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/pagemap.h>
40 #include <linux/perf_event.h>
41 #include <linux/highmem.h>
42 #include <linux/spinlock.h>
43 #include <linux/key.h>
44 #include <linux/personality.h>
45 #include <linux/binfmts.h>
46 #include <linux/utsname.h>
47 #include <linux/pid_namespace.h>
48 #include <linux/module.h>
49 #include <linux/namei.h>
50 #include <linux/mount.h>
51 #include <linux/security.h>
52 #include <linux/syscalls.h>
53 #include <linux/tsacct_kern.h>
54 #include <linux/cn_proc.h>
55 #include <linux/audit.h>
56 #include <linux/tracehook.h>
57 #include <linux/kmod.h>
58 #include <linux/fsnotify.h>
59 #include <linux/fs_struct.h>
60 #include <linux/pipe_fs_i.h>
61 #include <linux/oom.h>
62 #include <linux/compat.h>
63 #include <linux/vmalloc.h>
65 #include <linux/uaccess.h>
66 #include <asm/mmu_context.h>
69 #include <trace/events/task.h>
72 #include <trace/events/sched.h>
74 int suid_dumpable
= 0;
76 static LIST_HEAD(formats
);
77 static DEFINE_RWLOCK(binfmt_lock
);
79 void __register_binfmt(struct linux_binfmt
* fmt
, int insert
)
82 if (WARN_ON(!fmt
->load_binary
))
84 write_lock(&binfmt_lock
);
85 insert
? list_add(&fmt
->lh
, &formats
) :
86 list_add_tail(&fmt
->lh
, &formats
);
87 write_unlock(&binfmt_lock
);
90 EXPORT_SYMBOL(__register_binfmt
);
92 void unregister_binfmt(struct linux_binfmt
* fmt
)
94 write_lock(&binfmt_lock
);
96 write_unlock(&binfmt_lock
);
99 EXPORT_SYMBOL(unregister_binfmt
);
101 static inline void put_binfmt(struct linux_binfmt
* fmt
)
103 module_put(fmt
->module
);
106 bool path_noexec(const struct path
*path
)
108 return (path
->mnt
->mnt_flags
& MNT_NOEXEC
) ||
109 (path
->mnt
->mnt_sb
->s_iflags
& SB_I_NOEXEC
);
114 * Note that a shared library must be both readable and executable due to
117 * Also note that we take the address to load from from the file itself.
119 SYSCALL_DEFINE1(uselib
, const char __user
*, library
)
121 struct linux_binfmt
*fmt
;
123 struct filename
*tmp
= getname(library
);
124 int error
= PTR_ERR(tmp
);
125 static const struct open_flags uselib_flags
= {
126 .open_flag
= O_LARGEFILE
| O_RDONLY
| __FMODE_EXEC
,
127 .acc_mode
= MAY_READ
| MAY_EXEC
,
128 .intent
= LOOKUP_OPEN
,
129 .lookup_flags
= LOOKUP_FOLLOW
,
135 file
= do_filp_open(AT_FDCWD
, tmp
, &uselib_flags
);
137 error
= PTR_ERR(file
);
142 if (!S_ISREG(file_inode(file
)->i_mode
))
146 if (path_noexec(&file
->f_path
))
153 read_lock(&binfmt_lock
);
154 list_for_each_entry(fmt
, &formats
, lh
) {
155 if (!fmt
->load_shlib
)
157 if (!try_module_get(fmt
->module
))
159 read_unlock(&binfmt_lock
);
160 error
= fmt
->load_shlib(file
);
161 read_lock(&binfmt_lock
);
163 if (error
!= -ENOEXEC
)
166 read_unlock(&binfmt_lock
);
172 #endif /* #ifdef CONFIG_USELIB */
176 * The nascent bprm->mm is not visible until exec_mmap() but it can
177 * use a lot of memory, account these pages in current->mm temporary
178 * for oom_badness()->get_mm_rss(). Once exec succeeds or fails, we
179 * change the counter back via acct_arg_size(0).
181 static void acct_arg_size(struct linux_binprm
*bprm
, unsigned long pages
)
183 struct mm_struct
*mm
= current
->mm
;
184 long diff
= (long)(pages
- bprm
->vma_pages
);
189 bprm
->vma_pages
= pages
;
190 add_mm_counter(mm
, MM_ANONPAGES
, diff
);
193 static struct page
*get_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
198 unsigned int gup_flags
= FOLL_FORCE
;
200 #ifdef CONFIG_STACK_GROWSUP
202 ret
= expand_downwards(bprm
->vma
, pos
);
209 gup_flags
|= FOLL_WRITE
;
212 * We are doing an exec(). 'current' is the process
213 * doing the exec and bprm->mm is the new process's mm.
215 ret
= get_user_pages_remote(current
, bprm
->mm
, pos
, 1, gup_flags
,
221 unsigned long size
= bprm
->vma
->vm_end
- bprm
->vma
->vm_start
;
224 acct_arg_size(bprm
, size
/ PAGE_SIZE
);
227 * We've historically supported up to 32 pages (ARG_MAX)
228 * of argument strings even with small stacks
234 * Limit to 1/4-th the stack size for the argv+env strings.
236 * - the remaining binfmt code will not run out of stack space,
237 * - the program will have a reasonable amount of stack left
240 rlim
= current
->signal
->rlim
;
241 if (size
> ACCESS_ONCE(rlim
[RLIMIT_STACK
].rlim_cur
) / 4) {
250 static void put_arg_page(struct page
*page
)
255 static void free_arg_pages(struct linux_binprm
*bprm
)
259 static void flush_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
262 flush_cache_page(bprm
->vma
, pos
, page_to_pfn(page
));
265 static int __bprm_mm_init(struct linux_binprm
*bprm
)
268 struct vm_area_struct
*vma
= NULL
;
269 struct mm_struct
*mm
= bprm
->mm
;
271 bprm
->vma
= vma
= kmem_cache_zalloc(vm_area_cachep
, GFP_KERNEL
);
275 if (down_write_killable(&mm
->mmap_sem
)) {
282 * Place the stack at the largest stack address the architecture
283 * supports. Later, we'll move this to an appropriate place. We don't
284 * use STACK_TOP because that can depend on attributes which aren't
287 BUILD_BUG_ON(VM_STACK_FLAGS
& VM_STACK_INCOMPLETE_SETUP
);
288 vma
->vm_end
= STACK_TOP_MAX
;
289 vma
->vm_start
= vma
->vm_end
- PAGE_SIZE
;
290 vma
->vm_flags
= VM_SOFTDIRTY
| VM_STACK_FLAGS
| VM_STACK_INCOMPLETE_SETUP
;
291 vma
->vm_page_prot
= vm_get_page_prot(vma
->vm_flags
);
292 INIT_LIST_HEAD(&vma
->anon_vma_chain
);
294 err
= insert_vm_struct(mm
, vma
);
298 mm
->stack_vm
= mm
->total_vm
= 1;
299 arch_bprm_mm_init(mm
, vma
);
300 up_write(&mm
->mmap_sem
);
301 bprm
->p
= vma
->vm_end
- sizeof(void *);
304 up_write(&mm
->mmap_sem
);
307 kmem_cache_free(vm_area_cachep
, vma
);
311 static bool valid_arg_len(struct linux_binprm
*bprm
, long len
)
313 return len
<= MAX_ARG_STRLEN
;
318 static inline void acct_arg_size(struct linux_binprm
*bprm
, unsigned long pages
)
322 static struct page
*get_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
327 page
= bprm
->page
[pos
/ PAGE_SIZE
];
328 if (!page
&& write
) {
329 page
= alloc_page(GFP_HIGHUSER
|__GFP_ZERO
);
332 bprm
->page
[pos
/ PAGE_SIZE
] = page
;
338 static void put_arg_page(struct page
*page
)
342 static void free_arg_page(struct linux_binprm
*bprm
, int i
)
345 __free_page(bprm
->page
[i
]);
346 bprm
->page
[i
] = NULL
;
350 static void free_arg_pages(struct linux_binprm
*bprm
)
354 for (i
= 0; i
< MAX_ARG_PAGES
; i
++)
355 free_arg_page(bprm
, i
);
358 static void flush_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
363 static int __bprm_mm_init(struct linux_binprm
*bprm
)
365 bprm
->p
= PAGE_SIZE
* MAX_ARG_PAGES
- sizeof(void *);
369 static bool valid_arg_len(struct linux_binprm
*bprm
, long len
)
371 return len
<= bprm
->p
;
374 #endif /* CONFIG_MMU */
377 * Create a new mm_struct and populate it with a temporary stack
378 * vm_area_struct. We don't have enough context at this point to set the stack
379 * flags, permissions, and offset, so we use temporary values. We'll update
380 * them later in setup_arg_pages().
382 static int bprm_mm_init(struct linux_binprm
*bprm
)
385 struct mm_struct
*mm
= NULL
;
387 bprm
->mm
= mm
= mm_alloc();
392 err
= __bprm_mm_init(bprm
);
407 struct user_arg_ptr
{
412 const char __user
*const __user
*native
;
414 const compat_uptr_t __user
*compat
;
419 static const char __user
*get_user_arg_ptr(struct user_arg_ptr argv
, int nr
)
421 const char __user
*native
;
424 if (unlikely(argv
.is_compat
)) {
425 compat_uptr_t compat
;
427 if (get_user(compat
, argv
.ptr
.compat
+ nr
))
428 return ERR_PTR(-EFAULT
);
430 return compat_ptr(compat
);
434 if (get_user(native
, argv
.ptr
.native
+ nr
))
435 return ERR_PTR(-EFAULT
);
441 * count() counts the number of strings in array ARGV.
443 static int count(struct user_arg_ptr argv
, int max
)
447 if (argv
.ptr
.native
!= NULL
) {
449 const char __user
*p
= get_user_arg_ptr(argv
, i
);
461 if (fatal_signal_pending(current
))
462 return -ERESTARTNOHAND
;
470 * 'copy_strings()' copies argument/environment strings from the old
471 * processes's memory to the new process's stack. The call to get_user_pages()
472 * ensures the destination page is created and not swapped out.
474 static int copy_strings(int argc
, struct user_arg_ptr argv
,
475 struct linux_binprm
*bprm
)
477 struct page
*kmapped_page
= NULL
;
479 unsigned long kpos
= 0;
483 const char __user
*str
;
488 str
= get_user_arg_ptr(argv
, argc
);
492 len
= strnlen_user(str
, MAX_ARG_STRLEN
);
497 if (!valid_arg_len(bprm
, len
))
500 /* We're going to work our way backwords. */
506 int offset
, bytes_to_copy
;
508 if (fatal_signal_pending(current
)) {
509 ret
= -ERESTARTNOHAND
;
514 offset
= pos
% PAGE_SIZE
;
518 bytes_to_copy
= offset
;
519 if (bytes_to_copy
> len
)
522 offset
-= bytes_to_copy
;
523 pos
-= bytes_to_copy
;
524 str
-= bytes_to_copy
;
525 len
-= bytes_to_copy
;
527 if (!kmapped_page
|| kpos
!= (pos
& PAGE_MASK
)) {
530 page
= get_arg_page(bprm
, pos
, 1);
537 flush_kernel_dcache_page(kmapped_page
);
538 kunmap(kmapped_page
);
539 put_arg_page(kmapped_page
);
542 kaddr
= kmap(kmapped_page
);
543 kpos
= pos
& PAGE_MASK
;
544 flush_arg_page(bprm
, kpos
, kmapped_page
);
546 if (copy_from_user(kaddr
+offset
, str
, bytes_to_copy
)) {
555 flush_kernel_dcache_page(kmapped_page
);
556 kunmap(kmapped_page
);
557 put_arg_page(kmapped_page
);
563 * Like copy_strings, but get argv and its values from kernel memory.
565 int copy_strings_kernel(int argc
, const char *const *__argv
,
566 struct linux_binprm
*bprm
)
569 mm_segment_t oldfs
= get_fs();
570 struct user_arg_ptr argv
= {
571 .ptr
.native
= (const char __user
*const __user
*)__argv
,
575 r
= copy_strings(argc
, argv
, bprm
);
580 EXPORT_SYMBOL(copy_strings_kernel
);
585 * During bprm_mm_init(), we create a temporary stack at STACK_TOP_MAX. Once
586 * the binfmt code determines where the new stack should reside, we shift it to
587 * its final location. The process proceeds as follows:
589 * 1) Use shift to calculate the new vma endpoints.
590 * 2) Extend vma to cover both the old and new ranges. This ensures the
591 * arguments passed to subsequent functions are consistent.
592 * 3) Move vma's page tables to the new range.
593 * 4) Free up any cleared pgd range.
594 * 5) Shrink the vma to cover only the new range.
596 static int shift_arg_pages(struct vm_area_struct
*vma
, unsigned long shift
)
598 struct mm_struct
*mm
= vma
->vm_mm
;
599 unsigned long old_start
= vma
->vm_start
;
600 unsigned long old_end
= vma
->vm_end
;
601 unsigned long length
= old_end
- old_start
;
602 unsigned long new_start
= old_start
- shift
;
603 unsigned long new_end
= old_end
- shift
;
604 struct mmu_gather tlb
;
606 BUG_ON(new_start
> new_end
);
609 * ensure there are no vmas between where we want to go
612 if (vma
!= find_vma(mm
, new_start
))
616 * cover the whole range: [new_start, old_end)
618 if (vma_adjust(vma
, new_start
, old_end
, vma
->vm_pgoff
, NULL
))
622 * move the page tables downwards, on failure we rely on
623 * process cleanup to remove whatever mess we made.
625 if (length
!= move_page_tables(vma
, old_start
,
626 vma
, new_start
, length
, false))
630 tlb_gather_mmu(&tlb
, mm
, old_start
, old_end
);
631 if (new_end
> old_start
) {
633 * when the old and new regions overlap clear from new_end.
635 free_pgd_range(&tlb
, new_end
, old_end
, new_end
,
636 vma
->vm_next
? vma
->vm_next
->vm_start
: USER_PGTABLES_CEILING
);
639 * otherwise, clean from old_start; this is done to not touch
640 * the address space in [new_end, old_start) some architectures
641 * have constraints on va-space that make this illegal (IA64) -
642 * for the others its just a little faster.
644 free_pgd_range(&tlb
, old_start
, old_end
, new_end
,
645 vma
->vm_next
? vma
->vm_next
->vm_start
: USER_PGTABLES_CEILING
);
647 tlb_finish_mmu(&tlb
, old_start
, old_end
);
650 * Shrink the vma to just the new range. Always succeeds.
652 vma_adjust(vma
, new_start
, new_end
, vma
->vm_pgoff
, NULL
);
658 * Finalizes the stack vm_area_struct. The flags and permissions are updated,
659 * the stack is optionally relocated, and some extra space is added.
661 int setup_arg_pages(struct linux_binprm
*bprm
,
662 unsigned long stack_top
,
663 int executable_stack
)
666 unsigned long stack_shift
;
667 struct mm_struct
*mm
= current
->mm
;
668 struct vm_area_struct
*vma
= bprm
->vma
;
669 struct vm_area_struct
*prev
= NULL
;
670 unsigned long vm_flags
;
671 unsigned long stack_base
;
672 unsigned long stack_size
;
673 unsigned long stack_expand
;
674 unsigned long rlim_stack
;
676 #ifdef CONFIG_STACK_GROWSUP
677 /* Limit stack size */
678 stack_base
= rlimit_max(RLIMIT_STACK
);
679 if (stack_base
> STACK_SIZE_MAX
)
680 stack_base
= STACK_SIZE_MAX
;
682 /* Add space for stack randomization. */
683 stack_base
+= (STACK_RND_MASK
<< PAGE_SHIFT
);
685 /* Make sure we didn't let the argument array grow too large. */
686 if (vma
->vm_end
- vma
->vm_start
> stack_base
)
689 stack_base
= PAGE_ALIGN(stack_top
- stack_base
);
691 stack_shift
= vma
->vm_start
- stack_base
;
692 mm
->arg_start
= bprm
->p
- stack_shift
;
693 bprm
->p
= vma
->vm_end
- stack_shift
;
695 stack_top
= arch_align_stack(stack_top
);
696 stack_top
= PAGE_ALIGN(stack_top
);
698 if (unlikely(stack_top
< mmap_min_addr
) ||
699 unlikely(vma
->vm_end
- vma
->vm_start
>= stack_top
- mmap_min_addr
))
702 stack_shift
= vma
->vm_end
- stack_top
;
704 bprm
->p
-= stack_shift
;
705 mm
->arg_start
= bprm
->p
;
709 bprm
->loader
-= stack_shift
;
710 bprm
->exec
-= stack_shift
;
712 if (down_write_killable(&mm
->mmap_sem
))
715 vm_flags
= VM_STACK_FLAGS
;
718 * Adjust stack execute permissions; explicitly enable for
719 * EXSTACK_ENABLE_X, disable for EXSTACK_DISABLE_X and leave alone
720 * (arch default) otherwise.
722 if (unlikely(executable_stack
== EXSTACK_ENABLE_X
))
724 else if (executable_stack
== EXSTACK_DISABLE_X
)
725 vm_flags
&= ~VM_EXEC
;
726 vm_flags
|= mm
->def_flags
;
727 vm_flags
|= VM_STACK_INCOMPLETE_SETUP
;
729 ret
= mprotect_fixup(vma
, &prev
, vma
->vm_start
, vma
->vm_end
,
735 /* Move stack pages down in memory. */
737 ret
= shift_arg_pages(vma
, stack_shift
);
742 /* mprotect_fixup is overkill to remove the temporary stack flags */
743 vma
->vm_flags
&= ~VM_STACK_INCOMPLETE_SETUP
;
745 stack_expand
= 131072UL; /* randomly 32*4k (or 2*64k) pages */
746 stack_size
= vma
->vm_end
- vma
->vm_start
;
748 * Align this down to a page boundary as expand_stack
751 rlim_stack
= rlimit(RLIMIT_STACK
) & PAGE_MASK
;
752 #ifdef CONFIG_STACK_GROWSUP
753 if (stack_size
+ stack_expand
> rlim_stack
)
754 stack_base
= vma
->vm_start
+ rlim_stack
;
756 stack_base
= vma
->vm_end
+ stack_expand
;
758 if (stack_size
+ stack_expand
> rlim_stack
)
759 stack_base
= vma
->vm_end
- rlim_stack
;
761 stack_base
= vma
->vm_start
- stack_expand
;
763 current
->mm
->start_stack
= bprm
->p
;
764 ret
= expand_stack(vma
, stack_base
);
769 up_write(&mm
->mmap_sem
);
772 EXPORT_SYMBOL(setup_arg_pages
);
777 * Transfer the program arguments and environment from the holding pages
778 * onto the stack. The provided stack pointer is adjusted accordingly.
780 int transfer_args_to_stack(struct linux_binprm
*bprm
,
781 unsigned long *sp_location
)
783 unsigned long index
, stop
, sp
;
786 stop
= bprm
->p
>> PAGE_SHIFT
;
789 for (index
= MAX_ARG_PAGES
- 1; index
>= stop
; index
--) {
790 unsigned int offset
= index
== stop
? bprm
->p
& ~PAGE_MASK
: 0;
791 char *src
= kmap(bprm
->page
[index
]) + offset
;
792 sp
-= PAGE_SIZE
- offset
;
793 if (copy_to_user((void *) sp
, src
, PAGE_SIZE
- offset
) != 0)
795 kunmap(bprm
->page
[index
]);
805 EXPORT_SYMBOL(transfer_args_to_stack
);
807 #endif /* CONFIG_MMU */
809 static struct file
*do_open_execat(int fd
, struct filename
*name
, int flags
)
813 struct open_flags open_exec_flags
= {
814 .open_flag
= O_LARGEFILE
| O_RDONLY
| __FMODE_EXEC
,
815 .acc_mode
= MAY_EXEC
,
816 .intent
= LOOKUP_OPEN
,
817 .lookup_flags
= LOOKUP_FOLLOW
,
820 if ((flags
& ~(AT_SYMLINK_NOFOLLOW
| AT_EMPTY_PATH
)) != 0)
821 return ERR_PTR(-EINVAL
);
822 if (flags
& AT_SYMLINK_NOFOLLOW
)
823 open_exec_flags
.lookup_flags
&= ~LOOKUP_FOLLOW
;
824 if (flags
& AT_EMPTY_PATH
)
825 open_exec_flags
.lookup_flags
|= LOOKUP_EMPTY
;
827 file
= do_filp_open(fd
, name
, &open_exec_flags
);
832 if (!S_ISREG(file_inode(file
)->i_mode
))
835 if (path_noexec(&file
->f_path
))
838 err
= deny_write_access(file
);
842 if (name
->name
[0] != '\0')
853 struct file
*open_exec(const char *name
)
855 struct filename
*filename
= getname_kernel(name
);
856 struct file
*f
= ERR_CAST(filename
);
858 if (!IS_ERR(filename
)) {
859 f
= do_open_execat(AT_FDCWD
, filename
, 0);
864 EXPORT_SYMBOL(open_exec
);
866 int kernel_read(struct file
*file
, loff_t offset
,
867 char *addr
, unsigned long count
)
875 /* The cast to a user pointer is valid due to the set_fs() */
876 result
= vfs_read(file
, (void __user
*)addr
, count
, &pos
);
881 EXPORT_SYMBOL(kernel_read
);
883 int kernel_read_file(struct file
*file
, void **buf
, loff_t
*size
,
884 loff_t max_size
, enum kernel_read_file_id id
)
890 if (!S_ISREG(file_inode(file
)->i_mode
) || max_size
< 0)
893 ret
= security_kernel_read_file(file
, id
);
897 ret
= deny_write_access(file
);
901 i_size
= i_size_read(file_inode(file
));
902 if (max_size
> 0 && i_size
> max_size
) {
911 if (id
!= READING_FIRMWARE_PREALLOC_BUFFER
)
912 *buf
= vmalloc(i_size
);
919 while (pos
< i_size
) {
920 bytes
= kernel_read(file
, pos
, (char *)(*buf
) + pos
,
937 ret
= security_kernel_post_read_file(file
, *buf
, i_size
, id
);
943 if (id
!= READING_FIRMWARE_PREALLOC_BUFFER
) {
950 allow_write_access(file
);
953 EXPORT_SYMBOL_GPL(kernel_read_file
);
955 int kernel_read_file_from_path(char *path
, void **buf
, loff_t
*size
,
956 loff_t max_size
, enum kernel_read_file_id id
)
964 file
= filp_open(path
, O_RDONLY
, 0);
966 return PTR_ERR(file
);
968 ret
= kernel_read_file(file
, buf
, size
, max_size
, id
);
972 EXPORT_SYMBOL_GPL(kernel_read_file_from_path
);
974 int kernel_read_file_from_fd(int fd
, void **buf
, loff_t
*size
, loff_t max_size
,
975 enum kernel_read_file_id id
)
977 struct fd f
= fdget(fd
);
983 ret
= kernel_read_file(f
.file
, buf
, size
, max_size
, id
);
988 EXPORT_SYMBOL_GPL(kernel_read_file_from_fd
);
990 ssize_t
read_code(struct file
*file
, unsigned long addr
, loff_t pos
, size_t len
)
992 ssize_t res
= vfs_read(file
, (void __user
*)addr
, len
, &pos
);
994 flush_icache_range(addr
, addr
+ len
);
997 EXPORT_SYMBOL(read_code
);
999 static int exec_mmap(struct mm_struct
*mm
)
1001 struct task_struct
*tsk
;
1002 struct mm_struct
*old_mm
, *active_mm
;
1004 /* Notify parent that we're no longer interested in the old VM */
1006 old_mm
= current
->mm
;
1007 mm_release(tsk
, old_mm
);
1010 sync_mm_rss(old_mm
);
1012 * Make sure that if there is a core dump in progress
1013 * for the old mm, we get out and die instead of going
1014 * through with the exec. We must hold mmap_sem around
1015 * checking core_state and changing tsk->mm.
1017 down_read(&old_mm
->mmap_sem
);
1018 if (unlikely(old_mm
->core_state
)) {
1019 up_read(&old_mm
->mmap_sem
);
1024 active_mm
= tsk
->active_mm
;
1026 tsk
->active_mm
= mm
;
1027 activate_mm(active_mm
, mm
);
1028 tsk
->mm
->vmacache_seqnum
= 0;
1029 vmacache_flush(tsk
);
1032 up_read(&old_mm
->mmap_sem
);
1033 BUG_ON(active_mm
!= old_mm
);
1034 setmax_mm_hiwater_rss(&tsk
->signal
->maxrss
, old_mm
);
1035 mm_update_next_owner(old_mm
);
1044 * This function makes sure the current process has its own signal table,
1045 * so that flush_signal_handlers can later reset the handlers without
1046 * disturbing other processes. (Other processes might share the signal
1047 * table via the CLONE_SIGHAND option to clone().)
1049 static int de_thread(struct task_struct
*tsk
)
1051 struct signal_struct
*sig
= tsk
->signal
;
1052 struct sighand_struct
*oldsighand
= tsk
->sighand
;
1053 spinlock_t
*lock
= &oldsighand
->siglock
;
1055 if (thread_group_empty(tsk
))
1056 goto no_thread_group
;
1059 * Kill all other threads in the thread group.
1061 spin_lock_irq(lock
);
1062 if (signal_group_exit(sig
)) {
1064 * Another group action in progress, just
1065 * return so that the signal is processed.
1067 spin_unlock_irq(lock
);
1071 sig
->group_exit_task
= tsk
;
1072 sig
->notify_count
= zap_other_threads(tsk
);
1073 if (!thread_group_leader(tsk
))
1074 sig
->notify_count
--;
1076 while (sig
->notify_count
) {
1077 __set_current_state(TASK_KILLABLE
);
1078 spin_unlock_irq(lock
);
1080 if (unlikely(__fatal_signal_pending(tsk
)))
1082 spin_lock_irq(lock
);
1084 spin_unlock_irq(lock
);
1087 * At this point all other threads have exited, all we have to
1088 * do is to wait for the thread group leader to become inactive,
1089 * and to assume its PID:
1091 if (!thread_group_leader(tsk
)) {
1092 struct task_struct
*leader
= tsk
->group_leader
;
1095 cgroup_threadgroup_change_begin(tsk
);
1096 write_lock_irq(&tasklist_lock
);
1098 * Do this under tasklist_lock to ensure that
1099 * exit_notify() can't miss ->group_exit_task
1101 sig
->notify_count
= -1;
1102 if (likely(leader
->exit_state
))
1104 __set_current_state(TASK_KILLABLE
);
1105 write_unlock_irq(&tasklist_lock
);
1106 cgroup_threadgroup_change_end(tsk
);
1108 if (unlikely(__fatal_signal_pending(tsk
)))
1113 * The only record we have of the real-time age of a
1114 * process, regardless of execs it's done, is start_time.
1115 * All the past CPU time is accumulated in signal_struct
1116 * from sister threads now dead. But in this non-leader
1117 * exec, nothing survives from the original leader thread,
1118 * whose birth marks the true age of this process now.
1119 * When we take on its identity by switching to its PID, we
1120 * also take its birthdate (always earlier than our own).
1122 tsk
->start_time
= leader
->start_time
;
1123 tsk
->real_start_time
= leader
->real_start_time
;
1125 BUG_ON(!same_thread_group(leader
, tsk
));
1126 BUG_ON(has_group_leader_pid(tsk
));
1128 * An exec() starts a new thread group with the
1129 * TGID of the previous thread group. Rehash the
1130 * two threads with a switched PID, and release
1131 * the former thread group leader:
1134 /* Become a process group leader with the old leader's pid.
1135 * The old leader becomes a thread of the this thread group.
1136 * Note: The old leader also uses this pid until release_task
1137 * is called. Odd but simple and correct.
1139 tsk
->pid
= leader
->pid
;
1140 change_pid(tsk
, PIDTYPE_PID
, task_pid(leader
));
1141 transfer_pid(leader
, tsk
, PIDTYPE_PGID
);
1142 transfer_pid(leader
, tsk
, PIDTYPE_SID
);
1144 list_replace_rcu(&leader
->tasks
, &tsk
->tasks
);
1145 list_replace_init(&leader
->sibling
, &tsk
->sibling
);
1147 tsk
->group_leader
= tsk
;
1148 leader
->group_leader
= tsk
;
1150 tsk
->exit_signal
= SIGCHLD
;
1151 leader
->exit_signal
= -1;
1153 BUG_ON(leader
->exit_state
!= EXIT_ZOMBIE
);
1154 leader
->exit_state
= EXIT_DEAD
;
1157 * We are going to release_task()->ptrace_unlink() silently,
1158 * the tracer can sleep in do_wait(). EXIT_DEAD guarantees
1159 * the tracer wont't block again waiting for this thread.
1161 if (unlikely(leader
->ptrace
))
1162 __wake_up_parent(leader
, leader
->parent
);
1163 write_unlock_irq(&tasklist_lock
);
1164 cgroup_threadgroup_change_end(tsk
);
1166 release_task(leader
);
1169 sig
->group_exit_task
= NULL
;
1170 sig
->notify_count
= 0;
1173 /* we have changed execution domain */
1174 tsk
->exit_signal
= SIGCHLD
;
1176 #ifdef CONFIG_POSIX_TIMERS
1178 flush_itimer_signals();
1181 if (atomic_read(&oldsighand
->count
) != 1) {
1182 struct sighand_struct
*newsighand
;
1184 * This ->sighand is shared with the CLONE_SIGHAND
1185 * but not CLONE_THREAD task, switch to the new one.
1187 newsighand
= kmem_cache_alloc(sighand_cachep
, GFP_KERNEL
);
1191 atomic_set(&newsighand
->count
, 1);
1192 memcpy(newsighand
->action
, oldsighand
->action
,
1193 sizeof(newsighand
->action
));
1195 write_lock_irq(&tasklist_lock
);
1196 spin_lock(&oldsighand
->siglock
);
1197 rcu_assign_pointer(tsk
->sighand
, newsighand
);
1198 spin_unlock(&oldsighand
->siglock
);
1199 write_unlock_irq(&tasklist_lock
);
1201 __cleanup_sighand(oldsighand
);
1204 BUG_ON(!thread_group_leader(tsk
));
1208 /* protects against exit_notify() and __exit_signal() */
1209 read_lock(&tasklist_lock
);
1210 sig
->group_exit_task
= NULL
;
1211 sig
->notify_count
= 0;
1212 read_unlock(&tasklist_lock
);
1216 char *get_task_comm(char *buf
, struct task_struct
*tsk
)
1218 /* buf must be at least sizeof(tsk->comm) in size */
1220 strncpy(buf
, tsk
->comm
, sizeof(tsk
->comm
));
1224 EXPORT_SYMBOL_GPL(get_task_comm
);
1227 * These functions flushes out all traces of the currently running executable
1228 * so that a new one can be started
1231 void __set_task_comm(struct task_struct
*tsk
, const char *buf
, bool exec
)
1234 trace_task_rename(tsk
, buf
);
1235 strlcpy(tsk
->comm
, buf
, sizeof(tsk
->comm
));
1237 perf_event_comm(tsk
, exec
);
1240 int flush_old_exec(struct linux_binprm
* bprm
)
1245 * Make sure we have a private signal table and that
1246 * we are unassociated from the previous thread group.
1248 retval
= de_thread(current
);
1253 * Must be called _before_ exec_mmap() as bprm->mm is
1254 * not visibile until then. This also enables the update
1257 set_mm_exe_file(bprm
->mm
, bprm
->file
);
1260 * Release all of the old mmap stuff
1262 acct_arg_size(bprm
, 0);
1263 retval
= exec_mmap(bprm
->mm
);
1267 bprm
->mm
= NULL
; /* We're using it now */
1270 current
->flags
&= ~(PF_RANDOMIZE
| PF_FORKNOEXEC
| PF_KTHREAD
|
1271 PF_NOFREEZE
| PF_NO_SETAFFINITY
);
1273 current
->personality
&= ~bprm
->per_clear
;
1276 * We have to apply CLOEXEC before we change whether the process is
1277 * dumpable (in setup_new_exec) to avoid a race with a process in userspace
1278 * trying to access the should-be-closed file descriptors of a process
1279 * undergoing exec(2).
1281 do_close_on_exec(current
->files
);
1287 EXPORT_SYMBOL(flush_old_exec
);
1289 void would_dump(struct linux_binprm
*bprm
, struct file
*file
)
1291 struct inode
*inode
= file_inode(file
);
1292 if (inode_permission(inode
, MAY_READ
) < 0) {
1293 struct user_namespace
*old
, *user_ns
;
1294 bprm
->interp_flags
|= BINPRM_FLAGS_ENFORCE_NONDUMP
;
1296 /* Ensure mm->user_ns contains the executable */
1297 user_ns
= old
= bprm
->mm
->user_ns
;
1298 while ((user_ns
!= &init_user_ns
) &&
1299 !privileged_wrt_inode_uidgid(user_ns
, inode
))
1300 user_ns
= user_ns
->parent
;
1302 if (old
!= user_ns
) {
1303 bprm
->mm
->user_ns
= get_user_ns(user_ns
);
1308 EXPORT_SYMBOL(would_dump
);
1310 void setup_new_exec(struct linux_binprm
* bprm
)
1312 arch_pick_mmap_layout(current
->mm
);
1314 /* This is the point of no return */
1315 current
->sas_ss_sp
= current
->sas_ss_size
= 0;
1317 if (uid_eq(current_euid(), current_uid()) && gid_eq(current_egid(), current_gid()))
1318 set_dumpable(current
->mm
, SUID_DUMP_USER
);
1320 set_dumpable(current
->mm
, suid_dumpable
);
1323 __set_task_comm(current
, kbasename(bprm
->filename
), true);
1325 /* Set the new mm task size. We have to do that late because it may
1326 * depend on TIF_32BIT which is only updated in flush_thread() on
1327 * some architectures like powerpc
1329 current
->mm
->task_size
= TASK_SIZE
;
1331 /* install the new credentials */
1332 if (!uid_eq(bprm
->cred
->uid
, current_euid()) ||
1333 !gid_eq(bprm
->cred
->gid
, current_egid())) {
1334 current
->pdeath_signal
= 0;
1336 if (bprm
->interp_flags
& BINPRM_FLAGS_ENFORCE_NONDUMP
)
1337 set_dumpable(current
->mm
, suid_dumpable
);
1340 /* An exec changes our domain. We are no longer part of the thread
1342 current
->self_exec_id
++;
1343 flush_signal_handlers(current
, 0);
1345 EXPORT_SYMBOL(setup_new_exec
);
1348 * Prepare credentials and lock ->cred_guard_mutex.
1349 * install_exec_creds() commits the new creds and drops the lock.
1350 * Or, if exec fails before, free_bprm() should release ->cred and
1353 int prepare_bprm_creds(struct linux_binprm
*bprm
)
1355 if (mutex_lock_interruptible(¤t
->signal
->cred_guard_mutex
))
1356 return -ERESTARTNOINTR
;
1358 bprm
->cred
= prepare_exec_creds();
1359 if (likely(bprm
->cred
))
1362 mutex_unlock(¤t
->signal
->cred_guard_mutex
);
1366 static void free_bprm(struct linux_binprm
*bprm
)
1368 free_arg_pages(bprm
);
1370 mutex_unlock(¤t
->signal
->cred_guard_mutex
);
1371 abort_creds(bprm
->cred
);
1374 allow_write_access(bprm
->file
);
1377 /* If a binfmt changed the interp, free it. */
1378 if (bprm
->interp
!= bprm
->filename
)
1379 kfree(bprm
->interp
);
1383 int bprm_change_interp(char *interp
, struct linux_binprm
*bprm
)
1385 /* If a binfmt changed the interp, free it first. */
1386 if (bprm
->interp
!= bprm
->filename
)
1387 kfree(bprm
->interp
);
1388 bprm
->interp
= kstrdup(interp
, GFP_KERNEL
);
1393 EXPORT_SYMBOL(bprm_change_interp
);
1396 * install the new credentials for this executable
1398 void install_exec_creds(struct linux_binprm
*bprm
)
1400 security_bprm_committing_creds(bprm
);
1402 commit_creds(bprm
->cred
);
1406 * Disable monitoring for regular users
1407 * when executing setuid binaries. Must
1408 * wait until new credentials are committed
1409 * by commit_creds() above
1411 if (get_dumpable(current
->mm
) != SUID_DUMP_USER
)
1412 perf_event_exit_task(current
);
1414 * cred_guard_mutex must be held at least to this point to prevent
1415 * ptrace_attach() from altering our determination of the task's
1416 * credentials; any time after this it may be unlocked.
1418 security_bprm_committed_creds(bprm
);
1419 mutex_unlock(¤t
->signal
->cred_guard_mutex
);
1421 EXPORT_SYMBOL(install_exec_creds
);
1424 * determine how safe it is to execute the proposed program
1425 * - the caller must hold ->cred_guard_mutex to protect against
1426 * PTRACE_ATTACH or seccomp thread-sync
1428 static void check_unsafe_exec(struct linux_binprm
*bprm
)
1430 struct task_struct
*p
= current
, *t
;
1434 bprm
->unsafe
|= LSM_UNSAFE_PTRACE
;
1437 * This isn't strictly necessary, but it makes it harder for LSMs to
1440 if (task_no_new_privs(current
))
1441 bprm
->unsafe
|= LSM_UNSAFE_NO_NEW_PRIVS
;
1445 spin_lock(&p
->fs
->lock
);
1447 while_each_thread(p
, t
) {
1453 if (p
->fs
->users
> n_fs
)
1454 bprm
->unsafe
|= LSM_UNSAFE_SHARE
;
1457 spin_unlock(&p
->fs
->lock
);
1460 static void bprm_fill_uid(struct linux_binprm
*bprm
)
1462 struct inode
*inode
;
1468 * Since this can be called multiple times (via prepare_binprm),
1469 * we must clear any previous work done when setting set[ug]id
1470 * bits from any earlier bprm->file uses (for example when run
1471 * first for a setuid script then again for its interpreter).
1473 bprm
->cred
->euid
= current_euid();
1474 bprm
->cred
->egid
= current_egid();
1476 if (!mnt_may_suid(bprm
->file
->f_path
.mnt
))
1479 if (task_no_new_privs(current
))
1482 inode
= bprm
->file
->f_path
.dentry
->d_inode
;
1483 mode
= READ_ONCE(inode
->i_mode
);
1484 if (!(mode
& (S_ISUID
|S_ISGID
)))
1487 /* Be careful if suid/sgid is set */
1490 /* reload atomically mode/uid/gid now that lock held */
1491 mode
= inode
->i_mode
;
1494 inode_unlock(inode
);
1496 /* We ignore suid/sgid if there are no mappings for them in the ns */
1497 if (!kuid_has_mapping(bprm
->cred
->user_ns
, uid
) ||
1498 !kgid_has_mapping(bprm
->cred
->user_ns
, gid
))
1501 if (mode
& S_ISUID
) {
1502 bprm
->per_clear
|= PER_CLEAR_ON_SETID
;
1503 bprm
->cred
->euid
= uid
;
1506 if ((mode
& (S_ISGID
| S_IXGRP
)) == (S_ISGID
| S_IXGRP
)) {
1507 bprm
->per_clear
|= PER_CLEAR_ON_SETID
;
1508 bprm
->cred
->egid
= gid
;
1513 * Fill the binprm structure from the inode.
1514 * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes
1516 * This may be called multiple times for binary chains (scripts for example).
1518 int prepare_binprm(struct linux_binprm
*bprm
)
1522 bprm_fill_uid(bprm
);
1524 /* fill in binprm security blob */
1525 retval
= security_bprm_set_creds(bprm
);
1528 bprm
->cred_prepared
= 1;
1530 memset(bprm
->buf
, 0, BINPRM_BUF_SIZE
);
1531 return kernel_read(bprm
->file
, 0, bprm
->buf
, BINPRM_BUF_SIZE
);
1534 EXPORT_SYMBOL(prepare_binprm
);
1537 * Arguments are '\0' separated strings found at the location bprm->p
1538 * points to; chop off the first by relocating brpm->p to right after
1539 * the first '\0' encountered.
1541 int remove_arg_zero(struct linux_binprm
*bprm
)
1544 unsigned long offset
;
1552 offset
= bprm
->p
& ~PAGE_MASK
;
1553 page
= get_arg_page(bprm
, bprm
->p
, 0);
1558 kaddr
= kmap_atomic(page
);
1560 for (; offset
< PAGE_SIZE
&& kaddr
[offset
];
1561 offset
++, bprm
->p
++)
1564 kunmap_atomic(kaddr
);
1566 } while (offset
== PAGE_SIZE
);
1575 EXPORT_SYMBOL(remove_arg_zero
);
1577 #define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e))
1579 * cycle the list of binary formats handler, until one recognizes the image
1581 int search_binary_handler(struct linux_binprm
*bprm
)
1583 bool need_retry
= IS_ENABLED(CONFIG_MODULES
);
1584 struct linux_binfmt
*fmt
;
1587 /* This allows 4 levels of binfmt rewrites before failing hard. */
1588 if (bprm
->recursion_depth
> 5)
1591 retval
= security_bprm_check(bprm
);
1597 read_lock(&binfmt_lock
);
1598 list_for_each_entry(fmt
, &formats
, lh
) {
1599 if (!try_module_get(fmt
->module
))
1601 read_unlock(&binfmt_lock
);
1602 bprm
->recursion_depth
++;
1603 retval
= fmt
->load_binary(bprm
);
1604 read_lock(&binfmt_lock
);
1606 bprm
->recursion_depth
--;
1607 if (retval
< 0 && !bprm
->mm
) {
1608 /* we got to flush_old_exec() and failed after it */
1609 read_unlock(&binfmt_lock
);
1610 force_sigsegv(SIGSEGV
, current
);
1613 if (retval
!= -ENOEXEC
|| !bprm
->file
) {
1614 read_unlock(&binfmt_lock
);
1618 read_unlock(&binfmt_lock
);
1621 if (printable(bprm
->buf
[0]) && printable(bprm
->buf
[1]) &&
1622 printable(bprm
->buf
[2]) && printable(bprm
->buf
[3]))
1624 if (request_module("binfmt-%04x", *(ushort
*)(bprm
->buf
+ 2)) < 0)
1632 EXPORT_SYMBOL(search_binary_handler
);
1634 static int exec_binprm(struct linux_binprm
*bprm
)
1636 pid_t old_pid
, old_vpid
;
1639 /* Need to fetch pid before load_binary changes it */
1640 old_pid
= current
->pid
;
1642 old_vpid
= task_pid_nr_ns(current
, task_active_pid_ns(current
->parent
));
1645 ret
= search_binary_handler(bprm
);
1648 trace_sched_process_exec(current
, old_pid
, bprm
);
1649 ptrace_event(PTRACE_EVENT_EXEC
, old_vpid
);
1650 proc_exec_connector(current
);
1657 * sys_execve() executes a new program.
1659 static int do_execveat_common(int fd
, struct filename
*filename
,
1660 struct user_arg_ptr argv
,
1661 struct user_arg_ptr envp
,
1664 char *pathbuf
= NULL
;
1665 struct linux_binprm
*bprm
;
1667 struct files_struct
*displaced
;
1670 if (IS_ERR(filename
))
1671 return PTR_ERR(filename
);
1674 * We move the actual failure in case of RLIMIT_NPROC excess from
1675 * set*uid() to execve() because too many poorly written programs
1676 * don't check setuid() return code. Here we additionally recheck
1677 * whether NPROC limit is still exceeded.
1679 if ((current
->flags
& PF_NPROC_EXCEEDED
) &&
1680 atomic_read(¤t_user()->processes
) > rlimit(RLIMIT_NPROC
)) {
1685 /* We're below the limit (still or again), so we don't want to make
1686 * further execve() calls fail. */
1687 current
->flags
&= ~PF_NPROC_EXCEEDED
;
1689 retval
= unshare_files(&displaced
);
1694 bprm
= kzalloc(sizeof(*bprm
), GFP_KERNEL
);
1698 retval
= prepare_bprm_creds(bprm
);
1702 check_unsafe_exec(bprm
);
1703 current
->in_execve
= 1;
1705 file
= do_open_execat(fd
, filename
, flags
);
1706 retval
= PTR_ERR(file
);
1713 if (fd
== AT_FDCWD
|| filename
->name
[0] == '/') {
1714 bprm
->filename
= filename
->name
;
1716 if (filename
->name
[0] == '\0')
1717 pathbuf
= kasprintf(GFP_TEMPORARY
, "/dev/fd/%d", fd
);
1719 pathbuf
= kasprintf(GFP_TEMPORARY
, "/dev/fd/%d/%s",
1720 fd
, filename
->name
);
1726 * Record that a name derived from an O_CLOEXEC fd will be
1727 * inaccessible after exec. Relies on having exclusive access to
1728 * current->files (due to unshare_files above).
1730 if (close_on_exec(fd
, rcu_dereference_raw(current
->files
->fdt
)))
1731 bprm
->interp_flags
|= BINPRM_FLAGS_PATH_INACCESSIBLE
;
1732 bprm
->filename
= pathbuf
;
1734 bprm
->interp
= bprm
->filename
;
1736 retval
= bprm_mm_init(bprm
);
1740 bprm
->argc
= count(argv
, MAX_ARG_STRINGS
);
1741 if ((retval
= bprm
->argc
) < 0)
1744 bprm
->envc
= count(envp
, MAX_ARG_STRINGS
);
1745 if ((retval
= bprm
->envc
) < 0)
1748 retval
= prepare_binprm(bprm
);
1752 retval
= copy_strings_kernel(1, &bprm
->filename
, bprm
);
1756 bprm
->exec
= bprm
->p
;
1757 retval
= copy_strings(bprm
->envc
, envp
, bprm
);
1761 retval
= copy_strings(bprm
->argc
, argv
, bprm
);
1765 would_dump(bprm
, bprm
->file
);
1767 retval
= exec_binprm(bprm
);
1771 /* execve succeeded */
1772 current
->fs
->in_exec
= 0;
1773 current
->in_execve
= 0;
1774 acct_update_integrals(current
);
1775 task_numa_free(current
);
1780 put_files_struct(displaced
);
1785 acct_arg_size(bprm
, 0);
1790 current
->fs
->in_exec
= 0;
1791 current
->in_execve
= 0;
1799 reset_files_struct(displaced
);
1805 int do_execve(struct filename
*filename
,
1806 const char __user
*const __user
*__argv
,
1807 const char __user
*const __user
*__envp
)
1809 struct user_arg_ptr argv
= { .ptr
.native
= __argv
};
1810 struct user_arg_ptr envp
= { .ptr
.native
= __envp
};
1811 return do_execveat_common(AT_FDCWD
, filename
, argv
, envp
, 0);
1814 int do_execveat(int fd
, struct filename
*filename
,
1815 const char __user
*const __user
*__argv
,
1816 const char __user
*const __user
*__envp
,
1819 struct user_arg_ptr argv
= { .ptr
.native
= __argv
};
1820 struct user_arg_ptr envp
= { .ptr
.native
= __envp
};
1822 return do_execveat_common(fd
, filename
, argv
, envp
, flags
);
1825 #ifdef CONFIG_COMPAT
1826 static int compat_do_execve(struct filename
*filename
,
1827 const compat_uptr_t __user
*__argv
,
1828 const compat_uptr_t __user
*__envp
)
1830 struct user_arg_ptr argv
= {
1832 .ptr
.compat
= __argv
,
1834 struct user_arg_ptr envp
= {
1836 .ptr
.compat
= __envp
,
1838 return do_execveat_common(AT_FDCWD
, filename
, argv
, envp
, 0);
1841 static int compat_do_execveat(int fd
, struct filename
*filename
,
1842 const compat_uptr_t __user
*__argv
,
1843 const compat_uptr_t __user
*__envp
,
1846 struct user_arg_ptr argv
= {
1848 .ptr
.compat
= __argv
,
1850 struct user_arg_ptr envp
= {
1852 .ptr
.compat
= __envp
,
1854 return do_execveat_common(fd
, filename
, argv
, envp
, flags
);
1858 void set_binfmt(struct linux_binfmt
*new)
1860 struct mm_struct
*mm
= current
->mm
;
1863 module_put(mm
->binfmt
->module
);
1867 __module_get(new->module
);
1869 EXPORT_SYMBOL(set_binfmt
);
1872 * set_dumpable stores three-value SUID_DUMP_* into mm->flags.
1874 void set_dumpable(struct mm_struct
*mm
, int value
)
1876 unsigned long old
, new;
1878 if (WARN_ON((unsigned)value
> SUID_DUMP_ROOT
))
1882 old
= ACCESS_ONCE(mm
->flags
);
1883 new = (old
& ~MMF_DUMPABLE_MASK
) | value
;
1884 } while (cmpxchg(&mm
->flags
, old
, new) != old
);
1887 SYSCALL_DEFINE3(execve
,
1888 const char __user
*, filename
,
1889 const char __user
*const __user
*, argv
,
1890 const char __user
*const __user
*, envp
)
1892 return do_execve(getname(filename
), argv
, envp
);
1895 SYSCALL_DEFINE5(execveat
,
1896 int, fd
, const char __user
*, filename
,
1897 const char __user
*const __user
*, argv
,
1898 const char __user
*const __user
*, envp
,
1901 int lookup_flags
= (flags
& AT_EMPTY_PATH
) ? LOOKUP_EMPTY
: 0;
1903 return do_execveat(fd
,
1904 getname_flags(filename
, lookup_flags
, NULL
),
1908 #ifdef CONFIG_COMPAT
1909 COMPAT_SYSCALL_DEFINE3(execve
, const char __user
*, filename
,
1910 const compat_uptr_t __user
*, argv
,
1911 const compat_uptr_t __user
*, envp
)
1913 return compat_do_execve(getname(filename
), argv
, envp
);
1916 COMPAT_SYSCALL_DEFINE5(execveat
, int, fd
,
1917 const char __user
*, filename
,
1918 const compat_uptr_t __user
*, argv
,
1919 const compat_uptr_t __user
*, envp
,
1922 int lookup_flags
= (flags
& AT_EMPTY_PATH
) ? LOOKUP_EMPTY
: 0;
1924 return compat_do_execveat(fd
,
1925 getname_flags(filename
, lookup_flags
, NULL
),