From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932523AbcELMPN (ORCPT ); Thu, 12 May 2016 08:15:13 -0400 Received: from nblzone-211-213.nblnetworks.fi ([83.145.211.213]:35260 "EHLO hillosipuli.retiisi.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932441AbcELMPI (ORCPT ); Thu, 12 May 2016 08:15:08 -0400 From: Sakari Ailus To: linux-media@vger.kernel.org Cc: mchehab@osg.samsung.com, hverkuil@xs4all.nl, david@unsolicited.net, linux-kernel@vger.kernel.org, Sakari Ailus Subject: [PATCH v2 1/2] vb2: core: Skip planes array verification if pb is NULL Date: Thu, 12 May 2016 15:14:51 +0300 Message-Id: <1463055292-25053-2-git-send-email-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1463055292-25053-1-git-send-email-sakari.ailus@linux.intel.com> References: <1463055292-25053-1-git-send-email-sakari.ailus@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Signed-off-by: David R Use if () instead of ? :; it's nicer that way. Improve the comment in the code as well. Fixes: e7e0c3e26587 ("[media] videobuf2-core: Check user space planes array in dqbuf") Signed-off-by: Sakari Ailus Cc: stable@vger.kernel.org # for v4.4 and later --- drivers/media/v4l2-core/videobuf2-core.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c index 9fbcb67..633fc1a 100644 --- 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_queue *q, struct vb2_buffer **vb, 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_queue *q, struct vb2_buffer **vb, 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); -- 2.1.4