From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932369AbcEKQcI (ORCPT ); Wed, 11 May 2016 12:32:08 -0400 Received: from lists.s-osg.org ([54.187.51.154]:47174 "EHLO lists.s-osg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751632AbcEKQcF (ORCPT ); Wed, 11 May 2016 12:32:05 -0400 Date: Wed, 11 May 2016 13:31:59 -0300 From: Mauro Carvalho Chehab To: Greg Kroah-Hartman Cc: , , Sakari Ailus , Hans Verkuil Subject: Re: [PATCH 4.5 118/200] [media] videobuf2-v4l2: Verify planes array in buffer dequeueing Message-ID: <20160511133159.54bb5ee9@recife.lan> In-Reply-To: <20160503000558.479164865@linuxfoundation.org> References: <20160503000554.631204776@linuxfoundation.org> <20160503000558.479164865@linuxfoundation.org> Organization: Samsung X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Greg, This patch seems to be causing trobles with DVB drivers that uses videobuf2-dvb. Just sent a patch reverting it. Regards, Mauro Em Mon, 2 May 2016 17:11:57 -0700 Greg Kroah-Hartman escreveu: > 4.5-stable review patch. If anyone has any objections, please let me know. > > ------------------ > > From: Sakari Ailus > > commit 2c1f6951a8a82e6de0d82b1158b5e493fc6c54ab upstream. > > When a buffer is being dequeued using VIDIOC_DQBUF IOCTL, the exact buffer > which will be dequeued is not known until the buffer has been removed from > the queue. The number of planes is specific to a buffer, not to the queue. > > This does lead to the situation where multi-plane buffers may be requested > and queued with n planes, but VIDIOC_DQBUF IOCTL may be passed an argument > struct with fewer planes. > > __fill_v4l2_buffer() however uses the number of planes from the dequeued > videobuf2 buffer, overwriting kernel memory (the m.planes array allocated > in video_usercopy() in v4l2-ioctl.c) if the user provided fewer > planes than the dequeued buffer had. Oops! > > Fixes: b0e0e1f83de3 ("[media] media: videobuf2: Prepare to divide videobuf2") > > Signed-off-by: Sakari Ailus > Acked-by: Hans Verkuil > Signed-off-by: Mauro Carvalho Chehab > Signed-off-by: Greg Kroah-Hartman > > --- > drivers/media/v4l2-core/videobuf2-v4l2.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > --- a/drivers/media/v4l2-core/videobuf2-v4l2.c > +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c > @@ -74,6 +74,11 @@ static int __verify_planes_array(struct > return 0; > } > > +static int __verify_planes_array_core(struct vb2_buffer *vb, const void *pb) > +{ > + return __verify_planes_array(vb, pb); > +} > + > /** > * __verify_length() - Verify that the bytesused value for each plane fits in > * the plane length and that the data offset doesn't exceed the bytesused value. > @@ -437,6 +442,7 @@ static int __fill_vb2_buffer(struct vb2_ > } > > static const struct vb2_buf_ops v4l2_buf_ops = { > + .verify_planes_array = __verify_planes_array_core, > .fill_user_buffer = __fill_v4l2_buffer, > .fill_vb2_buffer = __fill_vb2_buffer, > .copy_timestamp = __copy_timestamp, > > -- Thanks, Mauro