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 C90D1C6FD1C for ; Wed, 22 Mar 2023 20:12:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232135AbjCVUMk (ORCPT ); Wed, 22 Mar 2023 16:12:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232022AbjCVUMQ (ORCPT ); Wed, 22 Mar 2023 16:12:16 -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 0BA7B7E8AE; Wed, 22 Mar 2023 13:04:18 -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 5183FB81DE2; Wed, 22 Mar 2023 20:03:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D1CFC433A1; Wed, 22 Mar 2023 20:03:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679515409; bh=K0x3SRRa4HXHn+EKwSF6/erKOQgcKi+VGbc7NR6slpo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZciWCCcQyE9Ueoepcl8Jmm3m3zhIlW6waxD8sYKz5anWRQjcbCQwfg+pmt5uD25Lo ksadbrbxl1HmE+sLdzL2Ev1ot5+pZOdlV8o84ZQvV+vFjdHhu9zO38MExqvK6B/BYO MlBN33md8IE5iGgREm38PreXAmm3hd0U5vHuVr1b5rl1U9PwbTcd+vAxHW083gvKVE XDHs8Oao/7KpKwBGKI3r5egZbXh2n+4NEzfSIv9FnuVDhX3KKRw+CZdoJiN6jW2mIb pnSW8iT8H9c4d4/sORbj6ugRtzcgbDdf7KvbC08BIR9zb55SuuhGCpC1xfJAzxlUqC 8T03P9KxGJFQw== 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 4.19 6/9] fbdev: nvidia: Fix potential divide by zero Date: Wed, 22 Mar 2023 16:03:06 -0400 Message-Id: <20230322200309.1997651-6-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230322200309.1997651-1-sashal@kernel.org> References: <20230322200309.1997651-1-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 fbeeed5afe350..aa502b3ba25ae 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