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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 284F5C10F14 for ; Thu, 3 Oct 2019 17:20:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E89E220830 for ; Thu, 3 Oct 2019 17:20:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570123213; bh=lAXoCvK9UQCg0kKCfkhoaIjzPBFySSpdewTqTsr5tNk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=WIid7fAKONDGWsKDXwdyNLEntLJB4EBCl0YCdeiEUq+RKFG9Xt98cjvTT/IWo5NTw eGqUTXrF8lbkDqOEWt6YLcc0oRxFOlpMuhm7gFvTmgltwsJsrGY0dRErkkY3QqVSjN wbK1ABZRe8h8O97EoBXfzAjI9X2sthcITs/2QCjo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388457AbfJCRT7 (ORCPT ); Thu, 3 Oct 2019 13:19:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:46020 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388239AbfJCQTH (ORCPT ); Thu, 3 Oct 2019 12:19:07 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 838EE21A4C; Thu, 3 Oct 2019 16:19:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570119547; bh=lAXoCvK9UQCg0kKCfkhoaIjzPBFySSpdewTqTsr5tNk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xVsQ5p3un3YSbiPrRw4it2OfkXzmOt5qrMslFD/9w2bpade0vVJpZ89B+pT147YHP HE1kegcwIFZeOPmcY6C4JEN1Nm4Oms4KsoUlOPQzysOVDY4VrSIryQhmojgRtk4E5x j3NNlnrp9blsj8FuY23jikErYWeY9Ag2B/plH1fA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sylwester Nawrocki , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 4.19 104/211] media: ov9650: add a sanity check Date: Thu, 3 Oct 2019 17:52:50 +0200 Message-Id: <20191003154510.531808346@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191003154447.010950442@linuxfoundation.org> References: <20191003154447.010950442@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mauro Carvalho Chehab [ Upstream commit 093347abc7a4e0490e3c962ecbde2dc272a8f708 ] As pointed by cppcheck: [drivers/media/i2c/ov9650.c:706]: (error) Shifting by a negative value is undefined behaviour [drivers/media/i2c/ov9650.c:707]: (error) Shifting by a negative value is undefined behaviour [drivers/media/i2c/ov9650.c:721]: (error) Shifting by a negative value is undefined behaviour Prevent mangling with gains with invalid values. As pointed by Sylvester, this should never happen in practice, as min value of V4L2_CID_GAIN control is 16 (gain is always >= 16 and m is always >= 0), but it is too hard for a static analyzer to get this, as the logic with validates control min/max is elsewhere inside V4L2 core. Reviewed-by: Sylwester Nawrocki Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/i2c/ov9650.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/media/i2c/ov9650.c b/drivers/media/i2c/ov9650.c index 5bea31cd41aa1..33a21d585dc9c 100644 --- a/drivers/media/i2c/ov9650.c +++ b/drivers/media/i2c/ov9650.c @@ -716,6 +716,11 @@ static int ov965x_set_gain(struct ov965x *ov965x, int auto_gain) for (m = 6; m >= 0; m--) if (gain >= (1 << m) * 16) break; + + /* Sanity check: don't adjust the gain with a negative value */ + if (m < 0) + return -EINVAL; + rgain = (gain - ((1 << m) * 16)) / (1 << m); rgain |= (((1 << m) - 1) << 4); -- 2.20.1