From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:58858 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751839AbeEJXOJ (ORCPT ); Thu, 10 May 2018 19:14:09 -0400 From: "Luis R. Rodriguez" To: viro@zeniv.linux.org.uk, darrick.wong@oracle.com, tytso@mit.edu, adilger.kernel@dilger.ca, clm@fb.com, jbacik@fb.com, dsterba@suse.com Cc: sandeen@sandeen.net, dhowells@redhat.com, fliu@suse.com, jack@suse.cz, jeffm@suse.com, nborisov@suse.com, jake.norris@suse.com, mtk.manpages@gmail.com, linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, "Luis R. Rodriguez" Subject: [RFC v2 4/4] btrfs: verify symlinks with append/immutable flags Date: Thu, 10 May 2018 16:13:59 -0700 Message-Id: <20180510231359.16899-5-mcgrof@kernel.org> In-Reply-To: <20180510231359.16899-1-mcgrof@kernel.org> References: <20180510231359.16899-1-mcgrof@kernel.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: The Linux VFS does not allow a way to set append/immuttable attributes to symlinks, this is just not possible. If this is detected inform the user as the filesystem must be corrupted. Signed-off-by: Luis R. Rodriguez --- fs/btrfs/inode.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index c4bdb597b323..d9c786be408c 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3933,6 +3933,15 @@ static int btrfs_read_locked_inode(struct inode *inode) inode->i_op = &btrfs_dir_inode_operations; break; case S_IFLNK: + /* VFS does not allow setting these so must be corruption */ + if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) { + ret = -EUCLEAN; + btrfs_crit(fs_info, + "corrupt symlink with append/immutable ino=%llu root=%llu\n", + btrfs_ino(BTRFS_I(inode)), + root->root_key.objectid); + goto make_bad; + } inode->i_op = &btrfs_symlink_inode_operations; inode_nohighmem(inode); inode->i_mapping->a_ops = &btrfs_symlink_aops; -- 2.17.0