From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1768456AbcHROrW (ORCPT ); Thu, 18 Aug 2016 10:47:22 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36816 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1767853AbcHROKy (ORCPT ); Thu, 18 Aug 2016 10:10:54 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David R , Sakari Ailus , Hans Verkuil , Mauro Carvalho Chehab Subject: [PATCH 4.7 045/186] [media] vb2: core: Skip planes array verification if pb is NULL Date: Thu, 18 Aug 2016 15:57:42 +0200 Message-Id: <20160818135934.094883196@linuxfoundation.org> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20160818135932.219369981@linuxfoundation.org> References: <20160818135932.219369981@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 4.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sakari Ailus commit 126f40298446a82116e1f92a1aaf72b8c8228fae upstream. An earlier patch fixing an input validation issue introduced another issue: vb2_core_dqbuf() is called with pb argument value NULL in some cases, causing a NULL pointer dereference. Fix this by skipping the verification as there's nothing to verify. Fixes: e7e0c3e26587 ("[media] videobuf2-core: Check user space planes array in dqbuf") Signed-off-by: David R Signed-off-by: Sakari Ailus Reviewed-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/v4l2-core/videobuf2-core.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/drivers/media/v4l2-core/videobuf2-core.c +++ b/drivers/media/v4l2-core/videobuf2-core.c @@ -1648,7 +1648,7 @@ static int __vb2_get_done_vb(struct vb2_ void *pb, int nonblocking) { unsigned long flags; - int ret; + int ret = 0; /* * Wait for at least one buffer to become available on the done_list. @@ -1664,10 +1664,12 @@ static int __vb2_get_done_vb(struct vb2_ spin_lock_irqsave(&q->done_lock, flags); *vb = list_first_entry(&q->done_list, struct vb2_buffer, done_entry); /* - * Only remove the buffer from done_list if v4l2_buffer can handle all - * the planes. + * Only remove the buffer from done_list if all planes can be + * handled. Some cases such as V4L2 file I/O and DVB have pb + * == NULL; skip the check then as there's nothing to verify. */ - ret = call_bufop(q, verify_planes_array, *vb, pb); + if (pb) + ret = call_bufop(q, verify_planes_array, *vb, pb); if (!ret) list_del(&(*vb)->done_entry); spin_unlock_irqrestore(&q->done_lock, flags);