commit 66ac9fe7bacf9fa76c472efc7a7aaa590c7bce6a upstream. Add a sanity check for the fs_info as we will dereference it, similar to what the 'store features' handler does. Signed-off-by: David Sterba <dsterba@xxxxxxxx> --- fs/btrfs/sysfs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c index 6a6bb600b1ff..3d14618ce54b 100644 --- a/fs/btrfs/sysfs.c +++ b/fs/btrfs/sysfs.c @@ -377,6 +377,9 @@ static ssize_t btrfs_label_store(struct kobject *kobj, struct btrfs_fs_info *fs_info = to_fs_info(kobj); size_t p_len; + if (!fs_info) + return -EPERM; + if (fs_info->sb->s_flags & MS_RDONLY) return -EROFS; -- 2.7.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html