/* * linux/fs/exec.c * * Copyright (C) 1991, 1992 Linus Torvalds */ /* * #!-checking implemented by tytso. */ /* * Demand-loading implemented 01.12.91 - no need to read anything but * the header into memory. The inode of the executable is put into * "current->executable", and page faults do the actual loading. Clean. * * Once more I can proudly say that linux stood up to being changed: it * was less than 2 hours work to get demand-loading completely implemented. * * Demand loading changed July 1993 by Eric Youngdale. Use mmap instead, * current->executable is only used by the procfs. This allows a dispatch * table to check for several different types of binary formats. We keep * trying until we recognize the file or we run out of supported binary * formats. */ #include <linux/config.h> #include <linux/slab.h> #include <linux/file.h> #include <linux/mman.h> #include <linux/a.out.h> #include <linux/stat.h> #include <linux/fcntl.h> #include <linux/smp_lock.h> #include <linux/init.h> #include <linux/pagemap.h> #include <linux/highmem.h> #include <linux/spinlock.h> #define __NO_VERSION__ #include <linux/module.h> #include <asm/uaccess.h> #include <asm/pgalloc.h> #include <asm/mmu_context.h> #ifdef CONFIG_KMOD #include <linux/kmod.h> #endif static struct linux_binfmt *formats; static rwlock_t binfmt_lock = RW_LOCK_UNLOCKED; 51 int register_binfmt(struct linux_binfmt * fmt) { struct linux_binfmt ** tmp = &formats; 55 if (!fmt) 56 return -EINVAL; 57 if (fmt->next) 58 return -EBUSY; write_lock(&binfmt_lock); 60 while (*tmp) { 61 if (fmt == *tmp) { 62 write_unlock(&binfmt_lock); 63 return -EBUSY; } tmp = &(*tmp)->next; } fmt->next = formats; formats = fmt; 69 write_unlock(&binfmt_lock); 70 return 0; } 73 int unregister_binfmt(struct linux_binfmt * fmt) { struct linux_binfmt ** tmp = &formats; write_lock(&binfmt_lock); 78 while (*tmp) { 79 if (fmt == *tmp) { *tmp = fmt->next; 81 write_unlock(&binfmt_lock); 82 return 0; } tmp = &(*tmp)->next; } 86 write_unlock(&binfmt_lock); 87 return -EINVAL; } 90 static inline void put_binfmt(struct linux_binfmt * fmt) { 92 if (fmt->module) __MOD_DEC_USE_COUNT(fmt->module); } /* * Note that a shared library must be both readable and executable due to * security reasons. * * Also note that we take the address to load from from the file itself. */ 102 asmlinkage long sys_uselib(const char * library) { struct file * file; struct nameidata nd; int error; error = user_path_walk(library, &nd); 109 if (error) 110 goto out; error = -EINVAL; 113 if (!S_ISREG(nd.dentry->d_inode->i_mode)) 114 goto exit; error = permission(nd.dentry->d_inode, MAY_READ | MAY_EXEC); 117 if (error) 118 goto exit; file = dentry_open(nd.dentry, nd.mnt, O_RDONLY); error = PTR_ERR(file); 122 if (IS_ERR(file)) 123 goto out; error = -ENOEXEC; 126 if(file->f_op && file->f_op->read) { struct linux_binfmt * fmt; read_lock(&binfmt_lock); 130 for (fmt = formats ; fmt ; fmt = fmt->next) { 131 if (!fmt->load_shlib) 132 continue; 133 if (!try_inc_mod_count(fmt->module)) 134 continue; 135 read_unlock(&binfmt_lock); error = fmt->load_shlib(file); read_lock(&binfmt_lock); put_binfmt(fmt); 139 if (error != -ENOEXEC) 140 break; } 142 read_unlock(&binfmt_lock); } fput(file); out: 146 return error; exit: path_release(&nd); 149 goto out; } /* * count() counts the number of arguments/envelopes */ 155 static int count(char ** argv, int max) { int i = 0; 159 if (argv != NULL) { 160 for (;;) { char * p; int error; error = get_user(p,argv); 165 if (error) 166 return error; 167 if (!p) 168 break; argv++; 170 if(++i > max) 171 return -E2BIG; } } 174 return i; } /* * 'copy_strings()' copies argument/envelope strings from user * memory to free pages in kernel mem. These are in a format ready * to be put directly into the top of new user memory. */ 182 int copy_strings(int argc,char ** argv, struct linux_binprm *bprm) { 184 while (argc-- > 0) { char *str; int len; unsigned long pos; 189 if (get_user(str, argv+argc) || !str || !(len = strnlen_user(str, bprm->p))) 190 return -EFAULT; 191 if (bprm->p < len) 192 return -E2BIG; bprm->p -= len; /* XXX: add architecture specific overflow check here. */ pos = bprm->p; 198 while (len > 0) { char *kaddr; int i, new, err; struct page *page; int offset, bytes_to_copy; offset = pos % PAGE_SIZE; i = pos/PAGE_SIZE; page = bprm->page[i]; new = 0; 208 if (!page) { page = alloc_page(GFP_HIGHUSER); bprm->page[i] = page; 211 if (!page) 212 return -ENOMEM; new = 1; } kaddr = kmap(page); 217 if (new && offset) memset(kaddr, 0, offset); bytes_to_copy = PAGE_SIZE - offset; 220 if (bytes_to_copy > len) { bytes_to_copy = len; 222 if (new) memset(kaddr+offset+len, 0, PAGE_SIZE-offset-len); } err = copy_from_user(kaddr + offset, str, bytes_to_copy); 226 kunmap(page); 228 if (err) 229 return -EFAULT; pos += bytes_to_copy; str += bytes_to_copy; len -= bytes_to_copy; } } 236 return 0; } /* * Like copy_strings, but get argv and its values from kernel memory. */ 242 int copy_strings_kernel(int argc,char ** argv, struct linux_binprm *bprm) { int r; mm_segment_t oldfs = get_fs(); set_fs(KERNEL_DS); r = copy_strings(argc, argv, bprm); set_fs(oldfs); 249 return r; } /* * This routine is used to map in a page into an address space: needed by * execve() for the initial stack and environment pages. */ 256 void put_dirty_page(struct task_struct * tsk, struct page *page, unsigned long address) { pgd_t * pgd; pmd_t * pmd; pte_t * pte; 262 if (page_count(page) != 1) printk("mem_map disagrees with %p at %08lx\n", page, address); pgd = pgd_offset(tsk->mm, address); pmd = pmd_alloc(pgd, address); 266 if (!pmd) { __free_page(page); force_sig(SIGKILL, tsk); 269 return; } pte = pte_alloc(pmd, address); 272 if (!pte) { __free_page(page); force_sig(SIGKILL, tsk); 275 return; } 277 if (!pte_none(*pte)) { pte_ERROR(*pte); __free_page(page); 280 return; } 282 flush_dcache_page(page); 283 flush_page_to_ram(page); set_pte(pte, pte_mkdirty(pte_mkwrite(mk_pte(page, PAGE_COPY)))); /* no need for flush_tlb */ } 288 int setup_arg_pages(struct linux_binprm *bprm) { unsigned long stack_base; struct vm_area_struct *mpnt; int i; stack_base = STACK_TOP - MAX_ARG_PAGES*PAGE_SIZE; bprm->p += stack_base; 297 if (bprm->loader) bprm->loader += stack_base; bprm->exec += stack_base; mpnt = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL); 302 if (!mpnt) 303 return -ENOMEM; down(¤t->mm->mmap_sem); { mpnt->vm_mm = current->mm; mpnt->vm_start = PAGE_MASK & (unsigned long) bprm->p; mpnt->vm_end = STACK_TOP; mpnt->vm_page_prot = PAGE_COPY; mpnt->vm_flags = VM_STACK_FLAGS; mpnt->vm_ops = NULL; mpnt->vm_pgoff = 0; mpnt->vm_file = NULL; mpnt->vm_private_data = (void *) 0; insert_vm_struct(current->mm, mpnt); current->mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT; } 320 for (i = 0 ; i < MAX_ARG_PAGES ; i++) { struct page *page = bprm->page[i]; 322 if (page) { bprm->page[i] = NULL; current->mm->rss++; put_dirty_page(current,page,stack_base); } stack_base += PAGE_SIZE; } up(¤t->mm->mmap_sem); 331 return 0; } 334 struct file *open_exec(const char *name) { struct nameidata nd; struct inode *inode; struct file *file; int err = 0; 341 if (path_init(name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, &nd)) err = path_walk(name, &nd); file = ERR_PTR(err); 344 if (!err) { inode = nd.dentry->d_inode; file = ERR_PTR(-EACCES); 347 if (!IS_NOEXEC(inode) && S_ISREG(inode->i_mode)) { int err = permission(inode, MAY_EXEC); file = ERR_PTR(err); 350 if (!err) { file = dentry_open(nd.dentry, nd.mnt, O_RDONLY); 352 if (!IS_ERR(file)) { err = deny_write_access(file); 354 if (err) { fput(file); file = ERR_PTR(err); } } out: 360 return file; } } path_release(&nd); } 365 goto out; } 368 int kernel_read(struct file *file, unsigned long offset, char * addr, unsigned long count) { mm_segment_t old_fs; loff_t pos = offset; int result = -ENOSYS; 375 if (!file->f_op->read) 376 goto fail; old_fs = get_fs(); set_fs(get_ds()); result = file->f_op->read(file, addr, count, &pos); set_fs(old_fs); fail: 382 return result; } 385 static int exec_mmap(void) { struct mm_struct * mm, * old_mm; old_mm = current->mm; 390 if (old_mm && atomic_read(&old_mm->mm_users) == 1) { 391 flush_cache_mm(old_mm); mm_release(); exit_mmap(old_mm); flush_tlb_mm(old_mm); 395 return 0; } mm = mm_alloc(); 399 if (mm) { struct mm_struct *active_mm = current->active_mm; 402 if (init_new_context(current, mm)) { mmdrop(mm); 404 return -ENOMEM; } /* Add it to the list of mm's */ spin_lock(&mmlist_lock); list_add(&mm->mmlist, &init_mm.mmlist); 410 spin_unlock(&mmlist_lock); task_lock(current); current->mm = mm; current->active_mm = mm; task_unlock(current); activate_mm(active_mm, mm); mm_release(); 418 if (old_mm) { 419 if (active_mm != old_mm) BUG(); mmput(old_mm); 421 return 0; } mmdrop(active_mm); 424 return 0; } 426 return -ENOMEM; } /* * This function makes sure the current process has its own signal table, * so that flush_signal_handlers can later reset the handlers without * disturbing other processes. (Other processes might share the signal * table via the CLONE_SIGNAL option to clone().) */ 436 static inline int make_private_signals(void) { struct signal_struct * newsig; 440 if (atomic_read(¤t->sig->count) <= 1) 441 return 0; newsig = kmem_cache_alloc(sigact_cachep, GFP_KERNEL); 443 if (newsig == NULL) 444 return -ENOMEM; 445 spin_lock_init(&newsig->siglock); atomic_set(&newsig->count, 1); memcpy(newsig->action, current->sig->action, sizeof(newsig->action)); 448 spin_lock_irq(¤t->sigmask_lock); current->sig = newsig; 450 spin_unlock_irq(¤t->sigmask_lock); 451 return 0; } /* * If make_private_signals() made a copy of the signal table, decrement the * refcount of the original table, and free it if necessary. * We don't do that in make_private_signals() so that we can back off * in flush_old_exec() if an error occurs after calling make_private_signals(). */ 461 static inline void release_old_signals(struct signal_struct * oldsig) { 463 if (current->sig == oldsig) 464 return; 465 if (atomic_dec_and_test(&oldsig->count)) kmem_cache_free(sigact_cachep, oldsig); } /* * These functions flushes out all traces of the currently running executable * so that a new one can be started */ 474 static inline void flush_old_files(struct files_struct * files) { long j = -1; write_lock(&files->file_lock); 479 for (;;) { unsigned long set, i; j++; i = j * __NFDBITS; 484 if (i >= files->max_fds || i >= files->max_fdset) 485 break; set = files->close_on_exec->fds_bits[j]; 487 if (!set) 488 continue; files->close_on_exec->fds_bits[j] = 0; 490 write_unlock(&files->file_lock); 491 for ( ; set ; i++,set >>= 1) { 492 if (set & 1) { sys_close(i); } } write_lock(&files->file_lock); } 499 write_unlock(&files->file_lock); } /* * An execve() will automatically "de-thread" the process. * Note: we don't have to hold the tasklist_lock to test * whether we migth need to do this. If we're not part of * a thread group, there is no way we can become one * dynamically. And if we are, we only need to protect the * unlink - even if we race with the last other thread exit, * at worst the list_del_init() might end up being a no-op. */ 511 static inline void de_thread(struct task_struct *tsk) { 513 if (!list_empty(&tsk->thread_group)) { 514 write_lock_irq(&tasklist_lock); list_del_init(&tsk->thread_group); 516 write_unlock_irq(&tasklist_lock); } /* Minor oddity: this might stay the same. */ tsk->tgid = tsk->pid; } 523 int flush_old_exec(struct linux_binprm * bprm) { char * name; int i, ch, retval; struct signal_struct * oldsig; /* * Make sure we have a private signal table */ oldsig = current->sig; retval = make_private_signals(); 534 if (retval) goto flush_failed; /* * Release all of the old mmap stuff */ retval = exec_mmap(); 540 if (retval) goto mmap_failed; /* This is the point of no return */ release_old_signals(oldsig); current->sas_ss_sp = current->sas_ss_size = 0; 547 if (current->euid == current->uid && current->egid == current->gid) current->dumpable = 1; name = bprm->filename; 550 for (i=0; (ch = *(name++)) != '\0';) { 551 if (ch == '/') i = 0; else 554 if (i < 15) current->comm[i++] = ch; } current->comm[i] = '\0'; flush_thread(); de_thread(current); if (bprm->e_uid != current->euid || bprm->e_gid != current->egid || 564 permission(bprm->file->f_dentry->d_inode,MAY_READ)) current->dumpable = 0; /* An exec changes our domain. We are no longer part of the thread group */ current->self_exec_id++; flush_signal_handlers(current); flush_old_files(current->files); 575 return 0; mmap_failed: flush_failed: 579 spin_lock_irq(¤t->sigmask_lock); 580 if (current->sig != oldsig) kfree(current->sig); current->sig = oldsig; 583 spin_unlock_irq(¤t->sigmask_lock); 584 return retval; } /* * We mustn't allow tracing of suid binaries, unless * the tracer has the capability to trace anything.. */ 591 static inline int must_not_trace_exec(struct task_struct * p) { 593 return (p->ptrace & PT_PTRACED) && !cap_raised(p->p_pptr->cap_effective, CAP_SYS_PTRACE); } /* * Fill the binprm structure from the inode. * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes */ 600 int prepare_binprm(struct linux_binprm *bprm) { int mode; struct inode * inode = bprm->file->f_dentry->d_inode; mode = inode->i_mode; /* Huh? We had already checked for MAY_EXEC, WTF do we check this? */ 607 if (!(mode & 0111)) /* with at least _one_ execute bit set */ 608 return -EACCES; 609 if (bprm->file->f_op == NULL) 610 return -EACCES; bprm->e_uid = current->euid; bprm->e_gid = current->egid; 615 if(!IS_NOSUID(inode)) { /* Set-uid? */ 617 if (mode & S_ISUID) bprm->e_uid = inode->i_uid; /* Set-gid? */ /* * If setgid is set but no group execute bit then this * is a candidate for mandatory locking, not a setgid * executable. */ 626 if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) bprm->e_gid = inode->i_gid; } /* We don't have VFS support for capabilities yet */ 631 cap_clear(bprm->cap_inheritable); 632 cap_clear(bprm->cap_permitted); 633 cap_clear(bprm->cap_effective); /* To support inheritance of root-permissions and suid-root * executables under compatibility mode, we raise all three * capability sets for the file. * * If only the real uid is 0, we only raise the inheritable * and permitted sets of the executable file. */ 643 if (!issecure(SECURE_NOROOT)) { 644 if (bprm->e_uid == 0 || current->uid == 0) { 645 cap_set_full(bprm->cap_inheritable); 646 cap_set_full(bprm->cap_permitted); } 648 if (bprm->e_uid == 0) 649 cap_set_full(bprm->cap_effective); } memset(bprm->buf,0,BINPRM_BUF_SIZE); 653 return kernel_read(bprm->file,0,bprm->buf,BINPRM_BUF_SIZE); } /* * This function is used to produce the new IDs and capabilities * from the old ones and the file's capabilities. * * The formula used for evolving capabilities is: * * pI' = pI * (***) pP' = (fP & X) | (fI & pI) * pE' = pP' & fE [NB. fE is 0 or ~0] * * I=Inheritable, P=Permitted, E=Effective // p=process, f=file * ' indicates post-exec(), and X is the global 'cap_bset'. * */ 671 void compute_creds(struct linux_binprm *bprm) { kernel_cap_t new_permitted, working; int do_unlock = 0; new_permitted = cap_intersect(bprm->cap_permitted, cap_bset); working = cap_intersect(bprm->cap_inheritable, current->cap_inheritable); new_permitted = cap_combine(new_permitted, working); if (bprm->e_uid != current->uid || bprm->e_gid != current->gid || 682 !cap_issubset(new_permitted, current->cap_permitted)) { current->dumpable = 0; 685 lock_kernel(); if (must_not_trace_exec(current) || atomic_read(¤t->fs->count) > 1 || atomic_read(¤t->files->count) > 1 689 || atomic_read(¤t->sig->count) > 1) { 690 if(!capable(CAP_SETUID)) { bprm->e_uid = current->uid; bprm->e_gid = current->gid; } 694 if(!capable(CAP_SETPCAP)) { new_permitted = cap_intersect(new_permitted, current->cap_permitted); } } do_unlock = 1; } /* For init, we want to retain the capabilities set * in the init_task struct. Thus we skip the usual * capability rules */ 706 if (current->pid != 1) { current->cap_permitted = new_permitted; current->cap_effective = cap_intersect(new_permitted, bprm->cap_effective); } /* AUD: Audit candidate if current->cap_effective is set */ current->suid = current->euid = current->fsuid = bprm->e_uid; current->sgid = current->egid = current->fsgid = bprm->e_gid; 717 if(do_unlock) 718 unlock_kernel(); current->keep_capabilities = 0; } 723 void remove_arg_zero(struct linux_binprm *bprm) { 725 if (bprm->argc) { unsigned long offset; char * kaddr; struct page *page; offset = bprm->p % PAGE_SIZE; 731 goto inside; 733 while (bprm->p++, *(kaddr+offset++)) { 734 if (offset != PAGE_SIZE) 735 continue; offset = 0; 737 kunmap(page); inside: page = bprm->page[bprm->p/PAGE_SIZE]; kaddr = kmap(page); } 742 kunmap(page); bprm->argc--; } } /* * cycle the list of binary formats handler, until one recognizes the image */ 750 int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs) { int try,retval=0; struct linux_binfmt *fmt; #ifdef __alpha__ /* handle /sbin/loader.. */ { struct exec * eh = (struct exec *) bprm->buf; if (!bprm->loader && eh->fh.f_magic == 0x183 && (eh->fh.f_flags & 0x3000) == 0x3000) { char * dynloader[] = { "/sbin/loader" }; struct file * file; unsigned long loader; allow_write_access(bprm->file); fput(bprm->file); bprm->file = NULL; loader = PAGE_SIZE*MAX_ARG_PAGES-sizeof(void *); file = open_exec(dynloader[0]); retval = PTR_ERR(file); if (IS_ERR(file)) return retval; bprm->file = file; bprm->loader = loader; retval = prepare_binprm(bprm); if (retval<0) return retval; /* should call search_binary_handler recursively here, but it does not matter */ } } #endif 786 for (try=0; try<2; try++) { read_lock(&binfmt_lock); 788 for (fmt = formats ; fmt ; fmt = fmt->next) { int (*fn)(struct linux_binprm *, struct pt_regs *) = fmt->load_binary; 790 if (!fn) 791 continue; 792 if (!try_inc_mod_count(fmt->module)) 793 continue; 794 read_unlock(&binfmt_lock); retval = fn(bprm, regs); 796 if (retval >= 0) { put_binfmt(fmt); allow_write_access(bprm->file); 799 if (bprm->file) fput(bprm->file); bprm->file = NULL; current->did_exec = 1; 803 return retval; } read_lock(&binfmt_lock); put_binfmt(fmt); 807 if (retval != -ENOEXEC) 808 break; 809 if (!bprm->file) { 810 read_unlock(&binfmt_lock); 811 return retval; } } 814 read_unlock(&binfmt_lock); 815 if (retval != -ENOEXEC) { 816 break; #ifdef CONFIG_KMOD }else{ #define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e)) char modname[20]; if (printable(bprm->buf[0]) && printable(bprm->buf[1]) && printable(bprm->buf[2]) && printable(bprm->buf[3])) break; /* -ENOEXEC */ sprintf(modname, "binfmt-%04x", *(unsigned short *)(&bprm->buf[2])); request_module(modname); #endif } } 831 return retval; } /* * sys_execve() executes a new program. */ 838 int do_execve(char * filename, char ** argv, char ** envp, struct pt_regs * regs) { struct linux_binprm bprm; struct file *file; int retval; int i; file = open_exec(filename); retval = PTR_ERR(file); 848 if (IS_ERR(file)) 849 return retval; bprm.p = PAGE_SIZE*MAX_ARG_PAGES-sizeof(void *); memset(bprm.page, 0, MAX_ARG_PAGES*sizeof(bprm.page[0])); bprm.file = file; bprm.filename = filename; bprm.sh_bang = 0; bprm.loader = 0; bprm.exec = 0; 859 if ((bprm.argc = count(argv, bprm.p / sizeof(void *))) < 0) { allow_write_access(file); fput(file); 862 return bprm.argc; } 865 if ((bprm.envc = count(envp, bprm.p / sizeof(void *))) < 0) { allow_write_access(file); fput(file); 868 return bprm.envc; } retval = prepare_binprm(&bprm); 872 if (retval < 0) 873 goto out; retval = copy_strings_kernel(1, &bprm.filename, &bprm); 876 if (retval < 0) 877 goto out; bprm.exec = bprm.p; retval = copy_strings(bprm.envc, envp, &bprm); 881 if (retval < 0) 882 goto out; retval = copy_strings(bprm.argc, argv, &bprm); 885 if (retval < 0) 886 goto out; retval = search_binary_handler(&bprm,regs); 889 if (retval >= 0) /* execve success */ 891 return retval; out: /* Something went wrong, return the inode and free the argument pages*/ allow_write_access(bprm.file); 896 if (bprm.file) fput(bprm.file); 899 for (i = 0 ; i < MAX_ARG_PAGES ; i++) { struct page * page = bprm.page[i]; 901 if (page) __free_page(page); } 905 return retval; } 908 void set_binfmt(struct linux_binfmt *new) { struct linux_binfmt *old = current->binfmt; 911 if (new && new->module) __MOD_INC_USE_COUNT(new->module); current->binfmt = new; 914 if (old && old->module) __MOD_DEC_USE_COUNT(old->module); } 918 int do_coredump(long signr, struct pt_regs * regs) { struct linux_binfmt * binfmt; char corename[6+sizeof(current->comm)]; struct file * file; struct inode * inode; 925 lock_kernel(); binfmt = current->binfmt; 927 if (!binfmt || !binfmt->core_dump) 928 goto fail; 929 if (!current->dumpable || atomic_read(¤t->mm->mm_users) != 1) 930 goto fail; current->dumpable = 0; 932 if (current->rlim[RLIMIT_CORE].rlim_cur < binfmt->min_coredump) 933 goto fail; memcpy(corename,"core.", 5); #if 0 memcpy(corename+5,current->comm,sizeof(current->comm)); #else corename[4] = '\0'; #endif file = filp_open(corename, O_CREAT | 2 | O_TRUNC | O_NOFOLLOW, 0600); 942 if (IS_ERR(file)) 943 goto fail; inode = file->f_dentry->d_inode; 945 if (inode->i_nlink > 1) 946 goto close_fail; /* multiple links - don't dump */ 948 if (!S_ISREG(inode->i_mode)) 949 goto close_fail; 950 if (!file->f_op) 951 goto close_fail; 952 if (!file->f_op->write) 953 goto close_fail; 954 if (!binfmt->core_dump(signr, regs, file)) 955 goto close_fail; 956 unlock_kernel(); filp_close(file, NULL); 958 return 1; close_fail: filp_close(file, NULL); fail: 963 unlock_kernel(); 964 return 0; }