct sighand_struct
*newsighand
;
1217 * This ->sighand is shared with the CLONE_SIGHAND
1218 * but not CLONE_THREAD task, switch to the new one.
1220 newsighand
= kmem_cache_alloc(sighand_cachep
, GFP_KERNEL
);
1224 atomic_set(&newsighand
->count
, 1);
1225 memcpy(newsighand
->action
, oldsighand
->action
,
1226 sizeof(newsighand
->action
));
1228 write_lock_irq(&tasklist_lock
);
1229 spin_lock(&oldsighand
->siglock
);
1230 rcu_assign_pointer(tsk
->sighand
, newsighand
);
1231 spin_unlock(&oldsighand
->siglock
);
1232 write_unlock_irq(&tasklist_lock
);
1234 __cleanup_sighand(oldsighand
);
1237 BUG_ON(!thread_group_leader(tsk
));
1241 /* protects against exit_notify() and __exit_signal() */
1242 read_lock(&tasklist_lock
);
1243 sig
->group_exit_task
= NULL
;
1244 sig
->notify_count
= 0;
1245 read_unlock(&tasklist_lock
);
1249 char *get_task_comm(char *buf
, struct task_struct
*tsk
)
1251 /* buf must be at least sizeof(tsk->comm) in size */
1253 strncpy(buf
, tsk
->comm
, sizeof(tsk
->comm
));
1257 EXPORT_SYMBOL_GPL(get_task_comm
);
1260 * These functions flushes out all traces of the currently running executable
1261 * so that a new one can be started
1264 void __set_task_comm(struct task_struct
*tsk
, const char *buf
, bool exec
)
1267 trace_task_rename(tsk
, buf
);
1268 strlcpy(tsk
->comm
, buf
, sizeof(tsk
->comm
));
1270 perf_event_comm(tsk
, exec
);
1273 int flush_old_exec(struct linux_binprm
* bprm
)
1278 * Make sure we have a private signal table and that
1279 * we are unassociated from the previous thread group.
1281 retval
= de_thread(current
);
1286 * Must be called _before_ exec_mmap() as bprm->mm is
1287 * not visibile until then. This also enables the update
1290 set_mm_exe_file(bprm
->mm
, bprm
->file
);
1293 * Release all of the old mmap stuff
1295 acct_arg_size(bprm
, 0);
1296 retval
= exec_mmap(bprm
->mm
);
1300 bprm
->mm
= NULL
; /* We're using it now */
1303 current
->flags
&= ~(PF_RANDOMIZE
| PF_FORKNOEXEC
| PF_KTHREAD
|
1304 PF_NOFREEZE
| PF_NO_SETAFFINITY
);
1306 current
->personality
&= ~bprm
->per_clear
;
1309 * We have to apply CLOEXEC before we change whether the process is
1310 * dumpable (in setup_new_exec) to avoid a race with a process in userspace
1311 * trying to access the should-be-closed file descriptors of a process
1312 * undergoing exec(2).
1314 do_close_on_exec(current
->files
);
1320 EXPORT_SYMBOL(flush_old_exec
);
1322 void would_dump(struct linux_binprm
*bprm
, struct file
*file
)
1324 struct inode
*inode
= file_inode(file
);
1325 if (inode_permission(inode
, MAY_READ
) < 0) {
1326 struct user_namespace
*old
, *user_ns
;
1327 bprm
->interp_flags
|= BINPRM_FLAGS_ENFORCE_NONDUMP
;
1329 /* Ensure mm->user_ns contains the executable */
1330 user_ns
= old
= bprm
->mm
->user_ns
;
1331 while ((user_ns
!= &init_user_ns
) &&
1332 !privileged_wrt_inode_uidgid(user_ns
, inode
))
1333 user_ns
= user_ns
->parent
;
1335 if (old
!= user_ns
) {
1336 bprm
->mm
->user_ns
= get_user_ns(user_ns
);
1341 EXPORT_SYMBOL(would_dump
);
1343 void setup_new_exec(struct linux_binprm
* bprm
)
1345 arch_pick_mmap_layout(current
->mm
);
1347 /* This is the point of no return */
1348 current
->sas_ss_sp
= current
->sas_ss_size
= 0;
1350 if (uid_eq(current_euid(), current_uid()) && gid_eq(current_egid(), current_gid()))
1351 set_dumpable(current
->mm
, SUID_DUMP_USER
);
1353 set_dumpable(current
->mm
, suid_dumpable
);
1355 arch_setup_new_exec();
1357 __set_task_comm(current
, kbasename(bprm
->filename
), true);
1359 /* Set the new mm task size. We have to do that late because it may
1360 * depend on TIF_32BIT which is only updated in flush_thread() on
1361 * some architectures like powerpc
1363 current
->mm
->task_size
= TASK_SIZE
;
1365 /* install the new credentials */
1366 if (!uid_eq(bprm
->cred
->uid
, current_euid()) ||
1367 !gid_eq(bprm
->cred
->gid
, current_egid())) {
1368 current
->pdeath_signal
= 0;
1370 if (bprm
->interp_flags
& BINPRM_FLAGS_ENFORCE_NONDUMP
)
1371 set_dumpable(current
->mm
, suid_dumpable
);
1374 /* An exec changes our domain. We are no longer part of the thread
1376 current
->self_exec_id
++;
1377 flush_signal_handlers(current
, 0);
1379 EXPORT_SYMBOL(setup_new_exec
);
1382 * Prepare credentials and lock ->cred_guard_mutex.
1383 * install_exec_creds() commits the new creds and drops the lock.
1384 * Or, if exec fails before, free_bprm() should release ->cred and
1387 int prepare_bprm_creds(struct linux_binprm
*bprm
)
1389 if (mutex_lock_interruptible(¤t
->signal
->cred_guard_mutex
))
1390 return -ERESTARTNOINTR
;
1392 bprm
->cred
= prepare_exec_creds();
1393 if (likely(bprm
->cred
))
1396 mutex_unlock(¤t
->signal
->cred_guard_mutex
);
1400 static void free_bprm(struct linux_binprm
*bprm
)
1402 free_arg_pages(bprm
);
1404 mutex_unlock(¤t
->signal
->cred_guard_mutex
);
1405 abort_creds(bprm
->cred
);
1408 allow_write_access(bprm
->file
);
1411 /* If a binfmt changed the interp, free it. */
1412 if (bprm
->interp
!= bprm
->filename
)
1413 kfree(bprm
->interp
);
1417 int bprm_change_interp(char *interp
, struct linux_binprm
*bprm
)
1419 /* If a binfmt changed the interp, free it first. */
1420 if (bprm
->interp
!= bprm
->filename
)
1421 kfree(bprm
->interp
);
1422 bprm
->interp
= kstrdup(interp
, GFP_KERNEL
);
1427 EXPORT_SYMBOL(bprm_change_interp
);
1430 * install the new credentials for this executable
1432 void install_exec_creds(struct linux_binprm
*bprm
)
1434 security_bprm_committing_creds(bprm
);
1436 commit_creds(bprm
->cred
);
1440 * Disable monitoring for regular users
1441 * when executing setuid binaries. Must
1442 * wait until new credentials are committed
1443 * by commit_creds() above
1445 if (get_dumpable(current
->mm
) != SUID_DUMP_USER
)
1446 perf_event_exit_task(current
);
1448 * cred_guard_mutex must be held at least to this point to prevent
1449 * ptrace_attach() from altering our determination of the task's
1450 * credentials; any time after this it may be unlocked.
1452 security_bprm_committed_creds(bprm
);
1453 mutex_unlock(¤t
->signal
->cred_guard_mutex
);
1455 EXPORT_SYMBOL(install_exec_creds
);
1458 * determine how safe it is to execute the proposed program
1459 * - the caller must hold ->cred_guard_mutex to protect against
1460 * PTRACE_ATTACH or seccomp thread-sync
1462 static void check_unsafe_exec(struct linux_binprm
*bprm
)
1464 struct task_struct
*p
= current
, *t
;
1468 bprm
->unsafe
|= LSM_UNSAFE_PTRACE
;
1471 * This isn't strictly necessary, but it makes it harder for LSMs to
1474 if (task_no_new_privs(current
))
1475 bprm
->unsafe
|= LSM_UNSAFE_NO_NEW_PRIVS
;
1479 spin_lock(&p
->fs
->lock
);
1481 while_each_thread(p
, t
) {
1487 if (p
->fs
->users
> n_fs
)
1488 bprm
->unsafe
|= LSM_UNSAFE_SHARE
;
1491 spin_unlock(&p
->fs
->lock
);
1494 static void bprm_fill_uid(struct linux_binprm
*bprm
)
1496 struct inode
*inode
;
1502 * Since this can be called multiple times (via prepare_binprm),
1503 * we must clear any previous work done when setting set[ug]id
1504 * bits from any earlier bprm->file uses (for example when run
1505 * first for a setuid script then again for its interpreter).
1507 bprm
->cred
->euid
= current_euid();
1508 bprm
->cred
->egid
= current_egid();
1510 if (path_nosuid(&bprm
->file
->f_path
))
1513 if (task_no_new_privs(current
))
1516 inode
= bprm
->file
->f_path
.dentry
->d_inode
;
1517 mode
= READ_ONCE(inode
->i_mode
);
1518 if (!(mode
& (S_ISUID
|S_ISGID
)))
1521 /* Be careful if suid/sgid is set */
1524 /* reload atomically mode/uid/gid now that lock held */
1525 mode
= inode
->i_mode
;
1528 inode_unlock(inode
);
1530 /* We ignore suid/sgid if there are no mappings for them in the ns */
1531 if (!kuid_has_mapping(bprm
->cred
->user_ns
, uid
) ||
1532 !kgid_has_mapping(bprm
->cred
->user_ns
, gid
))
1535 if (mode
& S_ISUID
) {
1536 bprm
->per_clear
|= PER_CLEAR_ON_SETID
;
1537 bprm
->cred
->euid
= uid
;
1540 if ((mode
& (S_ISGID
| S_IXGRP
)) == (S_ISGID
| S_IXGRP
)) {
1541 bprm
->per_clear
|= PER_CLEAR_ON_SETID
;
1542 bprm
->cred
->egid
= gid
;
1547 * Fill the binprm structure from the inode.
1548 * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes
1550 * This may be called multiple times for binary chains (scripts for example).
1552 int prepare_binprm(struct linux_binprm
*bprm
)
1556 bprm_fill_uid(bprm
);
1558 /* fill in binprm security blob */
1559 retval
= security_bprm_set_creds(bprm
);
1562 bprm
->cred_prepared
= 1;
1564 memset(bprm
->buf
, 0, BINPRM_BUF_SIZE
);
1565 return kernel_read(bprm
->file
, 0, bprm
->buf
, BINPRM_BUF_SIZE
);
1568 EXPORT_SYMBOL(prepare_binprm
);
1571 * Arguments are '\0' separated strings found at the location bprm->p
1572 * points to; chop off the first by relocating brpm->p to right after
1573 * the first '\0' encountered.
1575 int remove_arg_zero(struct linux_binprm
*bprm
)
1578 unsigned long offset
;
1586 offset
= bprm
->p
& ~PAGE_MASK
;
1587 page
= get_arg_page(bprm
, bprm
->p
, 0);
1592 kaddr
= kmap_atomic(page
);
1594 for (; offset
< PAGE_SIZE
&& kaddr
[offset
];
1595 offset
++, bprm
->p
++)
1598 kunmap_atomic(kaddr
);
1600 } while (offset
== PAGE_SIZE
);
1609 EXPORT_SYMBOL(remove_arg_zero
);
1611 #define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e))
1613 * cycle the list of binary formats handler, until one recognizes the image
1615 int search_binary_handler(struct linux_binprm
*bprm
)
1617 bool need_retry
= IS_ENABLED(CONFIG_MODULES
);
1618 struct linux_binfmt
*fmt
;
1621 /* This allows 4 levels of binfmt rewrites before failing hard. */
1622 if (bprm
->recursion_depth
> 5)
1625 retval
= security_bprm_check(bprm
);
1631 read_lock(&binfmt_lock
);
1632 list_for_each_entry(fmt
, &formats
, lh
) {
1633 if (!try_module_get(fmt
->module
))
1635 read_unlock(&binfmt_lock
);
1636 bprm
->recursion_depth
++;
1637 retval
= fmt
->load_binary(bprm
);
1638 read_lock(&binfmt_lock
);
1640 bprm
->recursion_depth
--;
1641 if (retval
< 0 && !bprm
->mm
) {
1642 /* we got to flush_old_exec() and failed after it */
1643 read_unlock(&binfmt_lock
);
1644 force_sigsegv(SIGSEGV
, current
);
1647 if (retval
!= -ENOEXEC
|| !bprm
->file
) {
1648 read_unlock(&binfmt_lock
);
1652 read_unlock(&binfmt_lock
);
1655 if (printable(bprm
->buf
[0]) && printable(bprm
->buf
[1]) &&
1656 printable(bprm
->buf
[2]) && printable(bprm
->buf
[3]))
1658 if (request_module("binfmt-%04x", *(ushort
*)(bprm
->buf
+ 2)) < 0)
1666 EXPORT_SYMBOL(search_binary_handler
);
1668 static int exec_binprm(struct linux_binprm
*bprm
)
1670 pid_t old_pid
, old_vpid
;
1673 /* Need to fetch pid before load_binary changes it */
1674 old_pid
= current
->pid
;
1676 old_vpid
= task_pid_nr_ns(current
, task_active_pid_ns(current
->parent
));
1679 ret
= search_binary_handler(bprm
);
1682 trace_sched_process_exec(current
, old_pid
, bprm
);
1683 ptrace_event(PTRACE_EVENT_EXEC
, old_vpid
);
1684 proc_exec_connector(current
);
1691 * sys_execve() executes a new program.
1693 static int do_execveat_common(int fd
, struct filename
*filename
,
1694 struct user_arg_ptr argv
,
1695 struct user_arg_ptr envp
,
1698 char *pathbuf
= NULL
;
1699 struct linux_binprm
*bprm
;
1701 struct files_struct
*displaced
;
1704 if (IS_ERR(filename
))
1705 return PTR_ERR(filename
);
1708 * We move the actual failure in case of RLIMIT_NPROC excess from
1709 * set*uid() to execve() because too many poorly written programs
1710 * don't check setuid() return code. Here we additionally recheck
1711 * whether NPROC limit is still exceeded.
1713 if ((current
->flags
& PF_NPROC_EXCEEDED
) &&
1714 atomic_read(¤t_user()->processes
) > rlimit(RLIMIT_NPROC
)) {
1719 /* We're below the limit (still or again), so we don't want to make
1720 * further execve() calls fail. */
1721 current
->flags
&= ~PF_NPROC_EXCEEDED
;
1723 retval
= unshare_files(&displaced
);
1728 bprm
= kzalloc(sizeof(*bprm
), GFP_KERNEL
);
1732 retval
= prepare_bprm_creds(bprm
);
1736 check_unsafe_exec(bprm
);
1737 current
->in_execve
= 1;
1739 file
= do_open_execat(fd
, filename
, flags
);
1740 retval
= PTR_ERR(file
);
1747 if (fd
== AT_FDCWD
|| filename
->name
[0] == '/') {
1748 bprm
->filename
= filename
->name
;
1750 if (filename
->name
[0] == '\0')
1751 pathbuf
= kasprintf(GFP_TEMPORARY
, "/dev/fd/%d", fd
);
1753 pathbuf
= kasprintf(GFP_TEMPORARY
, "/dev/fd/%d/%s",
1754 fd
, filename
->name
);
1760 * Record that a name derived from an O_CLOEXEC fd will be
1761 * inaccessible after exec. Relies on having exclusive access to
1762 * current->files (due to unshare_files above).
1764 if (close_on_exec(fd
, rcu_dereference_raw(current
->files
->fdt
)))
1765 bprm
->interp_flags
|= BINPRM_FLAGS_PATH_INACCESSIBLE
;
1766 bprm
->filename
= pathbuf
;
1768 bprm
->interp
= bprm
->filename
;
1770 retval
= bprm_mm_init(bprm
);
1774 bprm
->argc
= count(argv
, MAX_ARG_STRINGS
);
1775 if ((retval
= bprm
->argc
) < 0)
1778 bprm
->envc
= count(envp
, MAX_ARG_STRINGS
);
1779 if ((retval
= bprm
->envc
) < 0)
1782 retval
= prepare_binprm(bprm
);
1786 retval
= copy_strings_kernel(1, &bprm
->filename
, bprm
);
1790 bprm
->exec
= bprm
->p
;
1791 retval
= copy_strings(bprm
->envc
, envp
, bprm
);
1795 retval
= copy_strings(bprm
->argc
, argv
, bprm
);
1799 would_dump(bprm
, bprm
->file
);
1801 retval
= exec_binprm(bprm
);
1805 /* execve succeeded */
1806 current
->fs
->in_exec
= 0;
1807 current
->in_execve
= 0;
1808 acct_update_integrals(current
);
1809 task_numa_free(current
);
1814 put_files_struct(displaced
);
1819 acct_arg_size(bprm
, 0);
1824 current
->fs
->in_exec
= 0;
1825 current
->in_execve
= 0;
1833 reset_files_struct(displaced
);
1839 int do_execve(struct filename
*filename
,
1840 const char __user
*const __user
*__argv
,
1841 const char __user
*const __user
*__envp
)
1843 struct user_arg_ptr argv
= { .ptr
.native
= __argv
};
1844 struct user_arg_ptr envp
= { .ptr
.native
= __envp
};
1845 return do_execveat_common(AT_FDCWD
, filename
, argv
, envp
, 0);
1848 int do_execveat(int fd
, struct filename
*filename
,
1849 const char __user
*const __user
*__argv
,
1850 const char __user
*const __user
*__envp
,
1853 struct user_arg_ptr argv
= { .ptr
.native
= __argv
};
1854 struct user_arg_ptr envp
= { .ptr
.native
= __envp
};
1856 return do_execveat_common(fd
, filename
, argv
, envp
, flags
);
1859 #ifdef CONFIG_COMPAT
1860 static int compat_do_execve(struct filename
*filename
,
1861 const compat_uptr_t __user
*__argv
,
1862 const compat_uptr_t __user
*__envp
)
1864 struct user_arg_ptr argv
= {
1866 .ptr
.compat
= __argv
,
1868 struct user_arg_ptr envp
= {
1870 .ptr
.compat
= __envp
,
1872 return do_execveat_common(AT_FDCWD
, filename
, argv
, envp
, 0);
1875 static int compat_do_execveat(int fd
, struct filename
*filename
,
1876 const compat_uptr_t __user
*__argv
,
1877 const compat_uptr_t __user
*__envp
,
1880 struct user_arg_ptr argv
= {
1882 .ptr
.compat
= __argv
,
1884 struct user_arg_ptr envp
= {
1886 .ptr
.compat
= __envp
,
1888 return do_execveat_common(fd
, filename
, argv
, envp
, flags
);
1892 void set_binfmt(struct linux_binfmt
*new)
1894 struct mm_struct
*mm
= current
->mm
;
1897 module_put(mm
->binfmt
->module
);
1901 __module_get(new->module
);
1903 EXPORT_SYMBOL(set_binfmt
);
1906 * set_dumpable stores three-value SUID_DUMP_* into mm->flags.
1908 void set_dumpable(struct mm_struct
*mm
, int value
)
1910 unsigned long old
, new;
1912 if (WARN_ON((unsigned)value
> SUID_DUMP_ROOT
))
1916 old
= ACCESS_ONCE(mm
->flags
);
1917 new = (old
& ~MMF_DUMPABLE_MASK
) | value
;
1918 } while (cmpxchg(&mm
->flags
, old
, new) != old
);
1921 SYSCALL_DEFINE3(execve
,
1922 const char __user
*, filename
,
1923 const char __user
*const __user
*, argv
,
1924 const char __user
*const __user
*, envp
)
1926 return do_execve(getname(filename
), argv
, envp
);
1929 SYSCALL_DEFINE5(execveat
,
1930 int, fd
, const char __user
*, filename
,
1931 const char __user
*const __user
*, argv
,
1932 const char __user
*const __user
*, envp
,
1935 int lookup_flags
= (flags
& AT_EMPTY_PATH
) ? LOOKUP_EMPTY
: 0;
1937 return do_execveat(fd
,
1938 getname_flags(filename
, lookup_flags
, NULL
),
1942 #ifdef CONFIG_COMPAT
1943 COMPAT_SYSCALL_DEFINE3(execve
, const char __user
*, filename
,
1944 const compat_uptr_t __user
*, argv
,
1945 const compat_uptr_t __user
*, envp
)
1947 return compat_do_execve(getname(filename
), argv
, envp
);
1950 COMPAT_SYSCALL_DEFINE5(execveat
, int, fd
,
1951 const char __user
*, filename
,
1952 const compat_uptr_t __user
*, argv
,
1953 const compat_uptr_t __user
*, envp
,
1956 int lookup_flags
= (flags
& AT_EMPTY_PATH
) ? LOOKUP_EMPTY
: 0;
1958 return compat_do_execveat(fd
,
1959 getname_flags(filename
, lookup_flags
, NULL
),