From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , "Darrick J. Wong" , Dave Chinner , Dave Chinner , Christoph Hellwig Subject: [PATCH 4.9 193/206] xfs: check for bogus values in btree block headers Date: Tue, 10 Jan 2017 14:37:56 +0100 Message-Id: <20170110131511.894439224@linuxfoundation.org> In-Reply-To: <20170110131502.767555407@linuxfoundation.org> References: <20170110131502.767555407@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Darrick J. Wong" commit bb3be7e7c1c18e1b141d4cadeb98cc89ecf78099 upstream. When we're reading a btree block, make sure that what we retrieved matches the owner and level; and has a plausible number of records. Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner Cc: Christoph Hellwig Signed-off-by: Greg Kroah-Hartman --- fs/xfs/libxfs/xfs_btree.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) --- a/fs/xfs/libxfs/xfs_btree.c +++ b/fs/xfs/libxfs/xfs_btree.c @@ -1769,8 +1769,28 @@ xfs_btree_lookup_get_block( if (error) return error; + /* Check the inode owner since the verifiers don't. */ + if (xfs_sb_version_hascrc(&cur->bc_mp->m_sb) && + (cur->bc_flags & XFS_BTREE_LONG_PTRS) && + be64_to_cpu((*blkp)->bb_u.l.bb_owner) != + cur->bc_private.b.ip->i_ino) + goto out_bad; + + /* Did we get the level we were looking for? */ + if (be16_to_cpu((*blkp)->bb_level) != level) + goto out_bad; + + /* Check that internal nodes have at least one record. */ + if (level != 0 && be16_to_cpu((*blkp)->bb_numrecs) == 0) + goto out_bad; + xfs_btree_setbuf(cur, level, bp); return 0; + +out_bad: + *blkp = NULL; + xfs_trans_brelse(cur->bc_tp, bp); + return -EFSCORRUPTED; } /*