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/config.h>
26 #include <linux/slab.h>
27 #include <linux/file.h>
28 #include <linux/mman.h>
29 #include <linux/a.out.h>
30 #include <linux/stat.h>
31 #include <linux/fcntl.h>
32 #include <linux/smp_lock.h>
33 #include <linux/init.h>
34 #include <linux/pagemap.h>
35 #include <linux/highmem.h>
36 #include <linux/spinlock.h>
37 #include <linux/personality.h>
38 #include <linux/binfmts.h>
39 #include <linux/swap.h>
40 #include <linux/utsname.h>
41 #include <linux/module.h>
42 #include <linux/namei.h>
43 #include <linux/proc_fs.h>
44 #include <linux/ptrace.h>
45 #include <linux/mount.h>
46 #include <linux/security.h>
47 #include <linux/rmap-locking.h>
49 #include <asm/uaccess.h>
50 #include <asm/pgalloc.h>
51 #include <asm/mmu_context.h>
54 #include <linux/kmod.h>
58 char core_pattern
[65] = "core";
59 /* The maximal length of core_pattern is also specified in sysctl.c */
61 static struct linux_binfmt
*formats
;
62 static rwlock_t binfmt_lock
= RW_LOCK_UNLOCKED
;
64 int register_binfmt(struct linux_binfmt
* fmt
)
66 struct linux_binfmt
** tmp
= &formats
;
72 write_lock(&binfmt_lock
);
75 write_unlock(&binfmt_lock
);
82 write_unlock(&binfmt_lock
);
86 int unregister_binfmt(struct linux_binfmt
* fmt
)
88 struct linux_binfmt
** tmp
= &formats
;
90 write_lock(&binfmt_lock
);
94 write_unlock(&binfmt_lock
);
99 write_unlock(&binfmt_lock
);
103 static inline void put_binfmt(struct linux_binfmt
* fmt
)
105 module_put(fmt
->module
);
109 * Note that a shared library must be both readable and executable due to
112 * Also note that we take the address to load from from the file itself.
114 asmlinkage
long sys_uselib(const char __user
* library
)
120 error
= user_path_walk(library
, &nd
);
125 if (!S_ISREG(nd
.dentry
->d_inode
->i_mode
))
128 error
= permission(nd
.dentry
->d_inode
, MAY_READ
| MAY_EXEC
);
132 file
= dentry_open(nd
.dentry
, nd
.mnt
, O_RDONLY
);
133 error
= PTR_ERR(file
);
139 struct linux_binfmt
* fmt
;
141 read_lock(&binfmt_lock
);
142 for (fmt
= formats
; fmt
; fmt
= fmt
->next
) {
143 if (!fmt
->load_shlib
)
145 if (!try_module_get(fmt
->module
))
147 read_unlock(&binfmt_lock
);
148 error
= fmt
->load_shlib(file
);
149 read_lock(&binfmt_lock
);
151 if (error
!= -ENOEXEC
)
154 read_unlock(&binfmt_lock
);
165 * count() counts the number of strings in array ARGV.
167 static int count(char __user
* __user
* argv
, int max
)
175 if (get_user(p
, argv
))
188 * 'copy_strings()' copies argument/environment strings from user
189 * memory to free pages in kernel mem. These are in a format ready
190 * to be put directly into the top of new user memory.
192 int copy_strings(int argc
,char __user
* __user
* argv
, struct linux_binprm
*bprm
)
194 struct page
*kmapped_page
= NULL
;
203 if (get_user(str
, argv
+argc
) ||
204 !(len
= strnlen_user(str
, bprm
->p
))) {
215 /* XXX: add architecture specific overflow check here. */
220 int offset
, bytes_to_copy
;
223 offset
= pos
% PAGE_SIZE
;
225 page
= bprm
->page
[i
];
228 page
= alloc_page(GFP_HIGHUSER
);
229 bprm
->page
[i
] = page
;
237 if (page
!= kmapped_page
) {
239 kunmap(kmapped_page
);
241 kaddr
= kmap(kmapped_page
);
244 memset(kaddr
, 0, offset
);
245 bytes_to_copy
= PAGE_SIZE
- offset
;
246 if (bytes_to_copy
> len
) {
249 memset(kaddr
+offset
+len
, 0,
250 PAGE_SIZE
-offset
-len
);
252 err
= copy_from_user(kaddr
+offset
, str
, bytes_to_copy
);
258 pos
+= bytes_to_copy
;
259 str
+= bytes_to_copy
;
260 len
-= bytes_to_copy
;
266 kunmap(kmapped_page
);
271 * Like copy_strings, but get argv and its values from kernel memory.
273 int copy_strings_kernel(int argc
,char ** argv
, struct linux_binprm
*bprm
)
276 mm_segment_t oldfs
= get_fs();
278 r
= copy_strings(argc
, (char __user
* __user
*)argv
, bprm
);
285 * This routine is used to map in a page into an address space: needed by
286 * execve() for the initial stack and environment pages.
288 * tsk->mmap_sem is held for writing.
290 void put_dirty_page(struct task_struct
*tsk
, struct page
*page
,
291 unsigned long address
, pgprot_t prot
)
296 struct pte_chain
*pte_chain
;
298 if (page_count(page
) != 1)
299 printk(KERN_ERR
"mem_map disagrees with %p at %08lx\n",
302 pgd
= pgd_offset(tsk
->mm
, address
);
303 pte_chain
= pte_chain_alloc(GFP_KERNEL
);
306 spin_lock(&tsk
->mm
->page_table_lock
);
307 pmd
= pmd_alloc(tsk
->mm
, pgd
, address
);
310 pte
= pte_alloc_map(tsk
->mm
, pmd
, address
);
313 if (!pte_none(*pte
)) {
317 lru_cache_add_active(page
);
318 flush_dcache_page(page
);
319 set_pte(pte
, pte_mkdirty(pte_mkwrite(mk_pte(page
, prot
))));
320 pte_chain
= page_add_rmap(page
, pte
, pte_chain
);
323 spin_unlock(&tsk
->mm
->page_table_lock
);
325 /* no need for flush_tlb */
326 pte_chain_free(pte_chain
);
329 spin_unlock(&tsk
->mm
->page_table_lock
);
332 force_sig(SIGKILL
, tsk
);
333 pte_chain_free(pte_chain
);
337 int setup_arg_pages(struct linux_binprm
*bprm
)
339 unsigned long stack_base
;
340 struct vm_area_struct
*mpnt
;
341 struct mm_struct
*mm
= current
->mm
;
344 #ifdef CONFIG_STACK_GROWSUP
345 /* Move the argument and environment strings to the bottom of the
351 /* Start by shifting all the pages down */
353 for (j
= 0; j
< MAX_ARG_PAGES
; j
++) {
354 struct page
*page
= bprm
->page
[j
];
357 bprm
->page
[i
++] = page
;
360 /* Now move them within their pages */
361 offset
= bprm
->p
% PAGE_SIZE
;
362 to
= kmap(bprm
->page
[0]);
363 for (j
= 1; j
< i
; j
++) {
364 memmove(to
, to
+ offset
, PAGE_SIZE
- offset
);
365 from
= kmap(bprm
->page
[j
]);
366 memcpy(to
+ PAGE_SIZE
- offset
, from
, offset
);
367 kunmap(bprm
->page
[j
- 1]);
370 memmove(to
, to
+ offset
, PAGE_SIZE
- offset
);
371 kunmap(bprm
->page
[j
- 1]);
373 /* Adjust bprm->p to point to the end of the strings. */
374 bprm
->p
= PAGE_SIZE
* i
- offset
;
375 stack_base
= STACK_TOP
- current
->rlim
[RLIMIT_STACK
].rlim_max
;
376 mm
->arg_start
= stack_base
;
378 /* zero pages that were copied above */
379 while (i
< MAX_ARG_PAGES
)
380 bprm
->page
[i
++] = NULL
;
382 stack_base
= STACK_TOP
- MAX_ARG_PAGES
* PAGE_SIZE
;
383 mm
->arg_start
= bprm
->p
+ stack_base
;
386 bprm
->p
+= stack_base
;
388 bprm
->loader
+= stack_base
;
389 bprm
->exec
+= stack_base
;
391 mpnt
= kmem_cache_alloc(vm_area_cachep
, SLAB_KERNEL
);
395 if (!vm_enough_memory((STACK_TOP
- (PAGE_MASK
& (unsigned long) bprm
->p
))>>PAGE_SHIFT
)) {
396 kmem_cache_free(vm_area_cachep
, mpnt
);
400 down_write(&mm
->mmap_sem
);
403 #ifdef CONFIG_STACK_GROWSUP
404 mpnt
->vm_start
= stack_base
;
405 mpnt
->vm_end
= PAGE_MASK
&
406 (PAGE_SIZE
- 1 + (unsigned long) bprm
->p
);
408 mpnt
->vm_start
= PAGE_MASK
& (unsigned long) bprm
->p
;
409 mpnt
->vm_end
= STACK_TOP
;
411 mpnt
->vm_page_prot
= protection_map
[VM_STACK_FLAGS
& 0x7];
412 mpnt
->vm_flags
= VM_STACK_FLAGS
;
415 mpnt
->vm_file
= NULL
;
416 INIT_LIST_HEAD(&mpnt
->shared
);
417 mpnt
->vm_private_data
= (void *) 0;
418 insert_vm_struct(mm
, mpnt
);
419 mm
->total_vm
= (mpnt
->vm_end
- mpnt
->vm_start
) >> PAGE_SHIFT
;
422 for (i
= 0 ; i
< MAX_ARG_PAGES
; i
++) {
423 struct page
*page
= bprm
->page
[i
];
425 bprm
->page
[i
] = NULL
;
426 put_dirty_page(current
, page
, stack_base
,
429 stack_base
+= PAGE_SIZE
;
431 up_write(&mm
->mmap_sem
);
436 #define free_arg_pages(bprm) do { } while (0)
440 static inline void free_arg_pages(struct linux_binprm
*bprm
)
444 for (i
= 0 ; i
< MAX_ARG_PAGES
; i
++) {
446 __free_page(bprm
->page
[i
]);
447 bprm
->page
[i
] = NULL
;
451 #endif /* CONFIG_MMU */
453 struct file
*open_exec(const char *name
)
456 int err
= path_lookup(name
, LOOKUP_FOLLOW
, &nd
);
457 struct file
*file
= ERR_PTR(err
);
460 struct inode
*inode
= nd
.dentry
->d_inode
;
461 file
= ERR_PTR(-EACCES
);
462 if (!(nd
.mnt
->mnt_flags
& MNT_NOEXEC
) &&
463 S_ISREG(inode
->i_mode
)) {
464 int err
= permission(inode
, MAY_EXEC
);
465 if (!err
&& !(inode
->i_mode
& 0111))
469 file
= dentry_open(nd
.dentry
, nd
.mnt
, O_RDONLY
);
471 err
= deny_write_access(file
);
486 int kernel_read(struct file
*file
, unsigned long offset
,
487 char *addr
, unsigned long count
)
495 /* The cast to a user pointer is valid due to the set_fs() */
496 result
= vfs_read(file
, (void __user
*)addr
, count
, &pos
);
501 static int exec_mmap(struct mm_struct
*mm
)
503 struct task_struct
*tsk
;
504 struct mm_struct
* old_mm
, *active_mm
;
506 /* Add it to the list of mm's */
507 spin_lock(&mmlist_lock
);
508 list_add(&mm
->mmlist
, &init_mm
.mmlist
);
510 spin_unlock(&mmlist_lock
);
512 /* Notify parent that we're no longer interested in the old VM */
514 old_mm
= current
->mm
;
515 mm_release(tsk
, old_mm
);
518 active_mm
= tsk
->active_mm
;
521 activate_mm(active_mm
, mm
);
524 if (active_mm
!= old_mm
) BUG();
533 * This function makes sure the current process has its own signal table,
534 * so that flush_signal_handlers can later reset the handlers without
535 * disturbing other processes. (Other processes might share the signal
536 * table via the CLONE_SIGHAND option to clone().)
538 static inline int de_thread(struct task_struct
*tsk
)
540 struct signal_struct
*newsig
, *oldsig
= tsk
->signal
;
541 struct sighand_struct
*newsighand
, *oldsighand
= tsk
->sighand
;
542 spinlock_t
*lock
= &oldsighand
->siglock
;
546 * If we don't share sighandlers, then we aren't sharing anything
547 * and we can just re-use it all.
549 if (atomic_read(&oldsighand
->count
) <= 1)
552 newsighand
= kmem_cache_alloc(sighand_cachep
, GFP_KERNEL
);
556 spin_lock_init(&newsighand
->siglock
);
557 atomic_set(&newsighand
->count
, 1);
558 memcpy(newsighand
->action
, oldsighand
->action
, sizeof(newsighand
->action
));
561 * See if we need to allocate a new signal structure
564 if (atomic_read(&oldsig
->count
) > 1) {
565 newsig
= kmem_cache_alloc(signal_cachep
, GFP_KERNEL
);
567 kmem_cache_free(sighand_cachep
, newsighand
);
570 atomic_set(&newsig
->count
, 1);
571 newsig
->group_exit
= 0;
572 newsig
->group_exit_code
= 0;
573 newsig
->group_exit_task
= NULL
;
574 newsig
->group_stop_count
= 0;
575 newsig
->curr_target
= NULL
;
576 init_sigpending(&newsig
->shared_pending
);
579 if (thread_group_empty(current
))
580 goto no_thread_group
;
583 * Kill all other threads in the thread group.
584 * We must hold tasklist_lock to call zap_other_threads.
586 read_lock(&tasklist_lock
);
588 if (oldsig
->group_exit
) {
590 * Another group action in progress, just
591 * return so that the signal is processed.
593 spin_unlock_irq(lock
);
594 read_unlock(&tasklist_lock
);
595 kmem_cache_free(sighand_cachep
, newsighand
);
597 kmem_cache_free(signal_cachep
, newsig
);
600 oldsig
->group_exit
= 1;
601 zap_other_threads(current
);
602 read_unlock(&tasklist_lock
);
605 * Account for the thread group leader hanging around:
608 if (current
->pid
== current
->tgid
)
610 while (atomic_read(&oldsig
->count
) > count
) {
611 oldsig
->group_exit_task
= current
;
612 oldsig
->notify_count
= count
;
613 __set_current_state(TASK_UNINTERRUPTIBLE
);
614 spin_unlock_irq(lock
);
617 if (oldsig
->group_exit_task
)
620 spin_unlock_irq(lock
);
623 * At this point all other threads have exited, all we have to
624 * do is to wait for the thread group leader to become inactive,
625 * and to assume its PID:
627 if (current
->pid
!= current
->tgid
) {
628 struct task_struct
*leader
= current
->group_leader
, *parent
;
629 struct dentry
*proc_dentry1
, *proc_dentry2
;
630 unsigned long state
, ptrace
;
633 * Wait for the thread group leader to be a zombie.
634 * It should already be zombie at this point, most
637 while (leader
->state
!= TASK_ZOMBIE
)
640 spin_lock(&leader
->proc_lock
);
641 spin_lock(¤t
->proc_lock
);
642 proc_dentry1
= proc_pid_unhash(current
);
643 proc_dentry2
= proc_pid_unhash(leader
);
644 write_lock_irq(&tasklist_lock
);
646 if (leader
->tgid
!= current
->tgid
)
648 if (current
->pid
== current
->tgid
)
651 * An exec() starts a new thread group with the
652 * TGID of the previous thread group. Rehash the
653 * two threads with a switched PID, and release
654 * the former thread group leader:
656 ptrace
= leader
->ptrace
;
657 parent
= leader
->parent
;
659 ptrace_unlink(current
);
660 ptrace_unlink(leader
);
661 remove_parent(current
);
662 remove_parent(leader
);
664 switch_exec_pids(leader
, current
);
666 current
->parent
= current
->real_parent
= leader
->real_parent
;
667 leader
->parent
= leader
->real_parent
= child_reaper
;
668 current
->group_leader
= current
;
669 leader
->group_leader
= leader
;
671 add_parent(current
, current
->parent
);
672 add_parent(leader
, leader
->parent
);
674 current
->ptrace
= ptrace
;
675 __ptrace_link(current
, parent
);
678 list_del(¤t
->tasks
);
679 list_add_tail(¤t
->tasks
, &init_task
.tasks
);
680 current
->exit_signal
= SIGCHLD
;
681 state
= leader
->state
;
683 write_unlock_irq(&tasklist_lock
);
684 spin_unlock(&leader
->proc_lock
);
685 spin_unlock(¤t
->proc_lock
);
686 proc_pid_flush(proc_dentry1
);
687 proc_pid_flush(proc_dentry2
);
689 if (state
!= TASK_ZOMBIE
)
691 release_task(leader
);
696 write_lock_irq(&tasklist_lock
);
697 spin_lock(&oldsighand
->siglock
);
698 spin_lock(&newsighand
->siglock
);
700 if (current
== oldsig
->curr_target
)
701 oldsig
->curr_target
= next_thread(current
);
703 current
->signal
= newsig
;
704 current
->sighand
= newsighand
;
705 init_sigpending(¤t
->pending
);
708 spin_unlock(&newsighand
->siglock
);
709 spin_unlock(&oldsighand
->siglock
);
710 write_unlock_irq(&tasklist_lock
);
712 if (newsig
&& atomic_dec_and_test(&oldsig
->count
))
713 kmem_cache_free(signal_cachep
, oldsig
);
715 if (atomic_dec_and_test(&oldsighand
->count
))
716 kmem_cache_free(sighand_cachep
, oldsighand
);
718 if (!thread_group_empty(current
))
720 if (current
->tgid
!= current
->pid
)
726 * These functions flushes out all traces of the currently running executable
727 * so that a new one can be started
730 static inline void flush_old_files(struct files_struct
* files
)
734 spin_lock(&files
->file_lock
);
736 unsigned long set
, i
;
740 if (i
>= files
->max_fds
|| i
>= files
->max_fdset
)
742 set
= files
->close_on_exec
->fds_bits
[j
];
745 files
->close_on_exec
->fds_bits
[j
] = 0;
746 spin_unlock(&files
->file_lock
);
747 for ( ; set
; i
++,set
>>= 1) {
752 spin_lock(&files
->file_lock
);
755 spin_unlock(&files
->file_lock
);
758 int flush_old_exec(struct linux_binprm
* bprm
)
764 * Release all of the old mmap stuff
766 retval
= exec_mmap(bprm
->mm
);
770 * Make sure we have a private signal table and that
771 * we are unassociated from the previous thread group.
773 retval
= de_thread(current
);
777 /* This is the point of no return */
779 current
->sas_ss_sp
= current
->sas_ss_size
= 0;
781 if (current
->euid
== current
->uid
&& current
->egid
== current
->gid
)
782 current
->mm
->dumpable
= 1;
783 name
= bprm
->filename
;
784 for (i
=0; (ch
= *(name
++)) != '\0';) {
789 current
->comm
[i
++] = ch
;
791 current
->comm
[i
] = '\0';
795 if (bprm
->e_uid
!= current
->euid
|| bprm
->e_gid
!= current
->egid
||
796 permission(bprm
->file
->f_dentry
->d_inode
,MAY_READ
))
797 current
->mm
->dumpable
= 0;
799 /* An exec changes our domain. We are no longer part of the thread
802 current
->self_exec_id
++;
804 flush_signal_handlers(current
, 0);
805 flush_old_files(current
->files
);
806 exit_itimers(current
);
815 * We mustn't allow tracing of suid binaries, unless
816 * the tracer has the capability to trace anything..
818 static inline int must_not_trace_exec(struct task_struct
* p
)
820 return (p
->ptrace
& PT_PTRACED
) && !(p
->ptrace
& PT_PTRACE_CAP
);
824 * Fill the binprm structure from the inode.
825 * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes
827 int prepare_binprm(struct linux_binprm
*bprm
)
830 struct inode
* inode
= bprm
->file
->f_dentry
->d_inode
;
833 mode
= inode
->i_mode
;
835 * Check execute perms again - if the caller has CAP_DAC_OVERRIDE,
836 * vfs_permission lets a non-executable through
838 if (!(mode
& 0111)) /* with at least _one_ execute bit set */
840 if (bprm
->file
->f_op
== NULL
)
843 bprm
->e_uid
= current
->euid
;
844 bprm
->e_gid
= current
->egid
;
846 if(!(bprm
->file
->f_vfsmnt
->mnt_flags
& MNT_NOSUID
)) {
849 bprm
->e_uid
= inode
->i_uid
;
853 * If setgid is set but no group execute bit then this
854 * is a candidate for mandatory locking, not a setgid
857 if ((mode
& (S_ISGID
| S_IXGRP
)) == (S_ISGID
| S_IXGRP
))
858 bprm
->e_gid
= inode
->i_gid
;
861 /* fill in binprm security blob */
862 retval
= security_bprm_set(bprm
);
866 memset(bprm
->buf
,0,BINPRM_BUF_SIZE
);
867 return kernel_read(bprm
->file
,0,bprm
->buf
,BINPRM_BUF_SIZE
);
871 * This function is used to produce the new IDs and capabilities
872 * from the old ones and the file's capabilities.
874 * The formula used for evolving capabilities is:
877 * (***) pP' = (fP & X) | (fI & pI)
878 * pE' = pP' & fE [NB. fE is 0 or ~0]
880 * I=Inheritable, P=Permitted, E=Effective // p=process, f=file
881 * ' indicates post-exec(), and X is the global 'cap_bset'.
885 void compute_creds(struct linux_binprm
*bprm
)
888 if (bprm
->e_uid
!= current
->uid
|| bprm
->e_gid
!= current
->gid
) {
889 current
->mm
->dumpable
= 0;
891 if (must_not_trace_exec(current
)
892 || atomic_read(¤t
->fs
->count
) > 1
893 || atomic_read(¤t
->files
->count
) > 1
894 || atomic_read(¤t
->sighand
->count
) > 1) {
895 if(!capable(CAP_SETUID
)) {
896 bprm
->e_uid
= current
->uid
;
897 bprm
->e_gid
= current
->gid
;
902 current
->suid
= current
->euid
= current
->fsuid
= bprm
->e_uid
;
903 current
->sgid
= current
->egid
= current
->fsgid
= bprm
->e_gid
;
905 task_unlock(current
);
907 security_bprm_compute_creds(bprm
);
910 void remove_arg_zero(struct linux_binprm
*bprm
)
913 unsigned long offset
;
917 offset
= bprm
->p
% PAGE_SIZE
;
920 while (bprm
->p
++, *(kaddr
+offset
++)) {
921 if (offset
!= PAGE_SIZE
)
926 page
= bprm
->page
[bprm
->p
/PAGE_SIZE
];
935 * cycle the list of binary formats handler, until one recognizes the image
937 int search_binary_handler(struct linux_binprm
*bprm
,struct pt_regs
*regs
)
940 struct linux_binfmt
*fmt
;
942 /* handle /sbin/loader.. */
944 struct exec
* eh
= (struct exec
*) bprm
->buf
;
946 if (!bprm
->loader
&& eh
->fh
.f_magic
== 0x183 &&
947 (eh
->fh
.f_flags
& 0x3000) == 0x3000)
950 unsigned long loader
;
952 allow_write_access(bprm
->file
);
956 loader
= PAGE_SIZE
*MAX_ARG_PAGES
-sizeof(void *);
958 file
= open_exec("/sbin/loader");
959 retval
= PTR_ERR(file
);
963 /* Remember if the application is TASO. */
964 bprm
->sh_bang
= eh
->ah
.entry
< 0x100000000;
967 bprm
->loader
= loader
;
968 retval
= prepare_binprm(bprm
);
971 /* should call search_binary_handler recursively here,
972 but it does not matter */
976 retval
= security_bprm_check(bprm
);
980 /* kernel module loader fixup */
981 /* so we don't try to load run modprobe in kernel space. */
983 for (try=0; try<2; try++) {
984 read_lock(&binfmt_lock
);
985 for (fmt
= formats
; fmt
; fmt
= fmt
->next
) {
986 int (*fn
)(struct linux_binprm
*, struct pt_regs
*) = fmt
->load_binary
;
989 if (!try_module_get(fmt
->module
))
991 read_unlock(&binfmt_lock
);
992 retval
= fn(bprm
, regs
);
995 allow_write_access(bprm
->file
);
999 current
->did_exec
= 1;
1002 read_lock(&binfmt_lock
);
1004 if (retval
!= -ENOEXEC
)
1007 read_unlock(&binfmt_lock
);
1011 read_unlock(&binfmt_lock
);
1012 if (retval
!= -ENOEXEC
) {
1016 #define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e))
1017 if (printable(bprm
->buf
[0]) &&
1018 printable(bprm
->buf
[1]) &&
1019 printable(bprm
->buf
[2]) &&
1020 printable(bprm
->buf
[3]))
1021 break; /* -ENOEXEC */
1022 request_module("binfmt-%04x", *(unsigned short *)(&bprm
->buf
[2]));
1030 * sys_execve() executes a new program.
1032 int do_execve(char * filename
,
1033 char __user
*__user
*argv
,
1034 char __user
*__user
*envp
,
1035 struct pt_regs
* regs
)
1037 struct linux_binprm bprm
;
1042 sched_balance_exec();
1044 file
= open_exec(filename
);
1046 retval
= PTR_ERR(file
);
1050 bprm
.p
= PAGE_SIZE
*MAX_ARG_PAGES
-sizeof(void *);
1051 memset(bprm
.page
, 0, MAX_ARG_PAGES
*sizeof(bprm
.page
[0]));
1054 bprm
.filename
= filename
;
1058 bprm
.security
= NULL
;
1059 bprm
.mm
= mm_alloc();
1064 retval
= init_new_context(current
, bprm
.mm
);
1068 bprm
.argc
= count(argv
, bprm
.p
/ sizeof(void *));
1069 if ((retval
= bprm
.argc
) < 0)
1072 bprm
.envc
= count(envp
, bprm
.p
/ sizeof(void *));
1073 if ((retval
= bprm
.envc
) < 0)
1076 retval
= security_bprm_alloc(&bprm
);
1080 retval
= prepare_binprm(&bprm
);
1084 retval
= copy_strings_kernel(1, &bprm
.filename
, &bprm
);
1089 retval
= copy_strings(bprm
.envc
, envp
, &bprm
);
1093 retval
= copy_strings(bprm
.argc
, argv
, &bprm
);
1097 retval
= search_binary_handler(&bprm
,regs
);
1099 free_arg_pages(&bprm
);
1101 /* execve success */
1102 security_bprm_free(&bprm
);
1107 /* Something went wrong, return the inode and free the argument pages*/
1108 for (i
= 0 ; i
< MAX_ARG_PAGES
; i
++) {
1109 struct page
* page
= bprm
.page
[i
];
1115 security_bprm_free(&bprm
);
1122 allow_write_access(bprm
.file
);
1128 int set_binfmt(struct linux_binfmt
*new)
1130 struct linux_binfmt
*old
= current
->binfmt
;
1133 if (!try_module_get(new->module
))
1136 current
->binfmt
= new;
1138 module_put(old
->module
);
1142 #define CORENAME_MAX_SIZE 64
1144 /* format_corename will inspect the pattern parameter, and output a
1145 * name into corename, which must have space for at least
1146 * CORENAME_MAX_SIZE bytes plus one byte for the zero terminator.
1148 void format_corename(char *corename
, const char *pattern
, long signr
)
1150 const char *pat_ptr
= pattern
;
1151 char *out_ptr
= corename
;
1152 char *const out_end
= corename
+ CORENAME_MAX_SIZE
;
1154 int pid_in_pattern
= 0;
1156 /* Repeat as long as we have more pattern to process and more output
1159 if (*pat_ptr
!= '%') {
1160 if (out_ptr
== out_end
)
1162 *out_ptr
++ = *pat_ptr
++;
1164 switch (*++pat_ptr
) {
1167 /* Double percent, output one percent */
1169 if (out_ptr
== out_end
)
1176 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1177 "%d", current
->tgid
);
1178 if (rc
> out_end
- out_ptr
)
1184 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1185 "%d", current
->uid
);
1186 if (rc
> out_end
- out_ptr
)
1192 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1193 "%d", current
->gid
);
1194 if (rc
> out_end
- out_ptr
)
1198 /* signal that caused the coredump */
1200 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1202 if (rc
> out_end
- out_ptr
)
1206 /* UNIX time of coredump */
1209 do_gettimeofday(&tv
);
1210 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1212 if (rc
> out_end
- out_ptr
)
1219 down_read(&uts_sem
);
1220 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1221 "%s", system_utsname
.nodename
);
1223 if (rc
> out_end
- out_ptr
)
1229 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1230 "%s", current
->comm
);
1231 if (rc
> out_end
- out_ptr
)
1241 /* Backward compatibility with core_uses_pid:
1243 * If core_pattern does not include a %p (as is the default)
1244 * and core_uses_pid is set, then .%pid will be appended to
1247 && (core_uses_pid
|| atomic_read(¤t
->mm
->mm_users
) != 1)) {
1248 rc
= snprintf(out_ptr
, out_end
- out_ptr
,
1249 ".%d", current
->tgid
);
1250 if (rc
> out_end
- out_ptr
)
1258 static void zap_threads (struct mm_struct
*mm
)
1260 struct task_struct
*g
, *p
;
1262 read_lock(&tasklist_lock
);
1264 if (mm
== p
->mm
&& p
!= current
) {
1265 force_sig_specific(SIGKILL
, p
);
1268 while_each_thread(g
,p
);
1270 read_unlock(&tasklist_lock
);
1273 static void coredump_wait(struct mm_struct
*mm
)
1275 DECLARE_COMPLETION(startup_done
);
1277 mm
->core_waiters
++; /* let other threads block */
1278 mm
->core_startup_done
= &startup_done
;
1280 /* give other threads a chance to run: */
1284 if (--mm
->core_waiters
) {
1285 up_write(&mm
->mmap_sem
);
1286 wait_for_completion(&startup_done
);
1288 up_write(&mm
->mmap_sem
);
1289 BUG_ON(mm
->core_waiters
);
1292 int do_coredump(long signr
, int exit_code
, struct pt_regs
* regs
)
1294 char corename
[CORENAME_MAX_SIZE
+ 1];
1295 struct mm_struct
*mm
= current
->mm
;
1296 struct linux_binfmt
* binfmt
;
1297 struct inode
* inode
;
1302 binfmt
= current
->binfmt
;
1303 if (!binfmt
|| !binfmt
->core_dump
)
1305 down_write(&mm
->mmap_sem
);
1306 if (!mm
->dumpable
) {
1307 up_write(&mm
->mmap_sem
);
1311 init_completion(&mm
->core_done
);
1312 current
->signal
->group_exit
= 1;
1313 current
->signal
->group_exit_code
= exit_code
;
1316 if (current
->rlim
[RLIMIT_CORE
].rlim_cur
< binfmt
->min_coredump
)
1319 format_corename(corename
, core_pattern
, signr
);
1320 file
= filp_open(corename
, O_CREAT
| 2 | O_NOFOLLOW
, 0600);
1323 inode
= file
->f_dentry
->d_inode
;
1324 if (inode
->i_nlink
> 1)
1325 goto close_fail
; /* multiple links - don't dump */
1326 if (d_unhashed(file
->f_dentry
))
1329 if (!S_ISREG(inode
->i_mode
))
1333 if (!file
->f_op
->write
)
1335 if (do_truncate(file
->f_dentry
, 0) != 0)
1338 retval
= binfmt
->core_dump(signr
, regs
, file
);
1340 current
->signal
->group_exit_code
|= 0x80;
1342 filp_close(file
, NULL
);
1344 complete_all(&mm
->core_done
);