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v4.6
  1/*
  2 * Many of the syscalls used in this file expect some of the arguments
  3 * to be __user pointers not __kernel pointers.  To limit the sparse
  4 * noise, turn off sparse checking for this file.
  5 */
  6#ifdef __CHECKER__
  7#undef __CHECKER__
  8#warning "Sparse checking disabled for this file"
  9#endif
 10
 11#include <linux/init.h>
 
 12#include <linux/fs.h>
 13#include <linux/slab.h>
 14#include <linux/types.h>
 15#include <linux/fcntl.h>
 16#include <linux/delay.h>
 17#include <linux/string.h>
 18#include <linux/dirent.h>
 19#include <linux/syscalls.h>
 20#include <linux/utime.h>
 
 
 
 
 
 
 
 
 21
 22static ssize_t __init xwrite(int fd, const char *p, size_t count)
 
 
 
 
 23{
 24	ssize_t out = 0;
 25
 26	/* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */
 27	while (count) {
 28		ssize_t rv = sys_write(fd, p, count);
 29
 30		if (rv < 0) {
 31			if (rv == -EINTR || rv == -EAGAIN)
 32				continue;
 33			return out ? out : rv;
 34		} else if (rv == 0)
 35			break;
 36
 
 
 
 
 
 
 
 37		p += rv;
 38		out += rv;
 39		count -= rv;
 40	}
 41
 42	return out;
 43}
 44
 45static __initdata char *message;
 46static void __init error(char *x)
 47{
 48	if (!message)
 49		message = x;
 50}
 51
 
 
 
 52/* link hash */
 53
 54#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
 55
 56static __initdata struct hash {
 57	int ino, minor, major;
 58	umode_t mode;
 59	struct hash *next;
 60	char name[N_ALIGN(PATH_MAX)];
 61} *head[32];
 62
 63static inline int hash(int major, int minor, int ino)
 64{
 65	unsigned long tmp = ino + minor + (major << 3);
 66	tmp += tmp >> 5;
 67	return tmp & 31;
 68}
 69
 70static char __init *find_link(int major, int minor, int ino,
 71			      umode_t mode, char *name)
 72{
 73	struct hash **p, *q;
 74	for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
 75		if ((*p)->ino != ino)
 76			continue;
 77		if ((*p)->minor != minor)
 78			continue;
 79		if ((*p)->major != major)
 80			continue;
 81		if (((*p)->mode ^ mode) & S_IFMT)
 82			continue;
 83		return (*p)->name;
 84	}
 85	q = kmalloc(sizeof(struct hash), GFP_KERNEL);
 86	if (!q)
 87		panic("can't allocate link hash entry");
 88	q->major = major;
 89	q->minor = minor;
 90	q->ino = ino;
 91	q->mode = mode;
 92	strcpy(q->name, name);
 93	q->next = NULL;
 94	*p = q;
 95	return NULL;
 96}
 97
 98static void __init free_hash(void)
 99{
100	struct hash **p, *q;
101	for (p = head; p < head + 32; p++) {
102		while (*p) {
103			q = *p;
104			*p = q->next;
105			kfree(q);
106		}
107	}
108}
109
110static long __init do_utime(char *filename, time_t mtime)
 
111{
112	struct timespec t[2];
113
114	t[0].tv_sec = mtime;
115	t[0].tv_nsec = 0;
116	t[1].tv_sec = mtime;
117	t[1].tv_nsec = 0;
118
119	return do_utimes(AT_FDCWD, filename, t, AT_SYMLINK_NOFOLLOW);
 
 
 
120}
121
122static __initdata LIST_HEAD(dir_list);
123struct dir_entry {
124	struct list_head list;
125	char *name;
126	time_t mtime;
127};
128
129static void __init dir_add(const char *name, time_t mtime)
130{
131	struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL);
 
 
 
132	if (!de)
133		panic("can't allocate dir_entry buffer");
134	INIT_LIST_HEAD(&de->list);
135	de->name = kstrdup(name, GFP_KERNEL);
136	de->mtime = mtime;
137	list_add(&de->list, &dir_list);
138}
139
140static void __init dir_utime(void)
141{
142	struct dir_entry *de, *tmp;
143	list_for_each_entry_safe(de, tmp, &dir_list, list) {
144		list_del(&de->list);
145		do_utime(de->name, de->mtime);
146		kfree(de->name);
147		kfree(de);
148	}
149}
 
 
 
 
 
 
150
151static __initdata time_t mtime;
152
153/* cpio header parsing */
154
155static __initdata unsigned long ino, major, minor, nlink;
156static __initdata umode_t mode;
157static __initdata unsigned long body_len, name_len;
158static __initdata uid_t uid;
159static __initdata gid_t gid;
160static __initdata unsigned rdev;
 
161
162static void __init parse_header(char *s)
163{
164	unsigned long parsed[12];
165	char buf[9];
166	int i;
167
168	buf[8] = '\0';
169	for (i = 0, s += 6; i < 12; i++, s += 8) {
170		memcpy(buf, s, 8);
171		parsed[i] = simple_strtoul(buf, NULL, 16);
172	}
173	ino = parsed[0];
174	mode = parsed[1];
175	uid = parsed[2];
176	gid = parsed[3];
177	nlink = parsed[4];
178	mtime = parsed[5];
179	body_len = parsed[6];
180	major = parsed[7];
181	minor = parsed[8];
182	rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
183	name_len = parsed[11];
 
184}
185
186/* FSM */
187
188static __initdata enum state {
189	Start,
190	Collect,
191	GotHeader,
192	SkipIt,
193	GotName,
194	CopyFile,
195	GotSymlink,
196	Reset
197} state, next_state;
198
199static __initdata char *victim;
200static unsigned long byte_count __initdata;
201static __initdata loff_t this_header, next_header;
202
203static inline void __init eat(unsigned n)
204{
205	victim += n;
206	this_header += n;
207	byte_count -= n;
208}
209
210static __initdata char *vcollected;
211static __initdata char *collected;
212static long remains __initdata;
213static __initdata char *collect;
214
215static void __init read_into(char *buf, unsigned size, enum state next)
216{
217	if (byte_count >= size) {
218		collected = victim;
219		eat(size);
220		state = next;
221	} else {
222		collect = collected = buf;
223		remains = size;
224		next_state = next;
225		state = Collect;
226	}
227}
228
229static __initdata char *header_buf, *symlink_buf, *name_buf;
230
231static int __init do_start(void)
232{
233	read_into(header_buf, 110, GotHeader);
234	return 0;
235}
236
237static int __init do_collect(void)
238{
239	unsigned long n = remains;
240	if (byte_count < n)
241		n = byte_count;
242	memcpy(collect, victim, n);
243	eat(n);
244	collect += n;
245	if ((remains -= n) != 0)
246		return 1;
247	state = next_state;
248	return 0;
249}
250
251static int __init do_header(void)
252{
253	if (memcmp(collected, "070707", 6)==0) {
254		error("incorrect cpio method used: use -H newc option");
255		return 1;
256	}
257	if (memcmp(collected, "070701", 6)) {
258		error("no cpio magic");
 
 
 
259		return 1;
260	}
261	parse_header(collected);
262	next_header = this_header + N_ALIGN(name_len) + body_len;
263	next_header = (next_header + 3) & ~3;
264	state = SkipIt;
265	if (name_len <= 0 || name_len > PATH_MAX)
266		return 0;
267	if (S_ISLNK(mode)) {
268		if (body_len > PATH_MAX)
269			return 0;
270		collect = collected = symlink_buf;
271		remains = N_ALIGN(name_len) + body_len;
272		next_state = GotSymlink;
273		state = Collect;
274		return 0;
275	}
276	if (S_ISREG(mode) || !body_len)
277		read_into(name_buf, N_ALIGN(name_len), GotName);
278	return 0;
279}
280
281static int __init do_skip(void)
282{
283	if (this_header + byte_count < next_header) {
284		eat(byte_count);
285		return 1;
286	} else {
287		eat(next_header - this_header);
288		state = next_state;
289		return 0;
290	}
291}
292
293static int __init do_reset(void)
294{
295	while (byte_count && *victim == '\0')
296		eat(1);
297	if (byte_count && (this_header & 3))
298		error("broken padding");
299	return 1;
300}
301
302static int __init maybe_link(void)
303{
304	if (nlink >= 2) {
305		char *old = find_link(major, minor, ino, mode, collected);
306		if (old)
307			return (sys_link(old, collected) < 0) ? -1 : 1;
 
 
 
 
308	}
309	return 0;
310}
311
312static void __init clean_path(char *path, umode_t fmode)
313{
314	struct stat st;
315
316	if (!sys_newlstat(path, &st) && (st.st_mode ^ fmode) & S_IFMT) {
317		if (S_ISDIR(st.st_mode))
318			sys_rmdir(path);
319		else
320			sys_unlink(path);
321	}
 
322}
323
324static __initdata int wfd;
 
325
326static int __init do_name(void)
327{
328	state = SkipIt;
329	next_state = Reset;
330	if (strcmp(collected, "TRAILER!!!") == 0) {
331		free_hash();
332		return 0;
333	}
334	clean_path(collected, mode);
335	if (S_ISREG(mode)) {
336		int ml = maybe_link();
337		if (ml >= 0) {
338			int openflags = O_WRONLY|O_CREAT;
339			if (ml != 1)
340				openflags |= O_TRUNC;
341			wfd = sys_open(collected, openflags, mode);
342
343			if (wfd >= 0) {
344				sys_fchown(wfd, uid, gid);
345				sys_fchmod(wfd, mode);
346				if (body_len)
347					sys_ftruncate(wfd, body_len);
348				vcollected = kstrdup(collected, GFP_KERNEL);
349				state = CopyFile;
350			}
 
351		}
352	} else if (S_ISDIR(mode)) {
353		sys_mkdir(collected, mode);
354		sys_chown(collected, uid, gid);
355		sys_chmod(collected, mode);
356		dir_add(collected, mtime);
357	} else if (S_ISBLK(mode) || S_ISCHR(mode) ||
358		   S_ISFIFO(mode) || S_ISSOCK(mode)) {
359		if (maybe_link() == 0) {
360			sys_mknod(collected, mode, rdev);
361			sys_chown(collected, uid, gid);
362			sys_chmod(collected, mode);
363			do_utime(collected, mtime);
364		}
365	}
366	return 0;
367}
368
369static int __init do_copy(void)
370{
371	if (byte_count >= body_len) {
372		if (xwrite(wfd, victim, body_len) != body_len)
373			error("write error");
374		sys_close(wfd);
375		do_utime(vcollected, mtime);
376		kfree(vcollected);
 
 
377		eat(body_len);
378		state = SkipIt;
379		return 0;
380	} else {
381		if (xwrite(wfd, victim, byte_count) != byte_count)
382			error("write error");
383		body_len -= byte_count;
384		eat(byte_count);
385		return 1;
386	}
387}
388
389static int __init do_symlink(void)
390{
391	collected[N_ALIGN(name_len) + body_len] = '\0';
392	clean_path(collected, 0);
393	sys_symlink(collected + N_ALIGN(name_len), collected);
394	sys_lchown(collected, uid, gid);
395	do_utime(collected, mtime);
396	state = SkipIt;
397	next_state = Reset;
398	return 0;
399}
400
401static __initdata int (*actions[])(void) = {
402	[Start]		= do_start,
403	[Collect]	= do_collect,
404	[GotHeader]	= do_header,
405	[SkipIt]	= do_skip,
406	[GotName]	= do_name,
407	[CopyFile]	= do_copy,
408	[GotSymlink]	= do_symlink,
409	[Reset]		= do_reset,
410};
411
412static long __init write_buffer(char *buf, unsigned long len)
413{
414	byte_count = len;
415	victim = buf;
416
417	while (!actions[state]())
418		;
419	return len - byte_count;
420}
421
422static long __init flush_buffer(void *bufv, unsigned long len)
423{
424	char *buf = (char *) bufv;
425	long written;
426	long origLen = len;
427	if (message)
428		return -1;
429	while ((written = write_buffer(buf, len)) < len && !message) {
430		char c = buf[written];
431		if (c == '0') {
432			buf += written;
433			len -= written;
434			state = Start;
435		} else if (c == 0) {
436			buf += written;
437			len -= written;
438			state = Reset;
439		} else
440			error("junk in compressed archive");
441	}
442	return origLen;
443}
444
445static unsigned long my_inptr; /* index of next byte to be processed in inbuf */
446
447#include <linux/decompress/generic.h>
448
449static char * __init unpack_to_rootfs(char *buf, unsigned long len)
450{
451	long written;
452	decompress_fn decompress;
453	const char *compress_name;
454	static __initdata char msg_buf[64];
455
456	header_buf = kmalloc(110, GFP_KERNEL);
457	symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
458	name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
459
460	if (!header_buf || !symlink_buf || !name_buf)
461		panic("can't allocate buffers");
462
463	state = Start;
464	this_header = 0;
465	message = NULL;
466	while (!message && len) {
467		loff_t saved_offset = this_header;
468		if (*buf == '0' && !(this_header & 3)) {
469			state = Start;
470			written = write_buffer(buf, len);
471			buf += written;
472			len -= written;
473			continue;
474		}
475		if (!*buf) {
476			buf++;
477			len--;
478			this_header++;
479			continue;
480		}
481		this_header = 0;
482		decompress = decompress_method(buf, len, &compress_name);
483		pr_debug("Detected %s compressed data\n", compress_name);
484		if (decompress) {
485			int res = decompress(buf, len, NULL, flush_buffer, NULL,
486				   &my_inptr, error);
487			if (res)
488				error("decompressor failed");
489		} else if (compress_name) {
490			if (!message) {
491				snprintf(msg_buf, sizeof msg_buf,
492					 "compression method %s not configured",
493					 compress_name);
494				message = msg_buf;
495			}
496		} else
497			error("junk in compressed archive");
498		if (state != Reset)
499			error("junk in compressed archive");
500		this_header = saved_offset + my_inptr;
501		buf += my_inptr;
502		len -= my_inptr;
503	}
504	dir_utime();
505	kfree(name_buf);
506	kfree(symlink_buf);
507	kfree(header_buf);
508	return message;
509}
510
511static int __initdata do_retain_initrd;
512
513static int __init retain_initrd_param(char *str)
514{
515	if (*str)
516		return 0;
517	do_retain_initrd = 1;
518	return 1;
519}
520__setup("retain_initrd", retain_initrd_param);
521
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
522extern char __initramfs_start[];
523extern unsigned long __initramfs_size;
524#include <linux/initrd.h>
525#include <linux/kexec.h>
526
527static void __init free_initrd(void)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
528{
 
 
 
 
 
 
 
 
 
 
 
529#ifdef CONFIG_KEXEC_CORE
 
 
530	unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
531	unsigned long crashk_end   = (unsigned long)__va(crashk_res.end);
532#endif
533	if (do_retain_initrd)
534		goto skip;
535
536#ifdef CONFIG_KEXEC_CORE
537	/*
538	 * If the initrd region is overlapped with crashkernel reserved region,
539	 * free only memory that is not part of crashkernel region.
540	 */
541	if (initrd_start < crashk_end && initrd_end > crashk_start) {
542		/*
543		 * Initialize initrd memory region since the kexec boot does
544		 * not do.
545		 */
546		memset((void *)initrd_start, 0, initrd_end - initrd_start);
547		if (initrd_start < crashk_start)
548			free_initrd_mem(initrd_start, crashk_start);
549		if (initrd_end > crashk_end)
550			free_initrd_mem(crashk_end, initrd_end);
551	} else
552#endif
553		free_initrd_mem(initrd_start, initrd_end);
554skip:
555	initrd_start = 0;
556	initrd_end = 0;
557}
 
 
 
 
 
 
558
559#ifdef CONFIG_BLK_DEV_RAM
560#define BUF_SIZE 1024
561static void __init clean_rootfs(void)
562{
563	int fd;
564	void *buf;
565	struct linux_dirent64 *dirp;
566	int num;
567
568	fd = sys_open("/", O_RDONLY, 0);
569	WARN_ON(fd < 0);
570	if (fd < 0)
571		return;
572	buf = kzalloc(BUF_SIZE, GFP_KERNEL);
573	WARN_ON(!buf);
574	if (!buf) {
575		sys_close(fd);
576		return;
577	}
578
579	dirp = buf;
580	num = sys_getdents64(fd, dirp, BUF_SIZE);
581	while (num > 0) {
582		while (num > 0) {
583			struct stat st;
584			int ret;
585
586			ret = sys_newlstat(dirp->d_name, &st);
587			WARN_ON_ONCE(ret);
588			if (!ret) {
589				if (S_ISDIR(st.st_mode))
590					sys_rmdir(dirp->d_name);
591				else
592					sys_unlink(dirp->d_name);
593			}
594
595			num -= dirp->d_reclen;
596			dirp = (void *)dirp + dirp->d_reclen;
597		}
598		dirp = buf;
599		memset(buf, 0, BUF_SIZE);
600		num = sys_getdents64(fd, dirp, BUF_SIZE);
601	}
602
603	sys_close(fd);
604	kfree(buf);
605}
606#endif
607
608static int __init populate_rootfs(void)
609{
 
610	char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
611	if (err)
612		panic("%s", err); /* Failed to decompress INTERNAL initramfs */
613	if (initrd_start) {
614#ifdef CONFIG_BLK_DEV_RAM
615		int fd;
 
 
616		printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
617		err = unpack_to_rootfs((char *)initrd_start,
618			initrd_end - initrd_start);
619		if (!err) {
620			free_initrd();
621			goto done;
622		} else {
623			clean_rootfs();
624			unpack_to_rootfs(__initramfs_start, __initramfs_size);
625		}
626		printk(KERN_INFO "rootfs image is not initramfs (%s)"
627				"; looks like an initrd\n", err);
628		fd = sys_open("/initrd.image",
629			      O_WRONLY|O_CREAT, 0700);
630		if (fd >= 0) {
631			ssize_t written = xwrite(fd, (char *)initrd_start,
632						initrd_end - initrd_start);
633
634			if (written != initrd_end - initrd_start)
635				pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
636				       written, initrd_end - initrd_start);
637
638			sys_close(fd);
639			free_initrd();
640		}
641	done:
642#else
643		printk(KERN_INFO "Unpacking initramfs...\n");
644		err = unpack_to_rootfs((char *)initrd_start,
645			initrd_end - initrd_start);
646		if (err)
647			printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
648		free_initrd();
649#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
650		/*
651		 * Try loading default modules from initramfs.  This gives
652		 * us a chance to load before device_initcalls.
 
 
653		 */
654		load_default_modules();
 
655	}
 
 
 
 
 
 
 
 
 
 
 
656	return 0;
657}
658rootfs_initcall(populate_rootfs);
v6.8
  1// SPDX-License-Identifier: GPL-2.0
 
 
 
 
 
 
 
 
 
  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/kstrtox.h>
 15#include <linux/memblock.h>
 16#include <linux/mm.h>
 17#include <linux/namei.h>
 18#include <linux/init_syscalls.h>
 19#include <linux/task_work.h>
 20#include <linux/umh.h>
 21
 22static __initdata bool csum_present;
 23static __initdata u32 io_csum;
 24
 25static ssize_t __init xwrite(struct file *file, const unsigned char *p,
 26		size_t count, loff_t *pos)
 27{
 28	ssize_t out = 0;
 29
 30	/* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */
 31	while (count) {
 32		ssize_t rv = kernel_write(file, p, count, pos);
 33
 34		if (rv < 0) {
 35			if (rv == -EINTR || rv == -EAGAIN)
 36				continue;
 37			return out ? out : rv;
 38		} else if (rv == 0)
 39			break;
 40
 41		if (csum_present) {
 42			ssize_t i;
 43
 44			for (i = 0; i < rv; i++)
 45				io_csum += p[i];
 46		}
 47
 48		p += rv;
 49		out += rv;
 50		count -= rv;
 51	}
 52
 53	return out;
 54}
 55
 56static __initdata char *message;
 57static void __init error(char *x)
 58{
 59	if (!message)
 60		message = x;
 61}
 62
 63#define panic_show_mem(fmt, ...) \
 64	({ show_mem(); panic(fmt, ##__VA_ARGS__); })
 65
 66/* link hash */
 67
 68#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
 69
 70static __initdata struct hash {
 71	int ino, minor, major;
 72	umode_t mode;
 73	struct hash *next;
 74	char name[N_ALIGN(PATH_MAX)];
 75} *head[32];
 76
 77static inline int hash(int major, int minor, int ino)
 78{
 79	unsigned long tmp = ino + minor + (major << 3);
 80	tmp += tmp >> 5;
 81	return tmp & 31;
 82}
 83
 84static char __init *find_link(int major, int minor, int ino,
 85			      umode_t mode, char *name)
 86{
 87	struct hash **p, *q;
 88	for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
 89		if ((*p)->ino != ino)
 90			continue;
 91		if ((*p)->minor != minor)
 92			continue;
 93		if ((*p)->major != major)
 94			continue;
 95		if (((*p)->mode ^ mode) & S_IFMT)
 96			continue;
 97		return (*p)->name;
 98	}
 99	q = kmalloc(sizeof(struct hash), GFP_KERNEL);
100	if (!q)
101		panic_show_mem("can't allocate link hash entry");
102	q->major = major;
103	q->minor = minor;
104	q->ino = ino;
105	q->mode = mode;
106	strcpy(q->name, name);
107	q->next = NULL;
108	*p = q;
109	return NULL;
110}
111
112static void __init free_hash(void)
113{
114	struct hash **p, *q;
115	for (p = head; p < head + 32; p++) {
116		while (*p) {
117			q = *p;
118			*p = q->next;
119			kfree(q);
120		}
121	}
122}
123
124#ifdef CONFIG_INITRAMFS_PRESERVE_MTIME
125static void __init do_utime(char *filename, time64_t mtime)
126{
127	struct timespec64 t[2] = { { .tv_sec = mtime }, { .tv_sec = mtime } };
128	init_utimes(filename, t);
129}
 
 
 
130
131static void __init do_utime_path(const struct path *path, time64_t mtime)
132{
133	struct timespec64 t[2] = { { .tv_sec = mtime }, { .tv_sec = mtime } };
134	vfs_utimes(path, t);
135}
136
137static __initdata LIST_HEAD(dir_list);
138struct dir_entry {
139	struct list_head list;
140	time64_t mtime;
141	char name[];
142};
143
144static void __init dir_add(const char *name, time64_t mtime)
145{
146	size_t nlen = strlen(name) + 1;
147	struct dir_entry *de;
148
149	de = kmalloc(sizeof(struct dir_entry) + nlen, GFP_KERNEL);
150	if (!de)
151		panic_show_mem("can't allocate dir_entry buffer");
152	INIT_LIST_HEAD(&de->list);
153	strscpy(de->name, name, nlen);
154	de->mtime = mtime;
155	list_add(&de->list, &dir_list);
156}
157
158static void __init dir_utime(void)
159{
160	struct dir_entry *de, *tmp;
161	list_for_each_entry_safe(de, tmp, &dir_list, list) {
162		list_del(&de->list);
163		do_utime(de->name, de->mtime);
 
164		kfree(de);
165	}
166}
167#else
168static void __init do_utime(char *filename, time64_t mtime) {}
169static void __init do_utime_path(const struct path *path, time64_t mtime) {}
170static void __init dir_add(const char *name, time64_t mtime) {}
171static void __init dir_utime(void) {}
172#endif
173
174static __initdata time64_t mtime;
175
176/* cpio header parsing */
177
178static __initdata unsigned long ino, major, minor, nlink;
179static __initdata umode_t mode;
180static __initdata unsigned long body_len, name_len;
181static __initdata uid_t uid;
182static __initdata gid_t gid;
183static __initdata unsigned rdev;
184static __initdata u32 hdr_csum;
185
186static void __init parse_header(char *s)
187{
188	unsigned long parsed[13];
189	char buf[9];
190	int i;
191
192	buf[8] = '\0';
193	for (i = 0, s += 6; i < 13; i++, s += 8) {
194		memcpy(buf, s, 8);
195		parsed[i] = simple_strtoul(buf, NULL, 16);
196	}
197	ino = parsed[0];
198	mode = parsed[1];
199	uid = parsed[2];
200	gid = parsed[3];
201	nlink = parsed[4];
202	mtime = parsed[5]; /* breaks in y2106 */
203	body_len = parsed[6];
204	major = parsed[7];
205	minor = parsed[8];
206	rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
207	name_len = parsed[11];
208	hdr_csum = parsed[12];
209}
210
211/* FSM */
212
213static __initdata enum state {
214	Start,
215	Collect,
216	GotHeader,
217	SkipIt,
218	GotName,
219	CopyFile,
220	GotSymlink,
221	Reset
222} state, next_state;
223
224static __initdata char *victim;
225static unsigned long byte_count __initdata;
226static __initdata loff_t this_header, next_header;
227
228static inline void __init eat(unsigned n)
229{
230	victim += n;
231	this_header += n;
232	byte_count -= n;
233}
234
 
235static __initdata char *collected;
236static long remains __initdata;
237static __initdata char *collect;
238
239static void __init read_into(char *buf, unsigned size, enum state next)
240{
241	if (byte_count >= size) {
242		collected = victim;
243		eat(size);
244		state = next;
245	} else {
246		collect = collected = buf;
247		remains = size;
248		next_state = next;
249		state = Collect;
250	}
251}
252
253static __initdata char *header_buf, *symlink_buf, *name_buf;
254
255static int __init do_start(void)
256{
257	read_into(header_buf, 110, GotHeader);
258	return 0;
259}
260
261static int __init do_collect(void)
262{
263	unsigned long n = remains;
264	if (byte_count < n)
265		n = byte_count;
266	memcpy(collect, victim, n);
267	eat(n);
268	collect += n;
269	if ((remains -= n) != 0)
270		return 1;
271	state = next_state;
272	return 0;
273}
274
275static int __init do_header(void)
276{
277	if (!memcmp(collected, "070701", 6)) {
278		csum_present = false;
279	} else if (!memcmp(collected, "070702", 6)) {
280		csum_present = true;
281	} else {
282		if (memcmp(collected, "070707", 6) == 0)
283			error("incorrect cpio method used: use -H newc option");
284		else
285			error("no cpio magic");
286		return 1;
287	}
288	parse_header(collected);
289	next_header = this_header + N_ALIGN(name_len) + body_len;
290	next_header = (next_header + 3) & ~3;
291	state = SkipIt;
292	if (name_len <= 0 || name_len > PATH_MAX)
293		return 0;
294	if (S_ISLNK(mode)) {
295		if (body_len > PATH_MAX)
296			return 0;
297		collect = collected = symlink_buf;
298		remains = N_ALIGN(name_len) + body_len;
299		next_state = GotSymlink;
300		state = Collect;
301		return 0;
302	}
303	if (S_ISREG(mode) || !body_len)
304		read_into(name_buf, N_ALIGN(name_len), GotName);
305	return 0;
306}
307
308static int __init do_skip(void)
309{
310	if (this_header + byte_count < next_header) {
311		eat(byte_count);
312		return 1;
313	} else {
314		eat(next_header - this_header);
315		state = next_state;
316		return 0;
317	}
318}
319
320static int __init do_reset(void)
321{
322	while (byte_count && *victim == '\0')
323		eat(1);
324	if (byte_count && (this_header & 3))
325		error("broken padding");
326	return 1;
327}
328
329static void __init clean_path(char *path, umode_t fmode)
330{
331	struct kstat st;
332
333	if (!init_stat(path, &st, AT_SYMLINK_NOFOLLOW) &&
334	    (st.mode ^ fmode) & S_IFMT) {
335		if (S_ISDIR(st.mode))
336			init_rmdir(path);
337		else
338			init_unlink(path);
339	}
 
340}
341
342static int __init maybe_link(void)
343{
344	if (nlink >= 2) {
345		char *old = find_link(major, minor, ino, mode, collected);
346		if (old) {
347			clean_path(collected, 0);
348			return (init_link(old, collected) < 0) ? -1 : 1;
349		}
 
350	}
351	return 0;
352}
353
354static __initdata struct file *wfile;
355static __initdata loff_t wfile_pos;
356
357static int __init do_name(void)
358{
359	state = SkipIt;
360	next_state = Reset;
361	if (strcmp(collected, "TRAILER!!!") == 0) {
362		free_hash();
363		return 0;
364	}
365	clean_path(collected, mode);
366	if (S_ISREG(mode)) {
367		int ml = maybe_link();
368		if (ml >= 0) {
369			int openflags = O_WRONLY|O_CREAT;
370			if (ml != 1)
371				openflags |= O_TRUNC;
372			wfile = filp_open(collected, openflags, mode);
373			if (IS_ERR(wfile))
374				return 0;
375			wfile_pos = 0;
376			io_csum = 0;
377
378			vfs_fchown(wfile, uid, gid);
379			vfs_fchmod(wfile, mode);
380			if (body_len)
381				vfs_truncate(&wfile->f_path, body_len);
382			state = CopyFile;
383		}
384	} else if (S_ISDIR(mode)) {
385		init_mkdir(collected, mode);
386		init_chown(collected, uid, gid, 0);
387		init_chmod(collected, mode);
388		dir_add(collected, mtime);
389	} else if (S_ISBLK(mode) || S_ISCHR(mode) ||
390		   S_ISFIFO(mode) || S_ISSOCK(mode)) {
391		if (maybe_link() == 0) {
392			init_mknod(collected, mode, rdev);
393			init_chown(collected, uid, gid, 0);
394			init_chmod(collected, mode);
395			do_utime(collected, mtime);
396		}
397	}
398	return 0;
399}
400
401static int __init do_copy(void)
402{
403	if (byte_count >= body_len) {
404		if (xwrite(wfile, victim, body_len, &wfile_pos) != body_len)
405			error("write error");
406
407		do_utime_path(&wfile->f_path, mtime);
408		fput(wfile);
409		if (csum_present && io_csum != hdr_csum)
410			error("bad data checksum");
411		eat(body_len);
412		state = SkipIt;
413		return 0;
414	} else {
415		if (xwrite(wfile, victim, byte_count, &wfile_pos) != byte_count)
416			error("write error");
417		body_len -= byte_count;
418		eat(byte_count);
419		return 1;
420	}
421}
422
423static int __init do_symlink(void)
424{
425	collected[N_ALIGN(name_len) + body_len] = '\0';
426	clean_path(collected, 0);
427	init_symlink(collected + N_ALIGN(name_len), collected);
428	init_chown(collected, uid, gid, AT_SYMLINK_NOFOLLOW);
429	do_utime(collected, mtime);
430	state = SkipIt;
431	next_state = Reset;
432	return 0;
433}
434
435static __initdata int (*actions[])(void) = {
436	[Start]		= do_start,
437	[Collect]	= do_collect,
438	[GotHeader]	= do_header,
439	[SkipIt]	= do_skip,
440	[GotName]	= do_name,
441	[CopyFile]	= do_copy,
442	[GotSymlink]	= do_symlink,
443	[Reset]		= do_reset,
444};
445
446static long __init write_buffer(char *buf, unsigned long len)
447{
448	byte_count = len;
449	victim = buf;
450
451	while (!actions[state]())
452		;
453	return len - byte_count;
454}
455
456static long __init flush_buffer(void *bufv, unsigned long len)
457{
458	char *buf = bufv;
459	long written;
460	long origLen = len;
461	if (message)
462		return -1;
463	while ((written = write_buffer(buf, len)) < len && !message) {
464		char c = buf[written];
465		if (c == '0') {
466			buf += written;
467			len -= written;
468			state = Start;
469		} else if (c == 0) {
470			buf += written;
471			len -= written;
472			state = Reset;
473		} else
474			error("junk within compressed archive");
475	}
476	return origLen;
477}
478
479static unsigned long my_inptr __initdata; /* index of next byte to be processed in inbuf */
480
481#include <linux/decompress/generic.h>
482
483static char * __init unpack_to_rootfs(char *buf, unsigned long len)
484{
485	long written;
486	decompress_fn decompress;
487	const char *compress_name;
488	static __initdata char msg_buf[64];
489
490	header_buf = kmalloc(110, GFP_KERNEL);
491	symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
492	name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
493
494	if (!header_buf || !symlink_buf || !name_buf)
495		panic_show_mem("can't allocate buffers");
496
497	state = Start;
498	this_header = 0;
499	message = NULL;
500	while (!message && len) {
501		loff_t saved_offset = this_header;
502		if (*buf == '0' && !(this_header & 3)) {
503			state = Start;
504			written = write_buffer(buf, len);
505			buf += written;
506			len -= written;
507			continue;
508		}
509		if (!*buf) {
510			buf++;
511			len--;
512			this_header++;
513			continue;
514		}
515		this_header = 0;
516		decompress = decompress_method(buf, len, &compress_name);
517		pr_debug("Detected %s compressed data\n", compress_name);
518		if (decompress) {
519			int res = decompress(buf, len, NULL, flush_buffer, NULL,
520				   &my_inptr, error);
521			if (res)
522				error("decompressor failed");
523		} else if (compress_name) {
524			if (!message) {
525				snprintf(msg_buf, sizeof msg_buf,
526					 "compression method %s not configured",
527					 compress_name);
528				message = msg_buf;
529			}
530		} else
531			error("invalid magic at start of compressed archive");
532		if (state != Reset)
533			error("junk at the end of compressed archive");
534		this_header = saved_offset + my_inptr;
535		buf += my_inptr;
536		len -= my_inptr;
537	}
538	dir_utime();
539	kfree(name_buf);
540	kfree(symlink_buf);
541	kfree(header_buf);
542	return message;
543}
544
545static int __initdata do_retain_initrd;
546
547static int __init retain_initrd_param(char *str)
548{
549	if (*str)
550		return 0;
551	do_retain_initrd = 1;
552	return 1;
553}
554__setup("retain_initrd", retain_initrd_param);
555
556#ifdef CONFIG_ARCH_HAS_KEEPINITRD
557static int __init keepinitrd_setup(char *__unused)
558{
559	do_retain_initrd = 1;
560	return 1;
561}
562__setup("keepinitrd", keepinitrd_setup);
563#endif
564
565static bool __initdata initramfs_async = true;
566static int __init initramfs_async_setup(char *str)
567{
568	return kstrtobool(str, &initramfs_async) == 0;
569}
570__setup("initramfs_async=", initramfs_async_setup);
571
572extern char __initramfs_start[];
573extern unsigned long __initramfs_size;
574#include <linux/initrd.h>
575#include <linux/kexec.h>
576
577static ssize_t raw_read(struct file *file, struct kobject *kobj,
578			struct bin_attribute *attr, char *buf,
579			loff_t pos, size_t count)
580{
581	memcpy(buf, attr->private + pos, count);
582	return count;
583}
584
585static BIN_ATTR(initrd, 0440, raw_read, NULL, 0);
586
587void __init reserve_initrd_mem(void)
588{
589	phys_addr_t start;
590	unsigned long size;
591
592	/* Ignore the virtul address computed during device tree parsing */
593	initrd_start = initrd_end = 0;
594
595	if (!phys_initrd_size)
596		return;
597	/*
598	 * Round the memory region to page boundaries as per free_initrd_mem()
599	 * This allows us to detect whether the pages overlapping the initrd
600	 * are in use, but more importantly, reserves the entire set of pages
601	 * as we don't want these pages allocated for other purposes.
602	 */
603	start = round_down(phys_initrd_start, PAGE_SIZE);
604	size = phys_initrd_size + (phys_initrd_start - start);
605	size = round_up(size, PAGE_SIZE);
606
607	if (!memblock_is_region_memory(start, size)) {
608		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
609		       (u64)start, size);
610		goto disable;
611	}
612
613	if (memblock_is_region_reserved(start, size)) {
614		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
615		       (u64)start, size);
616		goto disable;
617	}
618
619	memblock_reserve(start, size);
620	/* Now convert initrd to virtual addresses */
621	initrd_start = (unsigned long)__va(phys_initrd_start);
622	initrd_end = initrd_start + phys_initrd_size;
623	initrd_below_start_ok = 1;
624
625	return;
626disable:
627	pr_cont(" - disabling initrd\n");
628	initrd_start = 0;
629	initrd_end = 0;
630}
631
632void __weak __init free_initrd_mem(unsigned long start, unsigned long end)
633{
634#ifdef CONFIG_ARCH_KEEP_MEMBLOCK
635	unsigned long aligned_start = ALIGN_DOWN(start, PAGE_SIZE);
636	unsigned long aligned_end = ALIGN(end, PAGE_SIZE);
637
638	memblock_free((void *)aligned_start, aligned_end - aligned_start);
639#endif
640
641	free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
642			"initrd");
643}
644
645#ifdef CONFIG_KEXEC_CORE
646static bool __init kexec_free_initrd(void)
647{
648	unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
649	unsigned long crashk_end   = (unsigned long)__va(crashk_res.end);
 
 
 
650
 
651	/*
652	 * If the initrd region is overlapped with crashkernel reserved region,
653	 * free only memory that is not part of crashkernel region.
654	 */
655	if (initrd_start >= crashk_end || initrd_end <= crashk_start)
656		return false;
657
658	/*
659	 * Initialize initrd memory region since the kexec boot does not do.
660	 */
661	memset((void *)initrd_start, 0, initrd_end - initrd_start);
662	if (initrd_start < crashk_start)
663		free_initrd_mem(initrd_start, crashk_start);
664	if (initrd_end > crashk_end)
665		free_initrd_mem(crashk_end, initrd_end);
666	return true;
 
 
 
 
667}
668#else
669static inline bool kexec_free_initrd(void)
670{
671	return false;
672}
673#endif /* CONFIG_KEXEC_CORE */
674
675#ifdef CONFIG_BLK_DEV_RAM
676static void __init populate_initrd_image(char *err)
 
677{
678	ssize_t written;
679	struct file *file;
680	loff_t pos = 0;
681
682	unpack_to_rootfs(__initramfs_start, __initramfs_size);
683
684	printk(KERN_INFO "rootfs image is not initramfs (%s); looks like an initrd\n",
685			err);
686	file = filp_open("/initrd.image", O_WRONLY | O_CREAT, 0700);
687	if (IS_ERR(file))
 
 
 
688		return;
 
689
690	written = xwrite(file, (char *)initrd_start, initrd_end - initrd_start,
691			&pos);
692	if (written != initrd_end - initrd_start)
693		pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
694		       written, initrd_end - initrd_start);
695	fput(file);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
696}
697#endif /* CONFIG_BLK_DEV_RAM */
698
699static void __init do_populate_rootfs(void *unused, async_cookie_t cookie)
700{
701	/* Load the built in initramfs */
702	char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
703	if (err)
704		panic_show_mem("%s", err); /* Failed to decompress INTERNAL initramfs */
705
706	if (!initrd_start || IS_ENABLED(CONFIG_INITRAMFS_FORCE))
707		goto done;
708
709	if (IS_ENABLED(CONFIG_BLK_DEV_RAM))
710		printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
711	else
712		printk(KERN_INFO "Unpacking initramfs...\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
713
714	err = unpack_to_rootfs((char *)initrd_start, initrd_end - initrd_start);
715	if (err) {
716#ifdef CONFIG_BLK_DEV_RAM
717		populate_initrd_image(err);
718#else
719		printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
 
 
 
 
 
720#endif
721	}
722
723done:
724	/*
725	 * If the initrd region is overlapped with crashkernel reserved region,
726	 * free only memory that is not part of crashkernel region.
727	 */
728	if (!do_retain_initrd && initrd_start && !kexec_free_initrd()) {
729		free_initrd_mem(initrd_start, initrd_end);
730	} else if (do_retain_initrd && initrd_start) {
731		bin_attr_initrd.size = initrd_end - initrd_start;
732		bin_attr_initrd.private = (void *)initrd_start;
733		if (sysfs_create_bin_file(firmware_kobj, &bin_attr_initrd))
734			pr_err("Failed to create initrd sysfs file");
735	}
736	initrd_start = 0;
737	initrd_end = 0;
738
739	flush_delayed_fput();
740	task_work_run();
741}
742
743static ASYNC_DOMAIN_EXCLUSIVE(initramfs_domain);
744static async_cookie_t initramfs_cookie;
745
746void wait_for_initramfs(void)
747{
748	if (!initramfs_cookie) {
749		/*
750		 * Something before rootfs_initcall wants to access
751		 * the filesystem/initramfs. Probably a bug. Make a
752		 * note, avoid deadlocking the machine, and let the
753		 * caller's access fail as it used to.
754		 */
755		pr_warn_once("wait_for_initramfs() called before rootfs_initcalls\n");
756		return;
757	}
758	async_synchronize_cookie_domain(initramfs_cookie + 1, &initramfs_domain);
759}
760EXPORT_SYMBOL_GPL(wait_for_initramfs);
761
762static int __init populate_rootfs(void)
763{
764	initramfs_cookie = async_schedule_domain(do_populate_rootfs, NULL,
765						 &initramfs_domain);
766	usermodehelper_enable();
767	if (!initramfs_async)
768		wait_for_initramfs();
769	return 0;
770}
771rootfs_initcall(populate_rootfs);