Linux Audio

Check our new training course

Loading...
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);
v6.9.4
  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/umh.h>
 20
 21#include "do_mounts.h"
 22
 23static __initdata bool csum_present;
 24static __initdata u32 io_csum;
 25
 26static ssize_t __init xwrite(struct file *file, const unsigned char *p,
 27		size_t count, loff_t *pos)
 28{
 29	ssize_t out = 0;
 30
 31	/* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */
 32	while (count) {
 33		ssize_t rv = kernel_write(file, p, count, pos);
 34
 35		if (rv < 0) {
 36			if (rv == -EINTR || rv == -EAGAIN)
 37				continue;
 38			return out ? out : rv;
 39		} else if (rv == 0)
 40			break;
 41
 42		if (csum_present) {
 43			ssize_t i;
 44
 45			for (i = 0; i < rv; i++)
 46				io_csum += p[i];
 47		}
 48
 49		p += rv;
 50		out += rv;
 51		count -= rv;
 52	}
 53
 54	return out;
 55}
 56
 57static __initdata char *message;
 58static void __init error(char *x)
 59{
 60	if (!message)
 61		message = x;
 62}
 63
 64#define panic_show_mem(fmt, ...) \
 65	({ show_mem(); panic(fmt, ##__VA_ARGS__); })
 66
 67/* link hash */
 68
 69#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
 70
 71static __initdata struct hash {
 72	int ino, minor, major;
 73	umode_t mode;
 74	struct hash *next;
 75	char name[N_ALIGN(PATH_MAX)];
 76} *head[32];
 77
 78static inline int hash(int major, int minor, int ino)
 79{
 80	unsigned long tmp = ino + minor + (major << 3);
 81	tmp += tmp >> 5;
 82	return tmp & 31;
 83}
 84
 85static char __init *find_link(int major, int minor, int ino,
 86			      umode_t mode, char *name)
 87{
 88	struct hash **p, *q;
 89	for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
 90		if ((*p)->ino != ino)
 91			continue;
 92		if ((*p)->minor != minor)
 93			continue;
 94		if ((*p)->major != major)
 95			continue;
 96		if (((*p)->mode ^ mode) & S_IFMT)
 97			continue;
 98		return (*p)->name;
 99	}
100	q = kmalloc(sizeof(struct hash), GFP_KERNEL);
101	if (!q)
102		panic_show_mem("can't allocate link hash entry");
103	q->major = major;
104	q->minor = minor;
105	q->ino = ino;
106	q->mode = mode;
107	strcpy(q->name, name);
108	q->next = NULL;
109	*p = q;
110	return NULL;
111}
112
113static void __init free_hash(void)
114{
115	struct hash **p, *q;
116	for (p = head; p < head + 32; p++) {
117		while (*p) {
118			q = *p;
119			*p = q->next;
120			kfree(q);
121		}
122	}
123}
124
125#ifdef CONFIG_INITRAMFS_PRESERVE_MTIME
126static void __init do_utime(char *filename, time64_t mtime)
127{
128	struct timespec64 t[2] = { { .tv_sec = mtime }, { .tv_sec = mtime } };
129	init_utimes(filename, t);
130}
 
 
 
131
132static void __init do_utime_path(const struct path *path, time64_t mtime)
133{
134	struct timespec64 t[2] = { { .tv_sec = mtime }, { .tv_sec = mtime } };
135	vfs_utimes(path, t);
136}
137
138static __initdata LIST_HEAD(dir_list);
139struct dir_entry {
140	struct list_head list;
141	time64_t mtime;
142	char name[];
143};
144
145static void __init dir_add(const char *name, time64_t mtime)
146{
147	size_t nlen = strlen(name) + 1;
148	struct dir_entry *de;
149
150	de = kmalloc(sizeof(struct dir_entry) + nlen, GFP_KERNEL);
151	if (!de)
152		panic_show_mem("can't allocate dir_entry buffer");
153	INIT_LIST_HEAD(&de->list);
154	strscpy(de->name, name, nlen);
155	de->mtime = mtime;
156	list_add(&de->list, &dir_list);
157}
158
159static void __init dir_utime(void)
160{
161	struct dir_entry *de, *tmp;
162	list_for_each_entry_safe(de, tmp, &dir_list, list) {
163		list_del(&de->list);
164		do_utime(de->name, de->mtime);
 
165		kfree(de);
166	}
167}
168#else
169static void __init do_utime(char *filename, time64_t mtime) {}
170static void __init do_utime_path(const struct path *path, time64_t mtime) {}
171static void __init dir_add(const char *name, time64_t mtime) {}
172static void __init dir_utime(void) {}
173#endif
174
175static __initdata time64_t mtime;
176
177/* cpio header parsing */
178
179static __initdata unsigned long ino, major, minor, nlink;
180static __initdata umode_t mode;
181static __initdata unsigned long body_len, name_len;
182static __initdata uid_t uid;
183static __initdata gid_t gid;
184static __initdata unsigned rdev;
185static __initdata u32 hdr_csum;
186
187static void __init parse_header(char *s)
188{
189	unsigned long parsed[13];
190	char buf[9];
191	int i;
192
193	buf[8] = '\0';
194	for (i = 0, s += 6; i < 13; i++, s += 8) {
195		memcpy(buf, s, 8);
196		parsed[i] = simple_strtoul(buf, NULL, 16);
197	}
198	ino = parsed[0];
199	mode = parsed[1];
200	uid = parsed[2];
201	gid = parsed[3];
202	nlink = parsed[4];
203	mtime = parsed[5]; /* breaks in y2106 */
204	body_len = parsed[6];
205	major = parsed[7];
206	minor = parsed[8];
207	rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
208	name_len = parsed[11];
209	hdr_csum = parsed[12];
210}
211
212/* FSM */
213
214static __initdata enum state {
215	Start,
216	Collect,
217	GotHeader,
218	SkipIt,
219	GotName,
220	CopyFile,
221	GotSymlink,
222	Reset
223} state, next_state;
224
225static __initdata char *victim;
226static unsigned long byte_count __initdata;
227static __initdata loff_t this_header, next_header;
228
229static inline void __init eat(unsigned n)
230{
231	victim += n;
232	this_header += n;
233	byte_count -= n;
234}
235
 
236static __initdata char *collected;
237static long remains __initdata;
238static __initdata char *collect;
239
240static void __init read_into(char *buf, unsigned size, enum state next)
241{
242	if (byte_count >= size) {
243		collected = victim;
244		eat(size);
245		state = next;
246	} else {
247		collect = collected = buf;
248		remains = size;
249		next_state = next;
250		state = Collect;
251	}
252}
253
254static __initdata char *header_buf, *symlink_buf, *name_buf;
255
256static int __init do_start(void)
257{
258	read_into(header_buf, 110, GotHeader);
259	return 0;
260}
261
262static int __init do_collect(void)
263{
264	unsigned long n = remains;
265	if (byte_count < n)
266		n = byte_count;
267	memcpy(collect, victim, n);
268	eat(n);
269	collect += n;
270	if ((remains -= n) != 0)
271		return 1;
272	state = next_state;
273	return 0;
274}
275
276static int __init do_header(void)
277{
278	if (!memcmp(collected, "070701", 6)) {
279		csum_present = false;
280	} else if (!memcmp(collected, "070702", 6)) {
281		csum_present = true;
282	} else {
283		if (memcmp(collected, "070707", 6) == 0)
284			error("incorrect cpio method used: use -H newc option");
285		else
286			error("no cpio magic");
287		return 1;
288	}
289	parse_header(collected);
290	next_header = this_header + N_ALIGN(name_len) + body_len;
291	next_header = (next_header + 3) & ~3;
292	state = SkipIt;
293	if (name_len <= 0 || name_len > PATH_MAX)
294		return 0;
295	if (S_ISLNK(mode)) {
296		if (body_len > PATH_MAX)
297			return 0;
298		collect = collected = symlink_buf;
299		remains = N_ALIGN(name_len) + body_len;
300		next_state = GotSymlink;
301		state = Collect;
302		return 0;
303	}
304	if (S_ISREG(mode) || !body_len)
305		read_into(name_buf, N_ALIGN(name_len), GotName);
306	return 0;
307}
308
309static int __init do_skip(void)
310{
311	if (this_header + byte_count < next_header) {
312		eat(byte_count);
313		return 1;
314	} else {
315		eat(next_header - this_header);
316		state = next_state;
317		return 0;
318	}
319}
320
321static int __init do_reset(void)
322{
323	while (byte_count && *victim == '\0')
324		eat(1);
325	if (byte_count && (this_header & 3))
326		error("broken padding");
327	return 1;
328}
329
330static void __init clean_path(char *path, umode_t fmode)
331{
332	struct kstat st;
333
334	if (!init_stat(path, &st, AT_SYMLINK_NOFOLLOW) &&
335	    (st.mode ^ fmode) & S_IFMT) {
336		if (S_ISDIR(st.mode))
337			init_rmdir(path);
338		else
339			init_unlink(path);
340	}
 
341}
342
343static int __init maybe_link(void)
344{
345	if (nlink >= 2) {
346		char *old = find_link(major, minor, ino, mode, collected);
347		if (old) {
348			clean_path(collected, 0);
349			return (init_link(old, collected) < 0) ? -1 : 1;
350		}
 
351	}
352	return 0;
353}
354
355static __initdata struct file *wfile;
356static __initdata loff_t wfile_pos;
357
358static int __init do_name(void)
359{
360	state = SkipIt;
361	next_state = Reset;
362	if (strcmp(collected, "TRAILER!!!") == 0) {
363		free_hash();
364		return 0;
365	}
366	clean_path(collected, mode);
367	if (S_ISREG(mode)) {
368		int ml = maybe_link();
369		if (ml >= 0) {
370			int openflags = O_WRONLY|O_CREAT|O_LARGEFILE;
371			if (ml != 1)
372				openflags |= O_TRUNC;
373			wfile = filp_open(collected, openflags, mode);
374			if (IS_ERR(wfile))
375				return 0;
376			wfile_pos = 0;
377			io_csum = 0;
378
379			vfs_fchown(wfile, uid, gid);
380			vfs_fchmod(wfile, mode);
381			if (body_len)
382				vfs_truncate(&wfile->f_path, body_len);
383			state = CopyFile;
384		}
385	} else if (S_ISDIR(mode)) {
386		init_mkdir(collected, mode);
387		init_chown(collected, uid, gid, 0);
388		init_chmod(collected, mode);
389		dir_add(collected, mtime);
390	} else if (S_ISBLK(mode) || S_ISCHR(mode) ||
391		   S_ISFIFO(mode) || S_ISSOCK(mode)) {
392		if (maybe_link() == 0) {
393			init_mknod(collected, mode, rdev);
394			init_chown(collected, uid, gid, 0);
395			init_chmod(collected, mode);
396			do_utime(collected, mtime);
397		}
398	}
399	return 0;
400}
401
402static int __init do_copy(void)
403{
404	if (byte_count >= body_len) {
405		if (xwrite(wfile, victim, body_len, &wfile_pos) != body_len)
406			error("write error");
407
408		do_utime_path(&wfile->f_path, mtime);
409		fput(wfile);
410		if (csum_present && io_csum != hdr_csum)
411			error("bad data checksum");
412		eat(body_len);
413		state = SkipIt;
414		return 0;
415	} else {
416		if (xwrite(wfile, victim, byte_count, &wfile_pos) != byte_count)
417			error("write error");
418		body_len -= byte_count;
419		eat(byte_count);
420		return 1;
421	}
422}
423
424static int __init do_symlink(void)
425{
426	collected[N_ALIGN(name_len) + body_len] = '\0';
427	clean_path(collected, 0);
428	init_symlink(collected + N_ALIGN(name_len), collected);
429	init_chown(collected, uid, gid, AT_SYMLINK_NOFOLLOW);
430	do_utime(collected, mtime);
431	state = SkipIt;
432	next_state = Reset;
433	return 0;
434}
435
436static __initdata int (*actions[])(void) = {
437	[Start]		= do_start,
438	[Collect]	= do_collect,
439	[GotHeader]	= do_header,
440	[SkipIt]	= do_skip,
441	[GotName]	= do_name,
442	[CopyFile]	= do_copy,
443	[GotSymlink]	= do_symlink,
444	[Reset]		= do_reset,
445};
446
447static long __init write_buffer(char *buf, unsigned long len)
448{
449	byte_count = len;
450	victim = buf;
451
452	while (!actions[state]())
453		;
454	return len - byte_count;
455}
456
457static long __init flush_buffer(void *bufv, unsigned long len)
458{
459	char *buf = bufv;
460	long written;
461	long origLen = len;
462	if (message)
463		return -1;
464	while ((written = write_buffer(buf, len)) < len && !message) {
465		char c = buf[written];
466		if (c == '0') {
467			buf += written;
468			len -= written;
469			state = Start;
470		} else if (c == 0) {
471			buf += written;
472			len -= written;
473			state = Reset;
474		} else
475			error("junk within compressed archive");
476	}
477	return origLen;
478}
479
480static unsigned long my_inptr __initdata; /* index of next byte to be processed in inbuf */
481
482#include <linux/decompress/generic.h>
483
484static char * __init unpack_to_rootfs(char *buf, unsigned long len)
485{
486	long written;
487	decompress_fn decompress;
488	const char *compress_name;
489	static __initdata char msg_buf[64];
490
491	header_buf = kmalloc(110, GFP_KERNEL);
492	symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
493	name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
494
495	if (!header_buf || !symlink_buf || !name_buf)
496		panic_show_mem("can't allocate buffers");
497
498	state = Start;
499	this_header = 0;
500	message = NULL;
501	while (!message && len) {
502		loff_t saved_offset = this_header;
503		if (*buf == '0' && !(this_header & 3)) {
504			state = Start;
505			written = write_buffer(buf, len);
506			buf += written;
507			len -= written;
508			continue;
509		}
510		if (!*buf) {
511			buf++;
512			len--;
513			this_header++;
514			continue;
515		}
516		this_header = 0;
517		decompress = decompress_method(buf, len, &compress_name);
518		pr_debug("Detected %s compressed data\n", compress_name);
519		if (decompress) {
520			int res = decompress(buf, len, NULL, flush_buffer, NULL,
521				   &my_inptr, error);
522			if (res)
523				error("decompressor failed");
524		} else if (compress_name) {
525			if (!message) {
526				snprintf(msg_buf, sizeof msg_buf,
527					 "compression method %s not configured",
528					 compress_name);
529				message = msg_buf;
530			}
531		} else
532			error("invalid magic at start of compressed archive");
533		if (state != Reset)
534			error("junk at the end of compressed archive");
535		this_header = saved_offset + my_inptr;
536		buf += my_inptr;
537		len -= my_inptr;
538	}
539	dir_utime();
540	kfree(name_buf);
541	kfree(symlink_buf);
542	kfree(header_buf);
543	return message;
544}
545
546static int __initdata do_retain_initrd;
547
548static int __init retain_initrd_param(char *str)
549{
550	if (*str)
551		return 0;
552	do_retain_initrd = 1;
553	return 1;
554}
555__setup("retain_initrd", retain_initrd_param);
556
557#ifdef CONFIG_ARCH_HAS_KEEPINITRD
558static int __init keepinitrd_setup(char *__unused)
559{
560	do_retain_initrd = 1;
561	return 1;
562}
563__setup("keepinitrd", keepinitrd_setup);
564#endif
565
566static bool __initdata initramfs_async = true;
567static int __init initramfs_async_setup(char *str)
568{
569	return kstrtobool(str, &initramfs_async) == 0;
570}
571__setup("initramfs_async=", initramfs_async_setup);
572
573extern char __initramfs_start[];
574extern unsigned long __initramfs_size;
575#include <linux/initrd.h>
576#include <linux/kexec.h>
577
578static ssize_t raw_read(struct file *file, struct kobject *kobj,
579			struct bin_attribute *attr, char *buf,
580			loff_t pos, size_t count)
581{
582	memcpy(buf, attr->private + pos, count);
583	return count;
584}
585
586static BIN_ATTR(initrd, 0440, raw_read, NULL, 0);
587
588void __init reserve_initrd_mem(void)
589{
590	phys_addr_t start;
591	unsigned long size;
592
593	/* Ignore the virtul address computed during device tree parsing */
594	initrd_start = initrd_end = 0;
595
596	if (!phys_initrd_size)
597		return;
598	/*
599	 * Round the memory region to page boundaries as per free_initrd_mem()
600	 * This allows us to detect whether the pages overlapping the initrd
601	 * are in use, but more importantly, reserves the entire set of pages
602	 * as we don't want these pages allocated for other purposes.
603	 */
604	start = round_down(phys_initrd_start, PAGE_SIZE);
605	size = phys_initrd_size + (phys_initrd_start - start);
606	size = round_up(size, PAGE_SIZE);
607
608	if (!memblock_is_region_memory(start, size)) {
609		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
610		       (u64)start, size);
611		goto disable;
612	}
613
614	if (memblock_is_region_reserved(start, size)) {
615		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
616		       (u64)start, size);
617		goto disable;
618	}
619
620	memblock_reserve(start, size);
621	/* Now convert initrd to virtual addresses */
622	initrd_start = (unsigned long)__va(phys_initrd_start);
623	initrd_end = initrd_start + phys_initrd_size;
624	initrd_below_start_ok = 1;
625
626	return;
627disable:
628	pr_cont(" - disabling initrd\n");
629	initrd_start = 0;
630	initrd_end = 0;
631}
632
633void __weak __init free_initrd_mem(unsigned long start, unsigned long end)
634{
635#ifdef CONFIG_ARCH_KEEP_MEMBLOCK
636	unsigned long aligned_start = ALIGN_DOWN(start, PAGE_SIZE);
637	unsigned long aligned_end = ALIGN(end, PAGE_SIZE);
638
639	memblock_free((void *)aligned_start, aligned_end - aligned_start);
640#endif
641
642	free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
643			"initrd");
644}
645
646#ifdef CONFIG_CRASH_RESERVE
647static bool __init kexec_free_initrd(void)
648{
 
649	unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
650	unsigned long crashk_end   = (unsigned long)__va(crashk_res.end);
 
 
 
651
 
652	/*
653	 * If the initrd region is overlapped with crashkernel reserved region,
654	 * free only memory that is not part of crashkernel region.
655	 */
656	if (initrd_start >= crashk_end || initrd_end <= crashk_start)
657		return false;
658
659	/*
660	 * Initialize initrd memory region since the kexec boot does not do.
661	 */
662	memset((void *)initrd_start, 0, initrd_end - initrd_start);
663	if (initrd_start < crashk_start)
664		free_initrd_mem(initrd_start, crashk_start);
665	if (initrd_end > crashk_end)
666		free_initrd_mem(crashk_end, initrd_end);
667	return true;
 
 
 
 
668}
669#else
670static inline bool kexec_free_initrd(void)
671{
672	return false;
673}
674#endif /* CONFIG_KEXEC_CORE */
675
676#ifdef CONFIG_BLK_DEV_RAM
677static void __init populate_initrd_image(char *err)
 
678{
679	ssize_t written;
680	struct file *file;
681	loff_t pos = 0;
682
683	printk(KERN_INFO "rootfs image is not initramfs (%s); looks like an initrd\n",
684			err);
685	file = filp_open("/initrd.image", O_WRONLY|O_CREAT|O_LARGEFILE, 0700);
686	if (IS_ERR(file))
 
 
 
 
 
687		return;
 
688
689	written = xwrite(file, (char *)initrd_start, initrd_end - initrd_start,
690			&pos);
691	if (written != initrd_end - initrd_start)
692		pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
693		       written, initrd_end - initrd_start);
694	fput(file);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
695}
696#endif /* CONFIG_BLK_DEV_RAM */
697
698static void __init do_populate_rootfs(void *unused, async_cookie_t cookie)
699{
700	/* Load the built in initramfs */
701	char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
702	if (err)
703		panic_show_mem("%s", err); /* Failed to decompress INTERNAL initramfs */
704
705	if (!initrd_start || IS_ENABLED(CONFIG_INITRAMFS_FORCE))
706		goto done;
707
708	if (IS_ENABLED(CONFIG_BLK_DEV_RAM))
709		printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
710	else
711		printk(KERN_INFO "Unpacking initramfs...\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
712
713	err = unpack_to_rootfs((char *)initrd_start, initrd_end - initrd_start);
714	if (err) {
715#ifdef CONFIG_BLK_DEV_RAM
716		populate_initrd_image(err);
717#else
718		printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
 
 
 
 
 
719#endif
720	}
721
722done:
723	/*
724	 * If the initrd region is overlapped with crashkernel reserved region,
725	 * free only memory that is not part of crashkernel region.
726	 */
727	if (!do_retain_initrd && initrd_start && !kexec_free_initrd()) {
728		free_initrd_mem(initrd_start, initrd_end);
729	} else if (do_retain_initrd && initrd_start) {
730		bin_attr_initrd.size = initrd_end - initrd_start;
731		bin_attr_initrd.private = (void *)initrd_start;
732		if (sysfs_create_bin_file(firmware_kobj, &bin_attr_initrd))
733			pr_err("Failed to create initrd sysfs file");
734	}
735	initrd_start = 0;
736	initrd_end = 0;
737
738	init_flush_fput();
739}
740
741static ASYNC_DOMAIN_EXCLUSIVE(initramfs_domain);
742static async_cookie_t initramfs_cookie;
743
744void wait_for_initramfs(void)
745{
746	if (!initramfs_cookie) {
747		/*
748		 * Something before rootfs_initcall wants to access
749		 * the filesystem/initramfs. Probably a bug. Make a
750		 * note, avoid deadlocking the machine, and let the
751		 * caller's access fail as it used to.
752		 */
753		pr_warn_once("wait_for_initramfs() called before rootfs_initcalls\n");
754		return;
755	}
756	async_synchronize_cookie_domain(initramfs_cookie + 1, &initramfs_domain);
757}
758EXPORT_SYMBOL_GPL(wait_for_initramfs);
759
760static int __init populate_rootfs(void)
761{
762	initramfs_cookie = async_schedule_domain(do_populate_rootfs, NULL,
763						 &initramfs_domain);
764	usermodehelper_enable();
765	if (!initramfs_async)
766		wait_for_initramfs();
767	return 0;
768}
769rootfs_initcall(populate_rootfs);