From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753303AbcI1JKU (ORCPT ); Wed, 28 Sep 2016 05:10:20 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:57522 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932369AbcI1JJU (ORCPT ); Wed, 28 Sep 2016 05:09:20 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jeff Mahoney , Chris Mason Subject: [PATCH 4.4 58/73] btrfs: ensure that file descriptor used with subvol ioctls is a dir Date: Wed, 28 Sep 2016 11:05:28 +0200 Message-Id: <20160928090438.213138318@linuxfoundation.org> X-Mailer: git-send-email 2.10.0 In-Reply-To: <20160928090434.509091655@linuxfoundation.org> References: <20160928090434.509091655@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Mahoney commit 325c50e3cebb9208009083e841550f98a863bfa0 upstream. If the subvol/snapshot create/destroy ioctls are passed a regular file with execute permissions set, we'll eventually Oops while trying to do inode->i_op->lookup via lookup_one_len. This patch ensures that the file descriptor refers to a directory. Fixes: cb8e70901d (Btrfs: Fix subvolume creation locking rules) Fixes: 76dda93c6a (Btrfs: add snapshot/subvolume destroy ioctl) Signed-off-by: Jeff Mahoney Signed-off-by: Chris Mason Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/ioctl.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1619,6 +1619,9 @@ static noinline int btrfs_ioctl_snap_cre int namelen; int ret = 0; + if (!S_ISDIR(file_inode(file)->i_mode)) + return -ENOTDIR; + ret = mnt_want_write_file(file); if (ret) goto out; @@ -1676,6 +1679,9 @@ static noinline int btrfs_ioctl_snap_cre struct btrfs_ioctl_vol_args *vol_args; int ret; + if (!S_ISDIR(file_inode(file)->i_mode)) + return -ENOTDIR; + vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) return PTR_ERR(vol_args); @@ -1699,6 +1705,9 @@ static noinline int btrfs_ioctl_snap_cre bool readonly = false; struct btrfs_qgroup_inherit *inherit = NULL; + if (!S_ISDIR(file_inode(file)->i_mode)) + return -ENOTDIR; + vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) return PTR_ERR(vol_args); @@ -2345,6 +2354,9 @@ static noinline int btrfs_ioctl_snap_des int ret; int err = 0; + if (!S_ISDIR(dir->i_mode)) + return -ENOTDIR; + vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) return PTR_ERR(vol_args);