From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:32912 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727615AbeIYJGE (ORCPT ); Tue, 25 Sep 2018 05:06:04 -0400 Subject: [PATCH 2/2 V3] xfs: verify size-vs-format for symlinks & dirs References: From: Eric Sandeen Message-ID: <1e55b111-eae4-b0cf-0221-c96eb3f17b77@redhat.com> Date: Mon, 24 Sep 2018 22:00:39 -0500 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Eric Sandeen , linux-xfs Cc: "Xu, Wen" Today, xfs_ifork_verify_data() will simply skip verification if the inode claims to be in non-local format. However, nothing catches the case where the size for the format is too small to be non-local. xfs_repair tests for this mismatch in process_check_inode_sizes(), so do the same in this verifier. Reported-by: Xu, Wen Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200925 Signed-off-by: Eric Sandeen Reviewed-by: Brian Foster --- V2: restructure code & tests per Dave's suggestion on the V1 patch. V3: rewrite dave's comments per brian's suggestions diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c index f9acf1d436f6..d1a58e7a872f 100644 --- a/fs/xfs/libxfs/xfs_inode_fork.c +++ b/fs/xfs/libxfs/xfs_inode_fork.c @@ -704,12 +704,33 @@ xfs_ifork_verify_data( struct xfs_inode *ip, struct xfs_ifork_ops *ops) { - /* Non-local data fork, we're done. */ - if (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL) + struct xfs_mount *mp = ip->i_mount; + int mode = VFS_I(ip)->i_mode; + + /* + * Verify non-local format forks have a valid size. Symlinks must have + * outgrown the data fork size. The same goes for non-local dirs, but + * dirs grow at dirblock granularity. Perform a slightly stronger check + * and require the dir is at least one dirblock in size. + */ + if (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL) { + switch (mode & S_IFMT) { + case S_IFDIR: + if (ip->i_d.di_size < mp->m_dir_geo->blksize) + return __this_address; + break; + case S_IFLNK: + if (ip->i_d.di_size <= XFS_IFORK_DSIZE(ip)) + return __this_address; + break; + default: + break; + } return NULL; + } /* Check the inline data fork if there is one. */ - switch (VFS_I(ip)->i_mode & S_IFMT) { + switch (mode & S_IFMT) { case S_IFDIR: return ops->verify_dir(ip); case S_IFLNK: