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 74C5EC76188 for ; Mon, 3 Apr 2023 14:32:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233502AbjDCOc1 (ORCPT ); Mon, 3 Apr 2023 10:32:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36912 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233509AbjDCOcZ (ORCPT ); Mon, 3 Apr 2023 10:32:25 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE2D6D4FAF for ; Mon, 3 Apr 2023 07:32:20 -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 2086FB81C6C for ; Mon, 3 Apr 2023 14:32:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60B62C433D2; Mon, 3 Apr 2023 14:32:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680532338; bh=L0ppsVkM3L1IhzDIY/wbSoHkSWthJizIcAiKa9RNvfk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eDAxjnjvFkzo/f7Z67dIV65JR/A5KyXCb4m5Y2hz6uPQXI2w99rvcjCq+//FiZ1GZ N8QkfpZXB4eOP/dUNH4saEYQYgAEkb22tjql1tUuX06zzbLx6SUjSGVcP4qvR8KNWG 40wd2bXIN7Q6VbPmtY/3VLwR1DkQtO4yfJIQ6qsg= 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 5.15 17/99] fbdev: nvidia: Fix potential divide by zero Date: Mon, 3 Apr 2023 16:08:40 +0200 Message-Id: <20230403140359.980471288@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230403140356.079638751@linuxfoundation.org> References: <20230403140356.079638751@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 a372a183c1f01..f9c388a8c10e3 100644 --- a/drivers/video/fbdev/nvidia/nvidia.c +++ b/drivers/video/fbdev/nvidia/nvidia.c @@ -763,6 +763,8 @@ 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