blob: 7302b75a9820fa5c6342e098bb8757c31d884a4e [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/exec.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7/*
8 * #!-checking implemented by tytso.
9 */
10/*
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.
14 *
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.
17 *
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
22 * formats.
23 */
24
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <linux/slab.h>
26#include <linux/file.h>
Al Viro9f3acc32008-04-24 07:44:08 -040027#include <linux/fdtable.h>
Hugh Dickinsba92a432008-07-25 01:45:43 -070028#include <linux/mm.h>
Davidlohr Bueso615d6e82014-04-07 15:37:25 -070029#include <linux/vmacache.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <linux/stat.h>
31#include <linux/fcntl.h>
Hugh Dickinsba92a432008-07-25 01:45:43 -070032#include <linux/swap.h>
Neil Horman74aadce2007-10-16 23:26:35 -070033#include <linux/string.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/init.h>
Hugh Dickinsca5b1722008-07-28 15:46:18 -070035#include <linux/pagemap.h>
Ingo Molnarcdd6c482009-09-21 12:02:48 +020036#include <linux/perf_event.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include <linux/highmem.h>
38#include <linux/spinlock.h>
39#include <linux/key.h>
40#include <linux/personality.h>
41#include <linux/binfmts.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <linux/utsname.h>
Sukadev Bhattiprolu84d73782006-12-08 02:38:01 -080043#include <linux/pid_namespace.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#include <linux/module.h>
45#include <linux/namei.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070046#include <linux/mount.h>
47#include <linux/security.h>
48#include <linux/syscalls.h>
Jay Lan8f0ab512006-09-30 23:28:59 -070049#include <linux/tsacct_kern.h>
Matt Helsley9f460802005-11-07 00:59:16 -080050#include <linux/cn_proc.h>
Al Viro473ae302006-04-26 14:04:08 -040051#include <linux/audit.h>
Roland McGrath6341c392008-07-25 19:45:44 -070052#include <linux/tracehook.h>
Johannes Berg5f4123b2008-07-09 10:28:40 +020053#include <linux/kmod.h>
Eric Paris6110e3a2008-12-17 13:53:20 -050054#include <linux/fsnotify.h>
Al Viro5ad4e532009-03-29 19:50:06 -040055#include <linux/fs_struct.h>
Neil Horman61be2282009-09-23 15:56:58 -070056#include <linux/pipe_fs_i.h>
Ying Han3d5992d2010-10-26 14:21:23 -070057#include <linux/oom.h>
Oleg Nesterov0e028462011-03-06 18:02:54 +010058#include <linux/compat.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070059
60#include <asm/uaccess.h>
61#include <asm/mmu_context.h>
Ollie Wildb6a2fea2007-07-19 01:48:16 -070062#include <asm/tlb.h>
KAMEZAWA Hiroyuki43d2b112012-01-10 15:08:09 -080063
64#include <trace/events/task.h>
David Howellsa6f76f22008-11-14 10:39:24 +110065#include "internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
David Smith4ff16c22012-02-07 10:11:05 -060067#include <trace/events/sched.h>
68
Alan Coxd6e71142005-06-23 00:09:43 -070069int suid_dumpable = 0;
70
Alexey Dobriyane4dc1b12007-10-16 23:26:03 -070071static LIST_HEAD(formats);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072static DEFINE_RWLOCK(binfmt_lock);
73
Al Viro8fc3dc52012-03-17 03:05:16 -040074void __register_binfmt(struct linux_binfmt * fmt, int insert)
Linus Torvalds1da177e2005-04-16 15:20:36 -070075{
Al Viro8fc3dc52012-03-17 03:05:16 -040076 BUG_ON(!fmt);
Oleg Nesterov92eaa562013-09-11 14:24:42 -070077 if (WARN_ON(!fmt->load_binary))
78 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 write_lock(&binfmt_lock);
Ivan Kokshaysky74641f52009-04-30 15:08:49 -070080 insert ? list_add(&fmt->lh, &formats) :
81 list_add_tail(&fmt->lh, &formats);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 write_unlock(&binfmt_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070083}
84
Ivan Kokshaysky74641f52009-04-30 15:08:49 -070085EXPORT_SYMBOL(__register_binfmt);
Linus Torvalds1da177e2005-04-16 15:20:36 -070086
Alexey Dobriyanf6b450d2007-10-16 23:26:04 -070087void unregister_binfmt(struct linux_binfmt * fmt)
Linus Torvalds1da177e2005-04-16 15:20:36 -070088{
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 write_lock(&binfmt_lock);
Alexey Dobriyane4dc1b12007-10-16 23:26:03 -070090 list_del(&fmt->lh);
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 write_unlock(&binfmt_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070092}
93
94EXPORT_SYMBOL(unregister_binfmt);
95
96static inline void put_binfmt(struct linux_binfmt * fmt)
97{
98 module_put(fmt->module);
99}
100
Josh Triplett69369a72014-04-03 14:48:27 -0700101#ifdef CONFIG_USELIB
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102/*
103 * Note that a shared library must be both readable and executable due to
104 * security reasons.
105 *
106 * Also note that we take the address to load from from the file itself.
107 */
Heiko Carstens1e7bfb22009-01-14 14:14:29 +0100108SYSCALL_DEFINE1(uselib, const char __user *, library)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109{
Al Viro72c2d532013-09-22 16:27:52 -0400110 struct linux_binfmt *fmt;
Al Viro964bd182008-07-26 03:33:14 -0400111 struct file *file;
Jeff Layton91a27b22012-10-10 15:25:28 -0400112 struct filename *tmp = getname(library);
Al Viro964bd182008-07-26 03:33:14 -0400113 int error = PTR_ERR(tmp);
Al Viro47c805d2011-02-23 17:44:09 -0500114 static const struct open_flags uselib_flags = {
115 .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC,
116 .acc_mode = MAY_READ | MAY_EXEC | MAY_OPEN,
Al Virof9652e12013-06-11 08:23:01 +0400117 .intent = LOOKUP_OPEN,
118 .lookup_flags = LOOKUP_FOLLOW,
Al Viro47c805d2011-02-23 17:44:09 -0500119 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
Al Viro6e8341a2009-04-06 11:16:22 -0400121 if (IS_ERR(tmp))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 goto out;
123
Al Virof9652e12013-06-11 08:23:01 +0400124 file = do_filp_open(AT_FDCWD, tmp, &uselib_flags);
Al Viro6e8341a2009-04-06 11:16:22 -0400125 putname(tmp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126 error = PTR_ERR(file);
127 if (IS_ERR(file))
128 goto out;
129
Al Viro6e8341a2009-04-06 11:16:22 -0400130 error = -EINVAL;
Al Viro496ad9a2013-01-23 17:07:38 -0500131 if (!S_ISREG(file_inode(file)->i_mode))
Al Viro6e8341a2009-04-06 11:16:22 -0400132 goto exit;
133
134 error = -EACCES;
135 if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
136 goto exit;
137
Eric Paris2a12a9d2009-12-17 21:24:21 -0500138 fsnotify_open(file);
Eric Paris6110e3a2008-12-17 13:53:20 -0500139
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 error = -ENOEXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141
Al Viro72c2d532013-09-22 16:27:52 -0400142 read_lock(&binfmt_lock);
143 list_for_each_entry(fmt, &formats, lh) {
144 if (!fmt->load_shlib)
145 continue;
146 if (!try_module_get(fmt->module))
147 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 read_unlock(&binfmt_lock);
Al Viro72c2d532013-09-22 16:27:52 -0400149 error = fmt->load_shlib(file);
150 read_lock(&binfmt_lock);
151 put_binfmt(fmt);
152 if (error != -ENOEXEC)
153 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 }
Al Viro72c2d532013-09-22 16:27:52 -0400155 read_unlock(&binfmt_lock);
Al Viro6e8341a2009-04-06 11:16:22 -0400156exit:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 fput(file);
158out:
159 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160}
Josh Triplett69369a72014-04-03 14:48:27 -0700161#endif /* #ifdef CONFIG_USELIB */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700163#ifdef CONFIG_MMU
Oleg Nesterovae6b5852011-03-06 18:03:11 +0100164/*
165 * The nascent bprm->mm is not visible until exec_mmap() but it can
166 * use a lot of memory, account these pages in current->mm temporary
167 * for oom_badness()->get_mm_rss(). Once exec succeeds or fails, we
168 * change the counter back via acct_arg_size(0).
169 */
Oleg Nesterov0e028462011-03-06 18:02:54 +0100170static void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)
Oleg Nesterov3c77f842010-11-30 20:55:34 +0100171{
172 struct mm_struct *mm = current->mm;
173 long diff = (long)(pages - bprm->vma_pages);
174
175 if (!mm || !diff)
176 return;
177
178 bprm->vma_pages = pages;
Oleg Nesterov3c77f842010-11-30 20:55:34 +0100179 add_mm_counter(mm, MM_ANONPAGES, diff);
Oleg Nesterov3c77f842010-11-30 20:55:34 +0100180}
181
Oleg Nesterov0e028462011-03-06 18:02:54 +0100182static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700183 int write)
184{
185 struct page *page;
186 int ret;
187
188#ifdef CONFIG_STACK_GROWSUP
189 if (write) {
Michal Hockod05f3162011-05-24 17:11:44 -0700190 ret = expand_downwards(bprm->vma, pos);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700191 if (ret < 0)
192 return NULL;
193 }
194#endif
195 ret = get_user_pages(current, bprm->mm, pos,
196 1, write, 1, &page, NULL);
197 if (ret <= 0)
198 return NULL;
199
200 if (write) {
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700201 unsigned long size = bprm->vma->vm_end - bprm->vma->vm_start;
Linus Torvaldsa64e7152008-03-03 10:12:14 -0800202 struct rlimit *rlim;
203
Oleg Nesterov3c77f842010-11-30 20:55:34 +0100204 acct_arg_size(bprm, size / PAGE_SIZE);
205
Linus Torvaldsa64e7152008-03-03 10:12:14 -0800206 /*
207 * We've historically supported up to 32 pages (ARG_MAX)
208 * of argument strings even with small stacks
209 */
210 if (size <= ARG_MAX)
211 return page;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700212
213 /*
214 * Limit to 1/4-th the stack size for the argv+env strings.
215 * This ensures that:
216 * - the remaining binfmt code will not run out of stack space,
217 * - the program will have a reasonable amount of stack left
218 * to work from.
219 */
Linus Torvaldsa64e7152008-03-03 10:12:14 -0800220 rlim = current->signal->rlim;
Jiri Slabyd554ed892010-03-05 13:42:42 -0800221 if (size > ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur) / 4) {
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700222 put_page(page);
223 return NULL;
224 }
225 }
226
227 return page;
228}
229
230static void put_arg_page(struct page *page)
231{
232 put_page(page);
233}
234
235static void free_arg_page(struct linux_binprm *bprm, int i)
236{
237}
238
239static void free_arg_pages(struct linux_binprm *bprm)
240{
241}
242
243static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,
244 struct page *page)
245{
246 flush_cache_page(bprm->vma, pos, page_to_pfn(page));
247}
248
249static int __bprm_mm_init(struct linux_binprm *bprm)
250{
Luiz Fernando N. Capitulinoeaccbfa2009-01-06 14:40:44 -0800251 int err;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700252 struct vm_area_struct *vma = NULL;
253 struct mm_struct *mm = bprm->mm;
254
255 bprm->vma = vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
256 if (!vma)
Luiz Fernando N. Capitulinoeaccbfa2009-01-06 14:40:44 -0800257 return -ENOMEM;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700258
259 down_write(&mm->mmap_sem);
260 vma->vm_mm = mm;
261
262 /*
263 * Place the stack at the largest stack address the architecture
264 * supports. Later, we'll move this to an appropriate place. We don't
265 * use STACK_TOP because that can depend on attributes which aren't
266 * configured yet.
267 */
Michal Hockoaacb3d12011-07-26 16:08:40 -0700268 BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700269 vma->vm_end = STACK_TOP_MAX;
270 vma->vm_start = vma->vm_end - PAGE_SIZE;
Cyrill Gorcunovd9104d12013-09-11 14:22:24 -0700271 vma->vm_flags = VM_SOFTDIRTY | VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP;
Coly Li3ed75eb2007-10-18 23:39:15 -0700272 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
Rik van Riel5beb4932010-03-05 13:42:07 -0800273 INIT_LIST_HEAD(&vma->anon_vma_chain);
Tavis Ormandy462e635e2010-12-09 15:29:42 +0100274
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700275 err = insert_vm_struct(mm, vma);
Luiz Fernando N. Capitulinoeaccbfa2009-01-06 14:40:44 -0800276 if (err)
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700277 goto err;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700278
279 mm->stack_vm = mm->total_vm = 1;
280 up_write(&mm->mmap_sem);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700281 bprm->p = vma->vm_end - sizeof(void *);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700282 return 0;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700283err:
Luiz Fernando N. Capitulinoeaccbfa2009-01-06 14:40:44 -0800284 up_write(&mm->mmap_sem);
285 bprm->vma = NULL;
286 kmem_cache_free(vm_area_cachep, vma);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700287 return err;
288}
289
290static bool valid_arg_len(struct linux_binprm *bprm, long len)
291{
292 return len <= MAX_ARG_STRLEN;
293}
294
295#else
296
Oleg Nesterov0e028462011-03-06 18:02:54 +0100297static inline void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)
Oleg Nesterov3c77f842010-11-30 20:55:34 +0100298{
299}
300
Oleg Nesterov0e028462011-03-06 18:02:54 +0100301static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700302 int write)
303{
304 struct page *page;
305
306 page = bprm->page[pos / PAGE_SIZE];
307 if (!page && write) {
308 page = alloc_page(GFP_HIGHUSER|__GFP_ZERO);
309 if (!page)
310 return NULL;
311 bprm->page[pos / PAGE_SIZE] = page;
312 }
313
314 return page;
315}
316
317static void put_arg_page(struct page *page)
318{
319}
320
321static void free_arg_page(struct linux_binprm *bprm, int i)
322{
323 if (bprm->page[i]) {
324 __free_page(bprm->page[i]);
325 bprm->page[i] = NULL;
326 }
327}
328
329static void free_arg_pages(struct linux_binprm *bprm)
330{
331 int i;
332
333 for (i = 0; i < MAX_ARG_PAGES; i++)
334 free_arg_page(bprm, i);
335}
336
337static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,
338 struct page *page)
339{
340}
341
342static int __bprm_mm_init(struct linux_binprm *bprm)
343{
344 bprm->p = PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *);
345 return 0;
346}
347
348static bool valid_arg_len(struct linux_binprm *bprm, long len)
349{
350 return len <= bprm->p;
351}
352
353#endif /* CONFIG_MMU */
354
355/*
356 * Create a new mm_struct and populate it with a temporary stack
357 * vm_area_struct. We don't have enough context at this point to set the stack
358 * flags, permissions, and offset, so we use temporary values. We'll update
359 * them later in setup_arg_pages().
360 */
Yuanhan Liu9cc64ce2013-02-20 13:16:01 +1100361static int bprm_mm_init(struct linux_binprm *bprm)
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700362{
363 int err;
364 struct mm_struct *mm = NULL;
365
366 bprm->mm = mm = mm_alloc();
367 err = -ENOMEM;
368 if (!mm)
369 goto err;
370
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700371 err = __bprm_mm_init(bprm);
372 if (err)
373 goto err;
374
375 return 0;
376
377err:
378 if (mm) {
379 bprm->mm = NULL;
380 mmdrop(mm);
381 }
382
383 return err;
384}
385
Oleg Nesterovba2d01622011-03-06 18:02:37 +0100386struct user_arg_ptr {
Oleg Nesterov0e028462011-03-06 18:02:54 +0100387#ifdef CONFIG_COMPAT
388 bool is_compat;
389#endif
390 union {
391 const char __user *const __user *native;
392#ifdef CONFIG_COMPAT
Al Viro38b983b2012-09-30 13:38:55 -0400393 const compat_uptr_t __user *compat;
Oleg Nesterov0e028462011-03-06 18:02:54 +0100394#endif
395 } ptr;
Oleg Nesterovba2d01622011-03-06 18:02:37 +0100396};
397
398static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr)
Oleg Nesterov1d1dbf82011-03-06 18:02:21 +0100399{
Oleg Nesterov0e028462011-03-06 18:02:54 +0100400 const char __user *native;
Oleg Nesterov1d1dbf82011-03-06 18:02:21 +0100401
Oleg Nesterov0e028462011-03-06 18:02:54 +0100402#ifdef CONFIG_COMPAT
403 if (unlikely(argv.is_compat)) {
404 compat_uptr_t compat;
405
406 if (get_user(compat, argv.ptr.compat + nr))
407 return ERR_PTR(-EFAULT);
408
409 return compat_ptr(compat);
410 }
411#endif
412
413 if (get_user(native, argv.ptr.native + nr))
Oleg Nesterov1d1dbf82011-03-06 18:02:21 +0100414 return ERR_PTR(-EFAULT);
415
Oleg Nesterov0e028462011-03-06 18:02:54 +0100416 return native;
Oleg Nesterov1d1dbf82011-03-06 18:02:21 +0100417}
418
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419/*
420 * count() counts the number of strings in array ARGV.
421 */
Oleg Nesterovba2d01622011-03-06 18:02:37 +0100422static int count(struct user_arg_ptr argv, int max)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423{
424 int i = 0;
425
Oleg Nesterov0e028462011-03-06 18:02:54 +0100426 if (argv.ptr.native != NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427 for (;;) {
Oleg Nesterov1d1dbf82011-03-06 18:02:21 +0100428 const char __user *p = get_user_arg_ptr(argv, i);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 if (!p)
431 break;
Oleg Nesterov1d1dbf82011-03-06 18:02:21 +0100432
433 if (IS_ERR(p))
434 return -EFAULT;
435
Xi Wang6d92d4f2013-01-11 14:31:48 -0800436 if (i >= max)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437 return -E2BIG;
Xi Wang6d92d4f2013-01-11 14:31:48 -0800438 ++i;
Roland McGrath9aea5a62010-09-07 19:37:06 -0700439
440 if (fatal_signal_pending(current))
441 return -ERESTARTNOHAND;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 cond_resched();
443 }
444 }
445 return i;
446}
447
448/*
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700449 * 'copy_strings()' copies argument/environment strings from the old
450 * processes's memory to the new process's stack. The call to get_user_pages()
451 * ensures the destination page is created and not swapped out.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 */
Oleg Nesterovba2d01622011-03-06 18:02:37 +0100453static int copy_strings(int argc, struct user_arg_ptr argv,
Adrian Bunk75c96f82005-05-05 16:16:09 -0700454 struct linux_binprm *bprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455{
456 struct page *kmapped_page = NULL;
457 char *kaddr = NULL;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700458 unsigned long kpos = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 int ret;
460
461 while (argc-- > 0) {
David Howellsd7627462010-08-17 23:52:56 +0100462 const char __user *str;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 int len;
464 unsigned long pos;
465
Oleg Nesterov1d1dbf82011-03-06 18:02:21 +0100466 ret = -EFAULT;
467 str = get_user_arg_ptr(argv, argc);
468 if (IS_ERR(str))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470
Oleg Nesterov1d1dbf82011-03-06 18:02:21 +0100471 len = strnlen_user(str, MAX_ARG_STRLEN);
472 if (!len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 goto out;
Oleg Nesterov1d1dbf82011-03-06 18:02:21 +0100474
475 ret = -E2BIG;
476 if (!valid_arg_len(bprm, len))
477 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700479 /* We're going to work our way backwords. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480 pos = bprm->p;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700481 str += len;
482 bprm->p -= len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483
484 while (len > 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485 int offset, bytes_to_copy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486
Roland McGrath9aea5a62010-09-07 19:37:06 -0700487 if (fatal_signal_pending(current)) {
488 ret = -ERESTARTNOHAND;
489 goto out;
490 }
Roland McGrath7993bc12010-09-07 19:36:28 -0700491 cond_resched();
492
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493 offset = pos % PAGE_SIZE;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700494 if (offset == 0)
495 offset = PAGE_SIZE;
496
497 bytes_to_copy = offset;
498 if (bytes_to_copy > len)
499 bytes_to_copy = len;
500
501 offset -= bytes_to_copy;
502 pos -= bytes_to_copy;
503 str -= bytes_to_copy;
504 len -= bytes_to_copy;
505
506 if (!kmapped_page || kpos != (pos & PAGE_MASK)) {
507 struct page *page;
508
509 page = get_arg_page(bprm, pos, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 if (!page) {
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700511 ret = -E2BIG;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 goto out;
513 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700515 if (kmapped_page) {
516 flush_kernel_dcache_page(kmapped_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517 kunmap(kmapped_page);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700518 put_arg_page(kmapped_page);
519 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 kmapped_page = page;
521 kaddr = kmap(kmapped_page);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700522 kpos = pos & PAGE_MASK;
523 flush_arg_page(bprm, kpos, kmapped_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 }
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700525 if (copy_from_user(kaddr+offset, str, bytes_to_copy)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 ret = -EFAULT;
527 goto out;
528 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529 }
530 }
531 ret = 0;
532out:
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700533 if (kmapped_page) {
534 flush_kernel_dcache_page(kmapped_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 kunmap(kmapped_page);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700536 put_arg_page(kmapped_page);
537 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 return ret;
539}
540
541/*
542 * Like copy_strings, but get argv and its values from kernel memory.
543 */
Oleg Nesterovba2d01622011-03-06 18:02:37 +0100544int copy_strings_kernel(int argc, const char *const *__argv,
David Howellsd7627462010-08-17 23:52:56 +0100545 struct linux_binprm *bprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546{
547 int r;
548 mm_segment_t oldfs = get_fs();
Oleg Nesterovba2d01622011-03-06 18:02:37 +0100549 struct user_arg_ptr argv = {
Oleg Nesterov0e028462011-03-06 18:02:54 +0100550 .ptr.native = (const char __user *const __user *)__argv,
Oleg Nesterovba2d01622011-03-06 18:02:37 +0100551 };
552
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 set_fs(KERNEL_DS);
Oleg Nesterovba2d01622011-03-06 18:02:37 +0100554 r = copy_strings(argc, argv, bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 set_fs(oldfs);
Oleg Nesterovba2d01622011-03-06 18:02:37 +0100556
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 return r;
558}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559EXPORT_SYMBOL(copy_strings_kernel);
560
561#ifdef CONFIG_MMU
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700562
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563/*
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700564 * During bprm_mm_init(), we create a temporary stack at STACK_TOP_MAX. Once
565 * the binfmt code determines where the new stack should reside, we shift it to
566 * its final location. The process proceeds as follows:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 *
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700568 * 1) Use shift to calculate the new vma endpoints.
569 * 2) Extend vma to cover both the old and new ranges. This ensures the
570 * arguments passed to subsequent functions are consistent.
571 * 3) Move vma's page tables to the new range.
572 * 4) Free up any cleared pgd range.
573 * 5) Shrink the vma to cover only the new range.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 */
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700575static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576{
577 struct mm_struct *mm = vma->vm_mm;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700578 unsigned long old_start = vma->vm_start;
579 unsigned long old_end = vma->vm_end;
580 unsigned long length = old_end - old_start;
581 unsigned long new_start = old_start - shift;
582 unsigned long new_end = old_end - shift;
Peter Zijlstrad16dfc52011-05-24 17:11:45 -0700583 struct mmu_gather tlb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700585 BUG_ON(new_start > new_end);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700587 /*
588 * ensure there are no vmas between where we want to go
589 * and where we are
590 */
591 if (vma != find_vma(mm, new_start))
592 return -EFAULT;
593
594 /*
595 * cover the whole range: [new_start, old_end)
596 */
Rik van Riel5beb4932010-03-05 13:42:07 -0800597 if (vma_adjust(vma, new_start, old_end, vma->vm_pgoff, NULL))
598 return -ENOMEM;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700599
600 /*
601 * move the page tables downwards, on failure we rely on
602 * process cleanup to remove whatever mess we made.
603 */
604 if (length != move_page_tables(vma, old_start,
Michel Lespinasse38a76012012-10-08 16:31:50 -0700605 vma, new_start, length, false))
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700606 return -ENOMEM;
607
608 lru_add_drain();
Linus Torvalds2b047252013-08-15 11:42:25 -0700609 tlb_gather_mmu(&tlb, mm, old_start, old_end);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700610 if (new_end > old_start) {
611 /*
612 * when the old and new regions overlap clear from new_end.
613 */
Peter Zijlstrad16dfc52011-05-24 17:11:45 -0700614 free_pgd_range(&tlb, new_end, old_end, new_end,
Hugh Dickins6ee86302013-04-29 15:07:44 -0700615 vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING);
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700616 } else {
617 /*
618 * otherwise, clean from old_start; this is done to not touch
619 * the address space in [new_end, old_start) some architectures
620 * have constraints on va-space that make this illegal (IA64) -
621 * for the others its just a little faster.
622 */
Peter Zijlstrad16dfc52011-05-24 17:11:45 -0700623 free_pgd_range(&tlb, old_start, old_end, new_end,
Hugh Dickins6ee86302013-04-29 15:07:44 -0700624 vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 }
Linus Torvalds2b047252013-08-15 11:42:25 -0700626 tlb_finish_mmu(&tlb, old_start, old_end);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700628 /*
Rik van Riel5beb4932010-03-05 13:42:07 -0800629 * Shrink the vma to just the new range. Always succeeds.
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700630 */
631 vma_adjust(vma, new_start, new_end, vma->vm_pgoff, NULL);
632
633 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634}
635
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700636/*
637 * Finalizes the stack vm_area_struct. The flags and permissions are updated,
638 * the stack is optionally relocated, and some extra space is added.
639 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640int setup_arg_pages(struct linux_binprm *bprm,
641 unsigned long stack_top,
642 int executable_stack)
643{
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700644 unsigned long ret;
645 unsigned long stack_shift;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 struct mm_struct *mm = current->mm;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700647 struct vm_area_struct *vma = bprm->vma;
648 struct vm_area_struct *prev = NULL;
649 unsigned long vm_flags;
650 unsigned long stack_base;
Michael Neuling803bf5e2010-02-10 13:56:42 -0800651 unsigned long stack_size;
652 unsigned long stack_expand;
653 unsigned long rlim_stack;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654
655#ifdef CONFIG_STACK_GROWSUP
James Hogand71f2902014-05-13 23:58:24 +0100656 /* Limit stack size */
Jiri Slabyd554ed892010-03-05 13:42:42 -0800657 stack_base = rlimit_max(RLIMIT_STACK);
James Hogand71f2902014-05-13 23:58:24 +0100658 if (stack_base > STACK_SIZE_MAX)
659 stack_base = STACK_SIZE_MAX;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700661 /* Make sure we didn't let the argument array grow too large. */
662 if (vma->vm_end - vma->vm_start > stack_base)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 return -ENOMEM;
664
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700665 stack_base = PAGE_ALIGN(stack_top - stack_base);
666
667 stack_shift = vma->vm_start - stack_base;
668 mm->arg_start = bprm->p - stack_shift;
669 bprm->p = vma->vm_end - stack_shift;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670#else
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700671 stack_top = arch_align_stack(stack_top);
672 stack_top = PAGE_ALIGN(stack_top);
Roland McGrath1b528182010-09-07 19:35:49 -0700673
674 if (unlikely(stack_top < mmap_min_addr) ||
675 unlikely(vma->vm_end - vma->vm_start >= stack_top - mmap_min_addr))
676 return -ENOMEM;
677
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700678 stack_shift = vma->vm_end - stack_top;
679
680 bprm->p -= stack_shift;
681 mm->arg_start = bprm->p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682#endif
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700683
684 if (bprm->loader)
685 bprm->loader -= stack_shift;
686 bprm->exec -= stack_shift;
687
688 down_write(&mm->mmap_sem);
Hugh Dickins96a8e132008-07-10 21:19:20 +0100689 vm_flags = VM_STACK_FLAGS;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700690
691 /*
692 * Adjust stack execute permissions; explicitly enable for
693 * EXSTACK_ENABLE_X, disable for EXSTACK_DISABLE_X and leave alone
694 * (arch default) otherwise.
695 */
696 if (unlikely(executable_stack == EXSTACK_ENABLE_X))
697 vm_flags |= VM_EXEC;
698 else if (executable_stack == EXSTACK_DISABLE_X)
699 vm_flags &= ~VM_EXEC;
700 vm_flags |= mm->def_flags;
Mel Gormana8bef8ff2010-05-24 14:32:24 -0700701 vm_flags |= VM_STACK_INCOMPLETE_SETUP;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700702
703 ret = mprotect_fixup(vma, &prev, vma->vm_start, vma->vm_end,
704 vm_flags);
705 if (ret)
706 goto out_unlock;
707 BUG_ON(prev != vma);
708
709 /* Move stack pages down in memory. */
710 if (stack_shift) {
711 ret = shift_arg_pages(vma, stack_shift);
Anton Blanchardfc63cf22009-11-11 14:26:48 -0800712 if (ret)
713 goto out_unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714 }
715
Mel Gormana8bef8ff2010-05-24 14:32:24 -0700716 /* mprotect_fixup is overkill to remove the temporary stack flags */
717 vma->vm_flags &= ~VM_STACK_INCOMPLETE_SETUP;
718
Michael Neuling5ef097d2010-03-05 13:42:57 -0800719 stack_expand = 131072UL; /* randomly 32*4k (or 2*64k) pages */
Michael Neuling803bf5e2010-02-10 13:56:42 -0800720 stack_size = vma->vm_end - vma->vm_start;
721 /*
722 * Align this down to a page boundary as expand_stack
723 * will align it up.
724 */
725 rlim_stack = rlimit(RLIMIT_STACK) & PAGE_MASK;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700726#ifdef CONFIG_STACK_GROWSUP
Michael Neuling803bf5e2010-02-10 13:56:42 -0800727 if (stack_size + stack_expand > rlim_stack)
728 stack_base = vma->vm_start + rlim_stack;
729 else
730 stack_base = vma->vm_end + stack_expand;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700731#else
Michael Neuling803bf5e2010-02-10 13:56:42 -0800732 if (stack_size + stack_expand > rlim_stack)
733 stack_base = vma->vm_end - rlim_stack;
734 else
735 stack_base = vma->vm_start - stack_expand;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700736#endif
Eric B Munson3af9e852010-05-18 15:30:49 +0100737 current->mm->start_stack = bprm->p;
Ollie Wildb6a2fea2007-07-19 01:48:16 -0700738 ret = expand_stack(vma, stack_base);
739 if (ret)
740 ret = -EFAULT;
741
742out_unlock:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 up_write(&mm->mmap_sem);
Anton Blanchardfc63cf22009-11-11 14:26:48 -0800744 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746EXPORT_SYMBOL(setup_arg_pages);
747
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748#endif /* CONFIG_MMU */
749
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -0800750static struct file *do_open_exec(struct filename *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 struct file *file;
Christoph Hellwige56b6a52008-05-19 07:53:34 +0200753 int err;
Al Viro47c805d2011-02-23 17:44:09 -0500754 static const struct open_flags open_exec_flags = {
755 .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC,
756 .acc_mode = MAY_EXEC | MAY_OPEN,
Al Virof9652e12013-06-11 08:23:01 +0400757 .intent = LOOKUP_OPEN,
758 .lookup_flags = LOOKUP_FOLLOW,
Al Viro47c805d2011-02-23 17:44:09 -0500759 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700760
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -0800761 file = do_filp_open(AT_FDCWD, name, &open_exec_flags);
Al Viro6e8341a2009-04-06 11:16:22 -0400762 if (IS_ERR(file))
Christoph Hellwige56b6a52008-05-19 07:53:34 +0200763 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764
Christoph Hellwige56b6a52008-05-19 07:53:34 +0200765 err = -EACCES;
Al Viro496ad9a2013-01-23 17:07:38 -0500766 if (!S_ISREG(file_inode(file)->i_mode))
Al Viro6e8341a2009-04-06 11:16:22 -0400767 goto exit;
Christoph Hellwige56b6a52008-05-19 07:53:34 +0200768
Al Viro6e8341a2009-04-06 11:16:22 -0400769 if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
770 goto exit;
Christoph Hellwige56b6a52008-05-19 07:53:34 +0200771
Eric Paris2a12a9d2009-12-17 21:24:21 -0500772 fsnotify_open(file);
Eric Paris6110e3a2008-12-17 13:53:20 -0500773
Christoph Hellwige56b6a52008-05-19 07:53:34 +0200774 err = deny_write_access(file);
Al Viro6e8341a2009-04-06 11:16:22 -0400775 if (err)
776 goto exit;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777
Al Viro6e8341a2009-04-06 11:16:22 -0400778out:
Christoph Hellwige56b6a52008-05-19 07:53:34 +0200779 return file;
780
Al Viro6e8341a2009-04-06 11:16:22 -0400781exit:
782 fput(file);
Christoph Hellwige56b6a52008-05-19 07:53:34 +0200783 return ERR_PTR(err);
784}
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -0800785
786struct file *open_exec(const char *name)
787{
788 struct filename tmp = { .name = name };
789 return do_open_exec(&tmp);
790}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791EXPORT_SYMBOL(open_exec);
792
Mimi Zohar6777d772009-08-21 14:32:48 -0400793int kernel_read(struct file *file, loff_t offset,
794 char *addr, unsigned long count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795{
796 mm_segment_t old_fs;
797 loff_t pos = offset;
798 int result;
799
800 old_fs = get_fs();
801 set_fs(get_ds());
802 /* The cast to a user pointer is valid due to the set_fs() */
803 result = vfs_read(file, (void __user *)addr, count, &pos);
804 set_fs(old_fs);
805 return result;
806}
807
808EXPORT_SYMBOL(kernel_read);
809
Al Viro3dc20cb2013-04-13 20:31:37 -0400810ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len)
811{
Al Viroec695572014-02-04 19:08:21 -0500812 ssize_t res = vfs_read(file, (void __user *)addr, len, &pos);
Al Viro3dc20cb2013-04-13 20:31:37 -0400813 if (res > 0)
814 flush_icache_range(addr, addr + len);
815 return res;
816}
817EXPORT_SYMBOL(read_code);
818
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819static int exec_mmap(struct mm_struct *mm)
820{
821 struct task_struct *tsk;
Davidlohr Bueso615d6e82014-04-07 15:37:25 -0700822 struct mm_struct *old_mm, *active_mm;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700823
824 /* Notify parent that we're no longer interested in the old VM */
825 tsk = current;
826 old_mm = current->mm;
827 mm_release(tsk, old_mm);
828
829 if (old_mm) {
Konstantin Khlebnikov4fe7efd2012-06-20 12:53:01 -0700830 sync_mm_rss(old_mm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831 /*
832 * Make sure that if there is a core dump in progress
833 * for the old mm, we get out and die instead of going
834 * through with the exec. We must hold mmap_sem around
Oleg Nesterov999d9fc2008-07-25 01:47:41 -0700835 * checking core_state and changing tsk->mm.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836 */
837 down_read(&old_mm->mmap_sem);
Oleg Nesterov999d9fc2008-07-25 01:47:41 -0700838 if (unlikely(old_mm->core_state)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839 up_read(&old_mm->mmap_sem);
840 return -EINTR;
841 }
842 }
843 task_lock(tsk);
844 active_mm = tsk->active_mm;
845 tsk->mm = mm;
846 tsk->active_mm = mm;
847 activate_mm(active_mm, mm);
Davidlohr Bueso615d6e82014-04-07 15:37:25 -0700848 tsk->mm->vmacache_seqnum = 0;
849 vmacache_flush(tsk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850 task_unlock(tsk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851 if (old_mm) {
852 up_read(&old_mm->mmap_sem);
Eric Sesterhenn7dddb122006-04-01 01:13:38 +0200853 BUG_ON(active_mm != old_mm);
Oleg Nesterov701085b2012-03-19 17:04:01 +0100854 setmax_mm_hiwater_rss(&tsk->signal->maxrss, old_mm);
Balbir Singh31a78f22008-09-28 23:09:31 +0100855 mm_update_next_owner(old_mm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856 mmput(old_mm);
857 return 0;
858 }
859 mmdrop(active_mm);
860 return 0;
861}
862
863/*
864 * This function makes sure the current process has its own signal table,
865 * so that flush_signal_handlers can later reset the handlers without
866 * disturbing other processes. (Other processes might share the signal
867 * table via the CLONE_SIGHAND option to clone().)
868 */
Arjan van de Ven858119e2006-01-14 13:20:43 -0800869static int de_thread(struct task_struct *tsk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870{
871 struct signal_struct *sig = tsk->signal;
Oleg Nesterovb2c903b2007-10-16 23:27:22 -0700872 struct sighand_struct *oldsighand = tsk->sighand;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873 spinlock_t *lock = &oldsighand->siglock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -0700875 if (thread_group_empty(tsk))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876 goto no_thread_group;
877
878 /*
879 * Kill all other threads in the thread group.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700881 spin_lock_irq(lock);
Oleg Nesteroved5d2ca2008-02-04 22:27:24 -0800882 if (signal_group_exit(sig)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883 /*
884 * Another group action in progress, just
885 * return so that the signal is processed.
886 */
887 spin_unlock_irq(lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700888 return -EAGAIN;
889 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890
Oleg Nesterovd3441932010-05-26 14:43:11 -0700891 sig->group_exit_task = tsk;
892 sig->notify_count = zap_other_threads(tsk);
893 if (!thread_group_leader(tsk))
894 sig->notify_count--;
895
896 while (sig->notify_count) {
Oleg Nesterovd5bbd432012-10-08 19:13:01 +0200897 __set_current_state(TASK_KILLABLE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898 spin_unlock_irq(lock);
899 schedule();
Oleg Nesterovd5bbd432012-10-08 19:13:01 +0200900 if (unlikely(__fatal_signal_pending(tsk)))
901 goto killed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902 spin_lock_irq(lock);
903 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904 spin_unlock_irq(lock);
905
906 /*
907 * At this point all other threads have exited, all we have to
908 * do is to wait for the thread group leader to become inactive,
909 * and to assume its PID:
910 */
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -0700911 if (!thread_group_leader(tsk)) {
Oleg Nesterov81879262008-12-01 14:18:16 -0800912 struct task_struct *leader = tsk->group_leader;
Oleg Nesterov6db840f2007-10-16 23:27:23 -0700913
Oleg Nesterov2800d8d2008-04-30 00:53:12 -0700914 sig->notify_count = -1; /* for exit_notify() */
Oleg Nesterov6db840f2007-10-16 23:27:23 -0700915 for (;;) {
Oleg Nesterove56fb282013-04-30 15:28:20 -0700916 threadgroup_change_begin(tsk);
Oleg Nesterov6db840f2007-10-16 23:27:23 -0700917 write_lock_irq(&tasklist_lock);
918 if (likely(leader->exit_state))
919 break;
Oleg Nesterovd5bbd432012-10-08 19:13:01 +0200920 __set_current_state(TASK_KILLABLE);
Oleg Nesterov6db840f2007-10-16 23:27:23 -0700921 write_unlock_irq(&tasklist_lock);
Oleg Nesterove56fb282013-04-30 15:28:20 -0700922 threadgroup_change_end(tsk);
Oleg Nesterov6db840f2007-10-16 23:27:23 -0700923 schedule();
Oleg Nesterovd5bbd432012-10-08 19:13:01 +0200924 if (unlikely(__fatal_signal_pending(tsk)))
925 goto killed;
Oleg Nesterov6db840f2007-10-16 23:27:23 -0700926 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927
Roland McGrathf5e90282006-04-10 22:54:16 -0700928 /*
929 * The only record we have of the real-time age of a
930 * process, regardless of execs it's done, is start_time.
931 * All the past CPU time is accumulated in signal_struct
932 * from sister threads now dead. But in this non-leader
933 * exec, nothing survives from the original leader thread,
934 * whose birth marks the true age of this process now.
935 * When we take on its identity by switching to its PID, we
936 * also take its birthdate (always earlier than our own).
937 */
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -0700938 tsk->start_time = leader->start_time;
Oleg Nesterov266b7a02013-07-03 15:08:35 -0700939 tsk->real_start_time = leader->real_start_time;
Roland McGrathf5e90282006-04-10 22:54:16 -0700940
Pavel Emelyanovbac0abd2007-10-18 23:40:18 -0700941 BUG_ON(!same_thread_group(leader, tsk));
942 BUG_ON(has_group_leader_pid(tsk));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943 /*
944 * An exec() starts a new thread group with the
945 * TGID of the previous thread group. Rehash the
946 * two threads with a switched PID, and release
947 * the former thread group leader:
948 */
Eric W. Biedermand73d6522006-03-28 16:11:03 -0800949
950 /* Become a process group leader with the old leader's pid.
Eric W. Biedermanc18258c2006-09-27 01:51:06 -0700951 * The old leader becomes a thread of the this thread group.
952 * Note: The old leader also uses this pid until release_task
Eric W. Biedermand73d6522006-03-28 16:11:03 -0800953 * is called. Odd but simple and correct.
954 */
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -0700955 tsk->pid = leader->pid;
Oleg Nesterov3f418542013-07-03 15:08:25 -0700956 change_pid(tsk, PIDTYPE_PID, task_pid(leader));
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -0700957 transfer_pid(leader, tsk, PIDTYPE_PGID);
958 transfer_pid(leader, tsk, PIDTYPE_SID);
Oleg Nesterov9cd80bb2009-12-17 15:27:15 -0800959
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -0700960 list_replace_rcu(&leader->tasks, &tsk->tasks);
Oleg Nesterov9cd80bb2009-12-17 15:27:15 -0800961 list_replace_init(&leader->sibling, &tsk->sibling);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -0700963 tsk->group_leader = tsk;
964 leader->group_leader = tsk;
Eric W. Biedermande12a782006-04-10 17:16:49 -0600965
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -0700966 tsk->exit_signal = SIGCHLD;
Oleg Nesterov087806b2011-06-22 23:10:26 +0200967 leader->exit_signal = -1;
Oleg Nesterov962b5642005-11-23 13:37:43 -0800968
969 BUG_ON(leader->exit_state != EXIT_ZOMBIE);
970 leader->exit_state = EXIT_DEAD;
Oleg Nesteroveac1b5e2011-07-21 20:00:43 +0200971
972 /*
973 * We are going to release_task()->ptrace_unlink() silently,
974 * the tracer can sleep in do_wait(). EXIT_DEAD guarantees
975 * the tracer wont't block again waiting for this thread.
976 */
977 if (unlikely(leader->ptrace))
978 __wake_up_parent(leader, leader->parent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979 write_unlock_irq(&tasklist_lock);
Oleg Nesterove56fb282013-04-30 15:28:20 -0700980 threadgroup_change_end(tsk);
Oleg Nesterov81879262008-12-01 14:18:16 -0800981
982 release_task(leader);
Oleg Nesteroved5d2ca2008-02-04 22:27:24 -0800983 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984
Oleg Nesterov6db840f2007-10-16 23:27:23 -0700985 sig->group_exit_task = NULL;
986 sig->notify_count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987
988no_thread_group:
Oleg Nesterove6368252012-03-19 17:03:22 +0100989 /* we have changed execution domain */
990 tsk->exit_signal = SIGCHLD;
991
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992 exit_itimers(sig);
Oleg Nesterovcbaffba2008-05-26 20:55:42 +0400993 flush_itimer_signals();
Oleg Nesterov329f7db2005-11-07 21:12:43 +0300994
Oleg Nesterovb2c903b2007-10-16 23:27:22 -0700995 if (atomic_read(&oldsighand->count) != 1) {
996 struct sighand_struct *newsighand;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700997 /*
Oleg Nesterovb2c903b2007-10-16 23:27:22 -0700998 * This ->sighand is shared with the CLONE_SIGHAND
999 * but not CLONE_THREAD task, switch to the new one.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001000 */
Oleg Nesterovb2c903b2007-10-16 23:27:22 -07001001 newsighand = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);
1002 if (!newsighand)
1003 return -ENOMEM;
1004
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005 atomic_set(&newsighand->count, 1);
1006 memcpy(newsighand->action, oldsighand->action,
1007 sizeof(newsighand->action));
1008
1009 write_lock_irq(&tasklist_lock);
1010 spin_lock(&oldsighand->siglock);
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -07001011 rcu_assign_pointer(tsk->sighand, newsighand);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012 spin_unlock(&oldsighand->siglock);
1013 write_unlock_irq(&tasklist_lock);
1014
Davide Libenzifba2afa2007-05-10 22:23:13 -07001015 __cleanup_sighand(oldsighand);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016 }
1017
Eric W. Biedermanaafe6c22006-09-27 01:51:13 -07001018 BUG_ON(!thread_group_leader(tsk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019 return 0;
Oleg Nesterovd5bbd432012-10-08 19:13:01 +02001020
1021killed:
1022 /* protects against exit_notify() and __exit_signal() */
1023 read_lock(&tasklist_lock);
1024 sig->group_exit_task = NULL;
1025 sig->notify_count = 0;
1026 read_unlock(&tasklist_lock);
1027 return -EAGAIN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028}
Oleg Nesterov0840a902007-10-16 23:27:22 -07001029
Andrew Morton59714d62008-02-04 22:27:21 -08001030char *get_task_comm(char *buf, struct task_struct *tsk)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001031{
1032 /* buf must be at least sizeof(tsk->comm) in size */
1033 task_lock(tsk);
1034 strncpy(buf, tsk->comm, sizeof(tsk->comm));
1035 task_unlock(tsk);
Andrew Morton59714d62008-02-04 22:27:21 -08001036 return buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001037}
J Freyensee7d74f492011-05-06 16:56:47 -07001038EXPORT_SYMBOL_GPL(get_task_comm);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001039
Al Viro6a6d27d2012-08-21 09:56:33 -04001040/*
1041 * These functions flushes out all traces of the currently running executable
1042 * so that a new one can be started
1043 */
1044
Adrian Hunter82b89772014-05-28 11:45:04 +03001045void __set_task_comm(struct task_struct *tsk, const char *buf, bool exec)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046{
1047 task_lock(tsk);
KAMEZAWA Hiroyuki43d2b112012-01-10 15:08:09 -08001048 trace_task_rename(tsk, buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049 strlcpy(tsk->comm, buf, sizeof(tsk->comm));
1050 task_unlock(tsk);
Adrian Hunter82b89772014-05-28 11:45:04 +03001051 perf_event_comm(tsk, exec);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052}
1053
1054int flush_old_exec(struct linux_binprm * bprm)
1055{
Linus Torvalds221af7f2010-01-28 22:14:42 -08001056 int retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001057
1058 /*
1059 * Make sure we have a private signal table and that
1060 * we are unassociated from the previous thread group.
1061 */
1062 retval = de_thread(current);
1063 if (retval)
1064 goto out;
1065
Matt Helsley925d1c42008-04-29 01:01:36 -07001066 set_mm_exe_file(bprm->mm, bprm->file);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001068 * Release all of the old mmap stuff
1069 */
Oleg Nesterov3c77f842010-11-30 20:55:34 +01001070 acct_arg_size(bprm, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001071 retval = exec_mmap(bprm->mm);
1072 if (retval)
Al Virofd8328b2008-04-22 05:11:59 -04001073 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074
1075 bprm->mm = NULL; /* We're using it now */
Linus Torvalds7ab02af2010-02-02 12:37:44 -08001076
Mathias Krausedac853a2011-06-09 20:05:18 +02001077 set_fs(USER_DS);
Zhang Yib88fae62014-01-23 15:55:57 -08001078 current->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD |
1079 PF_NOFREEZE | PF_NO_SETAFFINITY);
Linus Torvalds7ab02af2010-02-02 12:37:44 -08001080 flush_thread();
1081 current->personality &= ~bprm->per_clear;
1082
Linus Torvalds221af7f2010-01-28 22:14:42 -08001083 return 0;
1084
1085out:
1086 return retval;
1087}
1088EXPORT_SYMBOL(flush_old_exec);
1089
Al Viro1b5d7832011-06-19 12:49:47 -04001090void would_dump(struct linux_binprm *bprm, struct file *file)
1091{
Al Viro496ad9a2013-01-23 17:07:38 -05001092 if (inode_permission(file_inode(file), MAY_READ) < 0)
Al Viro1b5d7832011-06-19 12:49:47 -04001093 bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
1094}
1095EXPORT_SYMBOL(would_dump);
1096
Linus Torvalds221af7f2010-01-28 22:14:42 -08001097void setup_new_exec(struct linux_binprm * bprm)
1098{
Linus Torvalds221af7f2010-01-28 22:14:42 -08001099 arch_pick_mmap_layout(current->mm);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001100
1101 /* This is the point of no return */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102 current->sas_ss_sp = current->sas_ss_size = 0;
1103
Eric W. Biederman8e96e3b2012-03-03 21:17:15 -08001104 if (uid_eq(current_euid(), current_uid()) && gid_eq(current_egid(), current_gid()))
Kees Cooke579d2c2013-02-27 17:03:15 -08001105 set_dumpable(current->mm, SUID_DUMP_USER);
Alan Coxd6e71142005-06-23 00:09:43 -07001106 else
Kawai, Hidehiro6c5d5232007-07-19 01:48:27 -07001107 set_dumpable(current->mm, suid_dumpable);
Alan Coxd6e71142005-06-23 00:09:43 -07001108
Peter Zijlstrae041e322014-05-21 17:32:19 +02001109 perf_event_exec();
Adrian Hunter82b89772014-05-28 11:45:04 +03001110 __set_task_comm(current, kbasename(bprm->filename), true);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001111
Benjamin Herrenschmidt0551fbd2006-02-28 16:59:19 -08001112 /* Set the new mm task size. We have to do that late because it may
1113 * depend on TIF_32BIT which is only updated in flush_thread() on
1114 * some architectures like powerpc
1115 */
1116 current->mm->task_size = TASK_SIZE;
1117
David Howellsa6f76f22008-11-14 10:39:24 +11001118 /* install the new credentials */
Eric W. Biederman8e96e3b2012-03-03 21:17:15 -08001119 if (!uid_eq(bprm->cred->uid, current_euid()) ||
1120 !gid_eq(bprm->cred->gid, current_egid())) {
Marcel Holtmannd2d56c52007-08-17 21:47:58 +02001121 current->pdeath_signal = 0;
Al Viro1b5d7832011-06-19 12:49:47 -04001122 } else {
1123 would_dump(bprm, bprm->file);
1124 if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP)
1125 set_dumpable(current->mm, suid_dumpable);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001126 }
1127
1128 /* An exec changes our domain. We are no longer part of the thread
1129 group */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001130 current->self_exec_id++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131 flush_signal_handlers(current, 0);
Al Viro6a6d27d2012-08-21 09:56:33 -04001132 do_close_on_exec(current->files);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001133}
Linus Torvalds221af7f2010-01-28 22:14:42 -08001134EXPORT_SYMBOL(setup_new_exec);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135
David Howellsa6f76f22008-11-14 10:39:24 +11001136/*
Oleg Nesterova2a84742009-09-05 11:17:13 -07001137 * Prepare credentials and lock ->cred_guard_mutex.
1138 * install_exec_creds() commits the new creds and drops the lock.
1139 * Or, if exec fails before, free_bprm() should release ->cred and
1140 * and unlock.
1141 */
1142int prepare_bprm_creds(struct linux_binprm *bprm)
1143{
KOSAKI Motohiro9b1bf122010-10-27 15:34:08 -07001144 if (mutex_lock_interruptible(&current->signal->cred_guard_mutex))
Oleg Nesterova2a84742009-09-05 11:17:13 -07001145 return -ERESTARTNOINTR;
1146
1147 bprm->cred = prepare_exec_creds();
1148 if (likely(bprm->cred))
1149 return 0;
1150
KOSAKI Motohiro9b1bf122010-10-27 15:34:08 -07001151 mutex_unlock(&current->signal->cred_guard_mutex);
Oleg Nesterova2a84742009-09-05 11:17:13 -07001152 return -ENOMEM;
1153}
1154
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001155static void free_bprm(struct linux_binprm *bprm)
Oleg Nesterova2a84742009-09-05 11:17:13 -07001156{
1157 free_arg_pages(bprm);
1158 if (bprm->cred) {
KOSAKI Motohiro9b1bf122010-10-27 15:34:08 -07001159 mutex_unlock(&current->signal->cred_guard_mutex);
Oleg Nesterova2a84742009-09-05 11:17:13 -07001160 abort_creds(bprm->cred);
1161 }
Oleg Nesterov63e46b92014-01-23 15:55:51 -08001162 if (bprm->file) {
1163 allow_write_access(bprm->file);
1164 fput(bprm->file);
1165 }
Kees Cookb66c5982012-12-20 15:05:16 -08001166 /* If a binfmt changed the interp, free it. */
1167 if (bprm->interp != bprm->filename)
1168 kfree(bprm->interp);
Oleg Nesterova2a84742009-09-05 11:17:13 -07001169 kfree(bprm);
1170}
1171
Kees Cookb66c5982012-12-20 15:05:16 -08001172int bprm_change_interp(char *interp, struct linux_binprm *bprm)
1173{
1174 /* If a binfmt changed the interp, free it first. */
1175 if (bprm->interp != bprm->filename)
1176 kfree(bprm->interp);
1177 bprm->interp = kstrdup(interp, GFP_KERNEL);
1178 if (!bprm->interp)
1179 return -ENOMEM;
1180 return 0;
1181}
1182EXPORT_SYMBOL(bprm_change_interp);
1183
Oleg Nesterova2a84742009-09-05 11:17:13 -07001184/*
David Howellsa6f76f22008-11-14 10:39:24 +11001185 * install the new credentials for this executable
1186 */
1187void install_exec_creds(struct linux_binprm *bprm)
1188{
1189 security_bprm_committing_creds(bprm);
1190
1191 commit_creds(bprm->cred);
1192 bprm->cred = NULL;
Stephane Eranian2976b102013-06-20 11:36:28 +02001193
1194 /*
1195 * Disable monitoring for regular users
1196 * when executing setuid binaries. Must
1197 * wait until new credentials are committed
1198 * by commit_creds() above
1199 */
1200 if (get_dumpable(current->mm) != SUID_DUMP_USER)
1201 perf_event_exit_task(current);
Oleg Nesterova2a84742009-09-05 11:17:13 -07001202 /*
1203 * cred_guard_mutex must be held at least to this point to prevent
David Howellsa6f76f22008-11-14 10:39:24 +11001204 * ptrace_attach() from altering our determination of the task's
Oleg Nesterova2a84742009-09-05 11:17:13 -07001205 * credentials; any time after this it may be unlocked.
1206 */
David Howellsa6f76f22008-11-14 10:39:24 +11001207 security_bprm_committed_creds(bprm);
KOSAKI Motohiro9b1bf122010-10-27 15:34:08 -07001208 mutex_unlock(&current->signal->cred_guard_mutex);
David Howellsa6f76f22008-11-14 10:39:24 +11001209}
1210EXPORT_SYMBOL(install_exec_creds);
1211
1212/*
1213 * determine how safe it is to execute the proposed program
KOSAKI Motohiro9b1bf122010-10-27 15:34:08 -07001214 * - the caller must hold ->cred_guard_mutex to protect against
Kees Cookc2e1f2e2014-06-05 00:23:17 -07001215 * PTRACE_ATTACH or seccomp thread-sync
David Howellsa6f76f22008-11-14 10:39:24 +11001216 */
Oleg Nesterov9e00cdb2014-01-23 15:55:50 -08001217static void check_unsafe_exec(struct linux_binprm *bprm)
David Howellsa6f76f22008-11-14 10:39:24 +11001218{
David Howells0bf2f3a2009-02-06 11:45:46 +00001219 struct task_struct *p = current, *t;
Al Virof1191b52009-03-30 07:35:18 -04001220 unsigned n_fs;
David Howellsa6f76f22008-11-14 10:39:24 +11001221
Tejun Heo4b9d33e2011-06-17 16:50:38 +02001222 if (p->ptrace) {
1223 if (p->ptrace & PT_PTRACE_CAP)
1224 bprm->unsafe |= LSM_UNSAFE_PTRACE_CAP;
1225 else
1226 bprm->unsafe |= LSM_UNSAFE_PTRACE;
1227 }
David Howellsa6f76f22008-11-14 10:39:24 +11001228
Andy Lutomirski259e5e62012-04-12 16:47:50 -05001229 /*
1230 * This isn't strictly necessary, but it makes it harder for LSMs to
1231 * mess up.
1232 */
Kees Cook1d4457f2014-05-21 15:23:46 -07001233 if (task_no_new_privs(current))
Andy Lutomirski259e5e62012-04-12 16:47:50 -05001234 bprm->unsafe |= LSM_UNSAFE_NO_NEW_PRIVS;
1235
Oleg Nesterov83f62a22014-01-23 15:55:49 -08001236 t = p;
David Howells0bf2f3a2009-02-06 11:45:46 +00001237 n_fs = 1;
Nick Piggin2a4419b2010-08-18 04:37:33 +10001238 spin_lock(&p->fs->lock);
Oleg Nesterov437f7fd2009-04-24 01:02:45 +02001239 rcu_read_lock();
Oleg Nesterov83f62a22014-01-23 15:55:49 -08001240 while_each_thread(p, t) {
David Howells0bf2f3a2009-02-06 11:45:46 +00001241 if (t->fs == p->fs)
1242 n_fs++;
David Howells0bf2f3a2009-02-06 11:45:46 +00001243 }
Oleg Nesterov437f7fd2009-04-24 01:02:45 +02001244 rcu_read_unlock();
David Howells0bf2f3a2009-02-06 11:45:46 +00001245
Oleg Nesterov9e00cdb2014-01-23 15:55:50 -08001246 if (p->fs->users > n_fs)
David Howellsa6f76f22008-11-14 10:39:24 +11001247 bprm->unsafe |= LSM_UNSAFE_SHARE;
Oleg Nesterov9e00cdb2014-01-23 15:55:50 -08001248 else
1249 p->fs->in_exec = 1;
Nick Piggin2a4419b2010-08-18 04:37:33 +10001250 spin_unlock(&p->fs->lock);
David Howellsa6f76f22008-11-14 10:39:24 +11001251}
1252
Oleg Nesterov9e00cdb2014-01-23 15:55:50 -08001253/*
1254 * Fill the binprm structure from the inode.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001255 * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes
David Howellsa6f76f22008-11-14 10:39:24 +11001256 *
1257 * This may be called multiple times for binary chains (scripts for example).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258 */
1259int prepare_binprm(struct linux_binprm *bprm)
1260{
Al Viro72c2d532013-09-22 16:27:52 -04001261 struct inode *inode = file_inode(bprm->file);
1262 umode_t mode = inode->i_mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263 int retval;
1264
Linus Torvalds1da177e2005-04-16 15:20:36 -07001265
David Howellsa6f76f22008-11-14 10:39:24 +11001266 /* clear any previous set[ug]id data from a previous binary */
1267 bprm->cred->euid = current_euid();
1268 bprm->cred->egid = current_egid();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001269
Andy Lutomirski259e5e62012-04-12 16:47:50 -05001270 if (!(bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) &&
Kees Cook1d4457f2014-05-21 15:23:46 -07001271 !task_no_new_privs(current) &&
Eric W. Biederman3cdf5b42011-11-21 16:40:54 -08001272 kuid_has_mapping(bprm->cred->user_ns, inode->i_uid) &&
1273 kgid_has_mapping(bprm->cred->user_ns, inode->i_gid)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001274 /* Set-uid? */
1275 if (mode & S_ISUID) {
David Howellsa6f76f22008-11-14 10:39:24 +11001276 bprm->per_clear |= PER_CLEAR_ON_SETID;
1277 bprm->cred->euid = inode->i_uid;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001278 }
1279
1280 /* Set-gid? */
1281 /*
1282 * If setgid is set but no group execute bit then this
1283 * is a candidate for mandatory locking, not a setgid
1284 * executable.
1285 */
1286 if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
David Howellsa6f76f22008-11-14 10:39:24 +11001287 bprm->per_clear |= PER_CLEAR_ON_SETID;
1288 bprm->cred->egid = inode->i_gid;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001289 }
1290 }
1291
1292 /* fill in binprm security blob */
David Howellsa6f76f22008-11-14 10:39:24 +11001293 retval = security_bprm_set_creds(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001294 if (retval)
1295 return retval;
David Howellsa6f76f22008-11-14 10:39:24 +11001296 bprm->cred_prepared = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001297
David Howellsa6f76f22008-11-14 10:39:24 +11001298 memset(bprm->buf, 0, BINPRM_BUF_SIZE);
1299 return kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001300}
1301
1302EXPORT_SYMBOL(prepare_binprm);
1303
Nick Piggin4fc75ff2007-05-08 00:25:16 -07001304/*
1305 * Arguments are '\0' separated strings found at the location bprm->p
1306 * points to; chop off the first by relocating brpm->p to right after
1307 * the first '\0' encountered.
1308 */
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001309int remove_arg_zero(struct linux_binprm *bprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001310{
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001311 int ret = 0;
1312 unsigned long offset;
1313 char *kaddr;
1314 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001315
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001316 if (!bprm->argc)
1317 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001318
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001319 do {
1320 offset = bprm->p & ~PAGE_MASK;
1321 page = get_arg_page(bprm, bprm->p, 0);
1322 if (!page) {
1323 ret = -EFAULT;
1324 goto out;
1325 }
Cong Wange8e3c3d2011-11-25 23:14:27 +08001326 kaddr = kmap_atomic(page);
Nick Piggin4fc75ff2007-05-08 00:25:16 -07001327
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001328 for (; offset < PAGE_SIZE && kaddr[offset];
1329 offset++, bprm->p++)
1330 ;
Nick Piggin4fc75ff2007-05-08 00:25:16 -07001331
Cong Wange8e3c3d2011-11-25 23:14:27 +08001332 kunmap_atomic(kaddr);
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001333 put_arg_page(page);
Nick Piggin4fc75ff2007-05-08 00:25:16 -07001334
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001335 if (offset == PAGE_SIZE)
1336 free_arg_page(bprm, (bprm->p >> PAGE_SHIFT) - 1);
1337 } while (offset == PAGE_SIZE);
Nick Piggin4fc75ff2007-05-08 00:25:16 -07001338
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001339 bprm->p++;
1340 bprm->argc--;
1341 ret = 0;
Nick Piggin4fc75ff2007-05-08 00:25:16 -07001342
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001343out:
1344 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001345}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346EXPORT_SYMBOL(remove_arg_zero);
1347
Oleg Nesterovcb7b6b12013-09-11 14:24:44 -07001348#define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001349/*
1350 * cycle the list of binary formats handler, until one recognizes the image
1351 */
Al Viro3c456bf2012-10-20 21:53:31 -04001352int search_binary_handler(struct linux_binprm *bprm)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001353{
Oleg Nesterovcb7b6b12013-09-11 14:24:44 -07001354 bool need_retry = IS_ENABLED(CONFIG_MODULES);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001355 struct linux_binfmt *fmt;
Oleg Nesterovcb7b6b12013-09-11 14:24:44 -07001356 int retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001357
Kees Cookd7402692012-12-17 16:03:20 -08001358 /* This allows 4 levels of binfmt rewrites before failing hard. */
Oleg Nesterov131b2f92013-09-11 14:24:39 -07001359 if (bprm->recursion_depth > 5)
Kees Cookd7402692012-12-17 16:03:20 -08001360 return -ELOOP;
1361
Linus Torvalds1da177e2005-04-16 15:20:36 -07001362 retval = security_bprm_check(bprm);
1363 if (retval)
1364 return retval;
1365
Linus Torvalds1da177e2005-04-16 15:20:36 -07001366 retval = -ENOENT;
Oleg Nesterovcb7b6b12013-09-11 14:24:44 -07001367 retry:
1368 read_lock(&binfmt_lock);
1369 list_for_each_entry(fmt, &formats, lh) {
1370 if (!try_module_get(fmt->module))
1371 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372 read_unlock(&binfmt_lock);
Oleg Nesterovcb7b6b12013-09-11 14:24:44 -07001373 bprm->recursion_depth++;
1374 retval = fmt->load_binary(bprm);
Oleg Nesterovcb7b6b12013-09-11 14:24:44 -07001375 read_lock(&binfmt_lock);
1376 put_binfmt(fmt);
Al Viro19d860a2014-05-04 20:11:36 -04001377 bprm->recursion_depth--;
1378 if (retval < 0 && !bprm->mm) {
1379 /* we got to flush_old_exec() and failed after it */
1380 read_unlock(&binfmt_lock);
1381 force_sigsegv(SIGSEGV, current);
1382 return retval;
1383 }
1384 if (retval != -ENOEXEC || !bprm->file) {
1385 read_unlock(&binfmt_lock);
1386 return retval;
1387 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001388 }
Oleg Nesterovcb7b6b12013-09-11 14:24:44 -07001389 read_unlock(&binfmt_lock);
1390
Al Viro19d860a2014-05-04 20:11:36 -04001391 if (need_retry) {
Oleg Nesterovcb7b6b12013-09-11 14:24:44 -07001392 if (printable(bprm->buf[0]) && printable(bprm->buf[1]) &&
1393 printable(bprm->buf[2]) && printable(bprm->buf[3]))
1394 return retval;
Oleg Nesterov4e0621a2013-09-11 14:24:45 -07001395 if (request_module("binfmt-%04x", *(ushort *)(bprm->buf + 2)) < 0)
1396 return retval;
Oleg Nesterovcb7b6b12013-09-11 14:24:44 -07001397 need_retry = false;
1398 goto retry;
1399 }
1400
Linus Torvalds1da177e2005-04-16 15:20:36 -07001401 return retval;
1402}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001403EXPORT_SYMBOL(search_binary_handler);
1404
Oleg Nesterov5d1baf32013-09-11 14:24:38 -07001405static int exec_binprm(struct linux_binprm *bprm)
1406{
1407 pid_t old_pid, old_vpid;
1408 int ret;
1409
1410 /* Need to fetch pid before load_binary changes it */
1411 old_pid = current->pid;
1412 rcu_read_lock();
1413 old_vpid = task_pid_nr_ns(current, task_active_pid_ns(current->parent));
1414 rcu_read_unlock();
1415
1416 ret = search_binary_handler(bprm);
1417 if (ret >= 0) {
Linus Torvalds3eaded862013-11-21 19:18:14 -08001418 audit_bprm(bprm);
Oleg Nesterov5d1baf32013-09-11 14:24:38 -07001419 trace_sched_process_exec(current, old_pid, bprm);
1420 ptrace_event(PTRACE_EVENT_EXEC, old_vpid);
Oleg Nesterov9beb2662013-09-11 14:24:40 -07001421 proc_exec_connector(current);
Oleg Nesterov5d1baf32013-09-11 14:24:38 -07001422 }
1423
1424 return ret;
1425}
1426
Linus Torvalds1da177e2005-04-16 15:20:36 -07001427/*
1428 * sys_execve() executes a new program.
1429 */
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001430static int do_execve_common(struct filename *filename,
Oleg Nesterovba2d01622011-03-06 18:02:37 +01001431 struct user_arg_ptr argv,
Al Viro835ab322012-10-20 21:50:59 -04001432 struct user_arg_ptr envp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001433{
1434 struct linux_binprm *bprm;
1435 struct file *file;
Al Viro3b125382008-04-22 05:31:30 -04001436 struct files_struct *displaced;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001437 int retval;
Vasiliy Kulikov72fa5992011-08-08 19:02:04 +04001438
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001439 if (IS_ERR(filename))
1440 return PTR_ERR(filename);
1441
Vasiliy Kulikov72fa5992011-08-08 19:02:04 +04001442 /*
1443 * We move the actual failure in case of RLIMIT_NPROC excess from
1444 * set*uid() to execve() because too many poorly written programs
1445 * don't check setuid() return code. Here we additionally recheck
1446 * whether NPROC limit is still exceeded.
1447 */
1448 if ((current->flags & PF_NPROC_EXCEEDED) &&
Oleg Nesterovbd9d43f2013-07-03 15:08:34 -07001449 atomic_read(&current_user()->processes) > rlimit(RLIMIT_NPROC)) {
Vasiliy Kulikov72fa5992011-08-08 19:02:04 +04001450 retval = -EAGAIN;
1451 goto out_ret;
1452 }
1453
1454 /* We're below the limit (still or again), so we don't want to make
1455 * further execve() calls fail. */
1456 current->flags &= ~PF_NPROC_EXCEEDED;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457
Al Viro3b125382008-04-22 05:31:30 -04001458 retval = unshare_files(&displaced);
Al Virofd8328b2008-04-22 05:11:59 -04001459 if (retval)
1460 goto out_ret;
1461
Linus Torvalds1da177e2005-04-16 15:20:36 -07001462 retval = -ENOMEM;
Oliver Neukum11b0b5a2006-03-25 03:08:13 -08001463 bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001464 if (!bprm)
Al Virofd8328b2008-04-22 05:11:59 -04001465 goto out_files;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001466
Oleg Nesterova2a84742009-09-05 11:17:13 -07001467 retval = prepare_bprm_creds(bprm);
1468 if (retval)
David Howellsa6f76f22008-11-14 10:39:24 +11001469 goto out_free;
Al Viro498052b2009-03-30 07:20:30 -04001470
Oleg Nesterov9e00cdb2014-01-23 15:55:50 -08001471 check_unsafe_exec(bprm);
Oleg Nesterova2a84742009-09-05 11:17:13 -07001472 current->in_execve = 1;
David Howellsa6f76f22008-11-14 10:39:24 +11001473
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001474 file = do_open_exec(filename);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001475 retval = PTR_ERR(file);
1476 if (IS_ERR(file))
Al Viro498052b2009-03-30 07:20:30 -04001477 goto out_unmark;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001478
1479 sched_exec();
1480
Linus Torvalds1da177e2005-04-16 15:20:36 -07001481 bprm->file = file;
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001482 bprm->filename = bprm->interp = filename->name;
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001483
1484 retval = bprm_mm_init(bprm);
1485 if (retval)
Oleg Nesterov63e46b92014-01-23 15:55:51 -08001486 goto out_unmark;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001488 bprm->argc = count(argv, MAX_ARG_STRINGS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001489 if ((retval = bprm->argc) < 0)
David Howellsa6f76f22008-11-14 10:39:24 +11001490 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001491
Ollie Wildb6a2fea2007-07-19 01:48:16 -07001492 bprm->envc = count(envp, MAX_ARG_STRINGS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001493 if ((retval = bprm->envc) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001494 goto out;
1495
1496 retval = prepare_binprm(bprm);
1497 if (retval < 0)
1498 goto out;
1499
1500 retval = copy_strings_kernel(1, &bprm->filename, bprm);
1501 if (retval < 0)
1502 goto out;
1503
1504 bprm->exec = bprm->p;
1505 retval = copy_strings(bprm->envc, envp, bprm);
1506 if (retval < 0)
1507 goto out;
1508
1509 retval = copy_strings(bprm->argc, argv, bprm);
1510 if (retval < 0)
1511 goto out;
1512
Oleg Nesterov5d1baf32013-09-11 14:24:38 -07001513 retval = exec_binprm(bprm);
David Howellsa6f76f22008-11-14 10:39:24 +11001514 if (retval < 0)
1515 goto out;
1516
1517 /* execve succeeded */
Al Viro498052b2009-03-30 07:20:30 -04001518 current->fs->in_exec = 0;
Kentaro Takedaf9ce1f12009-02-05 17:18:11 +09001519 current->in_execve = 0;
David Howellsa6f76f22008-11-14 10:39:24 +11001520 acct_update_integrals(current);
Rik van Riel82727012013-10-07 11:29:28 +01001521 task_numa_free(current);
David Howellsa6f76f22008-11-14 10:39:24 +11001522 free_bprm(bprm);
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001523 putname(filename);
David Howellsa6f76f22008-11-14 10:39:24 +11001524 if (displaced)
1525 put_files_struct(displaced);
1526 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001527
1528out:
Oleg Nesterov3c77f842010-11-30 20:55:34 +01001529 if (bprm->mm) {
1530 acct_arg_size(bprm, 0);
1531 mmput(bprm->mm);
1532 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001533
Al Viro498052b2009-03-30 07:20:30 -04001534out_unmark:
Oleg Nesterov9e00cdb2014-01-23 15:55:50 -08001535 current->fs->in_exec = 0;
Kentaro Takedaf9ce1f12009-02-05 17:18:11 +09001536 current->in_execve = 0;
David Howellsa6f76f22008-11-14 10:39:24 +11001537
1538out_free:
Al Viro08a6fac2008-05-10 16:38:25 -04001539 free_bprm(bprm);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001540
Al Virofd8328b2008-04-22 05:11:59 -04001541out_files:
Al Viro3b125382008-04-22 05:31:30 -04001542 if (displaced)
1543 reset_files_struct(displaced);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544out_ret:
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001545 putname(filename);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001546 return retval;
1547}
1548
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001549int do_execve(struct filename *filename,
Oleg Nesterovba2d01622011-03-06 18:02:37 +01001550 const char __user *const __user *__argv,
Al Viroda3d4c52012-10-20 21:49:33 -04001551 const char __user *const __user *__envp)
Oleg Nesterovba2d01622011-03-06 18:02:37 +01001552{
Oleg Nesterov0e028462011-03-06 18:02:54 +01001553 struct user_arg_ptr argv = { .ptr.native = __argv };
1554 struct user_arg_ptr envp = { .ptr.native = __envp };
Al Viro835ab322012-10-20 21:50:59 -04001555 return do_execve_common(filename, argv, envp);
Oleg Nesterovba2d01622011-03-06 18:02:37 +01001556}
1557
Oleg Nesterov0e028462011-03-06 18:02:54 +01001558#ifdef CONFIG_COMPAT
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001559static int compat_do_execve(struct filename *filename,
Al Viro38b983b2012-09-30 13:38:55 -04001560 const compat_uptr_t __user *__argv,
Al Virod03d26e2012-10-20 21:46:25 -04001561 const compat_uptr_t __user *__envp)
Oleg Nesterov0e028462011-03-06 18:02:54 +01001562{
1563 struct user_arg_ptr argv = {
1564 .is_compat = true,
1565 .ptr.compat = __argv,
1566 };
1567 struct user_arg_ptr envp = {
1568 .is_compat = true,
1569 .ptr.compat = __envp,
1570 };
Al Viro835ab322012-10-20 21:50:59 -04001571 return do_execve_common(filename, argv, envp);
Oleg Nesterov0e028462011-03-06 18:02:54 +01001572}
1573#endif
1574
Oleg Nesterov964ee7d2009-09-23 15:56:59 -07001575void set_binfmt(struct linux_binfmt *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001576{
Hiroshi Shimamoto801460d2009-09-23 15:57:41 -07001577 struct mm_struct *mm = current->mm;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001578
Hiroshi Shimamoto801460d2009-09-23 15:57:41 -07001579 if (mm->binfmt)
1580 module_put(mm->binfmt->module);
1581
1582 mm->binfmt = new;
Oleg Nesterov964ee7d2009-09-23 15:56:59 -07001583 if (new)
1584 __module_get(new->module);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001585}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001586EXPORT_SYMBOL(set_binfmt);
1587
Kawai, Hidehiro6c5d5232007-07-19 01:48:27 -07001588/*
Oleg Nesterov7288e112014-01-23 15:55:32 -08001589 * set_dumpable stores three-value SUID_DUMP_* into mm->flags.
Kawai, Hidehiro6c5d5232007-07-19 01:48:27 -07001590 */
1591void set_dumpable(struct mm_struct *mm, int value)
1592{
Oleg Nesterovabacd2f2014-01-23 15:55:31 -08001593 unsigned long old, new;
1594
Oleg Nesterov7288e112014-01-23 15:55:32 -08001595 if (WARN_ON((unsigned)value > SUID_DUMP_ROOT))
1596 return;
1597
Oleg Nesterovabacd2f2014-01-23 15:55:31 -08001598 do {
1599 old = ACCESS_ONCE(mm->flags);
Oleg Nesterov7288e112014-01-23 15:55:32 -08001600 new = (old & ~MMF_DUMPABLE_MASK) | value;
Oleg Nesterovabacd2f2014-01-23 15:55:31 -08001601 } while (cmpxchg(&mm->flags, old, new) != old);
Kawai, Hidehiro6c5d5232007-07-19 01:48:27 -07001602}
Kawai, Hidehiro6c5d5232007-07-19 01:48:27 -07001603
Al Viro38b983b2012-09-30 13:38:55 -04001604SYSCALL_DEFINE3(execve,
1605 const char __user *, filename,
1606 const char __user *const __user *, argv,
1607 const char __user *const __user *, envp)
1608{
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001609 return do_execve(getname(filename), argv, envp);
Al Viro38b983b2012-09-30 13:38:55 -04001610}
1611#ifdef CONFIG_COMPAT
Heiko Carstens625b1d72014-03-04 10:53:50 +01001612COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
1613 const compat_uptr_t __user *, argv,
1614 const compat_uptr_t __user *, envp)
Al Viro38b983b2012-09-30 13:38:55 -04001615{
Linus Torvaldsc4ad8f92014-02-05 12:54:53 -08001616 return compat_do_execve(getname(filename), argv, envp);
Al Viro38b983b2012-09-30 13:38:55 -04001617}
1618#endif