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1 | // SPDX-License-Identifier: GPL-2.0 | |
2 | /* | |
3 | * Many of the syscalls used in this file expect some of the arguments | |
4 | * to be __user pointers not __kernel pointers. To limit the sparse | |
5 | * noise, turn off sparse checking for this file. | |
6 | */ | |
7 | #ifdef __CHECKER__ | |
8 | #undef __CHECKER__ | |
9 | #warning "Sparse checking disabled for this file" | |
10 | #endif | |
11 | ||
12 | #include <linux/init.h> | |
13 | #include <linux/fs.h> | |
14 | #include <linux/slab.h> | |
15 | #include <linux/types.h> | |
16 | #include <linux/fcntl.h> | |
17 | #include <linux/delay.h> | |
18 | #include <linux/string.h> | |
19 | #include <linux/dirent.h> | |
20 | #include <linux/syscalls.h> | |
21 | #include <linux/utime.h> | |
22 | #include <linux/file.h> | |
23 | ||
24 | static ssize_t __init xwrite(int fd, const char *p, size_t count) | |
25 | { | |
26 | ssize_t out = 0; | |
27 | ||
28 | /* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */ | |
29 | while (count) { | |
30 | ssize_t rv = sys_write(fd, p, count); | |
31 | ||
32 | if (rv < 0) { | |
33 | if (rv == -EINTR || rv == -EAGAIN) | |
34 | continue; | |
35 | return out ? out : rv; | |
36 | } else if (rv == 0) | |
37 | break; | |
38 | ||
39 | p += rv; | |
40 | out += rv; | |
41 | count -= rv; | |
42 | } | |
43 | ||
44 | return out; | |
45 | } | |
46 | ||
47 | static __initdata char *message; | |
48 | static void __init error(char *x) | |
49 | { | |
50 | if (!message) | |
51 | message = x; | |
52 | } | |
53 | ||
54 | /* link hash */ | |
55 | ||
56 | #define N_ALIGN(len) ((((len) + 1) & ~3) + 2) | |
57 | ||
58 | static __initdata struct hash { | |
59 | int ino, minor, major; | |
60 | umode_t mode; | |
61 | struct hash *next; | |
62 | char name[N_ALIGN(PATH_MAX)]; | |
63 | } *head[32]; | |
64 | ||
65 | static inline int hash(int major, int minor, int ino) | |
66 | { | |
67 | unsigned long tmp = ino + minor + (major << 3); | |
68 | tmp += tmp >> 5; | |
69 | return tmp & 31; | |
70 | } | |
71 | ||
72 | static char __init *find_link(int major, int minor, int ino, | |
73 | umode_t mode, char *name) | |
74 | { | |
75 | struct hash **p, *q; | |
76 | for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) { | |
77 | if ((*p)->ino != ino) | |
78 | continue; | |
79 | if ((*p)->minor != minor) | |
80 | continue; | |
81 | if ((*p)->major != major) | |
82 | continue; | |
83 | if (((*p)->mode ^ mode) & S_IFMT) | |
84 | continue; | |
85 | return (*p)->name; | |
86 | } | |
87 | q = kmalloc(sizeof(struct hash), GFP_KERNEL); | |
88 | if (!q) | |
89 | panic("can't allocate link hash entry"); | |
90 | q->major = major; | |
91 | q->minor = minor; | |
92 | q->ino = ino; | |
93 | q->mode = mode; | |
94 | strcpy(q->name, name); | |
95 | q->next = NULL; | |
96 | *p = q; | |
97 | return NULL; | |
98 | } | |
99 | ||
100 | static void __init free_hash(void) | |
101 | { | |
102 | struct hash **p, *q; | |
103 | for (p = head; p < head + 32; p++) { | |
104 | while (*p) { | |
105 | q = *p; | |
106 | *p = q->next; | |
107 | kfree(q); | |
108 | } | |
109 | } | |
110 | } | |
111 | ||
112 | static long __init do_utime(char *filename, time64_t mtime) | |
113 | { | |
114 | struct timespec64 t[2]; | |
115 | ||
116 | t[0].tv_sec = mtime; | |
117 | t[0].tv_nsec = 0; | |
118 | t[1].tv_sec = mtime; | |
119 | t[1].tv_nsec = 0; | |
120 | ||
121 | return do_utimes(AT_FDCWD, filename, t, AT_SYMLINK_NOFOLLOW); | |
122 | } | |
123 | ||
124 | static __initdata LIST_HEAD(dir_list); | |
125 | struct dir_entry { | |
126 | struct list_head list; | |
127 | char *name; | |
128 | time64_t mtime; | |
129 | }; | |
130 | ||
131 | static void __init dir_add(const char *name, time64_t mtime) | |
132 | { | |
133 | struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL); | |
134 | if (!de) | |
135 | panic("can't allocate dir_entry buffer"); | |
136 | INIT_LIST_HEAD(&de->list); | |
137 | de->name = kstrdup(name, GFP_KERNEL); | |
138 | de->mtime = mtime; | |
139 | list_add(&de->list, &dir_list); | |
140 | } | |
141 | ||
142 | static void __init dir_utime(void) | |
143 | { | |
144 | struct dir_entry *de, *tmp; | |
145 | list_for_each_entry_safe(de, tmp, &dir_list, list) { | |
146 | list_del(&de->list); | |
147 | do_utime(de->name, de->mtime); | |
148 | kfree(de->name); | |
149 | kfree(de); | |
150 | } | |
151 | } | |
152 | ||
153 | static __initdata time64_t mtime; | |
154 | ||
155 | /* cpio header parsing */ | |
156 | ||
157 | static __initdata unsigned long ino, major, minor, nlink; | |
158 | static __initdata umode_t mode; | |
159 | static __initdata unsigned long body_len, name_len; | |
160 | static __initdata uid_t uid; | |
161 | static __initdata gid_t gid; | |
162 | static __initdata unsigned rdev; | |
163 | ||
164 | static void __init parse_header(char *s) | |
165 | { | |
166 | unsigned long parsed[12]; | |
167 | char buf[9]; | |
168 | int i; | |
169 | ||
170 | buf[8] = '\0'; | |
171 | for (i = 0, s += 6; i < 12; i++, s += 8) { | |
172 | memcpy(buf, s, 8); | |
173 | parsed[i] = simple_strtoul(buf, NULL, 16); | |
174 | } | |
175 | ino = parsed[0]; | |
176 | mode = parsed[1]; | |
177 | uid = parsed[2]; | |
178 | gid = parsed[3]; | |
179 | nlink = parsed[4]; | |
180 | mtime = parsed[5]; /* breaks in y2106 */ | |
181 | body_len = parsed[6]; | |
182 | major = parsed[7]; | |
183 | minor = parsed[8]; | |
184 | rdev = new_encode_dev(MKDEV(parsed[9], parsed[10])); | |
185 | name_len = parsed[11]; | |
186 | } | |
187 | ||
188 | /* FSM */ | |
189 | ||
190 | static __initdata enum state { | |
191 | Start, | |
192 | Collect, | |
193 | GotHeader, | |
194 | SkipIt, | |
195 | GotName, | |
196 | CopyFile, | |
197 | GotSymlink, | |
198 | Reset | |
199 | } state, next_state; | |
200 | ||
201 | static __initdata char *victim; | |
202 | static unsigned long byte_count __initdata; | |
203 | static __initdata loff_t this_header, next_header; | |
204 | ||
205 | static inline void __init eat(unsigned n) | |
206 | { | |
207 | victim += n; | |
208 | this_header += n; | |
209 | byte_count -= n; | |
210 | } | |
211 | ||
212 | static __initdata char *vcollected; | |
213 | static __initdata char *collected; | |
214 | static long remains __initdata; | |
215 | static __initdata char *collect; | |
216 | ||
217 | static void __init read_into(char *buf, unsigned size, enum state next) | |
218 | { | |
219 | if (byte_count >= size) { | |
220 | collected = victim; | |
221 | eat(size); | |
222 | state = next; | |
223 | } else { | |
224 | collect = collected = buf; | |
225 | remains = size; | |
226 | next_state = next; | |
227 | state = Collect; | |
228 | } | |
229 | } | |
230 | ||
231 | static __initdata char *header_buf, *symlink_buf, *name_buf; | |
232 | ||
233 | static int __init do_start(void) | |
234 | { | |
235 | read_into(header_buf, 110, GotHeader); | |
236 | return 0; | |
237 | } | |
238 | ||
239 | static int __init do_collect(void) | |
240 | { | |
241 | unsigned long n = remains; | |
242 | if (byte_count < n) | |
243 | n = byte_count; | |
244 | memcpy(collect, victim, n); | |
245 | eat(n); | |
246 | collect += n; | |
247 | if ((remains -= n) != 0) | |
248 | return 1; | |
249 | state = next_state; | |
250 | return 0; | |
251 | } | |
252 | ||
253 | static int __init do_header(void) | |
254 | { | |
255 | if (memcmp(collected, "070707", 6)==0) { | |
256 | error("incorrect cpio method used: use -H newc option"); | |
257 | return 1; | |
258 | } | |
259 | if (memcmp(collected, "070701", 6)) { | |
260 | error("no cpio magic"); | |
261 | return 1; | |
262 | } | |
263 | parse_header(collected); | |
264 | next_header = this_header + N_ALIGN(name_len) + body_len; | |
265 | next_header = (next_header + 3) & ~3; | |
266 | state = SkipIt; | |
267 | if (name_len <= 0 || name_len > PATH_MAX) | |
268 | return 0; | |
269 | if (S_ISLNK(mode)) { | |
270 | if (body_len > PATH_MAX) | |
271 | return 0; | |
272 | collect = collected = symlink_buf; | |
273 | remains = N_ALIGN(name_len) + body_len; | |
274 | next_state = GotSymlink; | |
275 | state = Collect; | |
276 | return 0; | |
277 | } | |
278 | if (S_ISREG(mode) || !body_len) | |
279 | read_into(name_buf, N_ALIGN(name_len), GotName); | |
280 | return 0; | |
281 | } | |
282 | ||
283 | static int __init do_skip(void) | |
284 | { | |
285 | if (this_header + byte_count < next_header) { | |
286 | eat(byte_count); | |
287 | return 1; | |
288 | } else { | |
289 | eat(next_header - this_header); | |
290 | state = next_state; | |
291 | return 0; | |
292 | } | |
293 | } | |
294 | ||
295 | static int __init do_reset(void) | |
296 | { | |
297 | while (byte_count && *victim == '\0') | |
298 | eat(1); | |
299 | if (byte_count && (this_header & 3)) | |
300 | error("broken padding"); | |
301 | return 1; | |
302 | } | |
303 | ||
304 | static int __init maybe_link(void) | |
305 | { | |
306 | if (nlink >= 2) { | |
307 | char *old = find_link(major, minor, ino, mode, collected); | |
308 | if (old) | |
309 | return (sys_link(old, collected) < 0) ? -1 : 1; | |
310 | } | |
311 | return 0; | |
312 | } | |
313 | ||
314 | static void __init clean_path(char *path, umode_t fmode) | |
315 | { | |
316 | struct kstat st; | |
317 | ||
318 | if (!vfs_lstat(path, &st) && (st.mode ^ fmode) & S_IFMT) { | |
319 | if (S_ISDIR(st.mode)) | |
320 | sys_rmdir(path); | |
321 | else | |
322 | sys_unlink(path); | |
323 | } | |
324 | } | |
325 | ||
326 | static __initdata int wfd; | |
327 | ||
328 | static int __init do_name(void) | |
329 | { | |
330 | state = SkipIt; | |
331 | next_state = Reset; | |
332 | if (strcmp(collected, "TRAILER!!!") == 0) { | |
333 | free_hash(); | |
334 | return 0; | |
335 | } | |
336 | clean_path(collected, mode); | |
337 | if (S_ISREG(mode)) { | |
338 | int ml = maybe_link(); | |
339 | if (ml >= 0) { | |
340 | int openflags = O_WRONLY|O_CREAT; | |
341 | if (ml != 1) | |
342 | openflags |= O_TRUNC; | |
343 | wfd = sys_open(collected, openflags, mode); | |
344 | ||
345 | if (wfd >= 0) { | |
346 | sys_fchown(wfd, uid, gid); | |
347 | sys_fchmod(wfd, mode); | |
348 | if (body_len) | |
349 | sys_ftruncate(wfd, body_len); | |
350 | vcollected = kstrdup(collected, GFP_KERNEL); | |
351 | state = CopyFile; | |
352 | } | |
353 | } | |
354 | } else if (S_ISDIR(mode)) { | |
355 | sys_mkdir(collected, mode); | |
356 | sys_chown(collected, uid, gid); | |
357 | sys_chmod(collected, mode); | |
358 | dir_add(collected, mtime); | |
359 | } else if (S_ISBLK(mode) || S_ISCHR(mode) || | |
360 | S_ISFIFO(mode) || S_ISSOCK(mode)) { | |
361 | if (maybe_link() == 0) { | |
362 | sys_mknod(collected, mode, rdev); | |
363 | sys_chown(collected, uid, gid); | |
364 | sys_chmod(collected, mode); | |
365 | do_utime(collected, mtime); | |
366 | } | |
367 | } | |
368 | return 0; | |
369 | } | |
370 | ||
371 | static int __init do_copy(void) | |
372 | { | |
373 | if (byte_count >= body_len) { | |
374 | if (xwrite(wfd, victim, body_len) != body_len) | |
375 | error("write error"); | |
376 | sys_close(wfd); | |
377 | do_utime(vcollected, mtime); | |
378 | kfree(vcollected); | |
379 | eat(body_len); | |
380 | state = SkipIt; | |
381 | return 0; | |
382 | } else { | |
383 | if (xwrite(wfd, victim, byte_count) != byte_count) | |
384 | error("write error"); | |
385 | body_len -= byte_count; | |
386 | eat(byte_count); | |
387 | return 1; | |
388 | } | |
389 | } | |
390 | ||
391 | static int __init do_symlink(void) | |
392 | { | |
393 | collected[N_ALIGN(name_len) + body_len] = '\0'; | |
394 | clean_path(collected, 0); | |
395 | sys_symlink(collected + N_ALIGN(name_len), collected); | |
396 | sys_lchown(collected, uid, gid); | |
397 | do_utime(collected, mtime); | |
398 | state = SkipIt; | |
399 | next_state = Reset; | |
400 | return 0; | |
401 | } | |
402 | ||
403 | static __initdata int (*actions[])(void) = { | |
404 | [Start] = do_start, | |
405 | [Collect] = do_collect, | |
406 | [GotHeader] = do_header, | |
407 | [SkipIt] = do_skip, | |
408 | [GotName] = do_name, | |
409 | [CopyFile] = do_copy, | |
410 | [GotSymlink] = do_symlink, | |
411 | [Reset] = do_reset, | |
412 | }; | |
413 | ||
414 | static long __init write_buffer(char *buf, unsigned long len) | |
415 | { | |
416 | byte_count = len; | |
417 | victim = buf; | |
418 | ||
419 | while (!actions[state]()) | |
420 | ; | |
421 | return len - byte_count; | |
422 | } | |
423 | ||
424 | static long __init flush_buffer(void *bufv, unsigned long len) | |
425 | { | |
426 | char *buf = (char *) bufv; | |
427 | long written; | |
428 | long origLen = len; | |
429 | if (message) | |
430 | return -1; | |
431 | while ((written = write_buffer(buf, len)) < len && !message) { | |
432 | char c = buf[written]; | |
433 | if (c == '0') { | |
434 | buf += written; | |
435 | len -= written; | |
436 | state = Start; | |
437 | } else if (c == 0) { | |
438 | buf += written; | |
439 | len -= written; | |
440 | state = Reset; | |
441 | } else | |
442 | error("junk in compressed archive"); | |
443 | } | |
444 | return origLen; | |
445 | } | |
446 | ||
447 | static unsigned long my_inptr; /* index of next byte to be processed in inbuf */ | |
448 | ||
449 | #include <linux/decompress/generic.h> | |
450 | ||
451 | static char * __init unpack_to_rootfs(char *buf, unsigned long len) | |
452 | { | |
453 | long written; | |
454 | decompress_fn decompress; | |
455 | const char *compress_name; | |
456 | static __initdata char msg_buf[64]; | |
457 | ||
458 | header_buf = kmalloc(110, GFP_KERNEL); | |
459 | symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL); | |
460 | name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL); | |
461 | ||
462 | if (!header_buf || !symlink_buf || !name_buf) | |
463 | panic("can't allocate buffers"); | |
464 | ||
465 | state = Start; | |
466 | this_header = 0; | |
467 | message = NULL; | |
468 | while (!message && len) { | |
469 | loff_t saved_offset = this_header; | |
470 | if (*buf == '0' && !(this_header & 3)) { | |
471 | state = Start; | |
472 | written = write_buffer(buf, len); | |
473 | buf += written; | |
474 | len -= written; | |
475 | continue; | |
476 | } | |
477 | if (!*buf) { | |
478 | buf++; | |
479 | len--; | |
480 | this_header++; | |
481 | continue; | |
482 | } | |
483 | this_header = 0; | |
484 | decompress = decompress_method(buf, len, &compress_name); | |
485 | pr_debug("Detected %s compressed data\n", compress_name); | |
486 | if (decompress) { | |
487 | int res = decompress(buf, len, NULL, flush_buffer, NULL, | |
488 | &my_inptr, error); | |
489 | if (res) | |
490 | error("decompressor failed"); | |
491 | } else if (compress_name) { | |
492 | if (!message) { | |
493 | snprintf(msg_buf, sizeof msg_buf, | |
494 | "compression method %s not configured", | |
495 | compress_name); | |
496 | message = msg_buf; | |
497 | } | |
498 | } else | |
499 | error("junk in compressed archive"); | |
500 | if (state != Reset) | |
501 | error("junk in compressed archive"); | |
502 | this_header = saved_offset + my_inptr; | |
503 | buf += my_inptr; | |
504 | len -= my_inptr; | |
505 | } | |
506 | dir_utime(); | |
507 | kfree(name_buf); | |
508 | kfree(symlink_buf); | |
509 | kfree(header_buf); | |
510 | return message; | |
511 | } | |
512 | ||
513 | static int __initdata do_retain_initrd; | |
514 | ||
515 | static int __init retain_initrd_param(char *str) | |
516 | { | |
517 | if (*str) | |
518 | return 0; | |
519 | do_retain_initrd = 1; | |
520 | return 1; | |
521 | } | |
522 | __setup("retain_initrd", retain_initrd_param); | |
523 | ||
524 | extern char __initramfs_start[]; | |
525 | extern unsigned long __initramfs_size; | |
526 | #include <linux/initrd.h> | |
527 | #include <linux/kexec.h> | |
528 | ||
529 | static void __init free_initrd(void) | |
530 | { | |
531 | #ifdef CONFIG_KEXEC_CORE | |
532 | unsigned long crashk_start = (unsigned long)__va(crashk_res.start); | |
533 | unsigned long crashk_end = (unsigned long)__va(crashk_res.end); | |
534 | #endif | |
535 | if (do_retain_initrd) | |
536 | goto skip; | |
537 | ||
538 | #ifdef CONFIG_KEXEC_CORE | |
539 | /* | |
540 | * If the initrd region is overlapped with crashkernel reserved region, | |
541 | * free only memory that is not part of crashkernel region. | |
542 | */ | |
543 | if (initrd_start < crashk_end && initrd_end > crashk_start) { | |
544 | /* | |
545 | * Initialize initrd memory region since the kexec boot does | |
546 | * not do. | |
547 | */ | |
548 | memset((void *)initrd_start, 0, initrd_end - initrd_start); | |
549 | if (initrd_start < crashk_start) | |
550 | free_initrd_mem(initrd_start, crashk_start); | |
551 | if (initrd_end > crashk_end) | |
552 | free_initrd_mem(crashk_end, initrd_end); | |
553 | } else | |
554 | #endif | |
555 | free_initrd_mem(initrd_start, initrd_end); | |
556 | skip: | |
557 | initrd_start = 0; | |
558 | initrd_end = 0; | |
559 | } | |
560 | ||
561 | #ifdef CONFIG_BLK_DEV_RAM | |
562 | #define BUF_SIZE 1024 | |
563 | static void __init clean_rootfs(void) | |
564 | { | |
565 | int fd; | |
566 | void *buf; | |
567 | struct linux_dirent64 *dirp; | |
568 | int num; | |
569 | ||
570 | fd = sys_open("/", O_RDONLY, 0); | |
571 | WARN_ON(fd < 0); | |
572 | if (fd < 0) | |
573 | return; | |
574 | buf = kzalloc(BUF_SIZE, GFP_KERNEL); | |
575 | WARN_ON(!buf); | |
576 | if (!buf) { | |
577 | sys_close(fd); | |
578 | return; | |
579 | } | |
580 | ||
581 | dirp = buf; | |
582 | num = sys_getdents64(fd, dirp, BUF_SIZE); | |
583 | while (num > 0) { | |
584 | while (num > 0) { | |
585 | struct kstat st; | |
586 | int ret; | |
587 | ||
588 | ret = vfs_lstat(dirp->d_name, &st); | |
589 | WARN_ON_ONCE(ret); | |
590 | if (!ret) { | |
591 | if (S_ISDIR(st.mode)) | |
592 | sys_rmdir(dirp->d_name); | |
593 | else | |
594 | sys_unlink(dirp->d_name); | |
595 | } | |
596 | ||
597 | num -= dirp->d_reclen; | |
598 | dirp = (void *)dirp + dirp->d_reclen; | |
599 | } | |
600 | dirp = buf; | |
601 | memset(buf, 0, BUF_SIZE); | |
602 | num = sys_getdents64(fd, dirp, BUF_SIZE); | |
603 | } | |
604 | ||
605 | sys_close(fd); | |
606 | kfree(buf); | |
607 | } | |
608 | #endif | |
609 | ||
610 | static int __init populate_rootfs(void) | |
611 | { | |
612 | /* Load the built in initramfs */ | |
613 | char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size); | |
614 | if (err) | |
615 | panic("%s", err); /* Failed to decompress INTERNAL initramfs */ | |
616 | /* If available load the bootloader supplied initrd */ | |
617 | if (initrd_start && !IS_ENABLED(CONFIG_INITRAMFS_FORCE)) { | |
618 | #ifdef CONFIG_BLK_DEV_RAM | |
619 | int fd; | |
620 | printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n"); | |
621 | err = unpack_to_rootfs((char *)initrd_start, | |
622 | initrd_end - initrd_start); | |
623 | if (!err) { | |
624 | free_initrd(); | |
625 | goto done; | |
626 | } else { | |
627 | clean_rootfs(); | |
628 | unpack_to_rootfs(__initramfs_start, __initramfs_size); | |
629 | } | |
630 | printk(KERN_INFO "rootfs image is not initramfs (%s)" | |
631 | "; looks like an initrd\n", err); | |
632 | fd = sys_open("/initrd.image", | |
633 | O_WRONLY|O_CREAT, 0700); | |
634 | if (fd >= 0) { | |
635 | ssize_t written = xwrite(fd, (char *)initrd_start, | |
636 | initrd_end - initrd_start); | |
637 | ||
638 | if (written != initrd_end - initrd_start) | |
639 | pr_err("/initrd.image: incomplete write (%zd != %ld)\n", | |
640 | written, initrd_end - initrd_start); | |
641 | ||
642 | sys_close(fd); | |
643 | free_initrd(); | |
644 | } | |
645 | done: | |
646 | /* empty statement */; | |
647 | #else | |
648 | printk(KERN_INFO "Unpacking initramfs...\n"); | |
649 | err = unpack_to_rootfs((char *)initrd_start, | |
650 | initrd_end - initrd_start); | |
651 | if (err) | |
652 | printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err); | |
653 | free_initrd(); | |
654 | #endif | |
655 | } | |
656 | flush_delayed_fput(); | |
657 | /* | |
658 | * Try loading default modules from initramfs. This gives | |
659 | * us a chance to load before device_initcalls. | |
660 | */ | |
661 | load_default_modules(); | |
662 | ||
663 | return 0; | |
664 | } | |
665 | rootfs_initcall(populate_rootfs); |