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v3.1
 
  1#include <linux/init.h>
  2#include <linux/fs.h>
  3#include <linux/slab.h>
  4#include <linux/types.h>
  5#include <linux/fcntl.h>
  6#include <linux/delay.h>
  7#include <linux/string.h>
  8#include <linux/dirent.h>
  9#include <linux/syscalls.h>
 10#include <linux/utime.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 11
 12static __initdata char *message;
 13static void __init error(char *x)
 14{
 15	if (!message)
 16		message = x;
 17}
 18
 19/* link hash */
 20
 21#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
 22
 23static __initdata struct hash {
 24	int ino, minor, major;
 25	mode_t mode;
 26	struct hash *next;
 27	char name[N_ALIGN(PATH_MAX)];
 28} *head[32];
 29
 30static inline int hash(int major, int minor, int ino)
 31{
 32	unsigned long tmp = ino + minor + (major << 3);
 33	tmp += tmp >> 5;
 34	return tmp & 31;
 35}
 36
 37static char __init *find_link(int major, int minor, int ino,
 38			      mode_t mode, char *name)
 39{
 40	struct hash **p, *q;
 41	for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
 42		if ((*p)->ino != ino)
 43			continue;
 44		if ((*p)->minor != minor)
 45			continue;
 46		if ((*p)->major != major)
 47			continue;
 48		if (((*p)->mode ^ mode) & S_IFMT)
 49			continue;
 50		return (*p)->name;
 51	}
 52	q = kmalloc(sizeof(struct hash), GFP_KERNEL);
 53	if (!q)
 54		panic("can't allocate link hash entry");
 55	q->major = major;
 56	q->minor = minor;
 57	q->ino = ino;
 58	q->mode = mode;
 59	strcpy(q->name, name);
 60	q->next = NULL;
 61	*p = q;
 62	return NULL;
 63}
 64
 65static void __init free_hash(void)
 66{
 67	struct hash **p, *q;
 68	for (p = head; p < head + 32; p++) {
 69		while (*p) {
 70			q = *p;
 71			*p = q->next;
 72			kfree(q);
 73		}
 74	}
 75}
 76
 77static long __init do_utime(char __user *filename, time_t mtime)
 78{
 79	struct timespec t[2];
 80
 81	t[0].tv_sec = mtime;
 82	t[0].tv_nsec = 0;
 83	t[1].tv_sec = mtime;
 84	t[1].tv_nsec = 0;
 85
 86	return do_utimes(AT_FDCWD, filename, t, AT_SYMLINK_NOFOLLOW);
 87}
 88
 89static __initdata LIST_HEAD(dir_list);
 90struct dir_entry {
 91	struct list_head list;
 92	char *name;
 93	time_t mtime;
 94};
 95
 96static void __init dir_add(const char *name, time_t mtime)
 97{
 98	struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL);
 99	if (!de)
100		panic("can't allocate dir_entry buffer");
101	INIT_LIST_HEAD(&de->list);
102	de->name = kstrdup(name, GFP_KERNEL);
103	de->mtime = mtime;
104	list_add(&de->list, &dir_list);
105}
106
107static void __init dir_utime(void)
108{
109	struct dir_entry *de, *tmp;
110	list_for_each_entry_safe(de, tmp, &dir_list, list) {
111		list_del(&de->list);
112		do_utime(de->name, de->mtime);
113		kfree(de->name);
114		kfree(de);
115	}
116}
117
118static __initdata time_t mtime;
119
120/* cpio header parsing */
121
122static __initdata unsigned long ino, major, minor, nlink;
123static __initdata mode_t mode;
124static __initdata unsigned long body_len, name_len;
125static __initdata uid_t uid;
126static __initdata gid_t gid;
127static __initdata unsigned rdev;
128
129static void __init parse_header(char *s)
130{
131	unsigned long parsed[12];
132	char buf[9];
133	int i;
134
135	buf[8] = '\0';
136	for (i = 0, s += 6; i < 12; i++, s += 8) {
137		memcpy(buf, s, 8);
138		parsed[i] = simple_strtoul(buf, NULL, 16);
139	}
140	ino = parsed[0];
141	mode = parsed[1];
142	uid = parsed[2];
143	gid = parsed[3];
144	nlink = parsed[4];
145	mtime = parsed[5];
146	body_len = parsed[6];
147	major = parsed[7];
148	minor = parsed[8];
149	rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
150	name_len = parsed[11];
151}
152
153/* FSM */
154
155static __initdata enum state {
156	Start,
157	Collect,
158	GotHeader,
159	SkipIt,
160	GotName,
161	CopyFile,
162	GotSymlink,
163	Reset
164} state, next_state;
165
166static __initdata char *victim;
167static __initdata unsigned count;
168static __initdata loff_t this_header, next_header;
169
170static inline void __init eat(unsigned n)
171{
172	victim += n;
173	this_header += n;
174	count -= n;
175}
176
177static __initdata char *vcollected;
178static __initdata char *collected;
179static __initdata int remains;
180static __initdata char *collect;
181
182static void __init read_into(char *buf, unsigned size, enum state next)
183{
184	if (count >= size) {
185		collected = victim;
186		eat(size);
187		state = next;
188	} else {
189		collect = collected = buf;
190		remains = size;
191		next_state = next;
192		state = Collect;
193	}
194}
195
196static __initdata char *header_buf, *symlink_buf, *name_buf;
197
198static int __init do_start(void)
199{
200	read_into(header_buf, 110, GotHeader);
201	return 0;
202}
203
204static int __init do_collect(void)
205{
206	unsigned n = remains;
207	if (count < n)
208		n = count;
209	memcpy(collect, victim, n);
210	eat(n);
211	collect += n;
212	if ((remains -= n) != 0)
213		return 1;
214	state = next_state;
215	return 0;
216}
217
218static int __init do_header(void)
219{
220	if (memcmp(collected, "070707", 6)==0) {
221		error("incorrect cpio method used: use -H newc option");
222		return 1;
223	}
224	if (memcmp(collected, "070701", 6)) {
225		error("no cpio magic");
226		return 1;
227	}
228	parse_header(collected);
229	next_header = this_header + N_ALIGN(name_len) + body_len;
230	next_header = (next_header + 3) & ~3;
231	state = SkipIt;
232	if (name_len <= 0 || name_len > PATH_MAX)
233		return 0;
234	if (S_ISLNK(mode)) {
235		if (body_len > PATH_MAX)
236			return 0;
237		collect = collected = symlink_buf;
238		remains = N_ALIGN(name_len) + body_len;
239		next_state = GotSymlink;
240		state = Collect;
241		return 0;
242	}
243	if (S_ISREG(mode) || !body_len)
244		read_into(name_buf, N_ALIGN(name_len), GotName);
245	return 0;
246}
247
248static int __init do_skip(void)
249{
250	if (this_header + count < next_header) {
251		eat(count);
252		return 1;
253	} else {
254		eat(next_header - this_header);
255		state = next_state;
256		return 0;
257	}
258}
259
260static int __init do_reset(void)
261{
262	while(count && *victim == '\0')
263		eat(1);
264	if (count && (this_header & 3))
265		error("broken padding");
266	return 1;
267}
268
269static int __init maybe_link(void)
270{
271	if (nlink >= 2) {
272		char *old = find_link(major, minor, ino, mode, collected);
273		if (old)
274			return (sys_link(old, collected) < 0) ? -1 : 1;
 
 
 
275	}
276	return 0;
277}
278
279static void __init clean_path(char *path, mode_t mode)
280{
281	struct stat st;
282
283	if (!sys_newlstat(path, &st) && (st.st_mode^mode) & S_IFMT) {
284		if (S_ISDIR(st.st_mode))
285			sys_rmdir(path);
286		else
287			sys_unlink(path);
288	}
 
289}
290
291static __initdata int wfd;
292
293static int __init do_name(void)
294{
295	state = SkipIt;
296	next_state = Reset;
297	if (strcmp(collected, "TRAILER!!!") == 0) {
298		free_hash();
299		return 0;
300	}
301	clean_path(collected, mode);
302	if (S_ISREG(mode)) {
303		int ml = maybe_link();
304		if (ml >= 0) {
305			int openflags = O_WRONLY|O_CREAT;
306			if (ml != 1)
307				openflags |= O_TRUNC;
308			wfd = sys_open(collected, openflags, mode);
309
310			if (wfd >= 0) {
311				sys_fchown(wfd, uid, gid);
312				sys_fchmod(wfd, mode);
313				if (body_len)
314					sys_ftruncate(wfd, body_len);
315				vcollected = kstrdup(collected, GFP_KERNEL);
316				state = CopyFile;
317			}
318		}
319	} else if (S_ISDIR(mode)) {
320		sys_mkdir(collected, mode);
321		sys_chown(collected, uid, gid);
322		sys_chmod(collected, mode);
323		dir_add(collected, mtime);
324	} else if (S_ISBLK(mode) || S_ISCHR(mode) ||
325		   S_ISFIFO(mode) || S_ISSOCK(mode)) {
326		if (maybe_link() == 0) {
327			sys_mknod(collected, mode, rdev);
328			sys_chown(collected, uid, gid);
329			sys_chmod(collected, mode);
330			do_utime(collected, mtime);
331		}
332	}
333	return 0;
334}
335
336static int __init do_copy(void)
337{
338	if (count >= body_len) {
339		sys_write(wfd, victim, body_len);
340		sys_close(wfd);
 
341		do_utime(vcollected, mtime);
342		kfree(vcollected);
343		eat(body_len);
344		state = SkipIt;
345		return 0;
346	} else {
347		sys_write(wfd, victim, count);
348		body_len -= count;
349		eat(count);
 
350		return 1;
351	}
352}
353
354static int __init do_symlink(void)
355{
356	collected[N_ALIGN(name_len) + body_len] = '\0';
357	clean_path(collected, 0);
358	sys_symlink(collected + N_ALIGN(name_len), collected);
359	sys_lchown(collected, uid, gid);
360	do_utime(collected, mtime);
361	state = SkipIt;
362	next_state = Reset;
363	return 0;
364}
365
366static __initdata int (*actions[])(void) = {
367	[Start]		= do_start,
368	[Collect]	= do_collect,
369	[GotHeader]	= do_header,
370	[SkipIt]	= do_skip,
371	[GotName]	= do_name,
372	[CopyFile]	= do_copy,
373	[GotSymlink]	= do_symlink,
374	[Reset]		= do_reset,
375};
376
377static int __init write_buffer(char *buf, unsigned len)
378{
379	count = len;
380	victim = buf;
381
382	while (!actions[state]())
383		;
384	return len - count;
385}
386
387static int __init flush_buffer(void *bufv, unsigned len)
388{
389	char *buf = (char *) bufv;
390	int written;
391	int origLen = len;
392	if (message)
393		return -1;
394	while ((written = write_buffer(buf, len)) < len && !message) {
395		char c = buf[written];
396		if (c == '0') {
397			buf += written;
398			len -= written;
399			state = Start;
400		} else if (c == 0) {
401			buf += written;
402			len -= written;
403			state = Reset;
404		} else
405			error("junk in compressed archive");
406	}
407	return origLen;
408}
409
410static unsigned my_inptr;   /* index of next byte to be processed in inbuf */
411
412#include <linux/decompress/generic.h>
413
414static char * __init unpack_to_rootfs(char *buf, unsigned len)
415{
416	int written, res;
417	decompress_fn decompress;
418	const char *compress_name;
419	static __initdata char msg_buf[64];
420
421	header_buf = kmalloc(110, GFP_KERNEL);
422	symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
423	name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
424
425	if (!header_buf || !symlink_buf || !name_buf)
426		panic("can't allocate buffers");
427
428	state = Start;
429	this_header = 0;
430	message = NULL;
431	while (!message && len) {
432		loff_t saved_offset = this_header;
433		if (*buf == '0' && !(this_header & 3)) {
434			state = Start;
435			written = write_buffer(buf, len);
436			buf += written;
437			len -= written;
438			continue;
439		}
440		if (!*buf) {
441			buf++;
442			len--;
443			this_header++;
444			continue;
445		}
446		this_header = 0;
447		decompress = decompress_method(buf, len, &compress_name);
 
448		if (decompress) {
449			res = decompress(buf, len, NULL, flush_buffer, NULL,
450				   &my_inptr, error);
451			if (res)
452				error("decompressor failed");
453		} else if (compress_name) {
454			if (!message) {
455				snprintf(msg_buf, sizeof msg_buf,
456					 "compression method %s not configured",
457					 compress_name);
458				message = msg_buf;
459			}
460		} else
461			error("junk in compressed archive");
462		if (state != Reset)
463			error("junk in compressed archive");
464		this_header = saved_offset + my_inptr;
465		buf += my_inptr;
466		len -= my_inptr;
467	}
468	dir_utime();
469	kfree(name_buf);
470	kfree(symlink_buf);
471	kfree(header_buf);
472	return message;
473}
474
475static int __initdata do_retain_initrd;
476
477static int __init retain_initrd_param(char *str)
478{
479	if (*str)
480		return 0;
481	do_retain_initrd = 1;
482	return 1;
483}
484__setup("retain_initrd", retain_initrd_param);
485
 
 
 
 
 
 
 
 
 
486extern char __initramfs_start[];
487extern unsigned long __initramfs_size;
488#include <linux/initrd.h>
489#include <linux/kexec.h>
490
491static void __init free_initrd(void)
 
 
 
 
 
 
 
492{
493#ifdef CONFIG_KEXEC
494	unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
495	unsigned long crashk_end   = (unsigned long)__va(crashk_res.end);
496#endif
497	if (do_retain_initrd)
498		goto skip;
499
500#ifdef CONFIG_KEXEC
501	/*
502	 * If the initrd region is overlapped with crashkernel reserved region,
503	 * free only memory that is not part of crashkernel region.
504	 */
505	if (initrd_start < crashk_end && initrd_end > crashk_start) {
506		/*
507		 * Initialize initrd memory region since the kexec boot does
508		 * not do.
509		 */
510		memset((void *)initrd_start, 0, initrd_end - initrd_start);
511		if (initrd_start < crashk_start)
512			free_initrd_mem(initrd_start, crashk_start);
513		if (initrd_end > crashk_end)
514			free_initrd_mem(crashk_end, initrd_end);
515	} else
516#endif
517		free_initrd_mem(initrd_start, initrd_end);
518skip:
519	initrd_start = 0;
520	initrd_end = 0;
521}
 
 
 
 
 
 
522
523#ifdef CONFIG_BLK_DEV_RAM
524#define BUF_SIZE 1024
525static void __init clean_rootfs(void)
526{
527	int fd;
528	void *buf;
529	struct linux_dirent64 *dirp;
530	int num;
531
532	fd = sys_open((const char __user __force *) "/", O_RDONLY, 0);
533	WARN_ON(fd < 0);
534	if (fd < 0)
535		return;
536	buf = kzalloc(BUF_SIZE, GFP_KERNEL);
537	WARN_ON(!buf);
538	if (!buf) {
539		sys_close(fd);
540		return;
541	}
542
543	dirp = buf;
544	num = sys_getdents64(fd, dirp, BUF_SIZE);
545	while (num > 0) {
546		while (num > 0) {
547			struct stat st;
548			int ret;
549
550			ret = sys_newlstat(dirp->d_name, &st);
551			WARN_ON_ONCE(ret);
552			if (!ret) {
553				if (S_ISDIR(st.st_mode))
554					sys_rmdir(dirp->d_name);
555				else
556					sys_unlink(dirp->d_name);
557			}
558
559			num -= dirp->d_reclen;
560			dirp = (void *)dirp + dirp->d_reclen;
561		}
562		dirp = buf;
563		memset(buf, 0, BUF_SIZE);
564		num = sys_getdents64(fd, dirp, BUF_SIZE);
565	}
566
567	sys_close(fd);
568	kfree(buf);
569}
570#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
571
572static int __init populate_rootfs(void)
573{
 
574	char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
575	if (err)
576		panic(err);	/* Failed to decompress INTERNAL initramfs */
577	if (initrd_start) {
578#ifdef CONFIG_BLK_DEV_RAM
579		int fd;
 
 
580		printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
581		err = unpack_to_rootfs((char *)initrd_start,
582			initrd_end - initrd_start);
583		if (!err) {
584			free_initrd();
585			return 0;
586		} else {
587			clean_rootfs();
588			unpack_to_rootfs(__initramfs_start, __initramfs_size);
589		}
590		printk(KERN_INFO "rootfs image is not initramfs (%s)"
591				"; looks like an initrd\n", err);
592		fd = sys_open((const char __user __force *) "/initrd.image",
593			      O_WRONLY|O_CREAT, 0700);
594		if (fd >= 0) {
595			sys_write(fd, (char *)initrd_start,
596					initrd_end - initrd_start);
597			sys_close(fd);
598			free_initrd();
599		}
600#else
601		printk(KERN_INFO "Unpacking initramfs...\n");
602		err = unpack_to_rootfs((char *)initrd_start,
603			initrd_end - initrd_start);
604		if (err)
605			printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
606		free_initrd();
607#endif
608	}
 
 
 
 
 
 
 
 
 
 
 
 
609	return 0;
610}
611rootfs_initcall(populate_rootfs);
v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/init.h>
  3#include <linux/fs.h>
  4#include <linux/slab.h>
  5#include <linux/types.h>
  6#include <linux/fcntl.h>
  7#include <linux/delay.h>
  8#include <linux/string.h>
  9#include <linux/dirent.h>
 10#include <linux/syscalls.h>
 11#include <linux/utime.h>
 12#include <linux/file.h>
 13
 14static ssize_t __init xwrite(int fd, const char *p, size_t count)
 15{
 16	ssize_t out = 0;
 17
 18	/* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */
 19	while (count) {
 20		ssize_t rv = ksys_write(fd, p, count);
 21
 22		if (rv < 0) {
 23			if (rv == -EINTR || rv == -EAGAIN)
 24				continue;
 25			return out ? out : rv;
 26		} else if (rv == 0)
 27			break;
 28
 29		p += rv;
 30		out += rv;
 31		count -= rv;
 32	}
 33
 34	return out;
 35}
 36
 37static __initdata char *message;
 38static void __init error(char *x)
 39{
 40	if (!message)
 41		message = x;
 42}
 43
 44/* link hash */
 45
 46#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
 47
 48static __initdata struct hash {
 49	int ino, minor, major;
 50	umode_t mode;
 51	struct hash *next;
 52	char name[N_ALIGN(PATH_MAX)];
 53} *head[32];
 54
 55static inline int hash(int major, int minor, int ino)
 56{
 57	unsigned long tmp = ino + minor + (major << 3);
 58	tmp += tmp >> 5;
 59	return tmp & 31;
 60}
 61
 62static char __init *find_link(int major, int minor, int ino,
 63			      umode_t mode, char *name)
 64{
 65	struct hash **p, *q;
 66	for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
 67		if ((*p)->ino != ino)
 68			continue;
 69		if ((*p)->minor != minor)
 70			continue;
 71		if ((*p)->major != major)
 72			continue;
 73		if (((*p)->mode ^ mode) & S_IFMT)
 74			continue;
 75		return (*p)->name;
 76	}
 77	q = kmalloc(sizeof(struct hash), GFP_KERNEL);
 78	if (!q)
 79		panic("can't allocate link hash entry");
 80	q->major = major;
 81	q->minor = minor;
 82	q->ino = ino;
 83	q->mode = mode;
 84	strcpy(q->name, name);
 85	q->next = NULL;
 86	*p = q;
 87	return NULL;
 88}
 89
 90static void __init free_hash(void)
 91{
 92	struct hash **p, *q;
 93	for (p = head; p < head + 32; p++) {
 94		while (*p) {
 95			q = *p;
 96			*p = q->next;
 97			kfree(q);
 98		}
 99	}
100}
101
102static long __init do_utime(char *filename, time64_t mtime)
103{
104	struct timespec64 t[2];
105
106	t[0].tv_sec = mtime;
107	t[0].tv_nsec = 0;
108	t[1].tv_sec = mtime;
109	t[1].tv_nsec = 0;
110
111	return do_utimes(AT_FDCWD, filename, t, AT_SYMLINK_NOFOLLOW);
112}
113
114static __initdata LIST_HEAD(dir_list);
115struct dir_entry {
116	struct list_head list;
117	char *name;
118	time64_t mtime;
119};
120
121static void __init dir_add(const char *name, time64_t mtime)
122{
123	struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL);
124	if (!de)
125		panic("can't allocate dir_entry buffer");
126	INIT_LIST_HEAD(&de->list);
127	de->name = kstrdup(name, GFP_KERNEL);
128	de->mtime = mtime;
129	list_add(&de->list, &dir_list);
130}
131
132static void __init dir_utime(void)
133{
134	struct dir_entry *de, *tmp;
135	list_for_each_entry_safe(de, tmp, &dir_list, list) {
136		list_del(&de->list);
137		do_utime(de->name, de->mtime);
138		kfree(de->name);
139		kfree(de);
140	}
141}
142
143static __initdata time64_t mtime;
144
145/* cpio header parsing */
146
147static __initdata unsigned long ino, major, minor, nlink;
148static __initdata umode_t mode;
149static __initdata unsigned long body_len, name_len;
150static __initdata uid_t uid;
151static __initdata gid_t gid;
152static __initdata unsigned rdev;
153
154static void __init parse_header(char *s)
155{
156	unsigned long parsed[12];
157	char buf[9];
158	int i;
159
160	buf[8] = '\0';
161	for (i = 0, s += 6; i < 12; i++, s += 8) {
162		memcpy(buf, s, 8);
163		parsed[i] = simple_strtoul(buf, NULL, 16);
164	}
165	ino = parsed[0];
166	mode = parsed[1];
167	uid = parsed[2];
168	gid = parsed[3];
169	nlink = parsed[4];
170	mtime = parsed[5]; /* breaks in y2106 */
171	body_len = parsed[6];
172	major = parsed[7];
173	minor = parsed[8];
174	rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
175	name_len = parsed[11];
176}
177
178/* FSM */
179
180static __initdata enum state {
181	Start,
182	Collect,
183	GotHeader,
184	SkipIt,
185	GotName,
186	CopyFile,
187	GotSymlink,
188	Reset
189} state, next_state;
190
191static __initdata char *victim;
192static unsigned long byte_count __initdata;
193static __initdata loff_t this_header, next_header;
194
195static inline void __init eat(unsigned n)
196{
197	victim += n;
198	this_header += n;
199	byte_count -= n;
200}
201
202static __initdata char *vcollected;
203static __initdata char *collected;
204static long remains __initdata;
205static __initdata char *collect;
206
207static void __init read_into(char *buf, unsigned size, enum state next)
208{
209	if (byte_count >= size) {
210		collected = victim;
211		eat(size);
212		state = next;
213	} else {
214		collect = collected = buf;
215		remains = size;
216		next_state = next;
217		state = Collect;
218	}
219}
220
221static __initdata char *header_buf, *symlink_buf, *name_buf;
222
223static int __init do_start(void)
224{
225	read_into(header_buf, 110, GotHeader);
226	return 0;
227}
228
229static int __init do_collect(void)
230{
231	unsigned long n = remains;
232	if (byte_count < n)
233		n = byte_count;
234	memcpy(collect, victim, n);
235	eat(n);
236	collect += n;
237	if ((remains -= n) != 0)
238		return 1;
239	state = next_state;
240	return 0;
241}
242
243static int __init do_header(void)
244{
245	if (memcmp(collected, "070707", 6)==0) {
246		error("incorrect cpio method used: use -H newc option");
247		return 1;
248	}
249	if (memcmp(collected, "070701", 6)) {
250		error("no cpio magic");
251		return 1;
252	}
253	parse_header(collected);
254	next_header = this_header + N_ALIGN(name_len) + body_len;
255	next_header = (next_header + 3) & ~3;
256	state = SkipIt;
257	if (name_len <= 0 || name_len > PATH_MAX)
258		return 0;
259	if (S_ISLNK(mode)) {
260		if (body_len > PATH_MAX)
261			return 0;
262		collect = collected = symlink_buf;
263		remains = N_ALIGN(name_len) + body_len;
264		next_state = GotSymlink;
265		state = Collect;
266		return 0;
267	}
268	if (S_ISREG(mode) || !body_len)
269		read_into(name_buf, N_ALIGN(name_len), GotName);
270	return 0;
271}
272
273static int __init do_skip(void)
274{
275	if (this_header + byte_count < next_header) {
276		eat(byte_count);
277		return 1;
278	} else {
279		eat(next_header - this_header);
280		state = next_state;
281		return 0;
282	}
283}
284
285static int __init do_reset(void)
286{
287	while (byte_count && *victim == '\0')
288		eat(1);
289	if (byte_count && (this_header & 3))
290		error("broken padding");
291	return 1;
292}
293
294static void __init clean_path(char *path, umode_t fmode)
295{
296	struct kstat st;
297
298	if (!vfs_lstat(path, &st) && (st.mode ^ fmode) & S_IFMT) {
299		if (S_ISDIR(st.mode))
300			ksys_rmdir(path);
301		else
302			ksys_unlink(path);
303	}
 
304}
305
306static int __init maybe_link(void)
307{
308	if (nlink >= 2) {
309		char *old = find_link(major, minor, ino, mode, collected);
310		if (old) {
311			clean_path(collected, 0);
312			return (ksys_link(old, collected) < 0) ? -1 : 1;
313		}
 
314	}
315	return 0;
316}
317
318static __initdata int wfd;
319
320static int __init do_name(void)
321{
322	state = SkipIt;
323	next_state = Reset;
324	if (strcmp(collected, "TRAILER!!!") == 0) {
325		free_hash();
326		return 0;
327	}
328	clean_path(collected, mode);
329	if (S_ISREG(mode)) {
330		int ml = maybe_link();
331		if (ml >= 0) {
332			int openflags = O_WRONLY|O_CREAT;
333			if (ml != 1)
334				openflags |= O_TRUNC;
335			wfd = ksys_open(collected, openflags, mode);
336
337			if (wfd >= 0) {
338				ksys_fchown(wfd, uid, gid);
339				ksys_fchmod(wfd, mode);
340				if (body_len)
341					ksys_ftruncate(wfd, body_len);
342				vcollected = kstrdup(collected, GFP_KERNEL);
343				state = CopyFile;
344			}
345		}
346	} else if (S_ISDIR(mode)) {
347		ksys_mkdir(collected, mode);
348		ksys_chown(collected, uid, gid);
349		ksys_chmod(collected, mode);
350		dir_add(collected, mtime);
351	} else if (S_ISBLK(mode) || S_ISCHR(mode) ||
352		   S_ISFIFO(mode) || S_ISSOCK(mode)) {
353		if (maybe_link() == 0) {
354			ksys_mknod(collected, mode, rdev);
355			ksys_chown(collected, uid, gid);
356			ksys_chmod(collected, mode);
357			do_utime(collected, mtime);
358		}
359	}
360	return 0;
361}
362
363static int __init do_copy(void)
364{
365	if (byte_count >= body_len) {
366		if (xwrite(wfd, victim, body_len) != body_len)
367			error("write error");
368		ksys_close(wfd);
369		do_utime(vcollected, mtime);
370		kfree(vcollected);
371		eat(body_len);
372		state = SkipIt;
373		return 0;
374	} else {
375		if (xwrite(wfd, victim, byte_count) != byte_count)
376			error("write error");
377		body_len -= byte_count;
378		eat(byte_count);
379		return 1;
380	}
381}
382
383static int __init do_symlink(void)
384{
385	collected[N_ALIGN(name_len) + body_len] = '\0';
386	clean_path(collected, 0);
387	ksys_symlink(collected + N_ALIGN(name_len), collected);
388	ksys_lchown(collected, uid, gid);
389	do_utime(collected, mtime);
390	state = SkipIt;
391	next_state = Reset;
392	return 0;
393}
394
395static __initdata int (*actions[])(void) = {
396	[Start]		= do_start,
397	[Collect]	= do_collect,
398	[GotHeader]	= do_header,
399	[SkipIt]	= do_skip,
400	[GotName]	= do_name,
401	[CopyFile]	= do_copy,
402	[GotSymlink]	= do_symlink,
403	[Reset]		= do_reset,
404};
405
406static long __init write_buffer(char *buf, unsigned long len)
407{
408	byte_count = len;
409	victim = buf;
410
411	while (!actions[state]())
412		;
413	return len - byte_count;
414}
415
416static long __init flush_buffer(void *bufv, unsigned long len)
417{
418	char *buf = (char *) bufv;
419	long written;
420	long origLen = len;
421	if (message)
422		return -1;
423	while ((written = write_buffer(buf, len)) < len && !message) {
424		char c = buf[written];
425		if (c == '0') {
426			buf += written;
427			len -= written;
428			state = Start;
429		} else if (c == 0) {
430			buf += written;
431			len -= written;
432			state = Reset;
433		} else
434			error("junk within compressed archive");
435	}
436	return origLen;
437}
438
439static unsigned long my_inptr; /* index of next byte to be processed in inbuf */
440
441#include <linux/decompress/generic.h>
442
443static char * __init unpack_to_rootfs(char *buf, unsigned long len)
444{
445	long written;
446	decompress_fn decompress;
447	const char *compress_name;
448	static __initdata char msg_buf[64];
449
450	header_buf = kmalloc(110, GFP_KERNEL);
451	symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
452	name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
453
454	if (!header_buf || !symlink_buf || !name_buf)
455		panic("can't allocate buffers");
456
457	state = Start;
458	this_header = 0;
459	message = NULL;
460	while (!message && len) {
461		loff_t saved_offset = this_header;
462		if (*buf == '0' && !(this_header & 3)) {
463			state = Start;
464			written = write_buffer(buf, len);
465			buf += written;
466			len -= written;
467			continue;
468		}
469		if (!*buf) {
470			buf++;
471			len--;
472			this_header++;
473			continue;
474		}
475		this_header = 0;
476		decompress = decompress_method(buf, len, &compress_name);
477		pr_debug("Detected %s compressed data\n", compress_name);
478		if (decompress) {
479			int res = decompress(buf, len, NULL, flush_buffer, NULL,
480				   &my_inptr, error);
481			if (res)
482				error("decompressor failed");
483		} else if (compress_name) {
484			if (!message) {
485				snprintf(msg_buf, sizeof msg_buf,
486					 "compression method %s not configured",
487					 compress_name);
488				message = msg_buf;
489			}
490		} else
491			error("invalid magic at start of compressed archive");
492		if (state != Reset)
493			error("junk at the end of compressed archive");
494		this_header = saved_offset + my_inptr;
495		buf += my_inptr;
496		len -= my_inptr;
497	}
498	dir_utime();
499	kfree(name_buf);
500	kfree(symlink_buf);
501	kfree(header_buf);
502	return message;
503}
504
505static int __initdata do_retain_initrd;
506
507static int __init retain_initrd_param(char *str)
508{
509	if (*str)
510		return 0;
511	do_retain_initrd = 1;
512	return 1;
513}
514__setup("retain_initrd", retain_initrd_param);
515
516#ifdef CONFIG_ARCH_HAS_KEEPINITRD
517static int __init keepinitrd_setup(char *__unused)
518{
519	do_retain_initrd = 1;
520	return 1;
521}
522__setup("keepinitrd", keepinitrd_setup);
523#endif
524
525extern char __initramfs_start[];
526extern unsigned long __initramfs_size;
527#include <linux/initrd.h>
528#include <linux/kexec.h>
529
530void __weak free_initrd_mem(unsigned long start, unsigned long end)
531{
532	free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
533			"initrd");
534}
535
536#ifdef CONFIG_KEXEC_CORE
537static bool kexec_free_initrd(void)
538{
 
539	unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
540	unsigned long crashk_end   = (unsigned long)__va(crashk_res.end);
 
 
 
541
 
542	/*
543	 * If the initrd region is overlapped with crashkernel reserved region,
544	 * free only memory that is not part of crashkernel region.
545	 */
546	if (initrd_start >= crashk_end || initrd_end <= crashk_start)
547		return false;
548
549	/*
550	 * Initialize initrd memory region since the kexec boot does not do.
551	 */
552	memset((void *)initrd_start, 0, initrd_end - initrd_start);
553	if (initrd_start < crashk_start)
554		free_initrd_mem(initrd_start, crashk_start);
555	if (initrd_end > crashk_end)
556		free_initrd_mem(crashk_end, initrd_end);
557	return true;
 
 
 
 
558}
559#else
560static inline bool kexec_free_initrd(void)
561{
562	return false;
563}
564#endif /* CONFIG_KEXEC_CORE */
565
566#ifdef CONFIG_BLK_DEV_RAM
567#define BUF_SIZE 1024
568static void __init clean_rootfs(void)
569{
570	int fd;
571	void *buf;
572	struct linux_dirent64 *dirp;
573	int num;
574
575	fd = ksys_open("/", O_RDONLY, 0);
576	WARN_ON(fd < 0);
577	if (fd < 0)
578		return;
579	buf = kzalloc(BUF_SIZE, GFP_KERNEL);
580	WARN_ON(!buf);
581	if (!buf) {
582		ksys_close(fd);
583		return;
584	}
585
586	dirp = buf;
587	num = ksys_getdents64(fd, dirp, BUF_SIZE);
588	while (num > 0) {
589		while (num > 0) {
590			struct kstat st;
591			int ret;
592
593			ret = vfs_lstat(dirp->d_name, &st);
594			WARN_ON_ONCE(ret);
595			if (!ret) {
596				if (S_ISDIR(st.mode))
597					ksys_rmdir(dirp->d_name);
598				else
599					ksys_unlink(dirp->d_name);
600			}
601
602			num -= dirp->d_reclen;
603			dirp = (void *)dirp + dirp->d_reclen;
604		}
605		dirp = buf;
606		memset(buf, 0, BUF_SIZE);
607		num = ksys_getdents64(fd, dirp, BUF_SIZE);
608	}
609
610	ksys_close(fd);
611	kfree(buf);
612}
613#else
614static inline void clean_rootfs(void)
615{
616}
617#endif /* CONFIG_BLK_DEV_RAM */
618
619#ifdef CONFIG_BLK_DEV_RAM
620static void __init populate_initrd_image(char *err)
621{
622	ssize_t written;
623	int fd;
624
625	unpack_to_rootfs(__initramfs_start, __initramfs_size);
626
627	printk(KERN_INFO "rootfs image is not initramfs (%s); looks like an initrd\n",
628			err);
629	fd = ksys_open("/initrd.image", O_WRONLY | O_CREAT, 0700);
630	if (fd < 0)
631		return;
632
633	written = xwrite(fd, (char *)initrd_start, initrd_end - initrd_start);
634	if (written != initrd_end - initrd_start)
635		pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
636		       written, initrd_end - initrd_start);
637	ksys_close(fd);
638}
639#else
640static void __init populate_initrd_image(char *err)
641{
642	printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
643}
644#endif /* CONFIG_BLK_DEV_RAM */
645
646static int __init populate_rootfs(void)
647{
648	/* Load the built in initramfs */
649	char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
650	if (err)
651		panic("%s", err); /* Failed to decompress INTERNAL initramfs */
652
653	if (!initrd_start || IS_ENABLED(CONFIG_INITRAMFS_FORCE))
654		goto done;
655
656	if (IS_ENABLED(CONFIG_BLK_DEV_RAM))
657		printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
658	else
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
659		printk(KERN_INFO "Unpacking initramfs...\n");
660
661	err = unpack_to_rootfs((char *)initrd_start, initrd_end - initrd_start);
662	if (err) {
663		clean_rootfs();
664		populate_initrd_image(err);
 
665	}
666
667done:
668	/*
669	 * If the initrd region is overlapped with crashkernel reserved region,
670	 * free only memory that is not part of crashkernel region.
671	 */
672	if (!do_retain_initrd && initrd_start && !kexec_free_initrd())
673		free_initrd_mem(initrd_start, initrd_end);
674	initrd_start = 0;
675	initrd_end = 0;
676
677	flush_delayed_fput();
678	return 0;
679}
680rootfs_initcall(populate_rootfs);