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/stat.h>
30 #include <linux/fcntl.h>
31 #include <linux/smp_lock.h>
32 #include <linux/swap.h>
33 #include <linux/string.h>
34 #include <linux/init.h>
35 #include <linux/pagemap.h>
36 #include <linux/perf_event.h>
37 #include <linux/highmem.h>
38 #include <linux/spinlock.h>
39 #include <linux/key.h>
40 #include <linux/personality.h>
41 #include <linux/binfmts.h>
42 #include <linux/utsname.h>
43 #include <linux/pid_namespace.h>
44 #include <linux/module.h>
45 #include <linux/namei.h>
46 #include <linux/proc_fs.h>
47 #include <linux/mount.h>
48 #include <linux/security.h>
49 #include <linux/ima.h>
50 #include <linux/syscalls.h>
51 #include <linux/tsacct_kern.h>
52 #include <linux/cn_proc.h>
53 #include <linux/audit.h>
54 #include <linux/tracehook.h>
55 #include <linux/kmod.h>
56 #include <linux/fsnotify.h>
57 #include <linux/fs_struct.h>
58 #include <linux/pipe_fs_i.h>
60 #include <asm/uaccess.h>
61 #include <asm/mmu_context.h>
66 char core_pattern
[CORENAME_MAX_SIZE
] = "core";
67 unsigned int core_pipe_limit
;
68 int suid_dumpable
= 0;
70 /* The maximal length of core_pattern is also specified in sysctl.c */
72 static LIST_HEAD(formats
);
73 static DEFINE_RWLOCK(binfmt_lock
);
75 int __register_binfmt(struct linux_binfmt
* fmt
, int insert
)
79 write_lock(&binfmt_lock
);
80 insert
? list_add(&fmt
->lh
, &formats
) :
81 list_add_tail(&fmt
->lh
, &formats
);
82 write_unlock(&binfmt_lock
);
86 EXPORT_SYMBOL(__register_binfmt
);
88 void unregister_binfmt(struct linux_binfmt
* fmt
)
90 write_lock(&binfmt_lock
);
92 write_unlock(&binfmt_lock
);
95 EXPORT_SYMBOL(unregister_binfmt
);
97 static inline void put_binfmt(struct linux_binfmt
* fmt
)
99 module_put(fmt
->module
);
103 * Note that a shared library must be both readable and executable due to
106 * Also note that we take the address to load from from the file itself.
108 SYSCALL_DEFINE1(uselib
, const char __user
*, library
)
111 char *tmp
= getname(library
);
112 int error
= PTR_ERR(tmp
);
117 file
= do_filp_open(AT_FDCWD
, tmp
,
118 O_LARGEFILE
| O_RDONLY
| FMODE_EXEC
, 0,
119 MAY_READ
| MAY_EXEC
| MAY_OPEN
);
121 error
= PTR_ERR(file
);
126 if (!S_ISREG(file
->f_path
.dentry
->d_inode
->i_mode
))
130 if (file
->f_path
.mnt
->mnt_flags
& MNT_NOEXEC
)
133 fsnotify_open(file
->f_path
.dentry
);
137 struct linux_binfmt
* fmt
;
139 read_lock(&binfmt_lock
);
140 list_for_each_entry(fmt
, &formats
, lh
) {
141 if (!fmt
->load_shlib
)
143 if (!try_module_get(fmt
->module
))
145 read_unlock(&binfmt_lock
);
146 error
= fmt
->load_shlib(file
);
147 read_lock(&binfmt_lock
);
149 if (error
!= -ENOEXEC
)
152 read_unlock(&binfmt_lock
);
162 static struct page
*get_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
168 #ifdef CONFIG_STACK_GROWSUP
170 ret
= expand_stack_downwards(bprm
->vma
, pos
);
175 ret
= get_user_pages(current
, bprm
->mm
, pos
,
176 1, write
, 1, &page
, NULL
);
181 unsigned long size
= bprm
->vma
->vm_end
- bprm
->vma
->vm_start
;
185 * We've historically supported up to 32 pages (ARG_MAX)
186 * of argument strings even with small stacks
192 * Limit to 1/4-th the stack size for the argv+env strings.
194 * - the remaining binfmt code will not run out of stack space,
195 * - the program will have a reasonable amount of stack left
198 rlim
= current
->signal
->rlim
;
199 if (size
> rlim
[RLIMIT_STACK
].rlim_cur
/ 4) {
208 static void put_arg_page(struct page
*page
)
213 static void free_arg_page(struct linux_binprm
*bprm
, int i
)
217 static void free_arg_pages(struct linux_binprm
*bprm
)
221 static void flush_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
224 flush_cache_page(bprm
->vma
, pos
, page_to_pfn(page
));
227 static int __bprm_mm_init(struct linux_binprm
*bprm
)
230 struct vm_area_struct
*vma
= NULL
;
231 struct mm_struct
*mm
= bprm
->mm
;
233 bprm
->vma
= vma
= kmem_cache_zalloc(vm_area_cachep
, GFP_KERNEL
);
237 down_write(&mm
->mmap_sem
);
241 * Place the stack at the largest stack address the architecture
242 * supports. Later, we'll move this to an appropriate place. We don't
243 * use STACK_TOP because that can depend on attributes which aren't
246 vma
->vm_end
= STACK_TOP_MAX
;
247 vma
->vm_start
= vma
->vm_end
- PAGE_SIZE
;
248 vma
->vm_flags
= VM_STACK_FLAGS
;
249 vma
->vm_page_prot
= vm_get_page_prot(vma
->vm_flags
);
251 err
= security_file_mmap(NULL
, 0, 0, 0, vma
->vm_start
, 1);
255 err
= insert_vm_struct(mm
, vma
);
259 mm
->stack_vm
= mm
->total_vm
= 1;
260 up_write(&mm
->mmap_sem
);
261 bprm
->p
= vma
->vm_end
- sizeof(void *);
264 up_write(&mm
->mmap_sem
);
266 kmem_cache_free(vm_area_cachep
, vma
);
270 static bool valid_arg_len(struct linux_binprm
*bprm
, long len
)
272 return len
<= MAX_ARG_STRLEN
;
277 static struct page
*get_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
282 page
= bprm
->page
[pos
/ PAGE_SIZE
];
283 if (!page
&& write
) {
284 page
= alloc_page(GFP_HIGHUSER
|__GFP_ZERO
);
287 bprm
->page
[pos
/ PAGE_SIZE
] = page
;
293 static void put_arg_page(struct page
*page
)
297 static void free_arg_page(struct linux_binprm
*bprm
, int i
)
300 __free_page(bprm
->page
[i
]);
301 bprm
->page
[i
] = NULL
;
305 static void free_arg_pages(struct linux_binprm
*bprm
)
309 for (i
= 0; i
< MAX_ARG_PAGES
; i
++)
310 free_arg_page(bprm
, i
);
313 static void flush_arg_page(struct linux_binprm
*bprm
, unsigned long pos
,
318 static int __bprm_mm_init(struct linux_binprm
*bprm
)
320 bprm
->p
= PAGE_SIZE
* MAX_ARG_PAGES
- sizeof(void *);
324 static bool valid_arg_len(struct linux_binprm
*bprm
, long len
)
326 return len
<= bprm
->p
;
329 #endif /* CONFIG_MMU */
332 * Create a new mm_struct and populate it with a temporary stack
333 * vm_area_struct. We don't have enough context at this point to set the stack
334 * flags, permissions, and offset, so we use temporary values. We'll update
335 * them later in setup_arg_pages().
337 int bprm_mm_init(struct linux_binprm
*bprm
)
340 struct mm_struct
*mm
= NULL
;
342 bprm
->mm
= mm
= mm_alloc();
347 err
= init_new_context(current
, mm
);
351 err
= __bprm_mm_init(bprm
);
367 * count() counts the number of strings in array ARGV.
369 static int count(char __user
* __user
* argv
, int max
)
377 if (get_user(p
, argv
))
385 if (fatal_signal_pending(current
))
386 return -ERESTARTNOHAND
;
394 * 'copy_strings()' copies argument/environment strings from the old
395 * processes's memory to the new process's stack. The call to get_user_pages()
396 * ensures the destination page is created and not swapped out.
398 static int copy_strings(int argc
, char __user
* __user
* argv
,
399 struct linux_binprm
*bprm
)
401 struct page
*kmapped_page
= NULL
;
403 unsigned long kpos
= 0;
411 if (get_user(str
, argv
+argc
) ||
412 !(len
= strnlen_user(str
, MAX_ARG_STRLEN
))) {
417 if (!valid_arg_len(bprm
, len
)) {
422 /* We're going to work our way backwords. */
428 int offset
, bytes_to_copy
;
430 if (fatal_signal_pending(current
)) {
431 ret
= -ERESTARTNOHAND
;
436 offset
= pos
% PAGE_SIZE
;
440 bytes_to_copy
= offset
;
441 if (bytes_to_copy
> len
)
444 offset
-= bytes_to_copy
;
445 pos
-= bytes_to_copy
;
446 str
-= bytes_to_copy
;
447 len
-= bytes_to_copy
;
449 if (!kmapped_page
|| kpos
!= (pos
& PAGE_MASK
)) {
452 page
= get_arg_page(bprm
, pos
, 1);
459 flush_kernel_dcache_page(kmapped_page
);
460 kunmap(kmapped_page
);
461 put_arg_page(kmapped_page
);
464 kaddr
= kmap(kmapped_page
);
465 kpos
= pos
& PAGE_MASK
;
466 flush_arg_page(bprm
, kpos
, kmapped_page
);
468 if (copy_from_user(kaddr
+offset
, str
, bytes_to_copy
)) {
477 flush_kernel_dcache_page(kmapped_page
);
478 kunmap(kmapped_page
);
479 put_arg_page(kmapped_page
);
485 * Like copy_strings, but get argv and its values from kernel memory.
487 int copy_strings_kernel(int argc
,char ** argv
, struct linux_binprm
*bprm
)
490 mm_segment_t oldfs
= get_fs();
492 r
= copy_strings(argc
, (char __user
* __user
*)argv
, bprm
);
496 EXPORT_SYMBOL(copy_strings_kernel
);
501 * During bprm_mm_init(), we create a temporary stack at STACK_TOP_MAX. Once
502 * the binfmt code determines where the new stack should reside, we shift it to
503 * its final location. The process proceeds as follows:
505 * 1) Use shift to calculate the new vma endpoints.
506 * 2) Extend vma to cover both the old and new ranges. This ensures the
507 * arguments passed to subsequent functions are consistent.
508 * 3) Move vma's page tables to the new range.
509 * 4) Free up any cleared pgd range.
510 * 5) Shrink the vma to cover only the new range.
512 static int shift_arg_pages(struct vm_area_struct
*vma
, unsigned long shift
)
514 struct mm_struct
*mm
= vma
->vm_mm
;
515 unsigned long old_start
= vma
->vm_start
;
516 unsigned long old_end
= vma
->vm_end
;
517 unsigned long length
= old_end
- old_start
;
518 unsigned long new_start
= old_start
- shift
;
519 unsigned long new_end
= old_end
- shift
;
520 struct mmu_gather
*tlb
;
522 BUG_ON(new_start
> new_end
);
525 * ensure there are no vmas between where we want to go
528 if (vma
!= find_vma(mm
, new_start
))
532 * cover the whole range: [new_start, old_end)
534 vma_adjust(vma
, new_start
, old_end
, vma
->vm_pgoff
, NULL
);
537 * move the page tables downwards, on failure we rely on
538 * process cleanup to remove whatever mess we made.
540 if (length
!= move_page_tables(vma
, old_start
,
541 vma
, new_start
, length
))
545 tlb
= tlb_gather_mmu(mm
, 0);
546 if (new_end
> old_start
) {
548 * when the old and new regions overlap clear from new_end.
550 free_pgd_range(tlb
, new_end
, old_end
, new_end
,
551 vma
->vm_next
? vma
->vm_next
->vm_start
: 0);
554 * otherwise, clean from old_start; this is done to not touch
555 * the address space in [new_end, old_start) some architectures
556 * have constraints on va-space that make this illegal (IA64) -
557 * for the others its just a little faster.
559 free_pgd_range(tlb
, old_start
, old_end
, new_end
,
560 vma
->vm_next
? vma
->vm_next
->vm_start
: 0);
562 tlb_finish_mmu(tlb
, new_end
, old_end
);
565 * shrink the vma to just the new range.
567 vma_adjust(vma
, new_start
, new_end
, vma
->vm_pgoff
, NULL
);
572 #define EXTRA_STACK_VM_PAGES 20 /* random */
575 * Finalizes the stack vm_area_struct. The flags and permissions are updated,
576 * the stack is optionally relocated, and some extra space is added.
578 int setup_arg_pages(struct linux_binprm
*bprm
,
579 unsigned long stack_top
,
580 int executable_stack
)
583 unsigned long stack_shift
;
584 struct mm_struct
*mm
= current
->mm
;
585 struct vm_area_struct
*vma
= bprm
->vma
;
586 struct vm_area_struct
*prev
= NULL
;
587 unsigned long vm_flags
;
588 unsigned long stack_base
;
589 unsigned long stack_size
;
590 unsigned long stack_expand
;
591 unsigned long rlim_stack
;
593 #ifdef CONFIG_STACK_GROWSUP
594 /* Limit stack size to 1GB */
595 stack_base
= current
->signal
->rlim
[RLIMIT_STACK
].rlim_max
;
596 if (stack_base
> (1 << 30))
597 stack_base
= 1 << 30;
599 /* Make sure we didn't let the argument array grow too large. */
600 if (vma
->vm_end
- vma
->vm_start
> stack_base
)
603 stack_base
= PAGE_ALIGN(stack_top
- stack_base
);
605 stack_shift
= vma
->vm_start
- stack_base
;
606 mm
->arg_start
= bprm
->p
- stack_shift
;
607 bprm
->p
= vma
->vm_end
- stack_shift
;
609 stack_top
= arch_align_stack(stack_top
);
610 stack_top
= PAGE_ALIGN(stack_top
);
612 if (unlikely(stack_top
< mmap_min_addr
) ||
613 unlikely(vma
->vm_end
- vma
->vm_start
>= stack_top
- mmap_min_addr
))
616 stack_shift
= vma
->vm_end
- stack_top
;
618 bprm
->p
-= stack_shift
;
619 mm
->arg_start
= bprm
->p
;
623 bprm
->loader
-= stack_shift
;
624 bprm
->exec
-= stack_shift
;
626 down_write(&mm
->mmap_sem
);
627 vm_flags
= VM_STACK_FLAGS
;
630 * Adjust stack execute permissions; explicitly enable for
631 * EXSTACK_ENABLE_X, disable for EXSTACK_DISABLE_X and leave alone
632 * (arch default) otherwise.
634 if (unlikely(executable_stack
== EXSTACK_ENABLE_X
))
636 else if (executable_stack
== EXSTACK_DISABLE_X
)
637 vm_flags
&= ~VM_EXEC
;
638 vm_flags
|= mm
->def_flags
;
640 ret
= mprotect_fixup(vma
, &prev
, vma
->vm_start
, vma
->vm_end
,
646 /* Move stack pages down in memory. */
648 ret
= shift_arg_pages(vma
, stack_shift
);
653 stack_expand
= EXTRA_STACK_VM_PAGES
* PAGE_SIZE
;
654 stack_size
= vma
->vm_end
- vma
->vm_start
;
656 * Align this down to a page boundary as expand_stack
659 rlim_stack
= rlimit(RLIMIT_STACK
) & PAGE_MASK
;
660 #ifdef CONFIG_STACK_GROWSUP
661 if (stack_size
+ stack_expand
> rlim_stack
)
662 stack_base
= vma
->vm_start
+ rlim_stack
;
664 stack_base
= vma
->vm_end
+ stack_expand
;
666 if (stack_size
+ stack_expand
> rlim_stack
)
667 stack_base
= vma
->vm_end
- rlim_stack
;
669 stack_base
= vma
->vm_start
- stack_expand
;
671 ret
= expand_stack(vma
, stack_base
);
676 up_write(&mm
->mmap_sem
);
679 EXPORT_SYMBOL(setup_arg_pages
);
681 #endif /* CONFIG_MMU */
683 struct file
*open_exec(const char *name
)
688 file
= do_filp_open(AT_FDCWD
, name
,
689 O_LARGEFILE
| O_RDONLY
| FMODE_EXEC
, 0,
690 MAY_EXEC
| MAY_OPEN
);
695 if (!S_ISREG(file
->f_path
.dentry
->d_inode
->i_mode
))
698 if (file
->f_path
.mnt
->mnt_flags
& MNT_NOEXEC
)
701 fsnotify_open(file
->f_path
.dentry
);
703 err
= deny_write_access(file
);
714 EXPORT_SYMBOL(open_exec
);
716 int kernel_read(struct file
*file
, loff_t offset
,
717 char *addr
, unsigned long count
)
725 /* The cast to a user pointer is valid due to the set_fs() */
726 result
= vfs_read(file
, (void __user
*)addr
, count
, &pos
);
731 EXPORT_SYMBOL(kernel_read
);
733 static int exec_mmap(struct mm_struct
*mm
)
735 struct task_struct
*tsk
;
736 struct mm_struct
* old_mm
, *active_mm
;
738 /* Notify parent that we're no longer interested in the old VM */
740 old_mm
= current
->mm
;
741 mm_release(tsk
, old_mm
);
745 * Make sure that if there is a core dump in progress
746 * for the old mm, we get out and die instead of going
747 * through with the exec. We must hold mmap_sem around
748 * checking core_state and changing tsk->mm.
750 down_read(&old_mm
->mmap_sem
);
751 if (unlikely(old_mm
->core_state
)) {
752 up_read(&old_mm
->mmap_sem
);
757 active_mm
= tsk
->active_mm
;
760 activate_mm(active_mm
, mm
);
762 arch_pick_mmap_layout(mm
);
764 up_read(&old_mm
->mmap_sem
);
765 BUG_ON(active_mm
!= old_mm
);
766 mm_update_next_owner(old_mm
);
775 * This function makes sure the current process has its own signal table,
776 * so that flush_signal_handlers can later reset the handlers without
777 * disturbing other processes. (Other processes might share the signal
778 * table via the CLONE_SIGHAND option to clone().)
780 static int de_thread(struct task_struct
*tsk
)
782 struct signal_struct
*sig
= tsk
->signal
;
783 struct sighand_struct
*oldsighand
= tsk
->sighand
;
784 spinlock_t
*lock
= &oldsighand
->siglock
;
787 if (thread_group_empty(tsk
))
788 goto no_thread_group
;
791 * Kill all other threads in the thread group.
794 if (signal_group_exit(sig
)) {
796 * Another group action in progress, just
797 * return so that the signal is processed.
799 spin_unlock_irq(lock
);
802 sig
->group_exit_task
= tsk
;
803 zap_other_threads(tsk
);
805 /* Account for the thread group leader hanging around: */
806 count
= thread_group_leader(tsk
) ? 1 : 2;
807 sig
->notify_count
= count
;
808 while (atomic_read(&sig
->count
) > count
) {
809 __set_current_state(TASK_UNINTERRUPTIBLE
);
810 spin_unlock_irq(lock
);
814 spin_unlock_irq(lock
);
817 * At this point all other threads have exited, all we have to
818 * do is to wait for the thread group leader to become inactive,
819 * and to assume its PID:
821 if (!thread_group_leader(tsk
)) {
822 struct task_struct
*leader
= tsk
->group_leader
;
824 sig
->notify_count
= -1; /* for exit_notify() */
826 write_lock_irq(&tasklist_lock
);
827 if (likely(leader
->exit_state
))
829 __set_current_state(TASK_UNINTERRUPTIBLE
);
830 write_unlock_irq(&tasklist_lock
);
835 * The only record we have of the real-time age of a
836 * process, regardless of execs it's done, is start_time.
837 * All the past CPU time is accumulated in signal_struct
838 * from sister threads now dead. But in this non-leader
839 * exec, nothing survives from the original leader thread,
840 * whose birth marks the true age of this process now.
841 * When we take on its identity by switching to its PID, we
842 * also take its birthdate (always earlier than our own).
844 tsk
->start_time
= leader
->start_time
;
846 BUG_ON(!same_thread_group(leader
, tsk
));
847 BUG_ON(has_group_leader_pid(tsk
));
849 * An exec() starts a new thread group with the
850 * TGID of the previous thread group. Rehash the
851 * two threads with a switched PID, and release
852 * the former thread group leader:
855 /* Become a process group leader with the old leader's pid.
856 * The old leader becomes a thread of the this thread group.
857 * Note: The old leader also uses this pid until release_task
858 * is called. Odd but simple and correct.
860 detach_pid(tsk
, PIDTYPE_PID
);
861 tsk
->pid
= leader
->pid
;
862 attach_pid(tsk
, PIDTYPE_PID
, task_pid(leader
));
863 transfer_pid(leader
, tsk
, PIDTYPE_PGID
);
864 transfer_pid(leader
, tsk
, PIDTYPE_SID
);
865 list_replace_rcu(&leader
->tasks
, &tsk
->tasks
);
867 tsk
->group_leader
= tsk
;
868 leader
->group_leader
= tsk
;
870 tsk
->exit_signal
= SIGCHLD
;
872 BUG_ON(leader
->exit_state
!= EXIT_ZOMBIE
);
873 leader
->exit_state
= EXIT_DEAD
;
874 write_unlock_irq(&tasklist_lock
);
876 release_task(leader
);
879 sig
->group_exit_task
= NULL
;
880 sig
->notify_count
= 0;
884 setmax_mm_hiwater_rss(&sig
->maxrss
, current
->mm
);
887 flush_itimer_signals();
889 if (atomic_read(&oldsighand
->count
) != 1) {
890 struct sighand_struct
*newsighand
;
892 * This ->sighand is shared with the CLONE_SIGHAND
893 * but not CLONE_THREAD task, switch to the new one.
895 newsighand
= kmem_cache_alloc(sighand_cachep
, GFP_KERNEL
);
899 atomic_set(&newsighand
->count
, 1);
900 memcpy(newsighand
->action
, oldsighand
->action
,
901 sizeof(newsighand
->action
));
903 write_lock_irq(&tasklist_lock
);
904 spin_lock(&oldsighand
->siglock
);
905 rcu_assign_pointer(tsk
->sighand
, newsighand
);
906 spin_unlock(&oldsighand
->siglock
);
907 write_unlock_irq(&tasklist_lock
);
909 __cleanup_sighand(oldsighand
);
912 BUG_ON(!thread_group_leader(tsk
));
917 * These functions flushes out all traces of the currently running executable
918 * so that a new one can be started
920 static void flush_old_files(struct files_struct
* files
)
925 spin_lock(&files
->file_lock
);
927 unsigned long set
, i
;
931 fdt
= files_fdtable(files
);
932 if (i
>= fdt
->max_fds
)
934 set
= fdt
->close_on_exec
->fds_bits
[j
];
937 fdt
->close_on_exec
->fds_bits
[j
] = 0;
938 spin_unlock(&files
->file_lock
);
939 for ( ; set
; i
++,set
>>= 1) {
944 spin_lock(&files
->file_lock
);
947 spin_unlock(&files
->file_lock
);
950 char *get_task_comm(char *buf
, struct task_struct
*tsk
)
952 /* buf must be at least sizeof(tsk->comm) in size */
954 strncpy(buf
, tsk
->comm
, sizeof(tsk
->comm
));
959 void set_task_comm(struct task_struct
*tsk
, char *buf
)
962 strlcpy(tsk
->comm
, buf
, sizeof(tsk
->comm
));
964 perf_event_comm(tsk
);
967 int flush_old_exec(struct linux_binprm
* bprm
)
972 * Make sure we have a private signal table and that
973 * we are unassociated from the previous thread group.
975 retval
= de_thread(current
);
979 set_mm_exe_file(bprm
->mm
, bprm
->file
);
982 * Release all of the old mmap stuff
984 retval
= exec_mmap(bprm
->mm
);
988 bprm
->mm
= NULL
; /* We're using it now */
990 current
->flags
&= ~PF_RANDOMIZE
;
992 current
->personality
&= ~bprm
->per_clear
;
999 EXPORT_SYMBOL(flush_old_exec
);
1001 void setup_new_exec(struct linux_binprm
* bprm
)
1005 char tcomm
[sizeof(current
->comm
)];
1007 arch_pick_mmap_layout(current
->mm
);
1009 /* This is the point of no return */
1010 current
->sas_ss_sp
= current
->sas_ss_size
= 0;
1012 if (current_euid() == current_uid() && current_egid() == current_gid())
1013 set_dumpable(current
->mm
, 1);
1015 set_dumpable(current
->mm
, suid_dumpable
);
1017 name
= bprm
->filename
;
1019 /* Copies the binary name from after last slash */
1020 for (i
=0; (ch
= *(name
++)) != '\0';) {
1022 i
= 0; /* overwrite what we wrote */
1024 if (i
< (sizeof(tcomm
) - 1))
1028 set_task_comm(current
, tcomm
);
1030 /* Set the new mm task size. We have to do that late because it may
1031 * depend on TIF_32BIT which is only updated in flush_thread() on
1032 * some architectures like powerpc
1034 current
->mm
->task_size
= TASK_SIZE
;
1036 /* install the new credentials */
1037 if (bprm
->cred
->uid
!= current_euid() ||
1038 bprm
->cred
->gid
!= current_egid()) {
1039 current
->pdeath_signal
= 0;
1040 } else if (file_permission(bprm
->file
, MAY_READ
) ||
1041 bprm
->interp_flags
& BINPRM_FLAGS_ENFORCE_NONDUMP
) {
1042 set_dumpable(current
->mm
, suid_dumpable
);
1046 * Flush performance counters when crossing a
1049 if (!get_dumpable(current
->mm
))
1050 perf_event_exit_task(current
);
1052 /* An exec changes our domain. We are no longer part of the thread
1055 current
->self_exec_id
++;
1057 flush_signal_handlers(current
, 0);
1058 flush_old_files(current
->files
);
1060 EXPORT_SYMBOL(setup_new_exec
);
1063 * Prepare credentials and lock ->cred_guard_mutex.
1064 * install_exec_creds() commits the new creds and drops the lock.
1065 * Or, if exec fails before, free_bprm() should release ->cred and
1068 int prepare_bprm_creds(struct linux_binprm
*bprm
)
1070 if (mutex_lock_interruptible(¤t
->cred_guard_mutex
))
1071 return -ERESTARTNOINTR
;
1073 bprm
->cred
= prepare_exec_creds();
1074 if (likely(bprm
->cred
))
1077 mutex_unlock(¤t
->cred_guard_mutex
);
1081 void free_bprm(struct linux_binprm
*bprm
)
1083 free_arg_pages(bprm
);
1085 mutex_unlock(¤t
->cred_guard_mutex
);
1086 abort_creds(bprm
->cred
);
1092 * install the new credentials for this executable
1094 void install_exec_creds(struct linux_binprm
*bprm
)
1096 security_bprm_committing_creds(bprm
);
1098 commit_creds(bprm
->cred
);
1101 * cred_guard_mutex must be held at least to this point to prevent
1102 * ptrace_attach() from altering our determination of the task's
1103 * credentials; any time after this it may be unlocked.
1105 security_bprm_committed_creds(bprm
);
1106 mutex_unlock(¤t
->cred_guard_mutex
);
1108 EXPORT_SYMBOL(install_exec_creds
);
1111 * determine how safe it is to execute the proposed program
1112 * - the caller must hold current->cred_guard_mutex to protect against
1115 int check_unsafe_exec(struct linux_binprm
*bprm
)
1117 struct task_struct
*p
= current
, *t
;
1121 bprm
->unsafe
= tracehook_unsafe_exec(p
);
1124 write_lock(&p
->fs
->lock
);
1126 for (t
= next_thread(p
); t
!= p
; t
= next_thread(t
)) {
1132 if (p
->fs
->users
> n_fs
) {
1133 bprm
->unsafe
|= LSM_UNSAFE_SHARE
;
1136 if (!p
->fs
->in_exec
) {
1141 write_unlock(&p
->fs
->lock
);
1147 * Fill the binprm structure from the inode.
1148 * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes
1150 * This may be called multiple times for binary chains (scripts for example).
1152 int prepare_binprm(struct linux_binprm
*bprm
)
1155 struct inode
* inode
= bprm
->file
->f_path
.dentry
->d_inode
;
1158 mode
= inode
->i_mode
;
1159 if (bprm
->file
->f_op
== NULL
)
1162 /* clear any previous set[ug]id data from a previous binary */
1163 bprm
->cred
->euid
= current_euid();
1164 bprm
->cred
->egid
= current_egid();
1166 if (!(bprm
->file
->f_path
.mnt
->mnt_flags
& MNT_NOSUID
)) {
1168 if (mode
& S_ISUID
) {
1169 bprm
->per_clear
|= PER_CLEAR_ON_SETID
;
1170 bprm
->cred
->euid
= inode
->i_uid
;
1175 * If setgid is set but no group execute bit then this
1176 * is a candidate for mandatory locking, not a setgid
1179 if ((mode
& (S_ISGID
| S_IXGRP
)) == (S_ISGID
| S_IXGRP
)) {
1180 bprm
->per_clear
|= PER_CLEAR_ON_SETID
;
1181 bprm
->cred
->egid
= inode
->i_gid
;
1185 /* fill in binprm security blob */
1186 retval
= security_bprm_set_creds(bprm
);
1189 bprm
->cred_prepared
= 1;
1191 memset(bprm
->buf
, 0, BINPRM_BUF_SIZE
);
1192 return kernel_read(bprm
->file
, 0, bprm
->buf
, BINPRM_BUF_SIZE
);
1195 EXPORT_SYMBOL(prepare_binprm
);
1198 * Arguments are '\0' separated strings found at the location bprm->p
1199 * points to; chop off the first by relocating brpm->p to right after
1200 * the first '\0' encountered.
1202 int remove_arg_zero(struct linux_binprm
*bprm
)
1205 unsigned long offset
;
1213 offset
= bprm
->p
& ~PAGE_MASK
;
1214 page
= get_arg_page(bprm
, bprm
->p
, 0);
1219 kaddr
= kmap_atomic(page
, KM_USER0
);
1221 for (; offset
< PAGE_SIZE
&& kaddr
[offset
];
1222 offset
++, bprm
->p
++)
1225 kunmap_atomic(kaddr
, KM_USER0
);
1228 if (offset
== PAGE_SIZE
)
1229 free_arg_page(bprm
, (bprm
->p
>> PAGE_SHIFT
) - 1);
1230 } while (offset
== PAGE_SIZE
);
1239 EXPORT_SYMBOL(remove_arg_zero
);
1242 * cycle the list of binary formats handler, until one recognizes the image
1244 int search_binary_handler(struct linux_binprm
*bprm
,struct pt_regs
*regs
)
1246 unsigned int depth
= bprm
->recursion_depth
;
1248 struct linux_binfmt
*fmt
;
1250 retval
= security_bprm_check(bprm
);
1253 retval
= ima_bprm_check(bprm
);
1257 /* kernel module loader fixup */
1258 /* so we don't try to load run modprobe in kernel space. */
1261 retval
= audit_bprm(bprm
);
1266 for (try=0; try<2; try++) {
1267 read_lock(&binfmt_lock
);
1268 list_for_each_entry(fmt
, &formats
, lh
) {
1269 int (*fn
)(struct linux_binprm
*, struct pt_regs
*) = fmt
->load_binary
;
1272 if (!try_module_get(fmt
->module
))
1274 read_unlock(&binfmt_lock
);
1275 retval
= fn(bprm
, regs
);
1277 * Restore the depth counter to its starting value
1278 * in this call, so we don't have to rely on every
1279 * load_binary function to restore it on return.
1281 bprm
->recursion_depth
= depth
;
1284 tracehook_report_exec(fmt
, bprm
, regs
);
1286 allow_write_access(bprm
->file
);
1290 current
->did_exec
= 1;
1291 proc_exec_connector(current
);
1294 read_lock(&binfmt_lock
);
1296 if (retval
!= -ENOEXEC
|| bprm
->mm
== NULL
)
1299 read_unlock(&binfmt_lock
);
1303 read_unlock(&binfmt_lock
);
1304 if (retval
!= -ENOEXEC
|| bprm
->mm
== NULL
) {
1306 #ifdef CONFIG_MODULES
1308 #define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e))
1309 if (printable(bprm
->buf
[0]) &&
1310 printable(bprm
->buf
[1]) &&
1311 printable(bprm
->buf
[2]) &&
1312 printable(bprm
->buf
[3]))
1313 break; /* -ENOEXEC */
1314 request_module("binfmt-%04x", *(unsigned short *)(&bprm
->buf
[2]));
1321 EXPORT_SYMBOL(search_binary_handler
);
1324 * sys_execve() executes a new program.
1326 int do_execve(char * filename
,
1327 char __user
*__user
*argv
,
1328 char __user
*__user
*envp
,
1329 struct pt_regs
* regs
)
1331 struct linux_binprm
*bprm
;
1333 struct files_struct
*displaced
;
1337 retval
= unshare_files(&displaced
);
1342 bprm
= kzalloc(sizeof(*bprm
), GFP_KERNEL
);
1346 retval
= prepare_bprm_creds(bprm
);
1350 retval
= check_unsafe_exec(bprm
);
1353 clear_in_exec
= retval
;
1354 current
->in_execve
= 1;
1356 file
= open_exec(filename
);
1357 retval
= PTR_ERR(file
);
1364 bprm
->filename
= filename
;
1365 bprm
->interp
= filename
;
1367 retval
= bprm_mm_init(bprm
);
1371 bprm
->argc
= count(argv
, MAX_ARG_STRINGS
);
1372 if ((retval
= bprm
->argc
) < 0)
1375 bprm
->envc
= count(envp
, MAX_ARG_STRINGS
);
1376 if ((retval
= bprm
->envc
) < 0)
1379 retval
= prepare_binprm(bprm
);
1383 retval
= copy_strings_kernel(1, &bprm
->filename
, bprm
);
1387 bprm
->exec
= bprm
->p
;
1388 retval
= copy_strings(bprm
->envc
, envp
, bprm
);
1392 retval
= copy_strings(bprm
->argc
, argv
, bprm
);
1396 current
->flags
&= ~PF_KTHREAD
;
1397 retval
= search_binary_handler(bprm
,regs
);
1401 /* execve succeeded */
1402 current
->fs
->in_exec
= 0;
1403 current
->in_execve
= 0;
1404 acct_update_integrals(current
);
1407 put_files_struct(displaced
);
1416 allow_write_access(bprm
->file
);
1422 current
->fs
->in_exec
= 0;
1423 current
->in_execve
= 0;
1430 reset_files_struct(displaced
);
1435 void set_binfmt(struct linux_binfmt
*new)
1437 struct mm_struct
*mm
= current
->mm
;
1440 module_put(mm
->binfmt
->module
);
1444 __module_get(new->module
);
1447 EXPORT_SYMBOL(set_binfmt
);
1449 /* format_corename will inspect the pattern parameter, and output a
1450 * name into corename, which must have space for at least
1451 * CORENAME_MAX_SIZE bytes plus one byte for the zero terminator.
1453 static int format_corename(char *corename
, long signr
)
1455 const struct cred
*cred
= current_cred();
1456 const char *pat_ptr
= core_pattern
;
1457 int ispipe
= (*pat_ptr
== '|');
1458 char *out_ptr
= corename
;
1459 char *const out_end
= corename
+ CORENAME_MAX_SIZE
;
1461 int pid_in_pattern
= 0;
1463 /* Repeat as long as we have more pattern to process and more output
1466 if (*pat_ptr
!= '%') {
1467 if (out_ptr
== out_end
)
1469 *out_ptr
++ = *pat_ptr
++;
1471 switch (*++pat_ptr
) {
1474 /* Double percent, output one percent */
1476 if (out_ptr
== out_end
)
1483 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1484 "%d", task_tgid_vnr(current
));
1485 if (rc
> out_end
- out_ptr
)
1491 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1493 if (rc
> out_end
- out_ptr
)
1499 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1501 if (rc
> out_end
- out_ptr
)
1505 /* signal that caused the coredump */
1507 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1509 if (rc
> out_end
- out_ptr
)
1513 /* UNIX time of coredump */
1516 do_gettimeofday(&tv
);
1517 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1519 if (rc
> out_end
- out_ptr
)
1526 down_read(&uts_sem
);
1527 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1528 "%s", utsname()->nodename
);
1530 if (rc
> out_end
- out_ptr
)
1536 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1537 "%s", current
->comm
);
1538 if (rc
> out_end
- out_ptr
)
1542 /* core limit size */
1544 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1545 "%lu", current
->signal
->rlim
[RLIMIT_CORE
].rlim_cur
);
1546 if (rc
> out_end
- out_ptr
)
1556 /* Backward compatibility with core_uses_pid:
1558 * If core_pattern does not include a %p (as is the default)
1559 * and core_uses_pid is set, then .%pid will be appended to
1560 * the filename. Do not do this for piped commands. */
1561 if (!ispipe
&& !pid_in_pattern
&& core_uses_pid
) {
1562 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1563 ".%d", task_tgid_vnr(current
));
1564 if (rc
> out_end
- out_ptr
)
1573 static int zap_process(struct task_struct
*start
)
1575 struct task_struct
*t
;
1578 start
->signal
->flags
= SIGNAL_GROUP_EXIT
;
1579 start
->signal
->group_stop_count
= 0;
1583 if (t
!= current
&& t
->mm
) {
1584 sigaddset(&t
->pending
.signal
, SIGKILL
);
1585 signal_wake_up(t
, 1);
1588 } while_each_thread(start
, t
);
1593 static inline int zap_threads(struct task_struct
*tsk
, struct mm_struct
*mm
,
1594 struct core_state
*core_state
, int exit_code
)
1596 struct task_struct
*g
, *p
;
1597 unsigned long flags
;
1600 spin_lock_irq(&tsk
->sighand
->siglock
);
1601 if (!signal_group_exit(tsk
->signal
)) {
1602 mm
->core_state
= core_state
;
1603 tsk
->signal
->group_exit_code
= exit_code
;
1604 nr
= zap_process(tsk
);
1606 spin_unlock_irq(&tsk
->sighand
->siglock
);
1607 if (unlikely(nr
< 0))
1610 if (atomic_read(&mm
->mm_users
) == nr
+ 1)
1613 * We should find and kill all tasks which use this mm, and we should
1614 * count them correctly into ->nr_threads. We don't take tasklist
1615 * lock, but this is safe wrt:
1618 * None of sub-threads can fork after zap_process(leader). All
1619 * processes which were created before this point should be
1620 * visible to zap_threads() because copy_process() adds the new
1621 * process to the tail of init_task.tasks list, and lock/unlock
1622 * of ->siglock provides a memory barrier.
1625 * The caller holds mm->mmap_sem. This means that the task which
1626 * uses this mm can't pass exit_mm(), so it can't exit or clear
1630 * It does list_replace_rcu(&leader->tasks, ¤t->tasks),
1631 * we must see either old or new leader, this does not matter.
1632 * However, it can change p->sighand, so lock_task_sighand(p)
1633 * must be used. Since p->mm != NULL and we hold ->mmap_sem
1636 * Note also that "g" can be the old leader with ->mm == NULL
1637 * and already unhashed and thus removed from ->thread_group.
1638 * This is OK, __unhash_process()->list_del_rcu() does not
1639 * clear the ->next pointer, we will find the new leader via
1643 for_each_process(g
) {
1644 if (g
== tsk
->group_leader
)
1646 if (g
->flags
& PF_KTHREAD
)
1651 if (unlikely(p
->mm
== mm
)) {
1652 lock_task_sighand(p
, &flags
);
1653 nr
+= zap_process(p
);
1654 unlock_task_sighand(p
, &flags
);
1658 } while_each_thread(g
, p
);
1662 atomic_set(&core_state
->nr_threads
, nr
);
1666 static int coredump_wait(int exit_code
, struct core_state
*core_state
)
1668 struct task_struct
*tsk
= current
;
1669 struct mm_struct
*mm
= tsk
->mm
;
1670 struct completion
*vfork_done
;
1673 init_completion(&core_state
->startup
);
1674 core_state
->dumper
.task
= tsk
;
1675 core_state
->dumper
.next
= NULL
;
1676 core_waiters
= zap_threads(tsk
, mm
, core_state
, exit_code
);
1677 up_write(&mm
->mmap_sem
);
1679 if (unlikely(core_waiters
< 0))
1683 * Make sure nobody is waiting for us to release the VM,
1684 * otherwise we can deadlock when we wait on each other
1686 vfork_done
= tsk
->vfork_done
;
1688 tsk
->vfork_done
= NULL
;
1689 complete(vfork_done
);
1693 wait_for_completion(&core_state
->startup
);
1695 return core_waiters
;
1698 static void coredump_finish(struct mm_struct
*mm
)
1700 struct core_thread
*curr
, *next
;
1701 struct task_struct
*task
;
1703 next
= mm
->core_state
->dumper
.next
;
1704 while ((curr
= next
) != NULL
) {
1708 * see exit_mm(), curr->task must not see
1709 * ->task == NULL before we read ->next.
1713 wake_up_process(task
);
1716 mm
->core_state
= NULL
;
1720 * set_dumpable converts traditional three-value dumpable to two flags and
1721 * stores them into mm->flags. It modifies lower two bits of mm->flags, but
1722 * these bits are not changed atomically. So get_dumpable can observe the
1723 * intermediate state. To avoid doing unexpected behavior, get get_dumpable
1724 * return either old dumpable or new one by paying attention to the order of
1725 * modifying the bits.
1727 * dumpable | mm->flags (binary)
1728 * old new | initial interim final
1729 * ---------+-----------------------
1737 * (*) get_dumpable regards interim value of 10 as 11.
1739 void set_dumpable(struct mm_struct
*mm
, int value
)
1743 clear_bit(MMF_DUMPABLE
, &mm
->flags
);
1745 clear_bit(MMF_DUMP_SECURELY
, &mm
->flags
);
1748 set_bit(MMF_DUMPABLE
, &mm
->flags
);
1750 clear_bit(MMF_DUMP_SECURELY
, &mm
->flags
);
1753 set_bit(MMF_DUMP_SECURELY
, &mm
->flags
);
1755 set_bit(MMF_DUMPABLE
, &mm
->flags
);
1760 int get_dumpable(struct mm_struct
*mm
)
1764 ret
= mm
->flags
& 0x3;
1765 return (ret
>= 2) ? 2 : ret
;
1768 static void wait_for_dump_helpers(struct file
*file
)
1770 struct pipe_inode_info
*pipe
;
1772 pipe
= file
->f_path
.dentry
->d_inode
->i_pipe
;
1778 while ((pipe
->readers
> 1) && (!signal_pending(current
))) {
1779 wake_up_interruptible_sync(&pipe
->wait
);
1780 kill_fasync(&pipe
->fasync_readers
, SIGIO
, POLL_IN
);
1791 void do_coredump(long signr
, int exit_code
, struct pt_regs
*regs
)
1793 struct core_state core_state
;
1794 char corename
[CORENAME_MAX_SIZE
+ 1];
1795 struct mm_struct
*mm
= current
->mm
;
1796 struct linux_binfmt
* binfmt
;
1797 struct inode
* inode
;
1799 const struct cred
*old_cred
;
1804 unsigned long core_limit
= current
->signal
->rlim
[RLIMIT_CORE
].rlim_cur
;
1805 char **helper_argv
= NULL
;
1806 int helper_argc
= 0;
1808 static atomic_t core_dump_count
= ATOMIC_INIT(0);
1810 audit_core_dumps(signr
);
1812 binfmt
= mm
->binfmt
;
1813 if (!binfmt
|| !binfmt
->core_dump
)
1816 cred
= prepare_creds();
1822 down_write(&mm
->mmap_sem
);
1824 * If another thread got here first, or we are not dumpable, bail out.
1826 if (mm
->core_state
|| !get_dumpable(mm
)) {
1827 up_write(&mm
->mmap_sem
);
1833 * We cannot trust fsuid as being the "true" uid of the
1834 * process nor do we know its entire history. We only know it
1835 * was tainted so we dump it as root in mode 2.
1837 if (get_dumpable(mm
) == 2) { /* Setuid core dump mode */
1838 flag
= O_EXCL
; /* Stop rewrite attacks */
1839 cred
->fsuid
= 0; /* Dump root private */
1842 retval
= coredump_wait(exit_code
, &core_state
);
1848 old_cred
= override_creds(cred
);
1851 * Clear any false indication of pending signals that might
1852 * be seen by the filesystem code called to write the core file.
1854 clear_thread_flag(TIF_SIGPENDING
);
1857 * lock_kernel() because format_corename() is controlled by sysctl, which
1858 * uses lock_kernel()
1861 ispipe
= format_corename(corename
, signr
);
1864 if ((!ispipe
) && (core_limit
< binfmt
->min_coredump
))
1868 if (core_limit
== 0) {
1870 * Normally core limits are irrelevant to pipes, since
1871 * we're not writing to the file system, but we use
1872 * core_limit of 0 here as a speacial value. Any
1873 * non-zero limit gets set to RLIM_INFINITY below, but
1874 * a limit of 0 skips the dump. This is a consistent
1875 * way to catch recursive crashes. We can still crash
1876 * if the core_pattern binary sets RLIM_CORE = !0
1877 * but it runs as root, and can do lots of stupid things
1878 * Note that we use task_tgid_vnr here to grab the pid
1879 * of the process group leader. That way we get the
1880 * right pid if a thread in a multi-threaded
1881 * core_pattern process dies.
1884 "Process %d(%s) has RLIMIT_CORE set to 0\n",
1885 task_tgid_vnr(current
), current
->comm
);
1886 printk(KERN_WARNING
"Aborting core\n");
1890 dump_count
= atomic_inc_return(&core_dump_count
);
1891 if (core_pipe_limit
&& (core_pipe_limit
< dump_count
)) {
1892 printk(KERN_WARNING
"Pid %d(%s) over core_pipe_limit\n",
1893 task_tgid_vnr(current
), current
->comm
);
1894 printk(KERN_WARNING
"Skipping core dump\n");
1895 goto fail_dropcount
;
1898 helper_argv
= argv_split(GFP_KERNEL
, corename
+1, &helper_argc
);
1900 printk(KERN_WARNING
"%s failed to allocate memory\n",
1902 goto fail_dropcount
;
1905 core_limit
= RLIM_INFINITY
;
1907 /* SIGPIPE can happen, but it's just never processed */
1908 if (call_usermodehelper_pipe(helper_argv
[0], helper_argv
, NULL
,
1910 printk(KERN_INFO
"Core dump to %s pipe failed\n",
1912 goto fail_dropcount
;
1915 file
= filp_open(corename
,
1916 O_CREAT
| 2 | O_NOFOLLOW
| O_LARGEFILE
| flag
,
1919 goto fail_dropcount
;
1920 inode
= file
->f_path
.dentry
->d_inode
;
1921 if (inode
->i_nlink
> 1)
1922 goto close_fail
; /* multiple links - don't dump */
1923 if (!ispipe
&& d_unhashed(file
->f_path
.dentry
))
1926 /* AK: actually i see no reason to not allow this for named pipes etc.,
1927 but keep the previous behaviour for now. */
1928 if (!ispipe
&& !S_ISREG(inode
->i_mode
))
1931 * Dont allow local users get cute and trick others to coredump
1932 * into their pre-created files:
1933 * Note, this is not relevant for pipes
1935 if (!ispipe
&& (inode
->i_uid
!= current_fsuid()))
1939 if (!file
->f_op
->write
)
1941 if (!ispipe
&& do_truncate(file
->f_path
.dentry
, 0, 0, file
) != 0)
1944 retval
= binfmt
->core_dump(signr
, regs
, file
, core_limit
);
1947 current
->signal
->group_exit_code
|= 0x80;
1949 if (ispipe
&& core_pipe_limit
)
1950 wait_for_dump_helpers(file
);
1951 filp_close(file
, NULL
);
1954 atomic_dec(&core_dump_count
);
1957 argv_free(helper_argv
);
1959 revert_creds(old_cred
);
1961 coredump_finish(mm
);