1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/init.h>
3 #include <linux/async.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>
17 #include <linux/namei.h>
18 #include <linux/init_syscalls.h>
19 #include <linux/umh.h>
21 #include "do_mounts.h"
23 static __initdata bool csum_present;
24 static __initdata u32 io_csum;
26 static ssize_t __init xwrite(struct file *file, const unsigned char *p,
27 size_t count, loff_t *pos)
31 /* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */
33 ssize_t rv = kernel_write(file, p, count, pos);
36 if (rv == -EINTR || rv == -EAGAIN)
38 return out ? out : rv;
45 for (i = 0; i < rv; i++)
57 static __initdata char *message;
58 static void __init error(char *x)
64 #define panic_show_mem(fmt, ...) \
65 ({ show_mem(); panic(fmt, ##__VA_ARGS__); })
69 #define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
71 static __initdata struct hash {
72 int ino, minor, major;
75 char name[N_ALIGN(PATH_MAX)];
78 static inline int hash(int major, int minor, int ino)
80 unsigned long tmp = ino + minor + (major << 3);
85 static char __init *find_link(int major, int minor, int ino,
86 umode_t mode, char *name)
89 for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
92 if ((*p)->minor != minor)
94 if ((*p)->major != major)
96 if (((*p)->mode ^ mode) & S_IFMT)
100 q = kmalloc(sizeof(struct hash), GFP_KERNEL);
102 panic_show_mem("can't allocate link hash entry");
107 strcpy(q->name, name);
113 static void __init free_hash(void)
116 for (p = head; p < head + 32; p++) {
125 #ifdef CONFIG_INITRAMFS_PRESERVE_MTIME
126 static void __init do_utime(char *filename, time64_t mtime)
128 struct timespec64 t[2] = { { .tv_sec = mtime }, { .tv_sec = mtime } };
129 init_utimes(filename, t);
132 static void __init do_utime_path(const struct path *path, time64_t mtime)
134 struct timespec64 t[2] = { { .tv_sec = mtime }, { .tv_sec = mtime } };
138 static __initdata LIST_HEAD(dir_list);
140 struct list_head list;
145 static void __init dir_add(const char *name, time64_t mtime)
147 size_t nlen = strlen(name) + 1;
148 struct dir_entry *de;
150 de = kmalloc(sizeof(struct dir_entry) + nlen, GFP_KERNEL);
152 panic_show_mem("can't allocate dir_entry buffer");
153 INIT_LIST_HEAD(&de->list);
154 strscpy(de->name, name, nlen);
156 list_add(&de->list, &dir_list);
159 static void __init dir_utime(void)
161 struct dir_entry *de, *tmp;
162 list_for_each_entry_safe(de, tmp, &dir_list, list) {
164 do_utime(de->name, de->mtime);
169 static void __init do_utime(char *filename, time64_t mtime) {}
170 static void __init do_utime_path(const struct path *path, time64_t mtime) {}
171 static void __init dir_add(const char *name, time64_t mtime) {}
172 static void __init dir_utime(void) {}
175 static __initdata time64_t mtime;
177 /* cpio header parsing */
179 static __initdata unsigned long ino, major, minor, nlink;
180 static __initdata umode_t mode;
181 static __initdata unsigned long body_len, name_len;
182 static __initdata uid_t uid;
183 static __initdata gid_t gid;
184 static __initdata unsigned rdev;
185 static __initdata u32 hdr_csum;
187 static void __init parse_header(char *s)
189 unsigned long parsed[13];
194 for (i = 0, s += 6; i < 13; i++, s += 8) {
196 parsed[i] = simple_strtoul(buf, NULL, 16);
203 mtime = parsed[5]; /* breaks in y2106 */
204 body_len = parsed[6];
207 rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
208 name_len = parsed[11];
209 hdr_csum = parsed[12];
214 static __initdata enum state {
225 static __initdata char *victim;
226 static unsigned long byte_count __initdata;
227 static __initdata loff_t this_header, next_header;
229 static inline void __init eat(unsigned n)
236 static __initdata char *collected;
237 static long remains __initdata;
238 static __initdata char *collect;
240 static void __init read_into(char *buf, unsigned size, enum state next)
242 if (byte_count >= size) {
247 collect = collected = buf;
254 static __initdata char *header_buf, *symlink_buf, *name_buf;
256 static int __init do_start(void)
258 read_into(header_buf, 110, GotHeader);
262 static int __init do_collect(void)
264 unsigned long n = remains;
267 memcpy(collect, victim, n);
270 if ((remains -= n) != 0)
276 static int __init do_header(void)
278 if (!memcmp(collected, "070701", 6)) {
279 csum_present = false;
280 } else if (!memcmp(collected, "070702", 6)) {
283 if (memcmp(collected, "070707", 6) == 0)
284 error("incorrect cpio method used: use -H newc option");
286 error("no cpio magic");
289 parse_header(collected);
290 next_header = this_header + N_ALIGN(name_len) + body_len;
291 next_header = (next_header + 3) & ~3;
293 if (name_len <= 0 || name_len > PATH_MAX)
296 if (body_len > PATH_MAX)
298 collect = collected = symlink_buf;
299 remains = N_ALIGN(name_len) + body_len;
300 next_state = GotSymlink;
304 if (S_ISREG(mode) || !body_len)
305 read_into(name_buf, N_ALIGN(name_len), GotName);
309 static int __init do_skip(void)
311 if (this_header + byte_count < next_header) {
315 eat(next_header - this_header);
321 static int __init do_reset(void)
323 while (byte_count && *victim == '\0')
325 if (byte_count && (this_header & 3))
326 error("broken padding");
330 static void __init clean_path(char *path, umode_t fmode)
334 if (!init_stat(path, &st, AT_SYMLINK_NOFOLLOW) &&
335 (st.mode ^ fmode) & S_IFMT) {
336 if (S_ISDIR(st.mode))
343 static int __init maybe_link(void)
346 char *old = find_link(major, minor, ino, mode, collected);
348 clean_path(collected, 0);
349 return (init_link(old, collected) < 0) ? -1 : 1;
355 static __initdata struct file *wfile;
356 static __initdata loff_t wfile_pos;
358 static int __init do_name(void)
362 if (strcmp(collected, "TRAILER!!!") == 0) {
366 clean_path(collected, mode);
368 int ml = maybe_link();
370 int openflags = O_WRONLY|O_CREAT;
372 openflags |= O_TRUNC;
373 wfile = filp_open(collected, openflags, mode);
379 vfs_fchown(wfile, uid, gid);
380 vfs_fchmod(wfile, mode);
382 vfs_truncate(&wfile->f_path, body_len);
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);
402 static int __init do_copy(void)
404 if (byte_count >= body_len) {
405 if (xwrite(wfile, victim, body_len, &wfile_pos) != body_len)
406 error("write error");
408 do_utime_path(&wfile->f_path, mtime);
410 if (csum_present && io_csum != hdr_csum)
411 error("bad data checksum");
416 if (xwrite(wfile, victim, byte_count, &wfile_pos) != byte_count)
417 error("write error");
418 body_len -= byte_count;
424 static int __init do_symlink(void)
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);
436 static __initdata int (*actions[])(void) = {
438 [Collect] = do_collect,
439 [GotHeader] = do_header,
442 [CopyFile] = do_copy,
443 [GotSymlink] = do_symlink,
447 static long __init write_buffer(char *buf, unsigned long len)
452 while (!actions[state]())
454 return len - byte_count;
457 static long __init flush_buffer(void *bufv, unsigned long len)
464 while ((written = write_buffer(buf, len)) < len && !message) {
465 char c = buf[written];
475 error("junk within compressed archive");
480 static unsigned long my_inptr __initdata; /* index of next byte to be processed in inbuf */
482 #include <linux/decompress/generic.h>
484 static char * __init unpack_to_rootfs(char *buf, unsigned long len)
487 decompress_fn decompress;
488 const char *compress_name;
489 static __initdata char msg_buf[64];
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);
495 if (!header_buf || !symlink_buf || !name_buf)
496 panic_show_mem("can't allocate buffers");
501 while (!message && len) {
502 loff_t saved_offset = this_header;
503 if (*buf == '0' && !(this_header & 3)) {
505 written = write_buffer(buf, len);
517 decompress = decompress_method(buf, len, &compress_name);
518 pr_debug("Detected %s compressed data\n", compress_name);
520 int res = decompress(buf, len, NULL, flush_buffer, NULL,
523 error("decompressor failed");
524 } else if (compress_name) {
526 snprintf(msg_buf, sizeof msg_buf,
527 "compression method %s not configured",
532 error("invalid magic at start of compressed archive");
534 error("junk at the end of compressed archive");
535 this_header = saved_offset + my_inptr;
546 static int __initdata do_retain_initrd;
548 static int __init retain_initrd_param(char *str)
552 do_retain_initrd = 1;
555 __setup("retain_initrd", retain_initrd_param);
557 #ifdef CONFIG_ARCH_HAS_KEEPINITRD
558 static int __init keepinitrd_setup(char *__unused)
560 do_retain_initrd = 1;
563 __setup("keepinitrd", keepinitrd_setup);
566 static bool __initdata initramfs_async = true;
567 static int __init initramfs_async_setup(char *str)
569 return kstrtobool(str, &initramfs_async) == 0;
571 __setup("initramfs_async=", initramfs_async_setup);
573 extern char __initramfs_start[];
574 extern unsigned long __initramfs_size;
575 #include <linux/initrd.h>
576 #include <linux/kexec.h>
578 static ssize_t raw_read(struct file *file, struct kobject *kobj,
579 struct bin_attribute *attr, char *buf,
580 loff_t pos, size_t count)
582 memcpy(buf, attr->private + pos, count);
586 static BIN_ATTR(initrd, 0440, raw_read, NULL, 0);
588 void __init reserve_initrd_mem(void)
593 /* Ignore the virtul address computed during device tree parsing */
594 initrd_start = initrd_end = 0;
596 if (!phys_initrd_size)
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.
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);
608 if (!memblock_is_region_memory(start, size)) {
609 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
614 if (memblock_is_region_reserved(start, size)) {
615 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
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;
628 pr_cont(" - disabling initrd\n");
633 void __weak __init free_initrd_mem(unsigned long start, unsigned long end)
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);
639 memblock_free((void *)aligned_start, aligned_end - aligned_start);
642 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
646 #ifdef CONFIG_CRASH_RESERVE
647 static bool __init kexec_free_initrd(void)
649 unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
650 unsigned long crashk_end = (unsigned long)__va(crashk_res.end);
653 * If the initrd region is overlapped with crashkernel reserved region,
654 * free only memory that is not part of crashkernel region.
656 if (initrd_start >= crashk_end || initrd_end <= crashk_start)
660 * Initialize initrd memory region since the kexec boot does not do.
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);
670 static inline bool kexec_free_initrd(void)
674 #endif /* CONFIG_KEXEC_CORE */
676 #ifdef CONFIG_BLK_DEV_RAM
677 static void __init populate_initrd_image(char *err)
683 printk(KERN_INFO "rootfs image is not initramfs (%s); looks like an initrd\n",
685 file = filp_open("/initrd.image", O_WRONLY | O_CREAT, 0700);
689 written = xwrite(file, (char *)initrd_start, initrd_end - initrd_start,
691 if (written != initrd_end - initrd_start)
692 pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
693 written, initrd_end - initrd_start);
696 #endif /* CONFIG_BLK_DEV_RAM */
698 static void __init do_populate_rootfs(void *unused, async_cookie_t cookie)
700 /* Load the built in initramfs */
701 char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
703 panic_show_mem("%s", err); /* Failed to decompress INTERNAL initramfs */
705 if (!initrd_start || IS_ENABLED(CONFIG_INITRAMFS_FORCE))
708 if (IS_ENABLED(CONFIG_BLK_DEV_RAM))
709 printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
711 printk(KERN_INFO "Unpacking initramfs...\n");
713 err = unpack_to_rootfs((char *)initrd_start, initrd_end - initrd_start);
715 #ifdef CONFIG_BLK_DEV_RAM
716 populate_initrd_image(err);
718 printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
724 * If the initrd region is overlapped with crashkernel reserved region,
725 * free only memory that is not part of crashkernel region.
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");
741 static ASYNC_DOMAIN_EXCLUSIVE(initramfs_domain);
742 static async_cookie_t initramfs_cookie;
744 void wait_for_initramfs(void)
746 if (!initramfs_cookie) {
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.
753 pr_warn_once("wait_for_initramfs() called before rootfs_initcalls\n");
756 async_synchronize_cookie_domain(initramfs_cookie + 1, &initramfs_domain);
758 EXPORT_SYMBOL_GPL(wait_for_initramfs);
760 static int __init populate_rootfs(void)
762 initramfs_cookie = async_schedule_domain(do_populate_rootfs, NULL,
764 usermodehelper_enable();
765 if (!initramfs_async)
766 wait_for_initramfs();
769 rootfs_initcall(populate_rootfs);