From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:51800 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753961AbcD0WbR (ORCPT ); Wed, 27 Apr 2016 18:31:17 -0400 Subject: patch "misc: mic: Fix for double fetch security bug in VOP driver" added to char-misc-linus To: ashutosh.dixit@intel.com, gregkh@linuxfoundation.org, stable@vger.kernel.org, sudeep.dutt@intel.com, wpengfeinudt@gmail.com From: Date: Wed, 27 Apr 2016 15:31:16 -0700 Message-ID: <146179627666127@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled misc: mic: Fix for double fetch security bug in VOP driver to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >>From 82dc4afd7e65455464f0fc2fe6976efde54fe451 Mon Sep 17 00:00:00 2001 From: Ashutosh Dixit Date: Wed, 27 Apr 2016 14:36:05 -0700 Subject: misc: mic: Fix for double fetch security bug in VOP driver The MIC VOP driver does two successive reads from user space to read a variable length data structure. Kernel memory corruption can result if the data structure changes between the two reads. This patch disallows the chance of this happening. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=116651 Reported by: Pengfei Wang Reviewed-by: Sudeep Dutt Signed-off-by: Ashutosh Dixit Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/misc/mic/vop/vop_vringh.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c index e94c7fb6712a..88e45234d527 100644 --- a/drivers/misc/mic/vop/vop_vringh.c +++ b/drivers/misc/mic/vop/vop_vringh.c @@ -945,6 +945,11 @@ static long vop_ioctl(struct file *f, unsigned int cmd, unsigned long arg) ret = -EFAULT; goto free_ret; } + /* Ensure desc has not changed between the two reads */ + if (memcmp(&dd, dd_config, sizeof(dd))) { + ret = -EINVAL; + goto free_ret; + } mutex_lock(&vdev->vdev_mutex); mutex_lock(&vi->vop_mutex); ret = vop_virtio_add_device(vdev, dd_config); -- 2.8.0