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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 B82D2C352A3 for ; Mon, 10 Feb 2020 13:00:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8493E20708 for ; Mon, 10 Feb 2020 13:00:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581339620; bh=mER//Xvie/6H/Xs1QdZ3VlSUenuLA157YBjo4JLRCJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=EJPRNcHCI4t4+i6rzDefuDGnncAcel08zdusNNEjMF+uqqaCp7P9aghv8S3yG4GRF 8NbWz1gEXpWakVsqQj8FDHsB68U9VbkQUEehPnOJL0ki0dIPRAJivKgqE8yVYWRxXl EONmxO2/+XTP7qCPZhzvmbmXPxrXnLUZFovr9y5k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730273AbgBJNAT (ORCPT ); Mon, 10 Feb 2020 08:00:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:42070 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729555AbgBJMlA (ORCPT ); Mon, 10 Feb 2020 07:41:00 -0500 Received: from localhost (unknown [209.37.97.194]) (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 8BB1E20838; Mon, 10 Feb 2020 12:40:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581338459; bh=mER//Xvie/6H/Xs1QdZ3VlSUenuLA157YBjo4JLRCJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s3SYkS3MyQSRvOGtft/66WAyQn8kcVgwthUwm6HuwOxjaDMufhj/3gAAJL5anIL6t yD7oybRq9WA/ZjWgxtZdJ7AbP7t+OmhhPE4QXnAaEL4Th9E737Du+R9QkKs9PlVs/R v8ji1dnLj6r4H2lRV7wOKS4Kp2/adKK8JKneVMbA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Maarten Lankhorst , Benjamin Gaignard , Daniel Vetter , =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Daniel Vetter Subject: [PATCH 5.5 215/367] drm/rect: Avoid division by zero Date: Mon, 10 Feb 2020 04:32:08 -0800 Message-Id: <20200210122444.083805445@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200210122423.695146547@linuxfoundation.org> References: <20200210122423.695146547@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ville Syrjälä commit 433480c1afd44f3e1e664b85063d98cefeefa0ed upstream. Check for zero width/height destination rectangle in drm_rect_clip_scaled() to avoid a division by zero. Cc: stable@vger.kernel.org Fixes: f96bdf564f3e ("drm/rect: Handle rounding errors in drm_rect_clip_scaled, v3.") Cc: Maarten Lankhorst Cc: Benjamin Gaignard Cc: Daniel Vetter Testcase: igt/kms_selftest/drm_rect_clip_scaled_div_by_zero Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20191122175623.13565-2-ville.syrjala@linux.intel.com Reviewed-by: Daniel Vetter Reviewed-by: Benjamin Gaignard Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_rect.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/drm_rect.c +++ b/drivers/gpu/drm/drm_rect.c @@ -54,7 +54,12 @@ EXPORT_SYMBOL(drm_rect_intersect); static u32 clip_scaled(u32 src, u32 dst, u32 clip) { - u64 tmp = mul_u32_u32(src, dst - clip); + u64 tmp; + + if (dst == 0) + return 0; + + tmp = mul_u32_u32(src, dst - clip); /* * Round toward 1.0 when clipping so that we don't accidentally