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 nd.intent.open.flags = O_RDONLY;
121 error = __user_walk(library, LOOKUP_FOLLOW|LOOKUP_OPEN, &nd);
126 if (!S_ISREG(nd.dentry->d_inode->i_mode))
129 error = permission(nd.dentry->d_inode, MAY_READ | MAY_EXEC, &nd);
133 file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
134 error = PTR_ERR(file);
140 struct linux_binfmt * fmt;
142 read_lock(&binfmt_lock);
143 for (fmt = formats ; fmt ; fmt = fmt->next) {
144 if (!fmt->load_shlib)
146 if (!try_module_get(fmt->module))
148 read_unlock(&binfmt_lock);
149 error = fmt->load_shlib(file);
150 read_lock(&binfmt_lock);
152 if (error != -ENOEXEC)
155 read_unlock(&binfmt_lock);
166 * count() counts the number of strings in array ARGV.
168 static int count(char __user * __user * argv, int max)
176 if (get_user(p, argv))
189 * 'copy_strings()' copies argument/environment strings from user
190 * memory to free pages in kernel mem. These are in a format ready
191 * to be put directly into the top of new user memory.
193 int copy_strings(int argc,char __user * __user * argv, struct linux_binprm *bprm)
195 struct page *kmapped_page = NULL;
204 if (get_user(str, argv+argc) ||
205 !(len = strnlen_user(str, bprm->p))) {
216 /* XXX: add architecture specific overflow check here. */
221 int offset, bytes_to_copy;
224 offset = pos % PAGE_SIZE;
226 page = bprm->page[i];
229 page = alloc_page(GFP_HIGHUSER);
230 bprm->page[i] = page;
238 if (page != kmapped_page) {
240 kunmap(kmapped_page);
242 kaddr = kmap(kmapped_page);
245 memset(kaddr, 0, offset);
246 bytes_to_copy = PAGE_SIZE - offset;
247 if (bytes_to_copy > len) {
250 memset(kaddr+offset+len, 0,
251 PAGE_SIZE-offset-len);
253 err = copy_from_user(kaddr+offset, str, bytes_to_copy);
259 pos += bytes_to_copy;
260 str += bytes_to_copy;
261 len -= bytes_to_copy;
267 kunmap(kmapped_page);
272 * Like copy_strings, but get argv and its values from kernel memory.
274 int copy_strings_kernel(int argc,char ** argv, struct linux_binprm *bprm)
277 mm_segment_t oldfs = get_fs();
279 r = copy_strings(argc, (char __user * __user *)argv, bprm);
286 * This routine is used to map in a page into an address space: needed by
287 * execve() for the initial stack and environment pages.
289 * tsk->mmap_sem is held for writing.
291 void put_dirty_page(struct task_struct *tsk, struct page *page,
292 unsigned long address, pgprot_t prot)
297 struct pte_chain *pte_chain;
299 if (page_count(page) != 1)
300 printk(KERN_ERR "mem_map disagrees with %p at %08lx\n",
303 pgd = pgd_offset(tsk->mm, address);
304 pte_chain = pte_chain_alloc(GFP_KERNEL);
307 spin_lock(&tsk->mm->page_table_lock);
308 pmd = pmd_alloc(tsk->mm, pgd, address);
311 pte = pte_alloc_map(tsk->mm, pmd, address);
314 if (!pte_none(*pte)) {
318 lru_cache_add_active(page);
319 flush_dcache_page(page);
320 set_pte(pte, pte_mkdirty(pte_mkwrite(mk_pte(page, prot))));
321 pte_chain = page_add_rmap(page, pte, pte_chain);
324 spin_unlock(&tsk->mm->page_table_lock);
326 /* no need for flush_tlb */
327 pte_chain_free(pte_chain);
330 spin_unlock(&tsk->mm->page_table_lock);
333 force_sig(SIGKILL, tsk);
334 pte_chain_free(pte_chain);
338 int setup_arg_pages(struct linux_binprm *bprm)
340 unsigned long stack_base;
341 struct vm_area_struct *mpnt;
342 struct mm_struct *mm = current->mm;
345 #ifdef CONFIG_STACK_GROWSUP
346 /* Move the argument and environment strings to the bottom of the
352 /* Start by shifting all the pages down */
354 for (j = 0; j < MAX_ARG_PAGES; j++) {
355 struct page *page = bprm->page[j];
358 bprm->page[i++] = page;
361 /* Now move them within their pages */
362 offset = bprm->p % PAGE_SIZE;
363 to = kmap(bprm->page[0]);
364 for (j = 1; j < i; j++) {
365 memmove(to, to + offset, PAGE_SIZE - offset);
366 from = kmap(bprm->page[j]);
367 memcpy(to + PAGE_SIZE - offset, from, offset);
368 kunmap(bprm->page[j - 1]);
371 memmove(to, to + offset, PAGE_SIZE - offset);
372 kunmap(bprm->page[j - 1]);
374 /* Adjust bprm->p to point to the end of the strings. */
375 bprm->p = PAGE_SIZE * i - offset;
376 stack_base = STACK_TOP - current->rlim[RLIMIT_STACK].rlim_max;
377 mm->arg_start = stack_base;
379 /* zero pages that were copied above */
380 while (i < MAX_ARG_PAGES)
381 bprm->page[i++] = NULL;
383 stack_base = STACK_TOP - MAX_ARG_PAGES * PAGE_SIZE;
384 mm->arg_start = bprm->p + stack_base;
387 bprm->p += stack_base;
389 bprm->loader += stack_base;
390 bprm->exec += stack_base;
392 mpnt = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
396 if (security_vm_enough_memory((STACK_TOP - (PAGE_MASK & (unsigned long) bprm->p))>>PAGE_SHIFT)) {
397 kmem_cache_free(vm_area_cachep, mpnt);
401 down_write(&mm->mmap_sem);
404 #ifdef CONFIG_STACK_GROWSUP
405 mpnt->vm_start = stack_base;
406 mpnt->vm_end = PAGE_MASK &
407 (PAGE_SIZE - 1 + (unsigned long) bprm->p);
409 mpnt->vm_start = PAGE_MASK & (unsigned long) bprm->p;
410 mpnt->vm_end = STACK_TOP;
412 mpnt->vm_page_prot = protection_map[VM_STACK_FLAGS & 0x7];
413 mpnt->vm_flags = VM_STACK_FLAGS;
416 mpnt->vm_file = NULL;
417 INIT_LIST_HEAD(&mpnt->shared);
418 mpnt->vm_private_data = (void *) 0;
419 insert_vm_struct(mm, mpnt);
420 mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
423 for (i = 0 ; i < MAX_ARG_PAGES ; i++) {
424 struct page *page = bprm->page[i];
426 bprm->page[i] = NULL;
427 put_dirty_page(current, page, stack_base,
430 stack_base += PAGE_SIZE;
432 up_write(&mm->mmap_sem);
437 #define free_arg_pages(bprm) do { } while (0)
441 static inline void free_arg_pages(struct linux_binprm *bprm)
445 for (i = 0; i < MAX_ARG_PAGES; i++) {
447 __free_page(bprm->page[i]);
448 bprm->page[i] = NULL;
452 #endif /* CONFIG_MMU */
454 struct file *open_exec(const char *name)
457 int err = path_lookup(name, LOOKUP_FOLLOW, &nd);
458 struct file *file = ERR_PTR(err);
461 struct inode *inode = nd.dentry->d_inode;
462 file = ERR_PTR(-EACCES);
463 if (!(nd.mnt->mnt_flags & MNT_NOEXEC) &&
464 S_ISREG(inode->i_mode)) {
465 int err = permission(inode, MAY_EXEC, &nd);
466 if (!err && !(inode->i_mode & 0111))
470 file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
472 err = deny_write_access(file);
487 int kernel_read(struct file *file, unsigned long offset,
488 char *addr, unsigned long count)
496 /* The cast to a user pointer is valid due to the set_fs() */
497 result = vfs_read(file, (void __user *)addr, count, &pos);
502 static int exec_mmap(struct mm_struct *mm)
504 struct task_struct *tsk;
505 struct mm_struct * old_mm, *active_mm;
507 /* Add it to the list of mm's */
508 spin_lock(&mmlist_lock);
509 list_add(&mm->mmlist, &init_mm.mmlist);
511 spin_unlock(&mmlist_lock);
513 /* Notify parent that we're no longer interested in the old VM */
515 old_mm = current->mm;
516 mm_release(tsk, old_mm);
519 active_mm = tsk->active_mm;
522 activate_mm(active_mm, mm);
525 if (active_mm != old_mm) BUG();
534 * This function makes sure the current process has its own signal table,
535 * so that flush_signal_handlers can later reset the handlers without
536 * disturbing other processes. (Other processes might share the signal
537 * table via the CLONE_SIGHAND option to clone().)
539 static inline int de_thread(struct task_struct *tsk)
541 struct signal_struct *newsig, *oldsig = tsk->signal;
542 struct sighand_struct *newsighand, *oldsighand = tsk->sighand;
543 spinlock_t *lock = &oldsighand->siglock;
547 * If we don't share sighandlers, then we aren't sharing anything
548 * and we can just re-use it all.
550 if (atomic_read(&oldsighand->count) <= 1)
553 newsighand = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);
557 spin_lock_init(&newsighand->siglock);
558 atomic_set(&newsighand->count, 1);
559 memcpy(newsighand->action, oldsighand->action, sizeof(newsighand->action));
562 * See if we need to allocate a new signal structure
565 if (atomic_read(&oldsig->count) > 1) {
566 newsig = kmem_cache_alloc(signal_cachep, GFP_KERNEL);
568 kmem_cache_free(sighand_cachep, newsighand);
571 atomic_set(&newsig->count, 1);
572 newsig->group_exit = 0;
573 newsig->group_exit_code = 0;
574 newsig->group_exit_task = NULL;
575 newsig->group_stop_count = 0;
576 newsig->curr_target = NULL;
577 init_sigpending(&newsig->shared_pending);
580 if (thread_group_empty(current))
581 goto no_thread_group;
584 * Kill all other threads in the thread group.
585 * We must hold tasklist_lock to call zap_other_threads.
587 read_lock(&tasklist_lock);
589 if (oldsig->group_exit) {
591 * Another group action in progress, just
592 * return so that the signal is processed.
594 spin_unlock_irq(lock);
595 read_unlock(&tasklist_lock);
596 kmem_cache_free(sighand_cachep, newsighand);
598 kmem_cache_free(signal_cachep, newsig);
601 oldsig->group_exit = 1;
602 zap_other_threads(current);
603 read_unlock(&tasklist_lock);
606 * Account for the thread group leader hanging around:
609 if (current->pid == current->tgid)
611 while (atomic_read(&oldsig->count) > count) {
612 oldsig->group_exit_task = current;
613 oldsig->notify_count = count;
614 __set_current_state(TASK_UNINTERRUPTIBLE);
615 spin_unlock_irq(lock);
619 spin_unlock_irq(lock);
622 * At this point all other threads have exited, all we have to
623 * do is to wait for the thread group leader to become inactive,
624 * and to assume its PID:
626 if (current->pid != current->tgid) {
627 struct task_struct *leader = current->group_leader, *parent;
628 struct dentry *proc_dentry1, *proc_dentry2;
629 unsigned long state, ptrace;
632 * Wait for the thread group leader to be a zombie.
633 * It should already be zombie at this point, most
636 while (leader->state != TASK_ZOMBIE)
639 spin_lock(&leader->proc_lock);
640 spin_lock(¤t->proc_lock);
641 proc_dentry1 = proc_pid_unhash(current);
642 proc_dentry2 = proc_pid_unhash(leader);
643 write_lock_irq(&tasklist_lock);
645 if (leader->tgid != current->tgid)
647 if (current->pid == current->tgid)
650 * An exec() starts a new thread group with the
651 * TGID of the previous thread group. Rehash the
652 * two threads with a switched PID, and release
653 * the former thread group leader:
655 ptrace = leader->ptrace;
656 parent = leader->parent;
658 ptrace_unlink(current);
659 ptrace_unlink(leader);
660 remove_parent(current);
661 remove_parent(leader);
663 switch_exec_pids(leader, current);
665 current->parent = current->real_parent = leader->real_parent;
666 leader->parent = leader->real_parent = child_reaper;
667 current->group_leader = current;
668 leader->group_leader = leader;
670 add_parent(current, current->parent);
671 add_parent(leader, leader->parent);
673 current->ptrace = ptrace;
674 __ptrace_link(current, parent);
677 list_del(¤t->tasks);
678 list_add_tail(¤t->tasks, &init_task.tasks);
679 current->exit_signal = SIGCHLD;
680 state = leader->state;
682 write_unlock_irq(&tasklist_lock);
683 spin_unlock(&leader->proc_lock);
684 spin_unlock(¤t->proc_lock);
685 proc_pid_flush(proc_dentry1);
686 proc_pid_flush(proc_dentry2);
688 if (state != TASK_ZOMBIE)
690 release_task(leader);
695 write_lock_irq(&tasklist_lock);
696 spin_lock(&oldsighand->siglock);
697 spin_lock(&newsighand->siglock);
699 if (current == oldsig->curr_target)
700 oldsig->curr_target = next_thread(current);
702 current->signal = newsig;
703 current->sighand = newsighand;
704 init_sigpending(¤t->pending);
707 spin_unlock(&newsighand->siglock);
708 spin_unlock(&oldsighand->siglock);
709 write_unlock_irq(&tasklist_lock);
711 if (newsig && atomic_dec_and_test(&oldsig->count))
712 kmem_cache_free(signal_cachep, oldsig);
714 if (atomic_dec_and_test(&oldsighand->count))
715 kmem_cache_free(sighand_cachep, oldsighand);
717 if (!thread_group_empty(current))
719 if (current->tgid != current->pid)
725 * These functions flushes out all traces of the currently running executable
726 * so that a new one can be started
729 static inline void flush_old_files(struct files_struct * files)
733 spin_lock(&files->file_lock);
735 unsigned long set, i;
739 if (i >= files->max_fds || i >= files->max_fdset)
741 set = files->close_on_exec->fds_bits[j];
744 files->close_on_exec->fds_bits[j] = 0;
745 spin_unlock(&files->file_lock);
746 for ( ; set ; i++,set >>= 1) {
751 spin_lock(&files->file_lock);
754 spin_unlock(&files->file_lock);
757 int flush_old_exec(struct linux_binprm * bprm)
763 * Make sure we have a private signal table and that
764 * we are unassociated from the previous thread group.
766 retval = de_thread(current);
771 * Release all of the old mmap stuff
773 retval = exec_mmap(bprm->mm);
777 bprm->mm = NULL; /* We're using it now */
779 /* This is the point of no return */
781 current->sas_ss_sp = current->sas_ss_size = 0;
783 if (current->euid == current->uid && current->egid == current->gid)
784 current->mm->dumpable = 1;
785 name = bprm->filename;
786 for (i=0; (ch = *(name++)) != '\0';) {
791 current->comm[i++] = ch;
793 current->comm[i] = '\0';
797 if (bprm->e_uid != current->euid || bprm->e_gid != current->egid ||
798 permission(bprm->file->f_dentry->d_inode,MAY_READ, NULL))
799 current->mm->dumpable = 0;
801 /* An exec changes our domain. We are no longer part of the thread
804 current->self_exec_id++;
806 flush_signal_handlers(current, 0);
807 flush_old_files(current->files);
808 exit_itimers(current);
817 * We mustn't allow tracing of suid binaries, unless
818 * the tracer has the capability to trace anything..
820 static inline int must_not_trace_exec(struct task_struct * p)
822 return (p->ptrace & PT_PTRACED) && !(p->ptrace & PT_PTRACE_CAP);
826 * Fill the binprm structure from the inode.
827 * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes
829 int prepare_binprm(struct linux_binprm *bprm)
832 struct inode * inode = bprm->file->f_dentry->d_inode;
835 mode = inode->i_mode;
837 * Check execute perms again - if the caller has CAP_DAC_OVERRIDE,
838 * vfs_permission lets a non-executable through
840 if (!(mode & 0111)) /* with at least _one_ execute bit set */
842 if (bprm->file->f_op == NULL)
845 bprm->e_uid = current->euid;
846 bprm->e_gid = current->egid;
848 if(!(bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)) {
851 bprm->e_uid = inode->i_uid;
855 * If setgid is set but no group execute bit then this
856 * is a candidate for mandatory locking, not a setgid
859 if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP))
860 bprm->e_gid = inode->i_gid;
863 /* fill in binprm security blob */
864 retval = security_bprm_set(bprm);
868 memset(bprm->buf,0,BINPRM_BUF_SIZE);
869 return kernel_read(bprm->file,0,bprm->buf,BINPRM_BUF_SIZE);
873 * This function is used to produce the new IDs and capabilities
874 * from the old ones and the file's capabilities.
876 * The formula used for evolving capabilities is:
879 * (***) pP' = (fP & X) | (fI & pI)
880 * pE' = pP' & fE [NB. fE is 0 or ~0]
882 * I=Inheritable, P=Permitted, E=Effective // p=process, f=file
883 * ' indicates post-exec(), and X is the global 'cap_bset'.
887 void compute_creds(struct linux_binprm *bprm)
890 if (bprm->e_uid != current->uid || bprm->e_gid != current->gid) {
891 current->mm->dumpable = 0;
893 if (must_not_trace_exec(current)
894 || atomic_read(¤t->fs->count) > 1
895 || atomic_read(¤t->files->count) > 1
896 || atomic_read(¤t->sighand->count) > 1) {
897 if(!capable(CAP_SETUID)) {
898 bprm->e_uid = current->uid;
899 bprm->e_gid = current->gid;
904 current->suid = current->euid = current->fsuid = bprm->e_uid;
905 current->sgid = current->egid = current->fsgid = bprm->e_gid;
907 task_unlock(current);
909 security_bprm_compute_creds(bprm);
912 void remove_arg_zero(struct linux_binprm *bprm)
915 unsigned long offset;
919 offset = bprm->p % PAGE_SIZE;
922 while (bprm->p++, *(kaddr+offset++)) {
923 if (offset != PAGE_SIZE)
926 kunmap_atomic(kaddr, KM_USER0);
928 page = bprm->page[bprm->p/PAGE_SIZE];
929 kaddr = kmap_atomic(page, KM_USER0);
931 kunmap_atomic(kaddr, KM_USER0);
937 * cycle the list of binary formats handler, until one recognizes the image
939 int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs)
942 struct linux_binfmt *fmt;
944 /* handle /sbin/loader.. */
946 struct exec * eh = (struct exec *) bprm->buf;
948 if (!bprm->loader && eh->fh.f_magic == 0x183 &&
949 (eh->fh.f_flags & 0x3000) == 0x3000)
952 unsigned long loader;
954 allow_write_access(bprm->file);
958 loader = PAGE_SIZE*MAX_ARG_PAGES-sizeof(void *);
960 file = open_exec("/sbin/loader");
961 retval = PTR_ERR(file);
965 /* Remember if the application is TASO. */
966 bprm->sh_bang = eh->ah.entry < 0x100000000;
969 bprm->loader = loader;
970 retval = prepare_binprm(bprm);
973 /* should call search_binary_handler recursively here,
974 but it does not matter */
978 retval = security_bprm_check(bprm);
982 /* kernel module loader fixup */
983 /* so we don't try to load run modprobe in kernel space. */
985 for (try=0; try<2; try++) {
986 read_lock(&binfmt_lock);
987 for (fmt = formats ; fmt ; fmt = fmt->next) {
988 int (*fn)(struct linux_binprm *, struct pt_regs *) = fmt->load_binary;
991 if (!try_module_get(fmt->module))
993 read_unlock(&binfmt_lock);
994 retval = fn(bprm, regs);
997 allow_write_access(bprm->file);
1001 current->did_exec = 1;
1004 read_lock(&binfmt_lock);
1006 if (retval != -ENOEXEC || bprm->mm == NULL)
1009 read_unlock(&binfmt_lock);
1013 read_unlock(&binfmt_lock);
1014 if (retval != -ENOEXEC || bprm->mm == NULL) {
1018 #define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e))
1019 if (printable(bprm->buf[0]) &&
1020 printable(bprm->buf[1]) &&
1021 printable(bprm->buf[2]) &&
1022 printable(bprm->buf[3]))
1023 break; /* -ENOEXEC */
1024 request_module("binfmt-%04x", *(unsigned short *)(&bprm->buf[2]));
1032 * sys_execve() executes a new program.
1034 int do_execve(char * filename,
1035 char __user *__user *argv,
1036 char __user *__user *envp,
1037 struct pt_regs * regs)
1039 struct linux_binprm bprm;
1043 sched_balance_exec();
1045 file = open_exec(filename);
1047 retval = PTR_ERR(file);
1051 bprm.p = PAGE_SIZE*MAX_ARG_PAGES-sizeof(void *);
1052 memset(bprm.page, 0, MAX_ARG_PAGES*sizeof(bprm.page[0]));
1055 bprm.filename = filename;
1059 bprm.security = NULL;
1060 bprm.mm = mm_alloc();
1065 retval = init_new_context(current, bprm.mm);
1069 bprm.argc = count(argv, bprm.p / sizeof(void *));
1070 if ((retval = bprm.argc) < 0)
1073 bprm.envc = count(envp, bprm.p / sizeof(void *));
1074 if ((retval = bprm.envc) < 0)
1077 retval = security_bprm_alloc(&bprm);
1081 retval = prepare_binprm(&bprm);
1085 retval = copy_strings_kernel(1, &bprm.filename, &bprm);
1090 retval = copy_strings(bprm.envc, envp, &bprm);
1094 retval = copy_strings(bprm.argc, argv, &bprm);
1098 retval = search_binary_handler(&bprm,regs);
1100 free_arg_pages(&bprm);
1102 /* execve success */
1103 security_bprm_free(&bprm);
1108 /* Something went wrong, return the inode and free the argument pages*/
1109 free_arg_pages(&bprm);
1112 security_bprm_free(&bprm);
1120 allow_write_access(bprm.file);
1126 int set_binfmt(struct linux_binfmt *new)
1128 struct linux_binfmt *old = current->binfmt;
1131 if (!try_module_get(new->module))
1134 current->binfmt = new;
1136 module_put(old->module);
1140 #define CORENAME_MAX_SIZE 64
1142 /* format_corename will inspect the pattern parameter, and output a
1143 * name into corename, which must have space for at least
1144 * CORENAME_MAX_SIZE bytes plus one byte for the zero terminator.
1146 void format_corename(char *corename, const char *pattern, long signr)
1148 const char *pat_ptr = pattern;
1149 char *out_ptr = corename;
1150 char *const out_end = corename + CORENAME_MAX_SIZE;
1152 int pid_in_pattern = 0;
1154 /* Repeat as long as we have more pattern to process and more output
1157 if (*pat_ptr != '%') {
1158 if (out_ptr == out_end)
1160 *out_ptr++ = *pat_ptr++;
1162 switch (*++pat_ptr) {
1165 /* Double percent, output one percent */
1167 if (out_ptr == out_end)
1174 rc = snprintf(out_ptr, out_end - out_ptr,
1175 "%d", current->tgid);
1176 if (rc > out_end - out_ptr)
1182 rc = snprintf(out_ptr, out_end - out_ptr,
1183 "%d", current->uid);
1184 if (rc > out_end - out_ptr)
1190 rc = snprintf(out_ptr, out_end - out_ptr,
1191 "%d", current->gid);
1192 if (rc > out_end - out_ptr)
1196 /* signal that caused the coredump */
1198 rc = snprintf(out_ptr, out_end - out_ptr,
1200 if (rc > out_end - out_ptr)
1204 /* UNIX time of coredump */
1207 do_gettimeofday(&tv);
1208 rc = snprintf(out_ptr, out_end - out_ptr,
1210 if (rc > out_end - out_ptr)
1217 down_read(&uts_sem);
1218 rc = snprintf(out_ptr, out_end - out_ptr,
1219 "%s", system_utsname.nodename);
1221 if (rc > out_end - out_ptr)
1227 rc = snprintf(out_ptr, out_end - out_ptr,
1228 "%s", current->comm);
1229 if (rc > out_end - out_ptr)
1239 /* Backward compatibility with core_uses_pid:
1241 * If core_pattern does not include a %p (as is the default)
1242 * and core_uses_pid is set, then .%pid will be appended to
1245 && (core_uses_pid || atomic_read(¤t->mm->mm_users) != 1)) {
1246 rc = snprintf(out_ptr, out_end - out_ptr,
1247 ".%d", current->tgid);
1248 if (rc > out_end - out_ptr)
1256 static void zap_threads (struct mm_struct *mm)
1258 struct task_struct *g, *p;
1259 struct task_struct *tsk = current;
1260 struct completion *vfork_done = tsk->vfork_done;
1263 * Make sure nobody is waiting for us to release the VM,
1264 * otherwise we can deadlock when we wait on each other
1267 tsk->vfork_done = NULL;
1268 complete(vfork_done);
1271 read_lock(&tasklist_lock);
1273 if (mm == p->mm && p != tsk) {
1274 force_sig_specific(SIGKILL, p);
1277 while_each_thread(g,p);
1279 read_unlock(&tasklist_lock);
1282 static void coredump_wait(struct mm_struct *mm)
1284 DECLARE_COMPLETION(startup_done);
1286 mm->core_waiters++; /* let other threads block */
1287 mm->core_startup_done = &startup_done;
1289 /* give other threads a chance to run: */
1293 if (--mm->core_waiters) {
1294 up_write(&mm->mmap_sem);
1295 wait_for_completion(&startup_done);
1297 up_write(&mm->mmap_sem);
1298 BUG_ON(mm->core_waiters);
1301 int do_coredump(long signr, int exit_code, struct pt_regs * regs)
1303 char corename[CORENAME_MAX_SIZE + 1];
1304 struct mm_struct *mm = current->mm;
1305 struct linux_binfmt * binfmt;
1306 struct inode * inode;
1311 binfmt = current->binfmt;
1312 if (!binfmt || !binfmt->core_dump)
1314 down_write(&mm->mmap_sem);
1315 if (!mm->dumpable) {
1316 up_write(&mm->mmap_sem);
1320 init_completion(&mm->core_done);
1321 current->signal->group_exit = 1;
1322 current->signal->group_exit_code = exit_code;
1325 if (current->rlim[RLIMIT_CORE].rlim_cur < binfmt->min_coredump)
1328 format_corename(corename, core_pattern, signr);
1329 file = filp_open(corename, O_CREAT | 2 | O_NOFOLLOW, 0600);
1332 inode = file->f_dentry->d_inode;
1333 if (inode->i_nlink > 1)
1334 goto close_fail; /* multiple links - don't dump */
1335 if (d_unhashed(file->f_dentry))
1338 if (!S_ISREG(inode->i_mode))
1342 if (!file->f_op->write)
1344 if (do_truncate(file->f_dentry, 0) != 0)
1347 retval = binfmt->core_dump(signr, regs, file);
1349 current->signal->group_exit_code |= 0x80;
1351 filp_close(file, NULL);
1353 complete_all(&mm->core_done);