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 1D2AFC76196 for ; Mon, 3 Apr 2023 14:17:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232956AbjDCORH (ORCPT ); Mon, 3 Apr 2023 10:17:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232965AbjDCORG (ORCPT ); Mon, 3 Apr 2023 10:17:06 -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 003DE27831 for ; Mon, 3 Apr 2023 07:17:05 -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 A28B6B81B8A for ; Mon, 3 Apr 2023 14:17:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A3D3C433EF; Mon, 3 Apr 2023 14:17:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680531423; bh=K0x3SRRa4HXHn+EKwSF6/erKOQgcKi+VGbc7NR6slpo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YUKD5+MglZYb5z5GRZ+8usaAbybx4ej/EJ219aZtNQtylbVsmrv7wxD18YOVHa71/ /nY9psvLTX4OxmHckUjd9KPhmzs1ZLkDKstSfEJKy0wa+m+p1B/6Wt/fdRJS8DhY/f 78LJebui6sOvpnV0KYEXP4MOqF/ywr8e0pG2LTvs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Wei Chen , Helge Deller , Sasha Levin Subject: [PATCH 4.19 57/84] fbdev: nvidia: Fix potential divide by zero Date: Mon, 3 Apr 2023 16:08:58 +0200 Message-Id: <20230403140355.388761058@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230403140353.406927418@linuxfoundation.org> References: <20230403140353.406927418@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@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