From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:51980 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751878AbcFWB3K (ORCPT ); Wed, 22 Jun 2016 21:29:10 -0400 Received: from aserv0022.oracle.com (aserv0022.oracle.com [141.146.126.234]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id u5N1T8oU013105 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 23 Jun 2016 01:29:09 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserv0022.oracle.com (8.13.8/8.13.8) with ESMTP id u5N1T86U011030 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 23 Jun 2016 01:29:08 GMT Received: from abhmp0018.oracle.com (abhmp0018.oracle.com [141.146.116.24]) by aserv0122.oracle.com (8.13.8/8.13.8) with ESMTP id u5N1T6Lb023456 for ; Thu, 23 Jun 2016 01:29:07 GMT From: Liu Bo To: linux-btrfs@vger.kernel.org Subject: [PATCH] Btrfs: error out if generic_bin_search get invalid arguments Date: Wed, 22 Jun 2016 18:32:19 -0700 Message-Id: <1466645539-27296-1-git-send-email-bo.li.liu@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: With btrfs-corrupt-block, one can set btree node/leaf's field, if we assign a negative value to node/leaf, we can get various hangs, eg. if extent_root's nritems is -2ULL, then we get stuck in btrfs_read_block_groups() because it has a while loop and btrfs_search_slot() on extent_root will always return the first child. This lets us know what's happening and returns a EINVAL to callers instead of returning the first item. Signed-off-by: Liu Bo --- fs/btrfs/ctree.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index c49a500..915d224 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1770,6 +1770,14 @@ static noinline int generic_bin_search(struct extent_buffer *eb, unsigned long map_len = 0; int err; + if (low > high) { + btrfs_err(eb->fs_info, + "%s: low (%d) < high (%d) eb %llu owner %llu level %d", + __func__, low, high, eb->start, + btrfs_header_owner(eb), btrfs_header_level(eb)); + return -EINVAL; + } + while (low < high) { mid = (low + high) / 2; offset = p + mid * item_size; -- 2.5.5