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 93E2DC433EF for ; Mon, 20 Dec 2021 15:11:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240839AbhLTPLY (ORCPT ); Mon, 20 Dec 2021 10:11:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38570 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239714AbhLTPJZ (ORCPT ); Mon, 20 Dec 2021 10:09:25 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0D31EC0698C7; Mon, 20 Dec 2021 06:54:56 -0800 (PST) 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 dfw.source.kernel.org (Postfix) with ESMTPS id A15D46118D; Mon, 20 Dec 2021 14:54:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 85A33C36AE8; Mon, 20 Dec 2021 14:54:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1640012095; bh=MelOGxsUvzgPtXNlFclQLBgW3ihg6esYfZvXOhm5kuQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eO6vCmFECZDR/LLsC+++zIGW3O3bsPeQWNOSP2LB1/XRa+vXG26R92puudpevzibH avevysiLO2dwlpZpaSKsgWzj9xXfxSJ/VU+pud9I/SU4ms/+n6NZqw43/nCs7SAOLW oQGYNkUwhhyb46uTYKl5OOtWX3YfOOV7I6PvcpnE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Harshit Mogalapalli , Lucas De Marchi , Rodrigo Vivi , Sasha Levin Subject: [PATCH 5.15 079/177] drm/i915/display: Fix an unsigned subtraction which can never be negative. Date: Mon, 20 Dec 2021 15:33:49 +0100 Message-Id: <20211220143042.765700556@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211220143040.058287525@linuxfoundation.org> References: <20211220143040.058287525@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Harshit Mogalapalli [ Upstream commit 53b3495273282aa844c4613d19c3b30558c70c84 ] smatch warning: drivers/gpu/drm/i915/display/intel_dmc.c:601 parse_dmc_fw() warn: unsigned 'fw->size - offset' is never less than zero Firmware size is size_t and offset is u32. So the subtraction is unsigned which can never be less than zero. Fixes: 3d5928a168a9 ("drm/i915/xelpd: Pipe A DMC plugging") Signed-off-by: Harshit Mogalapalli Reviewed-by: Lucas De Marchi Signed-off-by: Lucas De Marchi Link: https://patchwork.freedesktop.org/patch/msgid/20211210044129.12422-1-harshit.m.mogalapalli@oracle.com (cherry picked from commit 87bb2a410dcfb617b88e4695edf4beb6336dc314) Signed-off-by: Rodrigo Vivi Signed-off-by: Sasha Levin --- drivers/gpu/drm/i915/display/intel_dmc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_dmc.c b/drivers/gpu/drm/i915/display/intel_dmc.c index b3c8e1c450efb..73076737add75 100644 --- a/drivers/gpu/drm/i915/display/intel_dmc.c +++ b/drivers/gpu/drm/i915/display/intel_dmc.c @@ -606,7 +606,7 @@ static void parse_dmc_fw(struct drm_i915_private *dev_priv, continue; offset = readcount + dmc->dmc_info[id].dmc_offset * 4; - if (fw->size - offset < 0) { + if (offset > fw->size) { drm_err(&dev_priv->drm, "Reading beyond the fw_size\n"); continue; } -- 2.33.0