From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Subject: [patch] dm raid: pointer math issue in super_sync() Date: Tue, 21 Oct 2014 15:43:36 +0300 Message-ID: <20141021124336.GA20791@mwanda> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline Sender: kernel-janitors-owner@vger.kernel.org To: Alasdair Kergon Cc: Mike Snitzer , dm-devel@redhat.com, Neil Brown , linux-raid@vger.kernel.org, kernel-janitors@vger.kernel.org List-Id: linux-raid.ids "sb" is a dm_raid_superblock struct pointer so the pointer math doesn't work and we will end up corrupting memory. Signed-off-by: Dan Carpenter diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index b802644..a7cb9dd 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -826,7 +826,7 @@ static void super_sync(struct mddev *mddev, struct md_rdev *rdev) test_bit(Faulty, &(rs->dev[i].rdev.flags))) failed_devices |= (1ULL << i); - memset(sb + sizeof(*sb), 0, rdev->sb_size - sizeof(*sb)); + memset(sb + 1, 0, rdev->sb_size - sizeof(*sb)); sb->magic = cpu_to_le32(DM_RAID_MAGIC); sb->features = cpu_to_le32(0); /* No features yet */