From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cantor2.suse.de ([195.135.220.15]:57177 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753893AbaETQd4 (ORCPT ); Tue, 20 May 2014 12:33:56 -0400 Date: Tue, 20 May 2014 18:33:52 +0200 From: David Sterba To: Anand Jain Cc: linux-btrfs@vger.kernel.org, sandeen@redhat.com, rm@romanrm.net Subject: Re: [PATCH 1/2 v2] btrfs: label should not contain return char Message-ID: <20140520163352.GL31608@twin.jikos.cz> Reply-To: dsterba@suse.cz References: <1400519071-5580-1-git-send-email-anand.jain@oracle.com> <1400567808-9494-1-git-send-email-anand.jain@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1400567808-9494-1-git-send-email-anand.jain@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Tue, May 20, 2014 at 02:36:48PM +0800, Anand Jain wrote: > From: Anand Jain > > generally if you use > echo "test" > /sys/fs/btrfs//label > it would introduce return char at the end and it can not > be part of the label. The correct command is > echo -n "test" > /sys/fs/btrfs//label > > This patch will check for this user error > > Signed-off-by: Anand Jain > --- > v2: accepts review comments. Thanks Eric and Roman > > fs/btrfs/sysfs.c | 20 +++++++++++++++++--- > 1 files changed, 17 insertions(+), 3 deletions(-) > > diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c > index c5eb214..ca63fcd 100644 > --- a/fs/btrfs/sysfs.c > +++ b/fs/btrfs/sysfs.c > @@ -373,22 +373,36 @@ static ssize_t btrfs_label_store(struct kobject *kobj, > struct btrfs_trans_handle *trans; > struct btrfs_root *root = fs_info->fs_root; > int ret; > + char *label; > + char *pos; > > - if (len >= BTRFS_LABEL_SIZE) { > + label = kzalloc(len, GFP_NOFS); You can avoid allocating the buffer entirely: - search for '\n', if found, use only that amount of bytes - check for maximum size, copy to label if ok