From: Hubert Kario <kario@wit.edu.pl>
Date: Sun, 19 Feb 2012 20:11:46 +0000 (+0100)
Subject: Fix segmentation fault when opening invalid file system
X-Git-Tag: upstream/0.20.rc1~26
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ff2b80b460bbb5ff85f543661be218ffab0e286b;p=platform%2Fupstream%2Fbtrfs-progs.git

Fix segmentation fault when opening invalid file system

Signed-off-by: Hubert Kario <kario@wit.edu.pl>
---

diff --git a/btrfslabel.c b/btrfslabel.c
index da694e1..bf73802 100644
--- a/btrfslabel.c
+++ b/btrfslabel.c
@@ -55,6 +55,8 @@ static void change_label_unmounted(char *dev, char *nLabel)
         * 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);