1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/init.h>
4 #include <linux/slab.h>
5 #include <linux/types.h>
6 #include <linux/fcntl.h>
7 #include <linux/delay.h>
8 #include <linux/string.h>
9 #include <linux/dirent.h>
10 #include <linux/syscalls.h>
11 #include <linux/utime.h>
12 #include <linux/file.h>
13 #include <linux/memblock.h>
15 #include <linux/namei.h>
16 #include <linux/init_syscalls.h>
18 static ssize_t __init
xwrite(struct file
*file
, const char *p
, size_t count
,
23 /* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */
25 ssize_t rv
= kernel_write(file
, p
, count
, pos
);
28 if (rv
== -EINTR
|| rv
== -EAGAIN
)
30 return out
? out
: rv
;
42 static __initdata
char *message
;
43 static void __init
error(char *x
)
49 static void panic_show_mem(const char *fmt
, ...)
61 #define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
63 static __initdata
struct hash
{
64 int ino
, minor
, major
;
67 char name
[N_ALIGN(PATH_MAX
)];
70 static inline int hash(int major
, int minor
, int ino
)
72 unsigned long tmp
= ino
+ minor
+ (major
<< 3);
77 static char __init
*find_link(int major
, int minor
, int ino
,
78 umode_t mode
, char *name
)
81 for (p
= head
+ hash(major
, minor
, ino
); *p
; p
= &(*p
)->next
) {
84 if ((*p
)->minor
!= minor
)
86 if ((*p
)->major
!= major
)
88 if (((*p
)->mode
^ mode
) & S_IFMT
)
92 q
= kmalloc(sizeof(struct hash
), GFP_KERNEL
);
94 panic_show_mem("can't allocate link hash entry");
99 strcpy(q
->name
, name
);
105 static void __init
free_hash(void)
108 for (p
= head
; p
< head
+ 32; p
++) {
117 static long __init
do_utime(char *filename
, time64_t mtime
)
119 struct timespec64 t
[2];
125 return init_utimes(filename
, t
);
128 static __initdata
LIST_HEAD(dir_list
);
130 struct list_head list
;
135 static void __init
dir_add(const char *name
, time64_t mtime
)
137 struct dir_entry
*de
= kmalloc(sizeof(struct dir_entry
), GFP_KERNEL
);
139 panic_show_mem("can't allocate dir_entry buffer");
140 INIT_LIST_HEAD(&de
->list
);
141 de
->name
= kstrdup(name
, GFP_KERNEL
);
143 list_add(&de
->list
, &dir_list
);
146 static void __init
dir_utime(void)
148 struct dir_entry
*de
, *tmp
;
149 list_for_each_entry_safe(de
, tmp
, &dir_list
, list
) {
151 do_utime(de
->name
, de
->mtime
);
157 static __initdata time64_t mtime
;
159 /* cpio header parsing */
161 static __initdata
unsigned long ino
, major
, minor
, nlink
;
162 static __initdata umode_t mode
;
163 static __initdata
unsigned long body_len
, name_len
;
164 static __initdata uid_t uid
;
165 static __initdata gid_t gid
;
166 static __initdata
unsigned rdev
;
168 static void __init
parse_header(char *s
)
170 unsigned long parsed
[12];
175 for (i
= 0, s
+= 6; i
< 12; i
++, s
+= 8) {
177 parsed
[i
] = simple_strtoul(buf
, NULL
, 16);
184 mtime
= parsed
[5]; /* breaks in y2106 */
185 body_len
= parsed
[6];
188 rdev
= new_encode_dev(MKDEV(parsed
[9], parsed
[10]));
189 name_len
= parsed
[11];
194 static __initdata
enum state
{
205 static __initdata
char *victim
;
206 static unsigned long byte_count __initdata
;
207 static __initdata loff_t this_header
, next_header
;
209 static inline void __init
eat(unsigned n
)
216 static __initdata
char *collected
;
217 static long remains __initdata
;
218 static __initdata
char *collect
;
220 static void __init
read_into(char *buf
, unsigned size
, enum state next
)
222 if (byte_count
>= size
) {
227 collect
= collected
= buf
;
234 static __initdata
char *header_buf
, *symlink_buf
, *name_buf
;
236 static int __init
do_start(void)
238 read_into(header_buf
, 110, GotHeader
);
242 static int __init
do_collect(void)
244 unsigned long n
= remains
;
247 memcpy(collect
, victim
, n
);
250 if ((remains
-= n
) != 0)
256 static int __init
do_header(void)
258 if (memcmp(collected
, "070707", 6)==0) {
259 error("incorrect cpio method used: use -H newc option");
262 if (memcmp(collected
, "070701", 6)) {
263 error("no cpio magic");
266 parse_header(collected
);
267 next_header
= this_header
+ N_ALIGN(name_len
) + body_len
;
268 next_header
= (next_header
+ 3) & ~3;
270 if (name_len
<= 0 || name_len
> PATH_MAX
)
273 if (body_len
> PATH_MAX
)
275 collect
= collected
= symlink_buf
;
276 remains
= N_ALIGN(name_len
) + body_len
;
277 next_state
= GotSymlink
;
281 if (S_ISREG(mode
) || !body_len
)
282 read_into(name_buf
, N_ALIGN(name_len
), GotName
);
286 static int __init
do_skip(void)
288 if (this_header
+ byte_count
< next_header
) {
292 eat(next_header
- this_header
);
298 static int __init
do_reset(void)
300 while (byte_count
&& *victim
== '\0')
302 if (byte_count
&& (this_header
& 3))
303 error("broken padding");
307 static void __init
clean_path(char *path
, umode_t fmode
)
311 if (!init_stat(path
, &st
, AT_SYMLINK_NOFOLLOW
) &&
312 (st
.mode
^ fmode
) & S_IFMT
) {
313 if (S_ISDIR(st
.mode
))
320 static int __init
maybe_link(void)
323 char *old
= find_link(major
, minor
, ino
, mode
, collected
);
325 clean_path(collected
, 0);
326 return (init_link(old
, collected
) < 0) ? -1 : 1;
332 static __initdata
struct file
*wfile
;
333 static __initdata loff_t wfile_pos
;
335 static int __init
do_name(void)
339 if (strcmp(collected
, "TRAILER!!!") == 0) {
343 clean_path(collected
, mode
);
345 int ml
= maybe_link();
347 int openflags
= O_WRONLY
|O_CREAT
;
349 openflags
|= O_TRUNC
;
350 wfile
= filp_open(collected
, openflags
, mode
);
355 vfs_fchown(wfile
, uid
, gid
);
356 vfs_fchmod(wfile
, mode
);
358 vfs_truncate(&wfile
->f_path
, body_len
);
361 } else if (S_ISDIR(mode
)) {
362 init_mkdir(collected
, mode
);
363 init_chown(collected
, uid
, gid
, 0);
364 init_chmod(collected
, mode
);
365 dir_add(collected
, mtime
);
366 } else if (S_ISBLK(mode
) || S_ISCHR(mode
) ||
367 S_ISFIFO(mode
) || S_ISSOCK(mode
)) {
368 if (maybe_link() == 0) {
369 init_mknod(collected
, mode
, rdev
);
370 init_chown(collected
, uid
, gid
, 0);
371 init_chmod(collected
, mode
);
372 do_utime(collected
, mtime
);
378 static int __init
do_copy(void)
380 if (byte_count
>= body_len
) {
381 struct timespec64 t
[2] = { };
382 if (xwrite(wfile
, victim
, body_len
, &wfile_pos
) != body_len
)
383 error("write error");
387 vfs_utimes(&wfile
->f_path
, t
);
394 if (xwrite(wfile
, victim
, byte_count
, &wfile_pos
) != byte_count
)
395 error("write error");
396 body_len
-= byte_count
;
402 static int __init
do_symlink(void)
404 collected
[N_ALIGN(name_len
) + body_len
] = '\0';
405 clean_path(collected
, 0);
406 init_symlink(collected
+ N_ALIGN(name_len
), collected
);
407 init_chown(collected
, uid
, gid
, AT_SYMLINK_NOFOLLOW
);
408 do_utime(collected
, mtime
);
414 static __initdata
int (*actions
[])(void) = {
416 [Collect
] = do_collect
,
417 [GotHeader
] = do_header
,
420 [CopyFile
] = do_copy
,
421 [GotSymlink
] = do_symlink
,
425 static long __init
write_buffer(char *buf
, unsigned long len
)
430 while (!actions
[state
]())
432 return len
- byte_count
;
435 static long __init
flush_buffer(void *bufv
, unsigned long len
)
437 char *buf
= (char *) bufv
;
442 while ((written
= write_buffer(buf
, len
)) < len
&& !message
) {
443 char c
= buf
[written
];
453 error("junk within compressed archive");
458 static unsigned long my_inptr
; /* index of next byte to be processed in inbuf */
460 #include <linux/decompress/generic.h>
462 static char * __init
unpack_to_rootfs(char *buf
, unsigned long len
)
465 decompress_fn decompress
;
466 const char *compress_name
;
467 static __initdata
char msg_buf
[64];
469 header_buf
= kmalloc(110, GFP_KERNEL
);
470 symlink_buf
= kmalloc(PATH_MAX
+ N_ALIGN(PATH_MAX
) + 1, GFP_KERNEL
);
471 name_buf
= kmalloc(N_ALIGN(PATH_MAX
), GFP_KERNEL
);
473 if (!header_buf
|| !symlink_buf
|| !name_buf
)
474 panic_show_mem("can't allocate buffers");
479 while (!message
&& len
) {
480 loff_t saved_offset
= this_header
;
481 if (*buf
== '0' && !(this_header
& 3)) {
483 written
= write_buffer(buf
, len
);
495 decompress
= decompress_method(buf
, len
, &compress_name
);
496 pr_debug("Detected %s compressed data\n", compress_name
);
498 int res
= decompress(buf
, len
, NULL
, flush_buffer
, NULL
,
501 error("decompressor failed");
502 } else if (compress_name
) {
504 snprintf(msg_buf
, sizeof msg_buf
,
505 "compression method %s not configured",
510 error("invalid magic at start of compressed archive");
512 error("junk at the end of compressed archive");
513 this_header
= saved_offset
+ my_inptr
;
524 static int __initdata do_retain_initrd
;
526 static int __init
retain_initrd_param(char *str
)
530 do_retain_initrd
= 1;
533 __setup("retain_initrd", retain_initrd_param
);
535 #ifdef CONFIG_ARCH_HAS_KEEPINITRD
536 static int __init
keepinitrd_setup(char *__unused
)
538 do_retain_initrd
= 1;
541 __setup("keepinitrd", keepinitrd_setup
);
544 extern char __initramfs_start
[];
545 extern unsigned long __initramfs_size
;
546 #include <linux/initrd.h>
547 #include <linux/kexec.h>
549 void __init
reserve_initrd_mem(void)
554 /* Ignore the virtul address computed during device tree parsing */
555 initrd_start
= initrd_end
= 0;
557 if (!phys_initrd_size
)
560 * Round the memory region to page boundaries as per free_initrd_mem()
561 * This allows us to detect whether the pages overlapping the initrd
562 * are in use, but more importantly, reserves the entire set of pages
563 * as we don't want these pages allocated for other purposes.
565 start
= round_down(phys_initrd_start
, PAGE_SIZE
);
566 size
= phys_initrd_size
+ (phys_initrd_start
- start
);
567 size
= round_up(size
, PAGE_SIZE
);
569 if (!memblock_is_region_memory(start
, size
)) {
570 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
575 if (memblock_is_region_reserved(start
, size
)) {
576 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
581 memblock_reserve(start
, size
);
582 /* Now convert initrd to virtual addresses */
583 initrd_start
= (unsigned long)__va(phys_initrd_start
);
584 initrd_end
= initrd_start
+ phys_initrd_size
;
585 initrd_below_start_ok
= 1;
589 pr_cont(" - disabling initrd\n");
594 void __weak __init
free_initrd_mem(unsigned long start
, unsigned long end
)
596 #ifdef CONFIG_ARCH_KEEP_MEMBLOCK
597 unsigned long aligned_start
= ALIGN_DOWN(start
, PAGE_SIZE
);
598 unsigned long aligned_end
= ALIGN(end
, PAGE_SIZE
);
600 memblock_free(__pa(aligned_start
), aligned_end
- aligned_start
);
603 free_reserved_area((void *)start
, (void *)end
, POISON_FREE_INITMEM
,
607 #ifdef CONFIG_KEXEC_CORE
608 static bool __init
kexec_free_initrd(void)
610 unsigned long crashk_start
= (unsigned long)__va(crashk_res
.start
);
611 unsigned long crashk_end
= (unsigned long)__va(crashk_res
.end
);
614 * If the initrd region is overlapped with crashkernel reserved region,
615 * free only memory that is not part of crashkernel region.
617 if (initrd_start
>= crashk_end
|| initrd_end
<= crashk_start
)
621 * Initialize initrd memory region since the kexec boot does not do.
623 memset((void *)initrd_start
, 0, initrd_end
- initrd_start
);
624 if (initrd_start
< crashk_start
)
625 free_initrd_mem(initrd_start
, crashk_start
);
626 if (initrd_end
> crashk_end
)
627 free_initrd_mem(crashk_end
, initrd_end
);
631 static inline bool kexec_free_initrd(void)
635 #endif /* CONFIG_KEXEC_CORE */
637 #ifdef CONFIG_BLK_DEV_RAM
638 static void __init
populate_initrd_image(char *err
)
644 unpack_to_rootfs(__initramfs_start
, __initramfs_size
);
646 printk(KERN_INFO
"rootfs image is not initramfs (%s); looks like an initrd\n",
648 file
= filp_open("/initrd.image", O_WRONLY
| O_CREAT
, 0700);
652 written
= xwrite(file
, (char *)initrd_start
, initrd_end
- initrd_start
,
654 if (written
!= initrd_end
- initrd_start
)
655 pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
656 written
, initrd_end
- initrd_start
);
659 #endif /* CONFIG_BLK_DEV_RAM */
661 static int __init
populate_rootfs(void)
663 /* Load the built in initramfs */
664 char *err
= unpack_to_rootfs(__initramfs_start
, __initramfs_size
);
666 panic_show_mem("%s", err
); /* Failed to decompress INTERNAL initramfs */
668 if (!initrd_start
|| IS_ENABLED(CONFIG_INITRAMFS_FORCE
))
671 if (IS_ENABLED(CONFIG_BLK_DEV_RAM
))
672 printk(KERN_INFO
"Trying to unpack rootfs image as initramfs...\n");
674 printk(KERN_INFO
"Unpacking initramfs...\n");
676 err
= unpack_to_rootfs((char *)initrd_start
, initrd_end
- initrd_start
);
678 #ifdef CONFIG_BLK_DEV_RAM
679 populate_initrd_image(err
);
681 printk(KERN_EMERG
"Initramfs unpacking failed: %s\n", err
);
687 * If the initrd region is overlapped with crashkernel reserved region,
688 * free only memory that is not part of crashkernel region.
690 if (!do_retain_initrd
&& initrd_start
&& !kexec_free_initrd())
691 free_initrd_mem(initrd_start
, initrd_end
);
695 flush_delayed_fput();
698 rootfs_initcall(populate_rootfs
);