btrfs-progs/btrfslabel.c
Anand Jain f4dfc8f6ed Btrfs-progs: seg fault in get_label_unmounted
btrfs f l /
No valid Btrfs found on /
Segmentation fault (core dumped)

open_ctree can return NULL, we need to check that.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
2012-10-04 16:26:32 -04:00

129 lines
3.1 KiB
C

/*
* Copyright (C) 2008 Morey Roof. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#define _GNU_SOURCE
#ifndef __CHECKER__
#include <sys/ioctl.h>
#include <sys/mount.h>
#include "ioctl.h"
#endif /* __CHECKER__ */
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/fs.h>
#include <linux/limits.h>
#include <ctype.h>
#include "kerncompat.h"
#include "ctree.h"
#include "utils.h"
#include "version.h"
#include "disk-io.h"
#include "transaction.h"
#define MOUNTED 1
#define UNMOUNTED 2
#define GET_LABEL 3
#define SET_LABEL 4
static void change_label_unmounted(char *dev, char *nLabel)
{
struct btrfs_root *root;
struct btrfs_trans_handle *trans;
/* Open the super_block at the default location
* and as read-write.
*/
root = open_ctree(dev, 0, 1);
if (!root) /* errors are printed by open_ctree() */
return;
trans = btrfs_start_transaction(root, 1);
strncpy(root->fs_info->super_copy.label, nLabel, BTRFS_LABEL_SIZE);
root->fs_info->super_copy.label[BTRFS_LABEL_SIZE-1] = 0;
btrfs_commit_transaction(trans, root);
/* Now we close it since we are done. */
close_ctree(root);
}
int get_label_unmounted(char *dev)
{
struct btrfs_root *root;
/* Open the super_block at the default location
* and as read-only.
*/
root = open_ctree(dev, 0, 0);
if(!root)
return -1;
fprintf(stdout, "%s\n", root->fs_info->super_copy.label);
/* Now we close it since we are done. */
close_ctree(root);
return 0;
}
int get_label(char *btrfs_dev)
{
int ret;
ret = check_mounted(btrfs_dev);
if (ret < 0)
{
fprintf(stderr, "FATAL: error checking %s mount status\n", btrfs_dev);
return -1;
}
if(ret != 0)
{
fprintf(stderr, "FATAL: the filesystem has to be unmounted\n");
return -2;
}
ret = get_label_unmounted(btrfs_dev);
return ret;
}
int set_label(char *btrfs_dev, char *nLabel)
{
int ret;
ret = check_mounted(btrfs_dev);
if (ret < 0)
{
fprintf(stderr, "FATAL: error checking %s mount status\n", btrfs_dev);
return -1;
}
if(ret != 0)
{
fprintf(stderr, "FATAL: the filesystem has to be unmounted\n");
return -2;
}
change_label_unmounted(btrfs_dev, nLabel);
return 0;
}