1
2#include <linux/init.h>
3#include <linux/async.h>
4#include <linux/fs.h>
5#include <linux/slab.h>
6#include <linux/types.h>
7#include <linux/fcntl.h>
8#include <linux/delay.h>
9#include <linux/string.h>
10#include <linux/dirent.h>
11#include <linux/syscalls.h>
12#include <linux/utime.h>
13#include <linux/file.h>
14#include <linux/memblock.h>
15#include <linux/mm.h>
16#include <linux/namei.h>
17#include <linux/init_syscalls.h>
18
19static ssize_t __init xwrite(struct file *file, const char *p, size_t count,
20 loff_t *pos)
21{
22 ssize_t out = 0;
23
24
25 while (count) {
26 ssize_t rv = kernel_write(file, p, count, pos);
27
28 if (rv < 0) {
29 if (rv == -EINTR || rv == -EAGAIN)
30 continue;
31 return out ? out : rv;
32 } else if (rv == 0)
33 break;
34
35 p += rv;
36 out += rv;
37 count -= rv;
38 }
39
40 return out;
41}
42
43static __initdata char *message;
44static void __init error(char *x)
45{
46 if (!message)
47 message = x;
48}
49
50static void panic_show_mem(const char *fmt, ...)
51{
52 va_list args;
53
54 show_mem(0, NULL);
55 va_start(args, fmt);
56 panic(fmt, args);
57 va_end(args);
58}
59
60
61
62#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
63
64static __initdata struct hash {
65 int ino, minor, major;
66 umode_t mode;
67 struct hash *next;
68 char name[N_ALIGN(PATH_MAX)];
69} *head[32];
70
71static inline int hash(int major, int minor, int ino)
72{
73 unsigned long tmp = ino + minor + (major << 3);
74 tmp += tmp >> 5;
75 return tmp & 31;
76}
77
78static char __init *find_link(int major, int minor, int ino,
79 umode_t mode, char *name)
80{
81 struct hash **p, *q;
82 for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
83 if ((*p)->ino != ino)
84 continue;
85 if ((*p)->minor != minor)
86 continue;
87 if ((*p)->major != major)
88 continue;
89 if (((*p)->mode ^ mode) & S_IFMT)
90 continue;
91 return (*p)->name;
92 }
93 q = kmalloc(sizeof(struct hash), GFP_KERNEL);
94 if (!q)
95 panic_show_mem("can't allocate link hash entry");
96 q->major = major;
97 q->minor = minor;
98 q->ino = ino;
99 q->mode = mode;
100 strcpy(q->name, name);
101 q->next = NULL;
102 *p = q;
103 return NULL;
104}
105
106static void __init free_hash(void)
107{
108 struct hash **p, *q;
109 for (p = head; p < head + 32; p++) {
110 while (*p) {
111 q = *p;
112 *p = q->next;
113 kfree(q);
114 }
115 }
116}
117
118static long __init do_utime(char *filename, time64_t mtime)
119{
120 struct timespec64 t[2];
121
122 t[0].tv_sec = mtime;
123 t[0].tv_nsec = 0;
124 t[1].tv_sec = mtime;
125 t[1].tv_nsec = 0;
126 return init_utimes(filename, t);
127}
128
129static __initdata LIST_HEAD(dir_list);
130struct dir_entry {
131 struct list_head list;
132 char *name;
133 time64_t mtime;
134};
135
136static void __init dir_add(const char *name, time64_t mtime)
137{
138 struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL);
139 if (!de)
140 panic_show_mem("can't allocate dir_entry buffer");
141 INIT_LIST_HEAD(&de->list);
142 de->name = kstrdup(name, GFP_KERNEL);
143 de->mtime = mtime;
144 list_add(&de->list, &dir_list);
145}
146
147static void __init dir_utime(void)
148{
149 struct dir_entry *de, *tmp;
150 list_for_each_entry_safe(de, tmp, &dir_list, list) {
151 list_del(&de->list);
152 do_utime(de->name, de->mtime);
153 kfree(de->name);
154 kfree(de);
155 }
156}
157
158static __initdata time64_t mtime;
159
160
161
162static __initdata unsigned long ino, major, minor, nlink;
163static __initdata umode_t mode;
164static __initdata unsigned long body_len, name_len;
165static __initdata uid_t uid;
166static __initdata gid_t gid;
167static __initdata unsigned rdev;
168
169static void __init parse_header(char *s)
170{
171 unsigned long parsed[12];
172 char buf[9];
173 int i;
174
175 buf[8] = '\0';
176 for (i = 0, s += 6; i < 12; i++, s += 8) {
177 memcpy(buf, s, 8);
178 parsed[i] = simple_strtoul(buf, NULL, 16);
179 }
180 ino = parsed[0];
181 mode = parsed[1];
182 uid = parsed[2];
183 gid = parsed[3];
184 nlink = parsed[4];
185 mtime = parsed[5];
186 body_len = parsed[6];
187 major = parsed[7];
188 minor = parsed[8];
189 rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
190 name_len = parsed[11];
191}
192
193
194
195static __initdata enum state {
196 Start,
197 Collect,
198 GotHeader,
199 SkipIt,
200 GotName,
201 CopyFile,
202 GotSymlink,
203 Reset
204} state, next_state;
205
206static __initdata char *victim;
207static unsigned long byte_count __initdata;
208static __initdata loff_t this_header, next_header;
209
210static inline void __init eat(unsigned n)
211{
212 victim += n;
213 this_header += n;
214 byte_count -= n;
215}
216
217static __initdata char *collected;
218static long remains __initdata;
219static __initdata char *collect;
220
221static void __init read_into(char *buf, unsigned size, enum state next)
222{
223 if (byte_count >= size) {
224 collected = victim;
225 eat(size);
226 state = next;
227 } else {
228 collect = collected = buf;
229 remains = size;
230 next_state = next;
231 state = Collect;
232 }
233}
234
235static __initdata char *header_buf, *symlink_buf, *name_buf;
236
237static int __init do_start(void)
238{
239 read_into(header_buf, 110, GotHeader);
240 return 0;
241}
242
243static int __init do_collect(void)
244{
245 unsigned long n = remains;
246 if (byte_count < n)
247 n = byte_count;
248 memcpy(collect, victim, n);
249 eat(n);
250 collect += n;
251 if ((remains -= n) != 0)
252 return 1;
253 state = next_state;
254 return 0;
255}
256
257static int __init do_header(void)
258{
259 if (memcmp(collected, "070707", 6)==0) {
260 error("incorrect cpio method used: use -H newc option");
261 return 1;
262 }
263 if (memcmp(collected, "070701", 6)) {
264 error("no cpio magic");
265 return 1;
266 }
267 parse_header(collected);
268 next_header = this_header + N_ALIGN(name_len) + body_len;
269 next_header = (next_header + 3) & ~3;
270 state = SkipIt;
271 if (name_len <= 0 || name_len > PATH_MAX)
272 return 0;
273 if (S_ISLNK(mode)) {
274 if (body_len > PATH_MAX)
275 return 0;
276 collect = collected = symlink_buf;
277 remains = N_ALIGN(name_len) + body_len;
278 next_state = GotSymlink;
279 state = Collect;
280 return 0;
281 }
282 if (S_ISREG(mode) || !body_len)
283 read_into(name_buf, N_ALIGN(name_len), GotName);
284 return 0;
285}
286
287static int __init do_skip(void)
288{
289 if (this_header + byte_count < next_header) {
290 eat(byte_count);
291 return 1;
292 } else {
293 eat(next_header - this_header);
294 state = next_state;
295 return 0;
296 }
297}
298
299static int __init do_reset(void)
300{
301 while (byte_count && *victim == '\0')
302 eat(1);
303 if (byte_count && (this_header & 3))
304 error("broken padding");
305 return 1;
306}
307
308static void __init clean_path(char *path, umode_t fmode)
309{
310 struct kstat st;
311
312 if (!init_stat(path, &st, AT_SYMLINK_NOFOLLOW) &&
313 (st.mode ^ fmode) & S_IFMT) {
314 if (S_ISDIR(st.mode))
315 init_rmdir(path);
316 else
317 init_unlink(path);
318 }
319}
320
321static int __init maybe_link(void)
322{
323 if (nlink >= 2) {
324 char *old = find_link(major, minor, ino, mode, collected);
325 if (old) {
326 clean_path(collected, 0);
327 return (init_link(old, collected) < 0) ? -1 : 1;
328 }
329 }
330 return 0;
331}
332
333static __initdata struct file *wfile;
334static __initdata loff_t wfile_pos;
335
336static int __init do_name(void)
337{
338 state = SkipIt;
339 next_state = Reset;
340 if (strcmp(collected, "TRAILER!!!") == 0) {
341 free_hash();
342 return 0;
343 }
344 clean_path(collected, mode);
345 if (S_ISREG(mode)) {
346 int ml = maybe_link();
347 if (ml >= 0) {
348 int openflags = O_WRONLY|O_CREAT;
349 if (ml != 1)
350 openflags |= O_TRUNC;
351 wfile = filp_open(collected, openflags, mode);
352 if (IS_ERR(wfile))
353 return 0;
354 wfile_pos = 0;
355
356 vfs_fchown(wfile, uid, gid);
357 vfs_fchmod(wfile, mode);
358 if (body_len)
359 vfs_truncate(&wfile->f_path, body_len);
360 state = CopyFile;
361 }
362 } else if (S_ISDIR(mode)) {
363 init_mkdir(collected, mode);
364 init_chown(collected, uid, gid, 0);
365 init_chmod(collected, mode);
366 dir_add(collected, mtime);
367 } else if (S_ISBLK(mode) || S_ISCHR(mode) ||
368 S_ISFIFO(mode) || S_ISSOCK(mode)) {
369 if (maybe_link() == 0) {
370 init_mknod(collected, mode, rdev);
371 init_chown(collected, uid, gid, 0);
372 init_chmod(collected, mode);
373 do_utime(collected, mtime);
374 }
375 }
376 return 0;
377}
378
379static int __init do_copy(void)
380{
381 if (byte_count >= body_len) {
382 struct timespec64 t[2] = { };
383 if (xwrite(wfile, victim, body_len, &wfile_pos) != body_len)
384 error("write error");
385
386 t[0].tv_sec = mtime;
387 t[1].tv_sec = mtime;
388 vfs_utimes(&wfile->f_path, t);
389
390 fput(wfile);
391 eat(body_len);
392 state = SkipIt;
393 return 0;
394 } else {
395 if (xwrite(wfile, victim, byte_count, &wfile_pos) != byte_count)
396 error("write error");
397 body_len -= byte_count;
398 eat(byte_count);
399 return 1;
400 }
401}
402
403static int __init do_symlink(void)
404{
405 collected[N_ALIGN(name_len) + body_len] = '\0';
406 clean_path(collected, 0);
407 init_symlink(collected + N_ALIGN(name_len), collected);
408 init_chown(collected, uid, gid, AT_SYMLINK_NOFOLLOW);
409 do_utime(collected, mtime);
410 state = SkipIt;
411 next_state = Reset;
412 return 0;
413}
414
415static __initdata int (*actions[])(void) = {
416 [Start] = do_start,
417 [Collect] = do_collect,
418 [GotHeader] = do_header,
419 [SkipIt] = do_skip,
420 [GotName] = do_name,
421 [CopyFile] = do_copy,
422 [GotSymlink] = do_symlink,
423 [Reset] = do_reset,
424};
425
426static long __init write_buffer(char *buf, unsigned long len)
427{
428 byte_count = len;
429 victim = buf;
430
431 while (!actions[state]())
432 ;
433 return len - byte_count;
434}
435
436static long __init flush_buffer(void *bufv, unsigned long len)
437{
438 char *buf = (char *) bufv;
439 long written;
440 long origLen = len;
441 if (message)
442 return -1;
443 while ((written = write_buffer(buf, len)) < len && !message) {
444 char c = buf[written];
445 if (c == '0') {
446 buf += written;
447 len -= written;
448 state = Start;
449 } else if (c == 0) {
450 buf += written;
451 len -= written;
452 state = Reset;
453 } else
454 error("junk within compressed archive");
455 }
456 return origLen;
457}
458
459static unsigned long my_inptr;
460
461#include <linux/decompress/generic.h>
462
463static char * __init unpack_to_rootfs(char *buf, unsigned long len)
464{
465 long written;
466 decompress_fn decompress;
467 const char *compress_name;
468 static __initdata char msg_buf[64];
469
470 header_buf = kmalloc(110, GFP_KERNEL);
471 symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
472 name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
473
474 if (!header_buf || !symlink_buf || !name_buf)
475 panic_show_mem("can't allocate buffers");
476
477 state = Start;
478 this_header = 0;
479 message = NULL;
480 while (!message && len) {
481 loff_t saved_offset = this_header;
482 if (*buf == '0' && !(this_header & 3)) {
483 state = Start;
484 written = write_buffer(buf, len);
485 buf += written;
486 len -= written;
487 continue;
488 }
489 if (!*buf) {
490 buf++;
491 len--;
492 this_header++;
493 continue;
494 }
495 this_header = 0;
496 decompress = decompress_method(buf, len, &compress_name);
497 pr_debug("Detected %s compressed data\n", compress_name);
498 if (decompress) {
499 int res = decompress(buf, len, NULL, flush_buffer, NULL,
500 &my_inptr, error);
501 if (res)
502 error("decompressor failed");
503 } else if (compress_name) {
504 if (!message) {
505 snprintf(msg_buf, sizeof msg_buf,
506 "compression method %s not configured",
507 compress_name);
508 message = msg_buf;
509 }
510 } else
511 error("invalid magic at start of compressed archive");
512 if (state != Reset)
513 error("junk at the end of compressed archive");
514 this_header = saved_offset + my_inptr;
515 buf += my_inptr;
516 len -= my_inptr;
517 }
518 dir_utime();
519 kfree(name_buf);
520 kfree(symlink_buf);
521 kfree(header_buf);
522 return message;
523}
524
525static int __initdata do_retain_initrd;
526
527static int __init retain_initrd_param(char *str)
528{
529 if (*str)
530 return 0;
531 do_retain_initrd = 1;
532 return 1;
533}
534__setup("retain_initrd", retain_initrd_param);
535
536#ifdef CONFIG_ARCH_HAS_KEEPINITRD
537static int __init keepinitrd_setup(char *__unused)
538{
539 do_retain_initrd = 1;
540 return 1;
541}
542__setup("keepinitrd", keepinitrd_setup);
543#endif
544
545static bool __initdata initramfs_async = true;
546static int __init initramfs_async_setup(char *str)
547{
548 strtobool(str, &initramfs_async);
549 return 1;
550}
551__setup("initramfs_async=", initramfs_async_setup);
552
553extern char __initramfs_start[];
554extern unsigned long __initramfs_size;
555#include <linux/initrd.h>
556#include <linux/kexec.h>
557
558void __init reserve_initrd_mem(void)
559{
560 phys_addr_t start;
561 unsigned long size;
562
563
564 initrd_start = initrd_end = 0;
565
566 if (!phys_initrd_size)
567 return;
568
569
570
571
572
573
574 start = round_down(phys_initrd_start, PAGE_SIZE);
575 size = phys_initrd_size + (phys_initrd_start - start);
576 size = round_up(size, PAGE_SIZE);
577
578 if (!memblock_is_region_memory(start, size)) {
579 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
580 (u64)start, size);
581 goto disable;
582 }
583
584 if (memblock_is_region_reserved(start, size)) {
585 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
586 (u64)start, size);
587 goto disable;
588 }
589
590 memblock_reserve(start, size);
591
592 initrd_start = (unsigned long)__va(phys_initrd_start);
593 initrd_end = initrd_start + phys_initrd_size;
594 initrd_below_start_ok = 1;
595
596 return;
597disable:
598 pr_cont(" - disabling initrd\n");
599 initrd_start = 0;
600 initrd_end = 0;
601}
602
603void __weak __init free_initrd_mem(unsigned long start, unsigned long end)
604{
605#ifdef CONFIG_ARCH_KEEP_MEMBLOCK
606 unsigned long aligned_start = ALIGN_DOWN(start, PAGE_SIZE);
607 unsigned long aligned_end = ALIGN(end, PAGE_SIZE);
608
609 memblock_free(__pa(aligned_start), aligned_end - aligned_start);
610#endif
611
612 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
613 "initrd");
614}
615
616#ifdef CONFIG_KEXEC_CORE
617static bool __init kexec_free_initrd(void)
618{
619 unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
620 unsigned long crashk_end = (unsigned long)__va(crashk_res.end);
621
622
623
624
625
626 if (initrd_start >= crashk_end || initrd_end <= crashk_start)
627 return false;
628
629
630
631
632 memset((void *)initrd_start, 0, initrd_end - initrd_start);
633 if (initrd_start < crashk_start)
634 free_initrd_mem(initrd_start, crashk_start);
635 if (initrd_end > crashk_end)
636 free_initrd_mem(crashk_end, initrd_end);
637 return true;
638}
639#else
640static inline bool kexec_free_initrd(void)
641{
642 return false;
643}
644#endif
645
646#ifdef CONFIG_BLK_DEV_RAM
647static void __init populate_initrd_image(char *err)
648{
649 ssize_t written;
650 struct file *file;
651 loff_t pos = 0;
652
653 unpack_to_rootfs(__initramfs_start, __initramfs_size);
654
655 printk(KERN_INFO "rootfs image is not initramfs (%s); looks like an initrd\n",
656 err);
657 file = filp_open("/initrd.image", O_WRONLY | O_CREAT, 0700);
658 if (IS_ERR(file))
659 return;
660
661 written = xwrite(file, (char *)initrd_start, initrd_end - initrd_start,
662 &pos);
663 if (written != initrd_end - initrd_start)
664 pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
665 written, initrd_end - initrd_start);
666 fput(file);
667}
668#endif
669
670static void __init do_populate_rootfs(void *unused, async_cookie_t cookie)
671{
672
673 char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
674 if (err)
675 panic_show_mem("%s", err);
676
677 if (!initrd_start || IS_ENABLED(CONFIG_INITRAMFS_FORCE))
678 goto done;
679
680 if (IS_ENABLED(CONFIG_BLK_DEV_RAM))
681 printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
682 else
683 printk(KERN_INFO "Unpacking initramfs...\n");
684
685 err = unpack_to_rootfs((char *)initrd_start, initrd_end - initrd_start);
686 if (err) {
687#ifdef CONFIG_BLK_DEV_RAM
688 populate_initrd_image(err);
689#else
690 printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
691#endif
692 }
693
694done:
695
696
697
698
699 if (!do_retain_initrd && initrd_start && !kexec_free_initrd())
700 free_initrd_mem(initrd_start, initrd_end);
701 initrd_start = 0;
702 initrd_end = 0;
703
704 flush_delayed_fput();
705}
706
707static ASYNC_DOMAIN_EXCLUSIVE(initramfs_domain);
708static async_cookie_t initramfs_cookie;
709
710void wait_for_initramfs(void)
711{
712 if (!initramfs_cookie) {
713
714
715
716
717
718
719 pr_warn_once("wait_for_initramfs() called before rootfs_initcalls\n");
720 return;
721 }
722 async_synchronize_cookie_domain(initramfs_cookie + 1, &initramfs_domain);
723}
724EXPORT_SYMBOL_GPL(wait_for_initramfs);
725
726static int __init populate_rootfs(void)
727{
728 initramfs_cookie = async_schedule_domain(do_populate_rootfs, NULL,
729 &initramfs_domain);
730 if (!initramfs_async)
731 wait_for_initramfs();
732 return 0;
733}
734rootfs_initcall(populate_rootfs);
735
