mirror of
https://github.com/dracutdevs/dracut.git
synced 2024-10-27 00:55:34 +03:00
use switch_root code from http://pjones.fedorapeople.org/mkstart/usr/lib/mkstart/switchroot.c
This commit is contained in:
Harald Hoyer
parent
883594c833
commit
63efe29bb3
@ -96,7 +96,7 @@ source_all pre-pivot
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getarg break && emergency_shell
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kill $(pidof udevd)
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echo "Switching to real root filesystem $root"
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exec switch_root "$NEWROOT" "$INIT" $CMDLINE || {
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exec switch_root -n "$NEWROOT" || {
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# davej doesn't like initrd bugs
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echo "Something went very badly wrong in the initrd. Please "
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echo "file a bug against mkinitrd."
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726
switch_root.c
726
switch_root.c
@ -1,10 +1,7 @@
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/*
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* switch_root.c
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* switchroot.c - switch to new root directory and start init.
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*
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* Code to switch from initramfs to system root.
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* Based on nash.c from mkinitrd
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*
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* Copyright 2002-2009 Red Hat, Inc. All rights reserved.
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* Copyright 2002-2008 Red Hat, Inc. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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@ -19,538 +16,311 @@
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*
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* Author(s): Erik Troan <ewt@redhat.com>
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* Jeremy Katz <katzj@redhat.com>
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* Peter Jones <pjones@redhat.com>
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* Harald Hoyer <harald@redhat.com>
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* Authors:
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* Peter Jones <pjones@redhat.com>
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* Jeremy Katz <katzj@redhat.com>
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*/
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#define _GNU_SOURCE 1
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#include <sys/mount.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include <stdio.h>
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#include <dirent.h>
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#include <alloca.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <string.h>
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#include <errno.h>
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#include <mntent.h>
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#include <stdlib.h>
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#include <ctype.h>
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#include <sys/mount.h>
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#include <fcntl.h>
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#include <linux/fs.h>
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#ifndef MNT_FORCE
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#define MNT_FORCE 0x1
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#ifndef MS_MOVE
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#define MS_MOVE 8192
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#endif
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#ifndef MNT_DETACH
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#define MNT_DETACH 0x2
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#endif
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enum {
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ok,
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err_no_directory,
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err_usage,
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};
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#define asprintfa(str, fmt, ...) ({ \
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char *_tmp = NULL; \
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int _rc; \
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_rc = asprintf((str), (fmt), __VA_ARGS__); \
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if (_rc != -1) { \
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_tmp = strdupa(*(str)); \
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if (!_tmp) { \
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_rc = -1; \
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} else { \
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free(*(str)); \
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*(str) = _tmp; \
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} \
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} \
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_rc; \
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})
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static inline int
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setFdCoe(int fd, int enable)
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static int readFD(int fd, char **buf)
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{
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int rc;
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long flags = 0;
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char *p;
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size_t size = 16384;
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int s = 0, filesize = 0;
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rc = fcntl(fd, F_GETFD, &flags);
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if (rc < 0)
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return rc;
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if (!(*buf = calloc (16384, sizeof (char))))
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return -1;
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if (enable)
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flags |= FD_CLOEXEC;
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else
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flags &= ~FD_CLOEXEC;
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do {
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p = *buf + filesize;
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s = read(fd, p, 16384 - s);
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if (s < 0)
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break;
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filesize += s;
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/* only exit for empty reads */
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if (s == 0)
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break;
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else if (s == 16384) {
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*buf = realloc(*buf, size + 16384);
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memset(*buf + size, '\0', 16384);
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size += s;
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s = 0;
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} else {
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size += s;
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}
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} while (1);
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rc = fcntl(fd, F_SETFD, flags);
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return rc;
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*buf = realloc(*buf, filesize+1);
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(*buf)[filesize] = '\0';
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return *buf ? filesize : -1;
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}
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static char *
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getArg(char * cmd, char * end, char ** arg)
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static char *getKernelCmdLine(void)
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{
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char quote = '\0';
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static char *cmdline = NULL;
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int fd = -1;
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int errnum;
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if (!cmd || cmd >= end)
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return NULL;
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fd = open("/proc/cmdline", O_RDONLY);
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if (fd < 0) {
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errnum = errno;
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fprintf(stderr, "Error: Could not open /proc/cmdline: %m\n");
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errno = errnum;
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return NULL;
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}
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if (readFD(fd, &cmdline) < 0) {
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errnum = errno;
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fprintf(stderr, "Error: could not read /proc/cmdline: %m\n");
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close(fd);
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errno = errnum;
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return NULL;
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}
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close(fd);
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while (isspace(*cmd) && cmd < end)
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cmd++;
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if (cmd >= end)
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return NULL;
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if (*cmd == '"')
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cmd++, quote = '"';
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else if (*cmd == '\'')
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cmd++, quote = '\'';
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if (quote) {
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*arg = cmd;
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/* This doesn't support \ escapes */
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while (cmd < end && *cmd != quote)
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cmd++;
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if (cmd == end) {
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printf("error: quote mismatch for %s\n", *arg);
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return NULL;
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}
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*cmd = '\0';
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cmd++;
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} else {
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*arg = cmd;
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while (!isspace(*cmd) && cmd < end)
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cmd++;
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*cmd = '\0';
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if (**arg == '$')
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*arg = getenv(*arg+1);
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if (*arg == NULL)
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*arg = "";
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}
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cmd++;
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while (isspace(*cmd))
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cmd++;
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return cmd;
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return cmdline;
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}
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static int
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mountCommand(char * cmd, char * end)
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/* get the start of a kernel arg "arg". returns everything after it
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* (useful for things like getting the args to init=). so if you only
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* want one arg, you need to terminate it at the n */
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static char *getKernelArg(char *arg)
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{
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char * fsType = NULL;
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char * device, *spec;
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char * mntPoint;
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char * opts = NULL;
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int rc = 0;
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int flags = MS_MGC_VAL;
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char * newOpts;
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char *start;
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char *cmdline;
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int len;
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if (!(cmd = getArg(cmd, end, &spec))) {
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printf(
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"usage: mount [--ro] [-o <opts>] -t <type> <device> <mntpoint>\n");
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return 1;
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}
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cmdline = start = getKernelCmdLine();
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if (start == NULL)
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return NULL;
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while (cmd && *spec == '-') {
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if (!strcmp(spec, "--ro")) {
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flags |= MS_RDONLY;
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} else if (!strcmp(spec, "--bind")) {
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flags = MS_BIND;
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fsType = "none";
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} else if (!strcmp(spec, "--move")) {
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flags = MS_MOVE;
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fsType = "none";
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} else if (!strcmp(spec, "-o")) {
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cmd = getArg(cmd, end, &opts);
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if (!cmd) {
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printf("mount: -o requires arguments\n");
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return 1;
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}
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} else if (!strcmp(spec, "-t")) {
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if (!(cmd = getArg(cmd, end, &fsType))) {
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printf("mount: missing filesystem type\n");
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return 1;
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}
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}
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while (*start) {
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if (isspace(*start)) {
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start++;
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continue;
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}
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cmd = getArg(cmd, end, &spec);
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}
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len = strlen(arg);
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/* don't return if it's a different argument that merely starts
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* like this one. */
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if (strncmp(start, arg, len) == 0) {
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if (start[len] == '=')
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return start + len + 1;
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if (!start[len] || isspace(start[len]))
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return start + len;
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}
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while (*++start && !isspace(*start))
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;
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}
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if (!cmd) {
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printf("mount: missing device or mountpoint\n");
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return 1;
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}
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if (!(cmd = getArg(cmd, end, &mntPoint))) {
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struct mntent *mnt;
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FILE *fstab;
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fstab = fopen("/etc/fstab", "r");
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if (!fstab) {
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printf("mount: missing mount point\n");
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return 1;
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}
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do {
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if (!(mnt = getmntent(fstab))) {
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printf("mount: missing mount point\n");
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fclose(fstab);
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return 1;
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}
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if (!strcmp(mnt->mnt_dir, spec)) {
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spec = mnt->mnt_fsname;
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mntPoint = mnt->mnt_dir;
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if (!strcmp(mnt->mnt_type, "bind")) {
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flags |= MS_BIND;
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fsType = "none";
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} else
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fsType = mnt->mnt_type;
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opts = mnt->mnt_opts;
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break;
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}
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} while(1);
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fclose(fstab);
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}
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if (!fsType) {
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printf("mount: filesystem type expected\n");
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return 1;
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}
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if (cmd && cmd < end) {
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printf("mount: unexpected arguments\n");
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return 1;
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}
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/* need to deal with options */
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if (opts) {
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char * end;
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char * start = opts;
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newOpts = alloca(strlen(opts) + 1);
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*newOpts = '\0';
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while (*start) {
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end = strchr(start, ',');
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if (!end) {
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end = start + strlen(start);
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} else {
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*end = '\0';
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end++;
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}
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if (!strcmp(start, "ro"))
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flags |= MS_RDONLY;
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else if (!strcmp(start, "rw"))
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flags &= ~MS_RDONLY;
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else if (!strcmp(start, "nosuid"))
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flags |= MS_NOSUID;
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else if (!strcmp(start, "suid"))
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flags &= ~MS_NOSUID;
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else if (!strcmp(start, "nodev"))
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flags |= MS_NODEV;
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else if (!strcmp(start, "dev"))
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flags &= ~MS_NODEV;
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else if (!strcmp(start, "noexec"))
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flags |= MS_NOEXEC;
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else if (!strcmp(start, "exec"))
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flags &= ~MS_NOEXEC;
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else if (!strcmp(start, "sync"))
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flags |= MS_SYNCHRONOUS;
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else if (!strcmp(start, "async"))
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flags &= ~MS_SYNCHRONOUS;
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else if (!strcmp(start, "nodiratime"))
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flags |= MS_NODIRATIME;
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else if (!strcmp(start, "diratime"))
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flags &= ~MS_NODIRATIME;
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||||
else if (!strcmp(start, "noatime"))
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flags |= MS_NOATIME;
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else if (!strcmp(start, "atime"))
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||||
flags &= ~MS_NOATIME;
|
||||
else if (!strcmp(start, "relatime"))
|
||||
flags |= MS_RELATIME;
|
||||
else if (!strcmp(start, "norelatime"))
|
||||
flags &= ~MS_RELATIME;
|
||||
else if (!strcmp(start, "remount"))
|
||||
flags |= MS_REMOUNT;
|
||||
else if (!strcmp(start, "bind"))
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||||
flags |= MS_BIND;
|
||||
else if (!strcmp(start, "defaults"))
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||||
;
|
||||
else {
|
||||
if (*newOpts)
|
||||
strcat(newOpts, ",");
|
||||
strcat(newOpts, start);
|
||||
}
|
||||
|
||||
start = end;
|
||||
}
|
||||
|
||||
opts = newOpts;
|
||||
}
|
||||
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device = strdupa(spec);
|
||||
|
||||
if (!device) {
|
||||
printf("mount: could not find filesystem '%s'\n", spec);
|
||||
return 1;
|
||||
}
|
||||
|
||||
{
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||||
char *mount_opts = NULL;
|
||||
mount_opts = opts;
|
||||
if (mount(device, mntPoint, fsType, flags, mount_opts) < 0) {
|
||||
printf("mount: error mounting %s on %s as %s: %m\n",
|
||||
device, mntPoint, fsType);
|
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rc = 1;
|
||||
}
|
||||
}
|
||||
|
||||
return rc;
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* remove all files/directories below dirName -- don't cross mountpoints */
|
||||
static int
|
||||
recursiveRemove(char * dirName)
|
||||
#define MAX_INIT_ARGS 32
|
||||
static int build_init_args(char **init, char ***initargs_out)
|
||||
{
|
||||
struct stat sb,rb;
|
||||
DIR * dir;
|
||||
struct dirent * d;
|
||||
char * strBuf = alloca(strlen(dirName) + 1024);
|
||||
const char *initprogs[] = { "/sbin/init", "/etc/init",
|
||||
"/bin/init", "/bin/sh", NULL };
|
||||
const char *ignoreargs[] = { "console=", "BOOT_IMAGE=", NULL };
|
||||
char *cmdline = NULL;
|
||||
char **initargs;
|
||||
|
||||
if (!(dir = opendir(dirName))) {
|
||||
printf("error opening %s: %m\n", dirName);
|
||||
return 0;
|
||||
}
|
||||
int i = 0;
|
||||
|
||||
if (fstat(dirfd(dir),&rb)) {
|
||||
printf("unable to stat %s: %m\n", dirName);
|
||||
closedir(dir);
|
||||
return 0;
|
||||
}
|
||||
*init = getKernelArg("init");
|
||||
|
||||
errno = 0;
|
||||
while ((d = readdir(dir))) {
|
||||
errno = 0;
|
||||
if (*init == NULL) {
|
||||
int j;
|
||||
cmdline = getKernelCmdLine();
|
||||
if (cmdline == NULL)
|
||||
return -1;
|
||||
|
||||
if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, "..")) {
|
||||
errno = 0;
|
||||
continue;
|
||||
}
|
||||
for (j = 0; initprogs[j] != NULL; j++) {
|
||||
if (!access(initprogs[j], X_OK)) {
|
||||
*init = strdup(initprogs[j]);
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
strcpy(strBuf, dirName);
|
||||
strcat(strBuf, "/");
|
||||
strcat(strBuf, d->d_name);
|
||||
initargs = (char **)calloc(MAX_INIT_ARGS+1, sizeof (char *));
|
||||
if (initargs == NULL)
|
||||
return -1;
|
||||
|
||||
if (lstat(strBuf, &sb)) {
|
||||
printf("failed to stat %s: %m\n", strBuf);
|
||||
errno = 0;
|
||||
continue;
|
||||
}
|
||||
if (cmdline && *init) {
|
||||
initargs[i++] = *init;
|
||||
} else {
|
||||
cmdline = *init;
|
||||
initargs[0] = NULL;
|
||||
}
|
||||
|
||||
/* only descend into subdirectories if device is same as dir */
|
||||
if (S_ISDIR(sb.st_mode)) {
|
||||
if (sb.st_dev == rb.st_dev) {
|
||||
recursiveRemove(strBuf);
|
||||
if (rmdir(strBuf))
|
||||
printf("failed to rmdir %s: %m\n", strBuf);
|
||||
}
|
||||
errno = 0;
|
||||
continue;
|
||||
}
|
||||
if (cmdline) {
|
||||
char quote = '\0';
|
||||
char *chptr;
|
||||
char *start;
|
||||
|
||||
if (unlink(strBuf)) {
|
||||
printf("failed to remove %s: %m\n", strBuf);
|
||||
errno = 0;
|
||||
continue;
|
||||
}
|
||||
}
|
||||
start = chptr = cmdline;
|
||||
for (; (i < MAX_INIT_ARGS) && (*start != '\0'); i++) {
|
||||
while (*chptr && (*chptr != quote)) {
|
||||
if (isspace(*chptr) && quote == '\0')
|
||||
break;
|
||||
if (*chptr == '"' || *chptr == '\'')
|
||||
quote = *chptr;
|
||||
chptr++;
|
||||
}
|
||||
|
||||
if (errno) {
|
||||
closedir(dir);
|
||||
printf("error reading from %s: %m\n", dirName);
|
||||
return 1;
|
||||
}
|
||||
if (quote == '"' || quote == '\'')
|
||||
chptr++;
|
||||
if (*chptr != '\0')
|
||||
*(chptr++) = '\0';
|
||||
|
||||
closedir(dir);
|
||||
/* There are some magic parameters added *after*
|
||||
* everything you pass, including a console= from the
|
||||
* x86_64 kernel and BOOT_IMAGE= by syslinux. Bash
|
||||
* doesn't know what they mean, so it then exits, init
|
||||
* gets killed, desaster ensues. *sigh*.
|
||||
*/
|
||||
int j;
|
||||
for (j = 0; ignoreargs[j] != NULL; j++) {
|
||||
if (cmdline == *init && !strncmp(start, ignoreargs[j], strlen(ignoreargs[j]))) {
|
||||
if (!*chptr)
|
||||
initargs[i] = NULL;
|
||||
else
|
||||
i--;
|
||||
start = chptr;
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (start == chptr)
|
||||
continue;
|
||||
|
||||
return 0;
|
||||
if (start[0] == '\0')
|
||||
i--;
|
||||
else
|
||||
initargs[i] = strdup(start);
|
||||
start = chptr;
|
||||
}
|
||||
}
|
||||
|
||||
if (initargs[i-1] != NULL)
|
||||
initargs[i] = NULL;
|
||||
|
||||
*initargs_out = initargs;
|
||||
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void
|
||||
mountMntEnt(const struct mntent *mnt)
|
||||
static void switchroot(const char *newroot)
|
||||
{
|
||||
char *start = NULL, *end;
|
||||
char *target = NULL;
|
||||
struct stat sb;
|
||||
|
||||
printf("mounting %s\n", mnt->mnt_dir);
|
||||
if (asprintfa(&target, ".%s", mnt->mnt_dir) < 0) {
|
||||
printf("setuproot: out of memory while mounting %s\n",
|
||||
mnt->mnt_dir);
|
||||
return;
|
||||
}
|
||||
|
||||
if (stat(target, &sb) < 0)
|
||||
return;
|
||||
|
||||
if (asprintf(&start, "-o %s -t %s %s .%s\n",
|
||||
mnt->mnt_opts, mnt->mnt_type, mnt->mnt_fsname,
|
||||
mnt->mnt_dir) < 0) {
|
||||
printf("setuproot: out of memory while mounting %s\n",
|
||||
mnt->mnt_dir);
|
||||
return;
|
||||
}
|
||||
|
||||
end = start + 1;
|
||||
while (*end && (*end != '\n'))
|
||||
end++;
|
||||
/* end points to the \n at the end of the command */
|
||||
|
||||
if (mountCommand(start, end) != 0)
|
||||
printf("setuproot: mount returned error\n");
|
||||
/* Don't try to unmount the old "/", there's no way to do it. */
|
||||
const char *umounts[] = { "/dev", "/proc", "/sys", NULL };
|
||||
char *init, **initargs;
|
||||
int errnum;
|
||||
int rc;
|
||||
int i;
|
||||
|
||||
rc = build_init_args(&init, &initargs);
|
||||
if (rc < 0)
|
||||
return;
|
||||
|
||||
for (i = 0; umounts[i] != NULL; i++) {
|
||||
if (umount2(umounts[i], MNT_DETACH) < 0) {
|
||||
fprintf(stderr, "Error unmounting old %s: %m\n",
|
||||
umounts[i]);
|
||||
fprintf(stderr, "Forcing unmount of %s\n", umounts[i]);
|
||||
umount2(umounts[i], MNT_FORCE);
|
||||
}
|
||||
}
|
||||
|
||||
chdir(newroot);
|
||||
|
||||
if (mount(newroot, "/", NULL, MS_MOVE, NULL) < 0) {
|
||||
errnum = errno;
|
||||
fprintf(stderr, "switchroot: mount failed: %m\n");
|
||||
errno = errnum;
|
||||
return;
|
||||
}
|
||||
|
||||
if (chroot(".")) {
|
||||
errnum = errno;
|
||||
fprintf(stderr, "switchroot: chroot failed: %m\n");
|
||||
errno = errnum;
|
||||
return;
|
||||
}
|
||||
|
||||
if (access(initargs[0], X_OK))
|
||||
fprintf(stderr, "WARNING: can't access %s\n", initargs[0]);
|
||||
|
||||
execv(initargs[0], initargs);
|
||||
return;
|
||||
}
|
||||
|
||||
static int
|
||||
setuprootCommand(char *new)
|
||||
static void usage(FILE *output)
|
||||
{
|
||||
FILE *fp;
|
||||
|
||||
printf("Setting up new root fs\n");
|
||||
|
||||
if (chdir(new)) {
|
||||
printf("setuproot: chdir(%s) failed: %m\n", new);
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (mount("/dev", "./dev", NULL, MS_BIND, NULL) < 0)
|
||||
printf("setuproot: moving /dev failed: %m\n");
|
||||
|
||||
fp = setmntent("./etc/fstab.sys", "r");
|
||||
if (fp)
|
||||
printf("using fstab.sys from mounted FS\n");
|
||||
else {
|
||||
fp = setmntent("/etc/fstab.sys", "r");
|
||||
if (fp)
|
||||
printf("using fstab.sys from initrd\n");
|
||||
}
|
||||
if (fp) {
|
||||
struct mntent *mnt;
|
||||
|
||||
while((mnt = getmntent(fp)))
|
||||
mountMntEnt(mnt);
|
||||
endmntent(fp);
|
||||
} else {
|
||||
struct {
|
||||
char *source;
|
||||
char *target;
|
||||
char *type;
|
||||
int flags;
|
||||
void *data;
|
||||
int raise;
|
||||
} fstab[] = {
|
||||
{ "/proc", "./proc", "proc", 0, NULL },
|
||||
{ "/sys", "./sys", "sysfs", 0, NULL },
|
||||
#if 0
|
||||
{ "/dev/pts", "./dev/pts", "devpts", 0, "gid=5,mode=620" },
|
||||
{ "/dev/shm", "./dev/shm", "tmpfs", 0, NULL },
|
||||
{ "/selinux", "/selinux", "selinuxfs", 0, NULL },
|
||||
#endif
|
||||
{ NULL, }
|
||||
};
|
||||
int i = 0;
|
||||
|
||||
printf("no fstab.sys, mounting internal defaults\n");
|
||||
for (; fstab[i].source != NULL; i++) {
|
||||
if (mount(fstab[i].source, fstab[i].target, fstab[i].type,
|
||||
fstab[i].flags, fstab[i].data) < 0)
|
||||
printf("setuproot: error mounting %s: %m\n",
|
||||
fstab[i].source);
|
||||
}
|
||||
}
|
||||
|
||||
chdir("/");
|
||||
return 0;
|
||||
fprintf(output, "usage: switchroot {-n|--newroot} <newrootdir>\n");
|
||||
if (output == stderr)
|
||||
exit(err_usage);
|
||||
exit(ok);
|
||||
}
|
||||
|
||||
int main(int argc, char **argv)
|
||||
int main(int argc, char *argv[])
|
||||
{
|
||||
/* Don't try to unmount the old "/", there's no way to do it. */
|
||||
const char *umounts[] = { "/dev", "/proc", "/sys", NULL };
|
||||
char *new = NULL;
|
||||
int fd, i = 0;
|
||||
int i;
|
||||
char *newroot = NULL;
|
||||
|
||||
argv++;
|
||||
new = argv[0];
|
||||
argv++;
|
||||
printf("Switching to root: %s\n", new);
|
||||
for (i = 1; i < argc; i++) {
|
||||
if (!strcmp(argv[i], "--help")
|
||||
|| !strcmp(argv[i], "-h")
|
||||
|| !strcmp(argv[i], "--usage")) {
|
||||
usage(stdout);
|
||||
} else if (!strcmp(argv[i], "-n")
|
||||
|| !strcmp(argv[i], "--newroot")) {
|
||||
newroot = argv[++i];
|
||||
} else if (!strncmp(argv[i], "--newroot=", 10)) {
|
||||
newroot = argv[i] + 10;
|
||||
} else {
|
||||
usage(stderr);
|
||||
}
|
||||
}
|
||||
|
||||
setuprootCommand(new);
|
||||
if (newroot == NULL || newroot[0] == '\0') {
|
||||
usage(stderr);
|
||||
}
|
||||
|
||||
fd = open("/", O_RDONLY);
|
||||
for (; umounts[i] != NULL; i++) {
|
||||
printf("unmounting old %s\n", umounts[i]);
|
||||
if (umount2(umounts[i], MNT_DETACH) < 0) {
|
||||
printf("ERROR unmounting old %s: %m\n",umounts[i]);
|
||||
printf("forcing unmount of %s\n", umounts[i]);
|
||||
umount2(umounts[i], MNT_FORCE);
|
||||
}
|
||||
}
|
||||
i=0;
|
||||
switchroot(newroot);
|
||||
|
||||
chdir(new);
|
||||
|
||||
recursiveRemove("/");
|
||||
|
||||
if (mount(new, "/", NULL, MS_MOVE, NULL) < 0) {
|
||||
printf("switchroot: mount failed: %m\n");
|
||||
close(fd);
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (chroot(".")) {
|
||||
printf("switchroot: chroot() failed: %m\n");
|
||||
close(fd);
|
||||
return 1;
|
||||
}
|
||||
|
||||
/* release the old "/" */
|
||||
close(fd);
|
||||
|
||||
close(3);
|
||||
if ((fd = open("/dev/console", O_RDWR)) < 0) {
|
||||
printf("ERROR opening /dev/console: %m\n");
|
||||
printf("Trying to use fd 0 instead.\n");
|
||||
fd = dup2(0, 3);
|
||||
} else {
|
||||
setFdCoe(fd, 0);
|
||||
if (fd != 3) {
|
||||
dup2(fd, 3);
|
||||
close(fd);
|
||||
fd = 3;
|
||||
}
|
||||
}
|
||||
close(0);
|
||||
dup2(fd, 0);
|
||||
close(1);
|
||||
dup2(fd, 1);
|
||||
close(2);
|
||||
dup2(fd, 2);
|
||||
close(fd);
|
||||
|
||||
if (access(argv[0], X_OK)) {
|
||||
printf("WARNING: can't access %s\n", argv[0]);
|
||||
}
|
||||
|
||||
execv(argv[0], argv);
|
||||
|
||||
printf("exec of init (%s) failed!!!: %m\n", argv[0]);
|
||||
return 1;
|
||||
fprintf(stderr, "switchroot has failed. Sorry.\n");
|
||||
return 1;
|
||||
}
|
||||
|
||||
/*
|
||||
* vim:noet:ts=8:sw=8:sts=8
|
||||
*/
|
||||
|
||||
Loading…
Reference in New Issue
Block a user