Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
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 | ||
1da177e4 LT |
25 | #include <linux/slab.h> |
26 | #include <linux/file.h> | |
9f3acc31 | 27 | #include <linux/fdtable.h> |
ba92a43d | 28 | #include <linux/mm.h> |
615d6e87 | 29 | #include <linux/vmacache.h> |
1da177e4 LT |
30 | #include <linux/stat.h> |
31 | #include <linux/fcntl.h> | |
ba92a43d | 32 | #include <linux/swap.h> |
74aadce9 | 33 | #include <linux/string.h> |
1da177e4 | 34 | #include <linux/init.h> |
ca5b172b | 35 | #include <linux/pagemap.h> |
cdd6c482 | 36 | #include <linux/perf_event.h> |
1da177e4 LT |
37 | #include <linux/highmem.h> |
38 | #include <linux/spinlock.h> | |
39 | #include <linux/key.h> | |
40 | #include <linux/personality.h> | |
41 | #include <linux/binfmts.h> | |
1da177e4 | 42 | #include <linux/utsname.h> |
84d73786 | 43 | #include <linux/pid_namespace.h> |
1da177e4 LT |
44 | #include <linux/module.h> |
45 | #include <linux/namei.h> | |
1da177e4 LT |
46 | #include <linux/mount.h> |
47 | #include <linux/security.h> | |
48 | #include <linux/syscalls.h> | |
8f0ab514 | 49 | #include <linux/tsacct_kern.h> |
9f46080c | 50 | #include <linux/cn_proc.h> |
473ae30b | 51 | #include <linux/audit.h> |
6341c393 | 52 | #include <linux/tracehook.h> |
5f4123be | 53 | #include <linux/kmod.h> |
6110e3ab | 54 | #include <linux/fsnotify.h> |
5ad4e53b | 55 | #include <linux/fs_struct.h> |
61be228a | 56 | #include <linux/pipe_fs_i.h> |
3d5992d2 | 57 | #include <linux/oom.h> |
0e028465 | 58 | #include <linux/compat.h> |
1da177e4 LT |
59 | |
60 | #include <asm/uaccess.h> | |
61 | #include <asm/mmu_context.h> | |
b6a2fea3 | 62 | #include <asm/tlb.h> |
43d2b113 KH |
63 | |
64 | #include <trace/events/task.h> | |
a6f76f23 | 65 | #include "internal.h" |
1da177e4 | 66 | |
4ff16c25 DS |
67 | #include <trace/events/sched.h> |
68 | ||
d6e71144 AC |
69 | int suid_dumpable = 0; |
70 | ||
e4dc1b14 | 71 | static LIST_HEAD(formats); |
1da177e4 LT |
72 | static DEFINE_RWLOCK(binfmt_lock); |
73 | ||
8fc3dc5a | 74 | void __register_binfmt(struct linux_binfmt * fmt, int insert) |
1da177e4 | 75 | { |
8fc3dc5a | 76 | BUG_ON(!fmt); |
92eaa565 ON |
77 | if (WARN_ON(!fmt->load_binary)) |
78 | return; | |
1da177e4 | 79 | write_lock(&binfmt_lock); |
74641f58 IK |
80 | insert ? list_add(&fmt->lh, &formats) : |
81 | list_add_tail(&fmt->lh, &formats); | |
1da177e4 | 82 | write_unlock(&binfmt_lock); |
1da177e4 LT |
83 | } |
84 | ||
74641f58 | 85 | EXPORT_SYMBOL(__register_binfmt); |
1da177e4 | 86 | |
f6b450d4 | 87 | void unregister_binfmt(struct linux_binfmt * fmt) |
1da177e4 | 88 | { |
1da177e4 | 89 | write_lock(&binfmt_lock); |
e4dc1b14 | 90 | list_del(&fmt->lh); |
1da177e4 | 91 | write_unlock(&binfmt_lock); |
1da177e4 LT |
92 | } |
93 | ||
94 | EXPORT_SYMBOL(unregister_binfmt); | |
95 | ||
96 | static inline void put_binfmt(struct linux_binfmt * fmt) | |
97 | { | |
98 | module_put(fmt->module); | |
99 | } | |
100 | ||
69369a70 | 101 | #ifdef CONFIG_USELIB |
1da177e4 LT |
102 | /* |
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 | */ | |
1e7bfb21 | 108 | SYSCALL_DEFINE1(uselib, const char __user *, library) |
1da177e4 | 109 | { |
72c2d531 | 110 | struct linux_binfmt *fmt; |
964bd183 | 111 | struct file *file; |
91a27b2a | 112 | struct filename *tmp = getname(library); |
964bd183 | 113 | int error = PTR_ERR(tmp); |
47c805dc AV |
114 | 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, | |
f9652e10 AV |
117 | .intent = LOOKUP_OPEN, |
118 | .lookup_flags = LOOKUP_FOLLOW, | |
47c805dc | 119 | }; |
964bd183 | 120 | |
6e8341a1 AV |
121 | if (IS_ERR(tmp)) |
122 | goto out; | |
123 | ||
f9652e10 | 124 | file = do_filp_open(AT_FDCWD, tmp, &uselib_flags); |
6e8341a1 AV |
125 | putname(tmp); |
126 | error = PTR_ERR(file); | |
127 | if (IS_ERR(file)) | |
1da177e4 LT |
128 | goto out; |
129 | ||
130 | error = -EINVAL; | |
496ad9aa | 131 | if (!S_ISREG(file_inode(file)->i_mode)) |
1da177e4 LT |
132 | goto exit; |
133 | ||
30524472 | 134 | error = -EACCES; |
6e8341a1 | 135 | if (file->f_path.mnt->mnt_flags & MNT_NOEXEC) |
1da177e4 LT |
136 | goto exit; |
137 | ||
2a12a9d7 | 138 | fsnotify_open(file); |
6110e3ab | 139 | |
1da177e4 | 140 | error = -ENOEXEC; |
1da177e4 | 141 | |
72c2d531 AV |
142 | 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; | |
1da177e4 | 148 | read_unlock(&binfmt_lock); |
72c2d531 AV |
149 | error = fmt->load_shlib(file); |
150 | read_lock(&binfmt_lock); | |
151 | put_binfmt(fmt); | |
152 | if (error != -ENOEXEC) | |
153 | break; | |
1da177e4 | 154 | } |
72c2d531 | 155 | read_unlock(&binfmt_lock); |
6e8341a1 | 156 | exit: |
1da177e4 LT |
157 | fput(file); |
158 | out: | |
159 | return error; | |
1da177e4 | 160 | } |
69369a70 | 161 | #endif /* #ifdef CONFIG_USELIB */ |
1da177e4 | 162 | |
b6a2fea3 | 163 | #ifdef CONFIG_MMU |
ae6b585e ON |
164 | /* |
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 | */ | |
0e028465 | 170 | static void acct_arg_size(struct linux_binprm *bprm, unsigned long pages) |
3c77f845 ON |
171 | { |
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; | |
3c77f845 | 179 | add_mm_counter(mm, MM_ANONPAGES, diff); |
3c77f845 ON |
180 | } |
181 | ||
0e028465 | 182 | static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos, |
b6a2fea3 OW |
183 | int write) |
184 | { | |
185 | struct page *page; | |
186 | int ret; | |
187 | ||
188 | #ifdef CONFIG_STACK_GROWSUP | |
189 | if (write) { | |
d05f3169 | 190 | ret = expand_downwards(bprm->vma, pos); |
b6a2fea3 OW |
191 | 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) { | |
b6a2fea3 | 201 | unsigned long size = bprm->vma->vm_end - bprm->vma->vm_start; |
a64e715f LT |
202 | struct rlimit *rlim; |
203 | ||
3c77f845 ON |
204 | acct_arg_size(bprm, size / PAGE_SIZE); |
205 | ||
a64e715f LT |
206 | /* |
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; | |
b6a2fea3 OW |
212 | |
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 | */ | |
a64e715f | 220 | rlim = current->signal->rlim; |
d554ed89 | 221 | if (size > ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur) / 4) { |
b6a2fea3 OW |
222 | put_page(page); |
223 | return NULL; | |
224 | } | |
225 | } | |
226 | ||
227 | return page; | |
228 | } | |
229 | ||
230 | static void put_arg_page(struct page *page) | |
231 | { | |
232 | put_page(page); | |
233 | } | |
234 | ||
235 | static void free_arg_page(struct linux_binprm *bprm, int i) | |
236 | { | |
237 | } | |
238 | ||
239 | static void free_arg_pages(struct linux_binprm *bprm) | |
240 | { | |
241 | } | |
242 | ||
243 | static 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 | ||
249 | static int __bprm_mm_init(struct linux_binprm *bprm) | |
250 | { | |
eaccbfa5 | 251 | int err; |
b6a2fea3 OW |
252 | 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) | |
eaccbfa5 | 257 | return -ENOMEM; |
b6a2fea3 OW |
258 | |
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 | */ | |
aacb3d17 | 268 | BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP); |
b6a2fea3 OW |
269 | vma->vm_end = STACK_TOP_MAX; |
270 | vma->vm_start = vma->vm_end - PAGE_SIZE; | |
d9104d1c | 271 | vma->vm_flags = VM_SOFTDIRTY | VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP; |
3ed75eb8 | 272 | vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); |
5beb4930 | 273 | INIT_LIST_HEAD(&vma->anon_vma_chain); |
462e635e | 274 | |
b6a2fea3 | 275 | err = insert_vm_struct(mm, vma); |
eaccbfa5 | 276 | if (err) |
b6a2fea3 | 277 | goto err; |
b6a2fea3 OW |
278 | |
279 | mm->stack_vm = mm->total_vm = 1; | |
280 | up_write(&mm->mmap_sem); | |
b6a2fea3 | 281 | bprm->p = vma->vm_end - sizeof(void *); |
b6a2fea3 | 282 | return 0; |
b6a2fea3 | 283 | err: |
eaccbfa5 LFC |
284 | up_write(&mm->mmap_sem); |
285 | bprm->vma = NULL; | |
286 | kmem_cache_free(vm_area_cachep, vma); | |
b6a2fea3 OW |
287 | return err; |
288 | } | |
289 | ||
290 | static bool valid_arg_len(struct linux_binprm *bprm, long len) | |
291 | { | |
292 | return len <= MAX_ARG_STRLEN; | |
293 | } | |
294 | ||
295 | #else | |
296 | ||
0e028465 | 297 | static inline void acct_arg_size(struct linux_binprm *bprm, unsigned long pages) |
3c77f845 ON |
298 | { |
299 | } | |
300 | ||
0e028465 | 301 | static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos, |
b6a2fea3 OW |
302 | 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 | ||
317 | static void put_arg_page(struct page *page) | |
318 | { | |
319 | } | |
320 | ||
321 | static 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 | ||
329 | static 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 | ||
337 | static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos, | |
338 | struct page *page) | |
339 | { | |
340 | } | |
341 | ||
342 | static int __bprm_mm_init(struct linux_binprm *bprm) | |
343 | { | |
344 | bprm->p = PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *); | |
345 | return 0; | |
346 | } | |
347 | ||
348 | static 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 | */ | |
9cc64cea | 361 | static int bprm_mm_init(struct linux_binprm *bprm) |
b6a2fea3 OW |
362 | { |
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 | ||
b6a2fea3 OW |
371 | err = __bprm_mm_init(bprm); |
372 | if (err) | |
373 | goto err; | |
374 | ||
375 | return 0; | |
376 | ||
377 | err: | |
378 | if (mm) { | |
379 | bprm->mm = NULL; | |
380 | mmdrop(mm); | |
381 | } | |
382 | ||
383 | return err; | |
384 | } | |
385 | ||
ba2d0162 | 386 | struct user_arg_ptr { |
0e028465 ON |
387 | #ifdef CONFIG_COMPAT |
388 | bool is_compat; | |
389 | #endif | |
390 | union { | |
391 | const char __user *const __user *native; | |
392 | #ifdef CONFIG_COMPAT | |
38b983b3 | 393 | const compat_uptr_t __user *compat; |
0e028465 ON |
394 | #endif |
395 | } ptr; | |
ba2d0162 ON |
396 | }; |
397 | ||
398 | static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr) | |
1d1dbf81 | 399 | { |
0e028465 ON |
400 | const char __user *native; |
401 | ||
402 | #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); | |
1d1dbf81 | 408 | |
0e028465 ON |
409 | return compat_ptr(compat); |
410 | } | |
411 | #endif | |
412 | ||
413 | if (get_user(native, argv.ptr.native + nr)) | |
1d1dbf81 ON |
414 | return ERR_PTR(-EFAULT); |
415 | ||
0e028465 | 416 | return native; |
1d1dbf81 ON |
417 | } |
418 | ||
1da177e4 LT |
419 | /* |
420 | * count() counts the number of strings in array ARGV. | |
421 | */ | |
ba2d0162 | 422 | static int count(struct user_arg_ptr argv, int max) |
1da177e4 LT |
423 | { |
424 | int i = 0; | |
425 | ||
0e028465 | 426 | if (argv.ptr.native != NULL) { |
1da177e4 | 427 | for (;;) { |
1d1dbf81 | 428 | const char __user *p = get_user_arg_ptr(argv, i); |
1da177e4 | 429 | |
1da177e4 LT |
430 | if (!p) |
431 | break; | |
1d1dbf81 ON |
432 | |
433 | if (IS_ERR(p)) | |
434 | return -EFAULT; | |
435 | ||
6d92d4f6 | 436 | if (i >= max) |
1da177e4 | 437 | return -E2BIG; |
6d92d4f6 | 438 | ++i; |
9aea5a65 RM |
439 | |
440 | if (fatal_signal_pending(current)) | |
441 | return -ERESTARTNOHAND; | |
1da177e4 LT |
442 | cond_resched(); |
443 | } | |
444 | } | |
445 | return i; | |
446 | } | |
447 | ||
448 | /* | |
b6a2fea3 OW |
449 | * '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. | |
1da177e4 | 452 | */ |
ba2d0162 | 453 | static int copy_strings(int argc, struct user_arg_ptr argv, |
75c96f85 | 454 | struct linux_binprm *bprm) |
1da177e4 LT |
455 | { |
456 | struct page *kmapped_page = NULL; | |
457 | char *kaddr = NULL; | |
b6a2fea3 | 458 | unsigned long kpos = 0; |
1da177e4 LT |
459 | int ret; |
460 | ||
461 | while (argc-- > 0) { | |
d7627467 | 462 | const char __user *str; |
1da177e4 LT |
463 | int len; |
464 | unsigned long pos; | |
465 | ||
1d1dbf81 ON |
466 | ret = -EFAULT; |
467 | str = get_user_arg_ptr(argv, argc); | |
468 | if (IS_ERR(str)) | |
1da177e4 | 469 | goto out; |
1da177e4 | 470 | |
1d1dbf81 ON |
471 | len = strnlen_user(str, MAX_ARG_STRLEN); |
472 | if (!len) | |
473 | goto out; | |
474 | ||
475 | ret = -E2BIG; | |
476 | if (!valid_arg_len(bprm, len)) | |
1da177e4 | 477 | goto out; |
1da177e4 | 478 | |
b6a2fea3 | 479 | /* We're going to work our way backwords. */ |
1da177e4 | 480 | pos = bprm->p; |
b6a2fea3 OW |
481 | str += len; |
482 | bprm->p -= len; | |
1da177e4 LT |
483 | |
484 | while (len > 0) { | |
1da177e4 | 485 | int offset, bytes_to_copy; |
1da177e4 | 486 | |
9aea5a65 RM |
487 | if (fatal_signal_pending(current)) { |
488 | ret = -ERESTARTNOHAND; | |
489 | goto out; | |
490 | } | |
7993bc1f RM |
491 | cond_resched(); |
492 | ||
1da177e4 | 493 | offset = pos % PAGE_SIZE; |
b6a2fea3 OW |
494 | 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); | |
1da177e4 | 510 | if (!page) { |
b6a2fea3 | 511 | ret = -E2BIG; |
1da177e4 LT |
512 | goto out; |
513 | } | |
1da177e4 | 514 | |
b6a2fea3 OW |
515 | if (kmapped_page) { |
516 | flush_kernel_dcache_page(kmapped_page); | |
1da177e4 | 517 | kunmap(kmapped_page); |
b6a2fea3 OW |
518 | put_arg_page(kmapped_page); |
519 | } | |
1da177e4 LT |
520 | kmapped_page = page; |
521 | kaddr = kmap(kmapped_page); | |
b6a2fea3 OW |
522 | kpos = pos & PAGE_MASK; |
523 | flush_arg_page(bprm, kpos, kmapped_page); | |
1da177e4 | 524 | } |
b6a2fea3 | 525 | if (copy_from_user(kaddr+offset, str, bytes_to_copy)) { |
1da177e4 LT |
526 | ret = -EFAULT; |
527 | goto out; | |
528 | } | |
1da177e4 LT |
529 | } |
530 | } | |
531 | ret = 0; | |
532 | out: | |
b6a2fea3 OW |
533 | if (kmapped_page) { |
534 | flush_kernel_dcache_page(kmapped_page); | |
1da177e4 | 535 | kunmap(kmapped_page); |
b6a2fea3 OW |
536 | put_arg_page(kmapped_page); |
537 | } | |
1da177e4 LT |
538 | return ret; |
539 | } | |
540 | ||
541 | /* | |
542 | * Like copy_strings, but get argv and its values from kernel memory. | |
543 | */ | |
ba2d0162 | 544 | int copy_strings_kernel(int argc, const char *const *__argv, |
d7627467 | 545 | struct linux_binprm *bprm) |
1da177e4 LT |
546 | { |
547 | int r; | |
548 | mm_segment_t oldfs = get_fs(); | |
ba2d0162 | 549 | struct user_arg_ptr argv = { |
0e028465 | 550 | .ptr.native = (const char __user *const __user *)__argv, |
ba2d0162 ON |
551 | }; |
552 | ||
1da177e4 | 553 | set_fs(KERNEL_DS); |
ba2d0162 | 554 | r = copy_strings(argc, argv, bprm); |
1da177e4 | 555 | set_fs(oldfs); |
ba2d0162 | 556 | |
1da177e4 LT |
557 | return r; |
558 | } | |
1da177e4 LT |
559 | EXPORT_SYMBOL(copy_strings_kernel); |
560 | ||
561 | #ifdef CONFIG_MMU | |
b6a2fea3 | 562 | |
1da177e4 | 563 | /* |
b6a2fea3 OW |
564 | * 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: | |
1da177e4 | 567 | * |
b6a2fea3 OW |
568 | * 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. | |
1da177e4 | 574 | */ |
b6a2fea3 | 575 | static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift) |
1da177e4 LT |
576 | { |
577 | struct mm_struct *mm = vma->vm_mm; | |
b6a2fea3 OW |
578 | 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; | |
d16dfc55 | 583 | struct mmu_gather tlb; |
1da177e4 | 584 | |
b6a2fea3 | 585 | BUG_ON(new_start > new_end); |
1da177e4 | 586 | |
b6a2fea3 OW |
587 | /* |
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 | */ | |
5beb4930 RR |
597 | if (vma_adjust(vma, new_start, old_end, vma->vm_pgoff, NULL)) |
598 | return -ENOMEM; | |
b6a2fea3 OW |
599 | |
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, | |
38a76013 | 605 | vma, new_start, length, false)) |
b6a2fea3 OW |
606 | return -ENOMEM; |
607 | ||
608 | lru_add_drain(); | |
2b047252 | 609 | tlb_gather_mmu(&tlb, mm, old_start, old_end); |
b6a2fea3 OW |
610 | if (new_end > old_start) { |
611 | /* | |
612 | * when the old and new regions overlap clear from new_end. | |
613 | */ | |
d16dfc55 | 614 | free_pgd_range(&tlb, new_end, old_end, new_end, |
6ee8630e | 615 | vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING); |
b6a2fea3 OW |
616 | } 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 | */ | |
d16dfc55 | 623 | free_pgd_range(&tlb, old_start, old_end, new_end, |
6ee8630e | 624 | vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING); |
1da177e4 | 625 | } |
2b047252 | 626 | tlb_finish_mmu(&tlb, old_start, old_end); |
b6a2fea3 OW |
627 | |
628 | /* | |
5beb4930 | 629 | * Shrink the vma to just the new range. Always succeeds. |
b6a2fea3 OW |
630 | */ |
631 | vma_adjust(vma, new_start, new_end, vma->vm_pgoff, NULL); | |
632 | ||
633 | return 0; | |
1da177e4 LT |
634 | } |
635 | ||
b6a2fea3 OW |
636 | /* |
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 | */ | |
1da177e4 LT |
640 | int setup_arg_pages(struct linux_binprm *bprm, |
641 | unsigned long stack_top, | |
642 | int executable_stack) | |
643 | { | |
b6a2fea3 OW |
644 | unsigned long ret; |
645 | unsigned long stack_shift; | |
1da177e4 | 646 | struct mm_struct *mm = current->mm; |
b6a2fea3 OW |
647 | struct vm_area_struct *vma = bprm->vma; |
648 | struct vm_area_struct *prev = NULL; | |
649 | unsigned long vm_flags; | |
650 | unsigned long stack_base; | |
803bf5ec MN |
651 | unsigned long stack_size; |
652 | unsigned long stack_expand; | |
653 | unsigned long rlim_stack; | |
1da177e4 LT |
654 | |
655 | #ifdef CONFIG_STACK_GROWSUP | |
d71f290b | 656 | /* Limit stack size */ |
d554ed89 | 657 | stack_base = rlimit_max(RLIMIT_STACK); |
d71f290b JH |
658 | if (stack_base > STACK_SIZE_MAX) |
659 | stack_base = STACK_SIZE_MAX; | |
1da177e4 | 660 | |
b6a2fea3 OW |
661 | /* Make sure we didn't let the argument array grow too large. */ |
662 | if (vma->vm_end - vma->vm_start > stack_base) | |
663 | return -ENOMEM; | |
1da177e4 | 664 | |
b6a2fea3 | 665 | stack_base = PAGE_ALIGN(stack_top - stack_base); |
1da177e4 | 666 | |
b6a2fea3 OW |
667 | stack_shift = vma->vm_start - stack_base; |
668 | mm->arg_start = bprm->p - stack_shift; | |
669 | bprm->p = vma->vm_end - stack_shift; | |
1da177e4 | 670 | #else |
b6a2fea3 OW |
671 | stack_top = arch_align_stack(stack_top); |
672 | stack_top = PAGE_ALIGN(stack_top); | |
1b528181 RM |
673 | |
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 | ||
b6a2fea3 OW |
678 | stack_shift = vma->vm_end - stack_top; |
679 | ||
680 | bprm->p -= stack_shift; | |
1da177e4 | 681 | mm->arg_start = bprm->p; |
1da177e4 LT |
682 | #endif |
683 | ||
1da177e4 | 684 | if (bprm->loader) |
b6a2fea3 OW |
685 | bprm->loader -= stack_shift; |
686 | bprm->exec -= stack_shift; | |
1da177e4 | 687 | |
1da177e4 | 688 | down_write(&mm->mmap_sem); |
96a8e13e | 689 | vm_flags = VM_STACK_FLAGS; |
b6a2fea3 OW |
690 | |
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; | |
a8bef8ff | 701 | vm_flags |= VM_STACK_INCOMPLETE_SETUP; |
b6a2fea3 OW |
702 | |
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); | |
fc63cf23 AB |
712 | if (ret) |
713 | goto out_unlock; | |
1da177e4 LT |
714 | } |
715 | ||
a8bef8ff MG |
716 | /* mprotect_fixup is overkill to remove the temporary stack flags */ |
717 | vma->vm_flags &= ~VM_STACK_INCOMPLETE_SETUP; | |
718 | ||
5ef097dd | 719 | stack_expand = 131072UL; /* randomly 32*4k (or 2*64k) pages */ |
803bf5ec MN |
720 | 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; | |
b6a2fea3 | 726 | #ifdef CONFIG_STACK_GROWSUP |
803bf5ec MN |
727 | 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; | |
b6a2fea3 | 731 | #else |
803bf5ec MN |
732 | 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; | |
b6a2fea3 | 736 | #endif |
3af9e859 | 737 | current->mm->start_stack = bprm->p; |
b6a2fea3 OW |
738 | ret = expand_stack(vma, stack_base); |
739 | if (ret) | |
740 | ret = -EFAULT; | |
741 | ||
742 | out_unlock: | |
1da177e4 | 743 | up_write(&mm->mmap_sem); |
fc63cf23 | 744 | return ret; |
1da177e4 | 745 | } |
1da177e4 LT |
746 | EXPORT_SYMBOL(setup_arg_pages); |
747 | ||
1da177e4 LT |
748 | #endif /* CONFIG_MMU */ |
749 | ||
c4ad8f98 | 750 | static struct file *do_open_exec(struct filename *name) |
1da177e4 | 751 | { |
1da177e4 | 752 | struct file *file; |
e56b6a5d | 753 | int err; |
47c805dc AV |
754 | static const struct open_flags open_exec_flags = { |
755 | .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC, | |
756 | .acc_mode = MAY_EXEC | MAY_OPEN, | |
f9652e10 AV |
757 | .intent = LOOKUP_OPEN, |
758 | .lookup_flags = LOOKUP_FOLLOW, | |
47c805dc | 759 | }; |
1da177e4 | 760 | |
c4ad8f98 | 761 | file = do_filp_open(AT_FDCWD, name, &open_exec_flags); |
6e8341a1 | 762 | if (IS_ERR(file)) |
e56b6a5d CH |
763 | goto out; |
764 | ||
765 | err = -EACCES; | |
496ad9aa | 766 | if (!S_ISREG(file_inode(file)->i_mode)) |
6e8341a1 | 767 | goto exit; |
e56b6a5d | 768 | |
6e8341a1 AV |
769 | if (file->f_path.mnt->mnt_flags & MNT_NOEXEC) |
770 | goto exit; | |
e56b6a5d | 771 | |
2a12a9d7 | 772 | fsnotify_open(file); |
6110e3ab | 773 | |
e56b6a5d | 774 | err = deny_write_access(file); |
6e8341a1 AV |
775 | if (err) |
776 | goto exit; | |
1da177e4 | 777 | |
6e8341a1 | 778 | out: |
e56b6a5d CH |
779 | return file; |
780 | ||
6e8341a1 AV |
781 | exit: |
782 | fput(file); | |
e56b6a5d CH |
783 | return ERR_PTR(err); |
784 | } | |
c4ad8f98 LT |
785 | |
786 | struct file *open_exec(const char *name) | |
787 | { | |
788 | struct filename tmp = { .name = name }; | |
789 | return do_open_exec(&tmp); | |
790 | } | |
1da177e4 LT |
791 | EXPORT_SYMBOL(open_exec); |
792 | ||
6777d773 MZ |
793 | int kernel_read(struct file *file, loff_t offset, |
794 | char *addr, unsigned long count) | |
1da177e4 LT |
795 | { |
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 | ||
808 | EXPORT_SYMBOL(kernel_read); | |
809 | ||
3dc20cb2 AV |
810 | ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len) |
811 | { | |
ec695579 | 812 | ssize_t res = vfs_read(file, (void __user *)addr, len, &pos); |
3dc20cb2 AV |
813 | if (res > 0) |
814 | flush_icache_range(addr, addr + len); | |
815 | return res; | |
816 | } | |
817 | EXPORT_SYMBOL(read_code); | |
818 | ||
1da177e4 LT |
819 | static int exec_mmap(struct mm_struct *mm) |
820 | { | |
821 | struct task_struct *tsk; | |
615d6e87 | 822 | struct mm_struct *old_mm, *active_mm; |
1da177e4 LT |
823 | |
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) { | |
4fe7efdb | 830 | sync_mm_rss(old_mm); |
1da177e4 LT |
831 | /* |
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 | |
999d9fc1 | 835 | * checking core_state and changing tsk->mm. |
1da177e4 LT |
836 | */ |
837 | down_read(&old_mm->mmap_sem); | |
999d9fc1 | 838 | if (unlikely(old_mm->core_state)) { |
1da177e4 LT |
839 | 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); | |
615d6e87 DB |
848 | tsk->mm->vmacache_seqnum = 0; |
849 | vmacache_flush(tsk); | |
1da177e4 | 850 | task_unlock(tsk); |
1da177e4 LT |
851 | if (old_mm) { |
852 | up_read(&old_mm->mmap_sem); | |
7dddb12c | 853 | BUG_ON(active_mm != old_mm); |
701085b2 | 854 | setmax_mm_hiwater_rss(&tsk->signal->maxrss, old_mm); |
31a78f23 | 855 | mm_update_next_owner(old_mm); |
1da177e4 LT |
856 | 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 | */ | |
858119e1 | 869 | static int de_thread(struct task_struct *tsk) |
1da177e4 LT |
870 | { |
871 | struct signal_struct *sig = tsk->signal; | |
b2c903b8 | 872 | struct sighand_struct *oldsighand = tsk->sighand; |
1da177e4 | 873 | spinlock_t *lock = &oldsighand->siglock; |
1da177e4 | 874 | |
aafe6c2a | 875 | if (thread_group_empty(tsk)) |
1da177e4 LT |
876 | goto no_thread_group; |
877 | ||
878 | /* | |
879 | * Kill all other threads in the thread group. | |
1da177e4 | 880 | */ |
1da177e4 | 881 | spin_lock_irq(lock); |
ed5d2cac | 882 | if (signal_group_exit(sig)) { |
1da177e4 LT |
883 | /* |
884 | * Another group action in progress, just | |
885 | * return so that the signal is processed. | |
886 | */ | |
887 | spin_unlock_irq(lock); | |
1da177e4 LT |
888 | return -EAGAIN; |
889 | } | |
d344193a | 890 | |
ed5d2cac | 891 | sig->group_exit_task = tsk; |
d344193a ON |
892 | sig->notify_count = zap_other_threads(tsk); |
893 | if (!thread_group_leader(tsk)) | |
894 | sig->notify_count--; | |
1da177e4 | 895 | |
d344193a | 896 | while (sig->notify_count) { |
d5bbd43d | 897 | __set_current_state(TASK_KILLABLE); |
1da177e4 LT |
898 | spin_unlock_irq(lock); |
899 | schedule(); | |
d5bbd43d ON |
900 | if (unlikely(__fatal_signal_pending(tsk))) |
901 | goto killed; | |
1da177e4 LT |
902 | spin_lock_irq(lock); |
903 | } | |
1da177e4 LT |
904 | 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 | */ | |
aafe6c2a | 911 | if (!thread_group_leader(tsk)) { |
8187926b | 912 | struct task_struct *leader = tsk->group_leader; |
6db840fa | 913 | |
2800d8d1 | 914 | sig->notify_count = -1; /* for exit_notify() */ |
6db840fa | 915 | for (;;) { |
e56fb287 | 916 | threadgroup_change_begin(tsk); |
6db840fa ON |
917 | write_lock_irq(&tasklist_lock); |
918 | if (likely(leader->exit_state)) | |
919 | break; | |
d5bbd43d | 920 | __set_current_state(TASK_KILLABLE); |
6db840fa | 921 | write_unlock_irq(&tasklist_lock); |
e56fb287 | 922 | threadgroup_change_end(tsk); |
6db840fa | 923 | schedule(); |
d5bbd43d ON |
924 | if (unlikely(__fatal_signal_pending(tsk))) |
925 | goto killed; | |
6db840fa | 926 | } |
1da177e4 | 927 | |
f5e90281 RM |
928 | /* |
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 | */ | |
aafe6c2a | 938 | tsk->start_time = leader->start_time; |
266b7a02 | 939 | tsk->real_start_time = leader->real_start_time; |
f5e90281 | 940 | |
bac0abd6 PE |
941 | BUG_ON(!same_thread_group(leader, tsk)); |
942 | BUG_ON(has_group_leader_pid(tsk)); | |
1da177e4 LT |
943 | /* |
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 | */ | |
d73d6529 EB |
949 | |
950 | /* Become a process group leader with the old leader's pid. | |
c18258c6 EB |
951 | * The old leader becomes a thread of the this thread group. |
952 | * Note: The old leader also uses this pid until release_task | |
d73d6529 EB |
953 | * is called. Odd but simple and correct. |
954 | */ | |
aafe6c2a | 955 | tsk->pid = leader->pid; |
3f418548 | 956 | change_pid(tsk, PIDTYPE_PID, task_pid(leader)); |
aafe6c2a EB |
957 | transfer_pid(leader, tsk, PIDTYPE_PGID); |
958 | transfer_pid(leader, tsk, PIDTYPE_SID); | |
9cd80bbb | 959 | |
aafe6c2a | 960 | list_replace_rcu(&leader->tasks, &tsk->tasks); |
9cd80bbb | 961 | list_replace_init(&leader->sibling, &tsk->sibling); |
1da177e4 | 962 | |
aafe6c2a EB |
963 | tsk->group_leader = tsk; |
964 | leader->group_leader = tsk; | |
de12a787 | 965 | |
aafe6c2a | 966 | tsk->exit_signal = SIGCHLD; |
087806b1 | 967 | leader->exit_signal = -1; |
962b564c ON |
968 | |
969 | BUG_ON(leader->exit_state != EXIT_ZOMBIE); | |
970 | leader->exit_state = EXIT_DEAD; | |
eac1b5e5 ON |
971 | |
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); | |
1da177e4 | 979 | write_unlock_irq(&tasklist_lock); |
e56fb287 | 980 | threadgroup_change_end(tsk); |
8187926b ON |
981 | |
982 | release_task(leader); | |
ed5d2cac | 983 | } |
1da177e4 | 984 | |
6db840fa ON |
985 | sig->group_exit_task = NULL; |
986 | sig->notify_count = 0; | |
1da177e4 LT |
987 | |
988 | no_thread_group: | |
e6368253 ON |
989 | /* we have changed execution domain */ |
990 | tsk->exit_signal = SIGCHLD; | |
991 | ||
1da177e4 | 992 | exit_itimers(sig); |
cbaffba1 | 993 | flush_itimer_signals(); |
329f7dba | 994 | |
b2c903b8 ON |
995 | if (atomic_read(&oldsighand->count) != 1) { |
996 | struct sighand_struct *newsighand; | |
1da177e4 | 997 | /* |
b2c903b8 ON |
998 | * This ->sighand is shared with the CLONE_SIGHAND |
999 | * but not CLONE_THREAD task, switch to the new one. | |
1da177e4 | 1000 | */ |
b2c903b8 ON |
1001 | newsighand = kmem_cache_alloc(sighand_cachep, GFP_KERNEL); |
1002 | if (!newsighand) | |
1003 | return -ENOMEM; | |
1004 | ||
1da177e4 LT |
1005 | 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); | |
aafe6c2a | 1011 | rcu_assign_pointer(tsk->sighand, newsighand); |
1da177e4 LT |
1012 | spin_unlock(&oldsighand->siglock); |
1013 | write_unlock_irq(&tasklist_lock); | |
1014 | ||
fba2afaa | 1015 | __cleanup_sighand(oldsighand); |
1da177e4 LT |
1016 | } |
1017 | ||
aafe6c2a | 1018 | BUG_ON(!thread_group_leader(tsk)); |
1da177e4 | 1019 | return 0; |
d5bbd43d ON |
1020 | |
1021 | killed: | |
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; | |
1da177e4 | 1028 | } |
0840a90d | 1029 | |
59714d65 | 1030 | char *get_task_comm(char *buf, struct task_struct *tsk) |
1da177e4 LT |
1031 | { |
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); | |
59714d65 | 1036 | return buf; |
1da177e4 | 1037 | } |
7d74f492 | 1038 | EXPORT_SYMBOL_GPL(get_task_comm); |
1da177e4 | 1039 | |
6a6d27de AV |
1040 | /* |
1041 | * These functions flushes out all traces of the currently running executable | |
1042 | * so that a new one can be started | |
1043 | */ | |
1044 | ||
82b89778 | 1045 | void __set_task_comm(struct task_struct *tsk, const char *buf, bool exec) |
1da177e4 LT |
1046 | { |
1047 | task_lock(tsk); | |
43d2b113 | 1048 | trace_task_rename(tsk, buf); |
1da177e4 LT |
1049 | strlcpy(tsk->comm, buf, sizeof(tsk->comm)); |
1050 | task_unlock(tsk); | |
82b89778 | 1051 | perf_event_comm(tsk, exec); |
1da177e4 LT |
1052 | } |
1053 | ||
1054 | int flush_old_exec(struct linux_binprm * bprm) | |
1055 | { | |
221af7f8 | 1056 | int retval; |
1da177e4 LT |
1057 | |
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 | ||
925d1c40 | 1066 | set_mm_exe_file(bprm->mm, bprm->file); |
1da177e4 LT |
1067 | /* |
1068 | * Release all of the old mmap stuff | |
1069 | */ | |
3c77f845 | 1070 | acct_arg_size(bprm, 0); |
1da177e4 LT |
1071 | retval = exec_mmap(bprm->mm); |
1072 | if (retval) | |
fd8328be | 1073 | goto out; |
1da177e4 LT |
1074 | |
1075 | bprm->mm = NULL; /* We're using it now */ | |
7ab02af4 | 1076 | |
dac853ae | 1077 | set_fs(USER_DS); |
b88fae64 ZY |
1078 | current->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD | |
1079 | PF_NOFREEZE | PF_NO_SETAFFINITY); | |
7ab02af4 LT |
1080 | flush_thread(); |
1081 | current->personality &= ~bprm->per_clear; | |
1082 | ||
221af7f8 LT |
1083 | return 0; |
1084 | ||
1085 | out: | |
1086 | return retval; | |
1087 | } | |
1088 | EXPORT_SYMBOL(flush_old_exec); | |
1089 | ||
1b5d783c AV |
1090 | void would_dump(struct linux_binprm *bprm, struct file *file) |
1091 | { | |
496ad9aa | 1092 | if (inode_permission(file_inode(file), MAY_READ) < 0) |
1b5d783c AV |
1093 | bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP; |
1094 | } | |
1095 | EXPORT_SYMBOL(would_dump); | |
1096 | ||
221af7f8 LT |
1097 | void setup_new_exec(struct linux_binprm * bprm) |
1098 | { | |
221af7f8 | 1099 | arch_pick_mmap_layout(current->mm); |
1da177e4 LT |
1100 | |
1101 | /* This is the point of no return */ | |
1da177e4 LT |
1102 | current->sas_ss_sp = current->sas_ss_size = 0; |
1103 | ||
8e96e3b7 | 1104 | if (uid_eq(current_euid(), current_uid()) && gid_eq(current_egid(), current_gid())) |
e579d2c2 | 1105 | set_dumpable(current->mm, SUID_DUMP_USER); |
d6e71144 | 1106 | else |
6c5d5238 | 1107 | set_dumpable(current->mm, suid_dumpable); |
d6e71144 | 1108 | |
e041e328 | 1109 | perf_event_exec(); |
82b89778 | 1110 | __set_task_comm(current, kbasename(bprm->filename), true); |
1da177e4 | 1111 | |
0551fbd2 BH |
1112 | /* 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 | ||
a6f76f23 | 1118 | /* install the new credentials */ |
8e96e3b7 EB |
1119 | if (!uid_eq(bprm->cred->uid, current_euid()) || |
1120 | !gid_eq(bprm->cred->gid, current_egid())) { | |
d2d56c5f | 1121 | current->pdeath_signal = 0; |
1b5d783c AV |
1122 | } else { |
1123 | would_dump(bprm, bprm->file); | |
1124 | if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP) | |
1125 | set_dumpable(current->mm, suid_dumpable); | |
1da177e4 LT |
1126 | } |
1127 | ||
1128 | /* An exec changes our domain. We are no longer part of the thread | |
1129 | group */ | |
1da177e4 | 1130 | current->self_exec_id++; |
1da177e4 | 1131 | flush_signal_handlers(current, 0); |
6a6d27de | 1132 | do_close_on_exec(current->files); |
1da177e4 | 1133 | } |
221af7f8 | 1134 | EXPORT_SYMBOL(setup_new_exec); |
1da177e4 | 1135 | |
a2a8474c ON |
1136 | /* |
1137 | * 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 | */ | |
1142 | int prepare_bprm_creds(struct linux_binprm *bprm) | |
1143 | { | |
9b1bf12d | 1144 | if (mutex_lock_interruptible(¤t->signal->cred_guard_mutex)) |
a2a8474c ON |
1145 | return -ERESTARTNOINTR; |
1146 | ||
1147 | bprm->cred = prepare_exec_creds(); | |
1148 | if (likely(bprm->cred)) | |
1149 | return 0; | |
1150 | ||
9b1bf12d | 1151 | mutex_unlock(¤t->signal->cred_guard_mutex); |
a2a8474c ON |
1152 | return -ENOMEM; |
1153 | } | |
1154 | ||
c4ad8f98 | 1155 | static void free_bprm(struct linux_binprm *bprm) |
a2a8474c ON |
1156 | { |
1157 | free_arg_pages(bprm); | |
1158 | if (bprm->cred) { | |
9b1bf12d | 1159 | mutex_unlock(¤t->signal->cred_guard_mutex); |
a2a8474c ON |
1160 | abort_creds(bprm->cred); |
1161 | } | |
63e46b95 ON |
1162 | if (bprm->file) { |
1163 | allow_write_access(bprm->file); | |
1164 | fput(bprm->file); | |
1165 | } | |
b66c5984 KC |
1166 | /* If a binfmt changed the interp, free it. */ |
1167 | if (bprm->interp != bprm->filename) | |
1168 | kfree(bprm->interp); | |
a2a8474c ON |
1169 | kfree(bprm); |
1170 | } | |
1171 | ||
b66c5984 KC |
1172 | int 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 | } | |
1182 | EXPORT_SYMBOL(bprm_change_interp); | |
1183 | ||
a6f76f23 DH |
1184 | /* |
1185 | * install the new credentials for this executable | |
1186 | */ | |
1187 | void install_exec_creds(struct linux_binprm *bprm) | |
1188 | { | |
1189 | security_bprm_committing_creds(bprm); | |
1190 | ||
1191 | commit_creds(bprm->cred); | |
1192 | bprm->cred = NULL; | |
2976b10f SE |
1193 | |
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); | |
a2a8474c ON |
1202 | /* |
1203 | * cred_guard_mutex must be held at least to this point to prevent | |
a6f76f23 | 1204 | * ptrace_attach() from altering our determination of the task's |
a2a8474c ON |
1205 | * credentials; any time after this it may be unlocked. |
1206 | */ | |
a6f76f23 | 1207 | security_bprm_committed_creds(bprm); |
9b1bf12d | 1208 | mutex_unlock(¤t->signal->cred_guard_mutex); |
a6f76f23 DH |
1209 | } |
1210 | EXPORT_SYMBOL(install_exec_creds); | |
1211 | ||
1212 | /* | |
1213 | * determine how safe it is to execute the proposed program | |
9b1bf12d | 1214 | * - the caller must hold ->cred_guard_mutex to protect against |
c2e1f2e3 | 1215 | * PTRACE_ATTACH or seccomp thread-sync |
a6f76f23 | 1216 | */ |
9e00cdb0 | 1217 | static void check_unsafe_exec(struct linux_binprm *bprm) |
a6f76f23 | 1218 | { |
0bf2f3ae | 1219 | struct task_struct *p = current, *t; |
f1191b50 | 1220 | unsigned n_fs; |
a6f76f23 | 1221 | |
4b9d33e6 TH |
1222 | 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 | } | |
a6f76f23 | 1228 | |
259e5e6c AL |
1229 | /* |
1230 | * This isn't strictly necessary, but it makes it harder for LSMs to | |
1231 | * mess up. | |
1232 | */ | |
1d4457f9 | 1233 | if (task_no_new_privs(current)) |
259e5e6c AL |
1234 | bprm->unsafe |= LSM_UNSAFE_NO_NEW_PRIVS; |
1235 | ||
83f62a2e | 1236 | t = p; |
0bf2f3ae | 1237 | n_fs = 1; |
2a4419b5 | 1238 | spin_lock(&p->fs->lock); |
437f7fdb | 1239 | rcu_read_lock(); |
83f62a2e | 1240 | while_each_thread(p, t) { |
0bf2f3ae DH |
1241 | if (t->fs == p->fs) |
1242 | n_fs++; | |
0bf2f3ae | 1243 | } |
437f7fdb | 1244 | rcu_read_unlock(); |
0bf2f3ae | 1245 | |
9e00cdb0 | 1246 | if (p->fs->users > n_fs) |
a6f76f23 | 1247 | bprm->unsafe |= LSM_UNSAFE_SHARE; |
9e00cdb0 ON |
1248 | else |
1249 | p->fs->in_exec = 1; | |
2a4419b5 | 1250 | spin_unlock(&p->fs->lock); |
a6f76f23 DH |
1251 | } |
1252 | ||
9e00cdb0 ON |
1253 | /* |
1254 | * Fill the binprm structure from the inode. | |
1da177e4 | 1255 | * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes |
a6f76f23 DH |
1256 | * |
1257 | * This may be called multiple times for binary chains (scripts for example). | |
1da177e4 LT |
1258 | */ |
1259 | int prepare_binprm(struct linux_binprm *bprm) | |
1260 | { | |
72c2d531 AV |
1261 | struct inode *inode = file_inode(bprm->file); |
1262 | umode_t mode = inode->i_mode; | |
1da177e4 LT |
1263 | int retval; |
1264 | ||
1da177e4 | 1265 | |
a6f76f23 DH |
1266 | /* clear any previous set[ug]id data from a previous binary */ |
1267 | bprm->cred->euid = current_euid(); | |
1268 | bprm->cred->egid = current_egid(); | |
1da177e4 | 1269 | |
259e5e6c | 1270 | if (!(bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) && |
1d4457f9 | 1271 | !task_no_new_privs(current) && |
3cdf5b45 EB |
1272 | kuid_has_mapping(bprm->cred->user_ns, inode->i_uid) && |
1273 | kgid_has_mapping(bprm->cred->user_ns, inode->i_gid)) { | |
1da177e4 LT |
1274 | /* Set-uid? */ |
1275 | if (mode & S_ISUID) { | |
a6f76f23 DH |
1276 | bprm->per_clear |= PER_CLEAR_ON_SETID; |
1277 | bprm->cred->euid = inode->i_uid; | |
1da177e4 LT |
1278 | } |
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)) { | |
a6f76f23 DH |
1287 | bprm->per_clear |= PER_CLEAR_ON_SETID; |
1288 | bprm->cred->egid = inode->i_gid; | |
1da177e4 LT |
1289 | } |
1290 | } | |
1291 | ||
1292 | /* fill in binprm security blob */ | |
a6f76f23 | 1293 | retval = security_bprm_set_creds(bprm); |
1da177e4 LT |
1294 | if (retval) |
1295 | return retval; | |
a6f76f23 | 1296 | bprm->cred_prepared = 1; |
1da177e4 | 1297 | |
a6f76f23 DH |
1298 | memset(bprm->buf, 0, BINPRM_BUF_SIZE); |
1299 | return kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE); | |
1da177e4 LT |
1300 | } |
1301 | ||
1302 | EXPORT_SYMBOL(prepare_binprm); | |
1303 | ||
4fc75ff4 NP |
1304 | /* |
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 | */ | |
b6a2fea3 | 1309 | int remove_arg_zero(struct linux_binprm *bprm) |
1da177e4 | 1310 | { |
b6a2fea3 OW |
1311 | int ret = 0; |
1312 | unsigned long offset; | |
1313 | char *kaddr; | |
1314 | struct page *page; | |
4fc75ff4 | 1315 | |
b6a2fea3 OW |
1316 | if (!bprm->argc) |
1317 | return 0; | |
1da177e4 | 1318 | |
b6a2fea3 OW |
1319 | 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 | } | |
e8e3c3d6 | 1326 | kaddr = kmap_atomic(page); |
4fc75ff4 | 1327 | |
b6a2fea3 OW |
1328 | for (; offset < PAGE_SIZE && kaddr[offset]; |
1329 | offset++, bprm->p++) | |
1330 | ; | |
4fc75ff4 | 1331 | |
e8e3c3d6 | 1332 | kunmap_atomic(kaddr); |
b6a2fea3 | 1333 | put_arg_page(page); |
4fc75ff4 | 1334 | |
b6a2fea3 OW |
1335 | if (offset == PAGE_SIZE) |
1336 | free_arg_page(bprm, (bprm->p >> PAGE_SHIFT) - 1); | |
1337 | } while (offset == PAGE_SIZE); | |
4fc75ff4 | 1338 | |
b6a2fea3 OW |
1339 | bprm->p++; |
1340 | bprm->argc--; | |
1341 | ret = 0; | |
4fc75ff4 | 1342 | |
b6a2fea3 OW |
1343 | out: |
1344 | return ret; | |
1da177e4 | 1345 | } |
1da177e4 LT |
1346 | EXPORT_SYMBOL(remove_arg_zero); |
1347 | ||
cb7b6b1c | 1348 | #define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e)) |
1da177e4 LT |
1349 | /* |
1350 | * cycle the list of binary formats handler, until one recognizes the image | |
1351 | */ | |
3c456bfc | 1352 | int search_binary_handler(struct linux_binprm *bprm) |
1da177e4 | 1353 | { |
cb7b6b1c | 1354 | bool need_retry = IS_ENABLED(CONFIG_MODULES); |
1da177e4 | 1355 | struct linux_binfmt *fmt; |
cb7b6b1c | 1356 | int retval; |
1da177e4 | 1357 | |
d7402698 | 1358 | /* This allows 4 levels of binfmt rewrites before failing hard. */ |
131b2f9f | 1359 | if (bprm->recursion_depth > 5) |
d7402698 KC |
1360 | return -ELOOP; |
1361 | ||
1da177e4 LT |
1362 | retval = security_bprm_check(bprm); |
1363 | if (retval) | |
1364 | return retval; | |
1365 | ||
1da177e4 | 1366 | retval = -ENOENT; |
cb7b6b1c ON |
1367 | retry: |
1368 | read_lock(&binfmt_lock); | |
1369 | list_for_each_entry(fmt, &formats, lh) { | |
1370 | if (!try_module_get(fmt->module)) | |
1371 | continue; | |
1372 | read_unlock(&binfmt_lock); | |
1373 | bprm->recursion_depth++; | |
1374 | retval = fmt->load_binary(bprm); | |
1375 | bprm->recursion_depth--; | |
6b3c538f ON |
1376 | if (retval >= 0 || retval != -ENOEXEC || |
1377 | bprm->mm == NULL || bprm->file == NULL) { | |
1da177e4 | 1378 | put_binfmt(fmt); |
cb7b6b1c | 1379 | return retval; |
1da177e4 | 1380 | } |
cb7b6b1c ON |
1381 | read_lock(&binfmt_lock); |
1382 | put_binfmt(fmt); | |
1da177e4 | 1383 | } |
cb7b6b1c ON |
1384 | read_unlock(&binfmt_lock); |
1385 | ||
6b3c538f | 1386 | if (need_retry && retval == -ENOEXEC) { |
cb7b6b1c ON |
1387 | if (printable(bprm->buf[0]) && printable(bprm->buf[1]) && |
1388 | printable(bprm->buf[2]) && printable(bprm->buf[3])) | |
1389 | return retval; | |
4e0621a0 ON |
1390 | if (request_module("binfmt-%04x", *(ushort *)(bprm->buf + 2)) < 0) |
1391 | return retval; | |
cb7b6b1c ON |
1392 | need_retry = false; |
1393 | goto retry; | |
1394 | } | |
1395 | ||
1da177e4 LT |
1396 | return retval; |
1397 | } | |
1da177e4 LT |
1398 | EXPORT_SYMBOL(search_binary_handler); |
1399 | ||
5d1baf3b ON |
1400 | static int exec_binprm(struct linux_binprm *bprm) |
1401 | { | |
1402 | pid_t old_pid, old_vpid; | |
1403 | int ret; | |
1404 | ||
1405 | /* Need to fetch pid before load_binary changes it */ | |
1406 | old_pid = current->pid; | |
1407 | rcu_read_lock(); | |
1408 | old_vpid = task_pid_nr_ns(current, task_active_pid_ns(current->parent)); | |
1409 | rcu_read_unlock(); | |
1410 | ||
1411 | ret = search_binary_handler(bprm); | |
1412 | if (ret >= 0) { | |
3eaded86 | 1413 | audit_bprm(bprm); |
5d1baf3b ON |
1414 | trace_sched_process_exec(current, old_pid, bprm); |
1415 | ptrace_event(PTRACE_EVENT_EXEC, old_vpid); | |
9beb266f | 1416 | proc_exec_connector(current); |
5d1baf3b ON |
1417 | } |
1418 | ||
1419 | return ret; | |
1420 | } | |
1421 | ||
1da177e4 LT |
1422 | /* |
1423 | * sys_execve() executes a new program. | |
1424 | */ | |
c4ad8f98 | 1425 | static int do_execve_common(struct filename *filename, |
ba2d0162 | 1426 | struct user_arg_ptr argv, |
835ab32d | 1427 | struct user_arg_ptr envp) |
1da177e4 LT |
1428 | { |
1429 | struct linux_binprm *bprm; | |
1430 | struct file *file; | |
3b125388 | 1431 | struct files_struct *displaced; |
1da177e4 | 1432 | int retval; |
72fa5997 | 1433 | |
c4ad8f98 LT |
1434 | if (IS_ERR(filename)) |
1435 | return PTR_ERR(filename); | |
1436 | ||
72fa5997 VK |
1437 | /* |
1438 | * We move the actual failure in case of RLIMIT_NPROC excess from | |
1439 | * set*uid() to execve() because too many poorly written programs | |
1440 | * don't check setuid() return code. Here we additionally recheck | |
1441 | * whether NPROC limit is still exceeded. | |
1442 | */ | |
1443 | if ((current->flags & PF_NPROC_EXCEEDED) && | |
bd9d43f4 | 1444 | atomic_read(¤t_user()->processes) > rlimit(RLIMIT_NPROC)) { |
72fa5997 VK |
1445 | retval = -EAGAIN; |
1446 | goto out_ret; | |
1447 | } | |
1448 | ||
1449 | /* We're below the limit (still or again), so we don't want to make | |
1450 | * further execve() calls fail. */ | |
1451 | current->flags &= ~PF_NPROC_EXCEEDED; | |
1da177e4 | 1452 | |
3b125388 | 1453 | retval = unshare_files(&displaced); |
fd8328be AV |
1454 | if (retval) |
1455 | goto out_ret; | |
1456 | ||
1da177e4 | 1457 | retval = -ENOMEM; |
11b0b5ab | 1458 | bprm = kzalloc(sizeof(*bprm), GFP_KERNEL); |
1da177e4 | 1459 | if (!bprm) |
fd8328be | 1460 | goto out_files; |
1da177e4 | 1461 | |
a2a8474c ON |
1462 | retval = prepare_bprm_creds(bprm); |
1463 | if (retval) | |
a6f76f23 | 1464 | goto out_free; |
498052bb | 1465 | |
9e00cdb0 | 1466 | check_unsafe_exec(bprm); |
a2a8474c | 1467 | current->in_execve = 1; |
a6f76f23 | 1468 | |
c4ad8f98 | 1469 | file = do_open_exec(filename); |
1da177e4 LT |
1470 | retval = PTR_ERR(file); |
1471 | if (IS_ERR(file)) | |
498052bb | 1472 | goto out_unmark; |
1da177e4 LT |
1473 | |
1474 | sched_exec(); | |
1475 | ||
1da177e4 | 1476 | bprm->file = file; |
c4ad8f98 | 1477 | bprm->filename = bprm->interp = filename->name; |
1da177e4 | 1478 | |
b6a2fea3 OW |
1479 | retval = bprm_mm_init(bprm); |
1480 | if (retval) | |
63e46b95 | 1481 | goto out_unmark; |
1da177e4 | 1482 | |
b6a2fea3 | 1483 | bprm->argc = count(argv, MAX_ARG_STRINGS); |
1da177e4 | 1484 | if ((retval = bprm->argc) < 0) |
a6f76f23 | 1485 | goto out; |
1da177e4 | 1486 | |
b6a2fea3 | 1487 | bprm->envc = count(envp, MAX_ARG_STRINGS); |
1da177e4 | 1488 | if ((retval = bprm->envc) < 0) |
1da177e4 LT |
1489 | goto out; |
1490 | ||
1491 | retval = prepare_binprm(bprm); | |
1492 | if (retval < 0) | |
1493 | goto out; | |
1494 | ||
1495 | retval = copy_strings_kernel(1, &bprm->filename, bprm); | |
1496 | if (retval < 0) | |
1497 | goto out; | |
1498 | ||
1499 | bprm->exec = bprm->p; | |
1500 | retval = copy_strings(bprm->envc, envp, bprm); | |
1501 | if (retval < 0) | |
1502 | goto out; | |
1503 | ||
1504 | retval = copy_strings(bprm->argc, argv, bprm); | |
1505 | if (retval < 0) | |
1506 | goto out; | |
1507 | ||
5d1baf3b | 1508 | retval = exec_binprm(bprm); |
a6f76f23 DH |
1509 | if (retval < 0) |
1510 | goto out; | |
1da177e4 | 1511 | |
a6f76f23 | 1512 | /* execve succeeded */ |
498052bb | 1513 | current->fs->in_exec = 0; |
f9ce1f1c | 1514 | current->in_execve = 0; |
a6f76f23 | 1515 | acct_update_integrals(current); |
82727018 | 1516 | task_numa_free(current); |
a6f76f23 | 1517 | free_bprm(bprm); |
c4ad8f98 | 1518 | putname(filename); |
a6f76f23 DH |
1519 | if (displaced) |
1520 | put_files_struct(displaced); | |
1521 | return retval; | |
1da177e4 | 1522 | |
a6f76f23 | 1523 | out: |
3c77f845 ON |
1524 | if (bprm->mm) { |
1525 | acct_arg_size(bprm, 0); | |
1526 | mmput(bprm->mm); | |
1527 | } | |
1da177e4 | 1528 | |
498052bb | 1529 | out_unmark: |
9e00cdb0 | 1530 | current->fs->in_exec = 0; |
f9ce1f1c | 1531 | current->in_execve = 0; |
a6f76f23 DH |
1532 | |
1533 | out_free: | |
08a6fac1 | 1534 | free_bprm(bprm); |
1da177e4 | 1535 | |
fd8328be | 1536 | out_files: |
3b125388 AV |
1537 | if (displaced) |
1538 | reset_files_struct(displaced); | |
1da177e4 | 1539 | out_ret: |
c4ad8f98 | 1540 | putname(filename); |
1da177e4 LT |
1541 | return retval; |
1542 | } | |
1543 | ||
c4ad8f98 | 1544 | int do_execve(struct filename *filename, |
ba2d0162 | 1545 | const char __user *const __user *__argv, |
da3d4c5f | 1546 | const char __user *const __user *__envp) |
ba2d0162 | 1547 | { |
0e028465 ON |
1548 | struct user_arg_ptr argv = { .ptr.native = __argv }; |
1549 | struct user_arg_ptr envp = { .ptr.native = __envp }; | |
835ab32d | 1550 | return do_execve_common(filename, argv, envp); |
0e028465 ON |
1551 | } |
1552 | ||
1553 | #ifdef CONFIG_COMPAT | |
c4ad8f98 | 1554 | static int compat_do_execve(struct filename *filename, |
38b983b3 | 1555 | const compat_uptr_t __user *__argv, |
d03d26e5 | 1556 | const compat_uptr_t __user *__envp) |
0e028465 ON |
1557 | { |
1558 | struct user_arg_ptr argv = { | |
1559 | .is_compat = true, | |
1560 | .ptr.compat = __argv, | |
1561 | }; | |
1562 | struct user_arg_ptr envp = { | |
1563 | .is_compat = true, | |
1564 | .ptr.compat = __envp, | |
1565 | }; | |
835ab32d | 1566 | return do_execve_common(filename, argv, envp); |
ba2d0162 | 1567 | } |
0e028465 | 1568 | #endif |
ba2d0162 | 1569 | |
964ee7df | 1570 | void set_binfmt(struct linux_binfmt *new) |
1da177e4 | 1571 | { |
801460d0 HS |
1572 | struct mm_struct *mm = current->mm; |
1573 | ||
1574 | if (mm->binfmt) | |
1575 | module_put(mm->binfmt->module); | |
1da177e4 | 1576 | |
801460d0 | 1577 | mm->binfmt = new; |
964ee7df ON |
1578 | if (new) |
1579 | __module_get(new->module); | |
1da177e4 | 1580 | } |
1da177e4 LT |
1581 | EXPORT_SYMBOL(set_binfmt); |
1582 | ||
6c5d5238 | 1583 | /* |
7288e118 | 1584 | * set_dumpable stores three-value SUID_DUMP_* into mm->flags. |
6c5d5238 KH |
1585 | */ |
1586 | void set_dumpable(struct mm_struct *mm, int value) | |
1587 | { | |
abacd2fe ON |
1588 | unsigned long old, new; |
1589 | ||
7288e118 ON |
1590 | if (WARN_ON((unsigned)value > SUID_DUMP_ROOT)) |
1591 | return; | |
1592 | ||
abacd2fe ON |
1593 | do { |
1594 | old = ACCESS_ONCE(mm->flags); | |
7288e118 | 1595 | new = (old & ~MMF_DUMPABLE_MASK) | value; |
abacd2fe | 1596 | } while (cmpxchg(&mm->flags, old, new) != old); |
6c5d5238 | 1597 | } |
6c5d5238 | 1598 | |
38b983b3 AV |
1599 | SYSCALL_DEFINE3(execve, |
1600 | const char __user *, filename, | |
1601 | const char __user *const __user *, argv, | |
1602 | const char __user *const __user *, envp) | |
1603 | { | |
c4ad8f98 | 1604 | return do_execve(getname(filename), argv, envp); |
38b983b3 AV |
1605 | } |
1606 | #ifdef CONFIG_COMPAT | |
625b1d7e HC |
1607 | COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename, |
1608 | const compat_uptr_t __user *, argv, | |
1609 | const compat_uptr_t __user *, envp) | |
38b983b3 | 1610 | { |
c4ad8f98 | 1611 | return compat_do_execve(getname(filename), argv, envp); |
38b983b3 AV |
1612 | } |
1613 | #endif |