From patchwork Mon Oct 30 17:14:38 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Bo X-Patchwork-Id: 10033007 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A392660291 for ; Mon, 30 Oct 2017 18:17:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9ED6D2837E for ; Mon, 30 Oct 2017 18:17:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 93B212854F; Mon, 30 Oct 2017 18:17:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1AD0E2837E for ; Mon, 30 Oct 2017 18:17:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932792AbdJ3SRI (ORCPT ); Mon, 30 Oct 2017 14:17:08 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:51548 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932716AbdJ3SRG (ORCPT ); Mon, 30 Oct 2017 14:17:06 -0400 Received: from userv0021.oracle.com (userv0021.oracle.com [156.151.31.71]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id v9UIH5q5014997 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Mon, 30 Oct 2017 18:17:06 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by userv0021.oracle.com (8.14.4/8.14.4) with ESMTP id v9UIH5BZ012881 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Mon, 30 Oct 2017 18:17:05 GMT Received: from abhmp0016.oracle.com (abhmp0016.oracle.com [141.146.116.22]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id v9UIH5VE006145 for ; Mon, 30 Oct 2017 18:17:05 GMT Received: from dhcp-10-211-47-181.usdhcp.oraclecorp.com.com (/10.211.47.181) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 30 Oct 2017 11:17:05 -0700 From: Liu Bo To: linux-btrfs@vger.kernel.org Subject: [PATCH] Btrfs: bail out gracefully rather than BUG_ON Date: Mon, 30 Oct 2017 11:14:38 -0600 Message-Id: <20171030171440.27044-1-bo.li.liu@oracle.com> X-Mailer: git-send-email 2.9.4 X-Source-IP: userv0021.oracle.com [156.151.31.71] Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If a file's DIR_ITEM key is invalid (due to memory errors) and gets written to disk, a future lookup_path can end up with kernel panic due to BUG_ON(). This gets rid of the BUG_ON(), meanwhile output the corrupted key and return ENOENT if it's invalid. Signed-off-by: Liu Bo Reported-by: Guillaume Bouchard Reviewed-by: David Sterba --- The diff doesn't show the logic well, 'goto out_err' will return with assigning 0 to location->objectid, and the caller already has a check for (location->objectid == 0) to return -ENOENT. fs/btrfs/inode.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index d94e3f6..916cdc9 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5500,6 +5500,14 @@ static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry, goto out_err; btrfs_dir_item_key_to_cpu(path->nodes[0], di, location); + if (location->type != BTRFS_INODE_ITEM_KEY && + location->type != BTRFS_ROOT_ITEM_KEY) { + btrfs_warn(root->fs_info, + "%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))", + __func__, name, btrfs_ino(BTRFS_I(dir)), + location->objectid, location->type, location->offset); + goto out_err; + } out: btrfs_free_path(path); return ret; @@ -5816,8 +5824,6 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) return inode; } - BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY); - index = srcu_read_lock(&fs_info->subvol_srcu); ret = fixup_tree_root_location(fs_info, dir, dentry, &location, &sub_root);