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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8463C6FD1C for ; Wed, 22 Mar 2023 20:14:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232234AbjCVUOG (ORCPT ); Wed, 22 Mar 2023 16:14:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231272AbjCVUNn (ORCPT ); Wed, 22 Mar 2023 16:13:43 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8310372006; Wed, 22 Mar 2023 13:05:03 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B17B8B81DF6; Wed, 22 Mar 2023 20:03:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9A3E1C4339B; Wed, 22 Mar 2023 20:03:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679515436; bh=ko5ax+OAK5fAVAAVNTrQOuTVQCrHkrQbCobV2lkkRPw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uCx6TxbeOQajWKWbsg+4D62msHM9dkiva35S9SvicOaBkLqRjE69jgSVpmOB/Raot tPzuVJnr6S8YPlxI8VpbwTnz4OM5JXYv55uXs1yqoLg4rZMQHuK5RDy7sudpdmDifT eBRY7Ds3Pq5SV3b5ojgp5hGPE6oopvTkCr68Qbg42B+E+prwzTYOe5Kvw1yjFJ3oZw XtAx12HmOe5q1/FI/3SQS51d1IJpLxTIfN0m5ronYW1/f41MTeNrkTKnfaunfDwmlv WDvPgtCJsnGzYLxopDfn+HuKRx9KGwdAiXq5taFkuyjn30hVapTrmKVr6V7Z968Bxd 1iLMKaUwe/sBA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Wei Chen , Helge Deller , Sasha Levin , adaplas@gmail.com, linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: [PATCH AUTOSEL 4.14 6/9] fbdev: nvidia: Fix potential divide by zero Date: Wed, 22 Mar 2023 16:03:33 -0400 Message-Id: <20230322200337.1997810-6-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230322200337.1997810-1-sashal@kernel.org> References: <20230322200337.1997810-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org From: Wei Chen [ Upstream commit 92e2a00f2987483e1f9253625828622edd442e61 ] variable var->pixclock can be set by user. In case it equals to zero, divide by zero would occur in nvidiafb_set_par. Similar crashes have happened in other fbdev drivers. There is no check and modification on var->pixclock along the call chain to nvidia_check_var and nvidiafb_set_par. We believe it could also be triggered in driver nvidia from user site. Signed-off-by: Wei Chen Signed-off-by: Helge Deller Signed-off-by: Sasha Levin --- drivers/video/fbdev/nvidia/nvidia.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/video/fbdev/nvidia/nvidia.c b/drivers/video/fbdev/nvidia/nvidia.c index 418a2d0d06a95..68e4bcdd38717 100644 --- a/drivers/video/fbdev/nvidia/nvidia.c +++ b/drivers/video/fbdev/nvidia/nvidia.c @@ -766,6 +766,8 @@ static int nvidiafb_check_var(struct fb_var_screeninfo *var, int pitch, err = 0; NVTRACE_ENTER(); + if (!var->pixclock) + return -EINVAL; var->transp.offset = 0; var->transp.length = 0; -- 2.39.2