From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3D471C83013 for ; Wed, 2 Dec 2020 15:19:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE03421741 for ; Wed, 2 Dec 2020 15:19:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387449AbgLBPTg convert rfc822-to-8bit (ORCPT ); Wed, 2 Dec 2020 10:19:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50352 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387399AbgLBPTg (ORCPT ); Wed, 2 Dec 2020 10:19:36 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7BE9CC061A4A for ; Wed, 2 Dec 2020 07:18:53 -0800 (PST) Received: from lupine.hi.pengutronix.de ([2001:67c:670:100:3ad5:47ff:feaf:1a17] helo=lupine) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1kkTu0-0007l1-PA; Wed, 02 Dec 2020 16:18:44 +0100 Received: from pza by lupine with local (Exim 4.92) (envelope-from ) id 1kkTu0-0007Qi-7W; Wed, 02 Dec 2020 16:18:44 +0100 Message-ID: <2dfd7785da904e9b518a0e7579d4db79a0b19276.camel@pengutronix.de> Subject: Re: [PATCH v5 08/10] media: Quit parsing stream if doesn't start with SOI From: Philipp Zabel To: "Mirela Rabulea (OSS)" , mchehab@kernel.org, hverkuil-cisco@xs4all.nl, shawnguo@kernel.org, robh+dt@kernel.org Cc: paul.kocialkowski@bootlin.com, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-imx@nxp.com, s.hauer@pengutronix.de, aisheng.dong@nxp.com, daniel.baluta@nxp.com, robert.chiras@nxp.com, laurentiu.palcu@nxp.com, mark.rutland@arm.com, devicetree@vger.kernel.org, ezequiel@collabora.com, laurent.pinchart+renesas@ideasonboard.com, niklas.soderlund+renesas@ragnatech.se, dafna.hirschfeld@collabora.com, Mirela Rabulea Date: Wed, 02 Dec 2020 16:18:44 +0100 In-Reply-To: <20201112030557.8540-9-mirela.rabulea@oss.nxp.com> References: <20201112030557.8540-1-mirela.rabulea@oss.nxp.com> <20201112030557.8540-9-mirela.rabulea@oss.nxp.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT User-Agent: Evolution 3.30.5-1.1 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:3ad5:47ff:feaf:1a17 X-SA-Exim-Mail-From: p.zabel@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: devicetree@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Thu, 2020-11-12 at 05:05 +0200, Mirela Rabulea (OSS) wrote: > From: Mirela Rabulea > > In the case we get an invalid stream, such as from v4l2-compliance > streaming test, jpeg_next_marker will end up parsing the entire > stream. The standard describes the high level syntax of a jpeg > as starting with SOI, ending with EOI, so return error if the very > first 2 bytes are not SOI. > > Signed-off-by: Mirela Rabulea > --- > drivers/media/v4l2-core/v4l2-jpeg.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/media/v4l2-core/v4l2-jpeg.c b/drivers/media/v4l2-core/v4l2-jpeg.c > index 3181ce544f79..d77e04083d57 100644 > --- a/drivers/media/v4l2-core/v4l2-jpeg.c > +++ b/drivers/media/v4l2-core/v4l2-jpeg.c > @@ -499,11 +499,8 @@ int v4l2_jpeg_parse_header(void *buf, size_t len, struct v4l2_jpeg_header *out) > out->num_dht = 0; > out->num_dqt = 0; > > - /* the first marker must be SOI */ > - marker = jpeg_next_marker(&stream); > - if (marker < 0) > - return marker; > - if (marker != SOI) > + /* the first bytes must be SOI, B.2.1 High-level syntax */ > + if (jpeg_get_word_be(&stream) != SOI) > return -EINVAL; > > /* init value to signal if this marker is not present */ Yes, shorter, potentially faster code, and it adheres to the specification more strictly. Reviewed-by: Philipp Zabel regards Philipp