mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 01:10:04 +00:00
![Nicolas Schier](/assets/img/avatar_default.png)
Cpio format reserves 8 bytes for an ASCII representation of a time_t timestamp. While 2106-02-07 06:28:15 UTC (time_t = 0xffffffff) is still some years in the future, a poorly chosen date string for KBUILD_BUILD_TIMESTAMP, converted into seconds since the epoch, might lead to exceeded cpio timestamp limits that result in a broken cpio archive. Add timestamp checks to prevent overrun of the 8-byte cpio header field. My colleague Thomas Kühnel discovered the behaviour, when we accidentally fed SOURCE_DATE_EPOCH to KBUILD_BUILD_TIMESTAMP as is: some timestamps (e.g. 1607420928 = 2021-12-08 9:48:48 UTC) will be interpreted by `date` as a valid date specification of science fictional times (here: year 160742). Even though this is bad input for KBUILD_BUILD_TIMESTAMP, it should not break the initramfs cpio format. Signed-off-by: Nicolas Schier <nicolas@fjasle.eu> Cc: Thomas Kühnel <thomas.kuehnel@avm.de> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
640 lines
13 KiB
C
640 lines
13 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <time.h>
|
|
#include <fcntl.h>
|
|
#include <errno.h>
|
|
#include <ctype.h>
|
|
#include <limits.h>
|
|
|
|
/*
|
|
* Original work by Jeff Garzik
|
|
*
|
|
* External file lists, symlink, pipe and fifo support by Thayne Harbaugh
|
|
* Hard link support by Luciano Rocha
|
|
*/
|
|
|
|
#define xstr(s) #s
|
|
#define str(s) xstr(s)
|
|
|
|
static unsigned int offset;
|
|
static unsigned int ino = 721;
|
|
static time_t default_mtime;
|
|
|
|
struct file_handler {
|
|
const char *type;
|
|
int (*handler)(const char *line);
|
|
};
|
|
|
|
static void push_string(const char *name)
|
|
{
|
|
unsigned int name_len = strlen(name) + 1;
|
|
|
|
fputs(name, stdout);
|
|
putchar(0);
|
|
offset += name_len;
|
|
}
|
|
|
|
static void push_pad (void)
|
|
{
|
|
while (offset & 3) {
|
|
putchar(0);
|
|
offset++;
|
|
}
|
|
}
|
|
|
|
static void push_rest(const char *name)
|
|
{
|
|
unsigned int name_len = strlen(name) + 1;
|
|
unsigned int tmp_ofs;
|
|
|
|
fputs(name, stdout);
|
|
putchar(0);
|
|
offset += name_len;
|
|
|
|
tmp_ofs = name_len + 110;
|
|
while (tmp_ofs & 3) {
|
|
putchar(0);
|
|
offset++;
|
|
tmp_ofs++;
|
|
}
|
|
}
|
|
|
|
static void push_hdr(const char *s)
|
|
{
|
|
fputs(s, stdout);
|
|
offset += 110;
|
|
}
|
|
|
|
static void cpio_trailer(void)
|
|
{
|
|
char s[256];
|
|
const char name[] = "TRAILER!!!";
|
|
|
|
sprintf(s, "%s%08X%08X%08lX%08lX%08X%08lX"
|
|
"%08X%08X%08X%08X%08X%08X%08X",
|
|
"070701", /* magic */
|
|
0, /* ino */
|
|
0, /* mode */
|
|
(long) 0, /* uid */
|
|
(long) 0, /* gid */
|
|
1, /* nlink */
|
|
(long) 0, /* mtime */
|
|
0, /* filesize */
|
|
0, /* major */
|
|
0, /* minor */
|
|
0, /* rmajor */
|
|
0, /* rminor */
|
|
(unsigned)strlen(name)+1, /* namesize */
|
|
0); /* chksum */
|
|
push_hdr(s);
|
|
push_rest(name);
|
|
|
|
while (offset % 512) {
|
|
putchar(0);
|
|
offset++;
|
|
}
|
|
}
|
|
|
|
static int cpio_mkslink(const char *name, const char *target,
|
|
unsigned int mode, uid_t uid, gid_t gid)
|
|
{
|
|
char s[256];
|
|
|
|
if (name[0] == '/')
|
|
name++;
|
|
sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
|
|
"%08X%08X%08X%08X%08X%08X%08X",
|
|
"070701", /* magic */
|
|
ino++, /* ino */
|
|
S_IFLNK | mode, /* mode */
|
|
(long) uid, /* uid */
|
|
(long) gid, /* gid */
|
|
1, /* nlink */
|
|
(long) default_mtime, /* mtime */
|
|
(unsigned)strlen(target)+1, /* filesize */
|
|
3, /* major */
|
|
1, /* minor */
|
|
0, /* rmajor */
|
|
0, /* rminor */
|
|
(unsigned)strlen(name) + 1,/* namesize */
|
|
0); /* chksum */
|
|
push_hdr(s);
|
|
push_string(name);
|
|
push_pad();
|
|
push_string(target);
|
|
push_pad();
|
|
return 0;
|
|
}
|
|
|
|
static int cpio_mkslink_line(const char *line)
|
|
{
|
|
char name[PATH_MAX + 1];
|
|
char target[PATH_MAX + 1];
|
|
unsigned int mode;
|
|
int uid;
|
|
int gid;
|
|
int rc = -1;
|
|
|
|
if (5 != sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) "s %o %d %d", name, target, &mode, &uid, &gid)) {
|
|
fprintf(stderr, "Unrecognized dir format '%s'", line);
|
|
goto fail;
|
|
}
|
|
rc = cpio_mkslink(name, target, mode, uid, gid);
|
|
fail:
|
|
return rc;
|
|
}
|
|
|
|
static int cpio_mkgeneric(const char *name, unsigned int mode,
|
|
uid_t uid, gid_t gid)
|
|
{
|
|
char s[256];
|
|
|
|
if (name[0] == '/')
|
|
name++;
|
|
sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
|
|
"%08X%08X%08X%08X%08X%08X%08X",
|
|
"070701", /* magic */
|
|
ino++, /* ino */
|
|
mode, /* mode */
|
|
(long) uid, /* uid */
|
|
(long) gid, /* gid */
|
|
2, /* nlink */
|
|
(long) default_mtime, /* mtime */
|
|
0, /* filesize */
|
|
3, /* major */
|
|
1, /* minor */
|
|
0, /* rmajor */
|
|
0, /* rminor */
|
|
(unsigned)strlen(name) + 1,/* namesize */
|
|
0); /* chksum */
|
|
push_hdr(s);
|
|
push_rest(name);
|
|
return 0;
|
|
}
|
|
|
|
enum generic_types {
|
|
GT_DIR,
|
|
GT_PIPE,
|
|
GT_SOCK
|
|
};
|
|
|
|
struct generic_type {
|
|
const char *type;
|
|
mode_t mode;
|
|
};
|
|
|
|
static const struct generic_type generic_type_table[] = {
|
|
[GT_DIR] = {
|
|
.type = "dir",
|
|
.mode = S_IFDIR
|
|
},
|
|
[GT_PIPE] = {
|
|
.type = "pipe",
|
|
.mode = S_IFIFO
|
|
},
|
|
[GT_SOCK] = {
|
|
.type = "sock",
|
|
.mode = S_IFSOCK
|
|
}
|
|
};
|
|
|
|
static int cpio_mkgeneric_line(const char *line, enum generic_types gt)
|
|
{
|
|
char name[PATH_MAX + 1];
|
|
unsigned int mode;
|
|
int uid;
|
|
int gid;
|
|
int rc = -1;
|
|
|
|
if (4 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d", name, &mode, &uid, &gid)) {
|
|
fprintf(stderr, "Unrecognized %s format '%s'",
|
|
line, generic_type_table[gt].type);
|
|
goto fail;
|
|
}
|
|
mode |= generic_type_table[gt].mode;
|
|
rc = cpio_mkgeneric(name, mode, uid, gid);
|
|
fail:
|
|
return rc;
|
|
}
|
|
|
|
static int cpio_mkdir_line(const char *line)
|
|
{
|
|
return cpio_mkgeneric_line(line, GT_DIR);
|
|
}
|
|
|
|
static int cpio_mkpipe_line(const char *line)
|
|
{
|
|
return cpio_mkgeneric_line(line, GT_PIPE);
|
|
}
|
|
|
|
static int cpio_mksock_line(const char *line)
|
|
{
|
|
return cpio_mkgeneric_line(line, GT_SOCK);
|
|
}
|
|
|
|
static int cpio_mknod(const char *name, unsigned int mode,
|
|
uid_t uid, gid_t gid, char dev_type,
|
|
unsigned int maj, unsigned int min)
|
|
{
|
|
char s[256];
|
|
|
|
if (dev_type == 'b')
|
|
mode |= S_IFBLK;
|
|
else
|
|
mode |= S_IFCHR;
|
|
|
|
if (name[0] == '/')
|
|
name++;
|
|
sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
|
|
"%08X%08X%08X%08X%08X%08X%08X",
|
|
"070701", /* magic */
|
|
ino++, /* ino */
|
|
mode, /* mode */
|
|
(long) uid, /* uid */
|
|
(long) gid, /* gid */
|
|
1, /* nlink */
|
|
(long) default_mtime, /* mtime */
|
|
0, /* filesize */
|
|
3, /* major */
|
|
1, /* minor */
|
|
maj, /* rmajor */
|
|
min, /* rminor */
|
|
(unsigned)strlen(name) + 1,/* namesize */
|
|
0); /* chksum */
|
|
push_hdr(s);
|
|
push_rest(name);
|
|
return 0;
|
|
}
|
|
|
|
static int cpio_mknod_line(const char *line)
|
|
{
|
|
char name[PATH_MAX + 1];
|
|
unsigned int mode;
|
|
int uid;
|
|
int gid;
|
|
char dev_type;
|
|
unsigned int maj;
|
|
unsigned int min;
|
|
int rc = -1;
|
|
|
|
if (7 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d %c %u %u",
|
|
name, &mode, &uid, &gid, &dev_type, &maj, &min)) {
|
|
fprintf(stderr, "Unrecognized nod format '%s'", line);
|
|
goto fail;
|
|
}
|
|
rc = cpio_mknod(name, mode, uid, gid, dev_type, maj, min);
|
|
fail:
|
|
return rc;
|
|
}
|
|
|
|
static int cpio_mkfile(const char *name, const char *location,
|
|
unsigned int mode, uid_t uid, gid_t gid,
|
|
unsigned int nlinks)
|
|
{
|
|
char s[256];
|
|
char *filebuf = NULL;
|
|
struct stat buf;
|
|
long size;
|
|
int file = -1;
|
|
int retval;
|
|
int rc = -1;
|
|
int namesize;
|
|
unsigned int i;
|
|
|
|
mode |= S_IFREG;
|
|
|
|
file = open (location, O_RDONLY);
|
|
if (file < 0) {
|
|
fprintf (stderr, "File %s could not be opened for reading\n", location);
|
|
goto error;
|
|
}
|
|
|
|
retval = fstat(file, &buf);
|
|
if (retval) {
|
|
fprintf(stderr, "File %s could not be stat()'ed\n", location);
|
|
goto error;
|
|
}
|
|
|
|
if (buf.st_mtime > 0xffffffff) {
|
|
fprintf(stderr, "%s: Timestamp exceeds maximum cpio timestamp, clipping.\n",
|
|
location);
|
|
buf.st_mtime = 0xffffffff;
|
|
}
|
|
|
|
filebuf = malloc(buf.st_size);
|
|
if (!filebuf) {
|
|
fprintf (stderr, "out of memory\n");
|
|
goto error;
|
|
}
|
|
|
|
retval = read (file, filebuf, buf.st_size);
|
|
if (retval < 0) {
|
|
fprintf (stderr, "Can not read %s file\n", location);
|
|
goto error;
|
|
}
|
|
|
|
size = 0;
|
|
for (i = 1; i <= nlinks; i++) {
|
|
/* data goes on last link */
|
|
if (i == nlinks) size = buf.st_size;
|
|
|
|
if (name[0] == '/')
|
|
name++;
|
|
namesize = strlen(name) + 1;
|
|
sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
|
|
"%08lX%08X%08X%08X%08X%08X%08X",
|
|
"070701", /* magic */
|
|
ino, /* ino */
|
|
mode, /* mode */
|
|
(long) uid, /* uid */
|
|
(long) gid, /* gid */
|
|
nlinks, /* nlink */
|
|
(long) buf.st_mtime, /* mtime */
|
|
size, /* filesize */
|
|
3, /* major */
|
|
1, /* minor */
|
|
0, /* rmajor */
|
|
0, /* rminor */
|
|
namesize, /* namesize */
|
|
0); /* chksum */
|
|
push_hdr(s);
|
|
push_string(name);
|
|
push_pad();
|
|
|
|
if (size) {
|
|
if (fwrite(filebuf, size, 1, stdout) != 1) {
|
|
fprintf(stderr, "writing filebuf failed\n");
|
|
goto error;
|
|
}
|
|
offset += size;
|
|
push_pad();
|
|
}
|
|
|
|
name += namesize;
|
|
}
|
|
ino++;
|
|
rc = 0;
|
|
|
|
error:
|
|
if (filebuf) free(filebuf);
|
|
if (file >= 0) close(file);
|
|
return rc;
|
|
}
|
|
|
|
static char *cpio_replace_env(char *new_location)
|
|
{
|
|
char expanded[PATH_MAX + 1];
|
|
char *start, *end, *var;
|
|
|
|
while ((start = strstr(new_location, "${")) &&
|
|
(end = strchr(start + 2, '}'))) {
|
|
*start = *end = 0;
|
|
var = getenv(start + 2);
|
|
snprintf(expanded, sizeof expanded, "%s%s%s",
|
|
new_location, var ? var : "", end + 1);
|
|
strcpy(new_location, expanded);
|
|
}
|
|
|
|
return new_location;
|
|
}
|
|
|
|
static int cpio_mkfile_line(const char *line)
|
|
{
|
|
char name[PATH_MAX + 1];
|
|
char *dname = NULL; /* malloc'ed buffer for hard links */
|
|
char location[PATH_MAX + 1];
|
|
unsigned int mode;
|
|
int uid;
|
|
int gid;
|
|
int nlinks = 1;
|
|
int end = 0, dname_len = 0;
|
|
int rc = -1;
|
|
|
|
if (5 > sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX)
|
|
"s %o %d %d %n",
|
|
name, location, &mode, &uid, &gid, &end)) {
|
|
fprintf(stderr, "Unrecognized file format '%s'", line);
|
|
goto fail;
|
|
}
|
|
if (end && isgraph(line[end])) {
|
|
int len;
|
|
int nend;
|
|
|
|
dname = malloc(strlen(line));
|
|
if (!dname) {
|
|
fprintf (stderr, "out of memory (%d)\n", dname_len);
|
|
goto fail;
|
|
}
|
|
|
|
dname_len = strlen(name) + 1;
|
|
memcpy(dname, name, dname_len);
|
|
|
|
do {
|
|
nend = 0;
|
|
if (sscanf(line + end, "%" str(PATH_MAX) "s %n",
|
|
name, &nend) < 1)
|
|
break;
|
|
len = strlen(name) + 1;
|
|
memcpy(dname + dname_len, name, len);
|
|
dname_len += len;
|
|
nlinks++;
|
|
end += nend;
|
|
} while (isgraph(line[end]));
|
|
} else {
|
|
dname = name;
|
|
}
|
|
rc = cpio_mkfile(dname, cpio_replace_env(location),
|
|
mode, uid, gid, nlinks);
|
|
fail:
|
|
if (dname_len) free(dname);
|
|
return rc;
|
|
}
|
|
|
|
static void usage(const char *prog)
|
|
{
|
|
fprintf(stderr, "Usage:\n"
|
|
"\t%s [-t <timestamp>] <cpio_list>\n"
|
|
"\n"
|
|
"<cpio_list> is a file containing newline separated entries that\n"
|
|
"describe the files to be included in the initramfs archive:\n"
|
|
"\n"
|
|
"# a comment\n"
|
|
"file <name> <location> <mode> <uid> <gid> [<hard links>]\n"
|
|
"dir <name> <mode> <uid> <gid>\n"
|
|
"nod <name> <mode> <uid> <gid> <dev_type> <maj> <min>\n"
|
|
"slink <name> <target> <mode> <uid> <gid>\n"
|
|
"pipe <name> <mode> <uid> <gid>\n"
|
|
"sock <name> <mode> <uid> <gid>\n"
|
|
"\n"
|
|
"<name> name of the file/dir/nod/etc in the archive\n"
|
|
"<location> location of the file in the current filesystem\n"
|
|
" expands shell variables quoted with ${}\n"
|
|
"<target> link target\n"
|
|
"<mode> mode/permissions of the file\n"
|
|
"<uid> user id (0=root)\n"
|
|
"<gid> group id (0=root)\n"
|
|
"<dev_type> device type (b=block, c=character)\n"
|
|
"<maj> major number of nod\n"
|
|
"<min> minor number of nod\n"
|
|
"<hard links> space separated list of other links to file\n"
|
|
"\n"
|
|
"example:\n"
|
|
"# A simple initramfs\n"
|
|
"dir /dev 0755 0 0\n"
|
|
"nod /dev/console 0600 0 0 c 5 1\n"
|
|
"dir /root 0700 0 0\n"
|
|
"dir /sbin 0755 0 0\n"
|
|
"file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n"
|
|
"\n"
|
|
"<timestamp> is time in seconds since Epoch that will be used\n"
|
|
"as mtime for symlinks, special files and directories. The default\n"
|
|
"is to use the current time for these entries.\n",
|
|
prog);
|
|
}
|
|
|
|
static const struct file_handler file_handler_table[] = {
|
|
{
|
|
.type = "file",
|
|
.handler = cpio_mkfile_line,
|
|
}, {
|
|
.type = "nod",
|
|
.handler = cpio_mknod_line,
|
|
}, {
|
|
.type = "dir",
|
|
.handler = cpio_mkdir_line,
|
|
}, {
|
|
.type = "slink",
|
|
.handler = cpio_mkslink_line,
|
|
}, {
|
|
.type = "pipe",
|
|
.handler = cpio_mkpipe_line,
|
|
}, {
|
|
.type = "sock",
|
|
.handler = cpio_mksock_line,
|
|
}, {
|
|
.type = NULL,
|
|
.handler = NULL,
|
|
}
|
|
};
|
|
|
|
#define LINE_SIZE (2 * PATH_MAX + 50)
|
|
|
|
int main (int argc, char *argv[])
|
|
{
|
|
FILE *cpio_list;
|
|
char line[LINE_SIZE];
|
|
char *args, *type;
|
|
int ec = 0;
|
|
int line_nr = 0;
|
|
const char *filename;
|
|
|
|
default_mtime = time(NULL);
|
|
while (1) {
|
|
int opt = getopt(argc, argv, "t:h");
|
|
char *invalid;
|
|
|
|
if (opt == -1)
|
|
break;
|
|
switch (opt) {
|
|
case 't':
|
|
default_mtime = strtol(optarg, &invalid, 10);
|
|
if (!*optarg || *invalid) {
|
|
fprintf(stderr, "Invalid timestamp: %s\n",
|
|
optarg);
|
|
usage(argv[0]);
|
|
exit(1);
|
|
}
|
|
break;
|
|
case 'h':
|
|
case '?':
|
|
usage(argv[0]);
|
|
exit(opt == 'h' ? 0 : 1);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Timestamps after 2106-02-07 06:28:15 UTC have an ascii hex time_t
|
|
* representation that exceeds 8 chars and breaks the cpio header
|
|
* specification.
|
|
*/
|
|
if (default_mtime > 0xffffffff) {
|
|
fprintf(stderr, "ERROR: Timestamp too large for cpio format\n");
|
|
exit(1);
|
|
}
|
|
|
|
if (argc - optind != 1) {
|
|
usage(argv[0]);
|
|
exit(1);
|
|
}
|
|
filename = argv[optind];
|
|
if (!strcmp(filename, "-"))
|
|
cpio_list = stdin;
|
|
else if (!(cpio_list = fopen(filename, "r"))) {
|
|
fprintf(stderr, "ERROR: unable to open '%s': %s\n\n",
|
|
filename, strerror(errno));
|
|
usage(argv[0]);
|
|
exit(1);
|
|
}
|
|
|
|
while (fgets(line, LINE_SIZE, cpio_list)) {
|
|
int type_idx;
|
|
size_t slen = strlen(line);
|
|
|
|
line_nr++;
|
|
|
|
if ('#' == *line) {
|
|
/* comment - skip to next line */
|
|
continue;
|
|
}
|
|
|
|
if (! (type = strtok(line, " \t"))) {
|
|
fprintf(stderr,
|
|
"ERROR: incorrect format, could not locate file type line %d: '%s'\n",
|
|
line_nr, line);
|
|
ec = -1;
|
|
break;
|
|
}
|
|
|
|
if ('\n' == *type) {
|
|
/* a blank line */
|
|
continue;
|
|
}
|
|
|
|
if (slen == strlen(type)) {
|
|
/* must be an empty line */
|
|
continue;
|
|
}
|
|
|
|
if (! (args = strtok(NULL, "\n"))) {
|
|
fprintf(stderr,
|
|
"ERROR: incorrect format, newline required line %d: '%s'\n",
|
|
line_nr, line);
|
|
ec = -1;
|
|
}
|
|
|
|
for (type_idx = 0; file_handler_table[type_idx].type; type_idx++) {
|
|
int rc;
|
|
if (! strcmp(line, file_handler_table[type_idx].type)) {
|
|
if ((rc = file_handler_table[type_idx].handler(args))) {
|
|
ec = rc;
|
|
fprintf(stderr, " line %d\n", line_nr);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (NULL == file_handler_table[type_idx].type) {
|
|
fprintf(stderr, "unknown file type line %d: '%s'\n",
|
|
line_nr, line);
|
|
}
|
|
}
|
|
if (ec == 0)
|
|
cpio_trailer();
|
|
|
|
exit(ec);
|
|
}
|