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