From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933213AbdABP6I (ORCPT ); Mon, 2 Jan 2017 10:58:08 -0500 Received: from mx2.suse.de ([195.135.220.15]:52565 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756029AbdABP6G (ORCPT ); Mon, 2 Jan 2017 10:58:06 -0500 Date: Mon, 2 Jan 2017 16:58:03 +0100 From: Jan Kara To: Chandan Rajendra Cc: axboe@kernel.dk, jack@suse.cz, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] clean_bdev_aliases: Prevent cleaning blocks that are not in block range Message-ID: <20170102155803.GH18058@quack2.suse.cz> References: <1482672663-17122-1-git-send-email-chandan@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1482672663-17122-1-git-send-email-chandan@linux.vnet.ibm.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun 25-12-16 19:01:03, Chandan Rajendra wrote: > The first block to be cleaned may start at a non-zero page offset. In > such a scenario clean_bdev_aliases() will end up cleaning blocks that > do not fall in the range of blocks to be cleaned. This commit fixes the > issue by skipping blocks that do not fall in valid block range. > > Signed-off-by: Chandan Rajendra Ah, very good catch! How did you spot this? The patch looks good. You can add: Reviewed-by: Jan Kara Jens, please merge this fix quickly as we may end up discarding changes to innocent metadata blocks due to this... Thanks! Honza > --- > fs/buffer.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/buffer.c b/fs/buffer.c > index 1df2bd5..28484b3 100644 > --- a/fs/buffer.c > +++ b/fs/buffer.c > @@ -1660,7 +1660,7 @@ void clean_bdev_aliases(struct block_device *bdev, sector_t block, sector_t len) > head = page_buffers(page); > bh = head; > do { > - if (!buffer_mapped(bh)) > + if (!buffer_mapped(bh) || (bh->b_blocknr < block)) > goto next; > if (bh->b_blocknr >= block + len) > break; > -- > 2.5.5 > -- Jan Kara SUSE Labs, CR