Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753516AbbHNHEf (ORCPT ); Fri, 14 Aug 2015 03:04:35 -0400 Received: from mx2.suse.de ([195.135.220.15]:44973 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752012AbbHNHEc (ORCPT ); Fri, 14 Aug 2015 03:04:32 -0400 Date: Fri, 14 Aug 2015 17:04:21 +1000 From: NeilBrown To: stable@vger.kernel.org, linux-raid Cc: GuoQing Jiang , Goldwyn Rodrigues , lkml Subject: [PATCH stable] md/bitmap: return an error when bitmap superblock is corrupt. Message-ID: <20150814170421.60d40eb0@noble> X-Mailer: Claws Mail 3.12.0 (GTK+ 2.24.28; x86_64-suse-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1424 Lines: 38 commit b97e92574c0bf335db1cd2ec491d8ff5cd5d0b49 upstream Use separate bitmaps for each nodes in the cluster bitmap_read_sb() validates the bitmap superblock that it reads in. If it finds an inconsistency like a bad magic number or out-of-range version number, it prints an error and returns, but it incorrectly returns zero, so the array is still assembled with the (invalid) bitmap. This means it could try to use a bitmap with a new version number which it therefore does not understand. This bug was introduced in 3.5 and fix as part of a larger patch in 4.1. So the patch is suitable for any -stable kernel in that range. Fixes: 27581e5ae01f ("md/bitmap: centralise allocation of bitmap file pages.") Cc: stable@vger.kernel.org (v3.5..v4.1) Signed-off-by: NeilBrown Reported-by: GuoQing Jiang diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index 3a5767968ba0..894fd58f75f1 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -577,6 +577,8 @@ static int bitmap_read_sb(struct bitmap *bitmap) if (err) return err; + err = -EINVAL; + sb = kmap_atomic(sb_page); chunksize = le32_to_cpu(sb->chunksize); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/