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