From patchwork Thu May 1 23:17:47 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Darrick Wong X-Patchwork-Id: 344868 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 5BD2A14010A for ; Fri, 2 May 2014 09:17:52 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752688AbaEAXRw (ORCPT ); Thu, 1 May 2014 19:17:52 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:29579 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751014AbaEAXRv (ORCPT ); Thu, 1 May 2014 19:17:51 -0400 Received: from ucsinet22.oracle.com (ucsinet22.oracle.com [156.151.31.94]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id s41NHnpO026205 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 1 May 2014 23:17:50 GMT Received: from userz7021.oracle.com (userz7021.oracle.com [156.151.31.85]) by ucsinet22.oracle.com (8.14.5+Sun/8.14.5) with ESMTP id s41NHnNN012449 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Thu, 1 May 2014 23:17:49 GMT Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by userz7021.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s41NHnTj006344; Thu, 1 May 2014 23:17:49 GMT Received: from localhost (/10.145.179.157) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 01 May 2014 16:17:48 -0700 Subject: [PATCH 4/5] ext4: don't crash when validating block bitmap From: "Darrick J. Wong" To: tytso@mit.edu, darrick.wong@oracle.com Cc: linux-ext4@vger.kernel.org Date: Thu, 01 May 2014 16:17:47 -0700 Message-ID: <20140501231747.892.95073.stgit@birch.djwong.org> In-Reply-To: <20140501231720.892.58712.stgit@birch.djwong.org> References: <20140501231720.892.58712.stgit@birch.djwong.org> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org If EXT4FS_DEBUG is defined, ext4_validate_block_bitmap is called via ext4_count_free_clusters before sb->s_group_info is set up. When this happens, the kernel crashes because group info hasn't been loaded. Forego marking the group corrupt for now; not setting BH_Verified means we'll revisit the bitmap if something went wrong. Signed-off-by: Darrick J. Wong --- fs/ext4/balloc.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 59c3ba8..8f7bed0 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -357,7 +357,10 @@ void ext4_validate_block_bitmap(struct super_block *sb, struct buffer_head *bh) { ext4_fsblk_t blk; - struct ext4_group_info *grp = ext4_get_group_info(sb, block_group); + struct ext4_group_info *grp = NULL; + + if (EXT4_SB(sb)->s_group_info) + grp = ext4_get_group_info(sb, block_group); if (buffer_verified(bh)) return; @@ -368,14 +371,18 @@ void ext4_validate_block_bitmap(struct super_block *sb, ext4_unlock_group(sb, block_group); ext4_error(sb, "bg %u: block %llu: invalid block bitmap", block_group, blk); - set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state); + if (grp) + set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, + &grp->bb_state); return; } if (unlikely(!ext4_block_bitmap_csum_verify(sb, block_group, desc, bh))) { ext4_unlock_group(sb, block_group); ext4_error(sb, "bg %u: bad block bitmap checksum", block_group); - set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state); + if (grp) + set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, + &grp->bb_state); return; } set_buffer_verified(bh);