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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 14338C5B57D for ; Wed, 3 Jul 2019 02:18:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D30962187F for ; Wed, 3 Jul 2019 02:18:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562120325; bh=uENfrnc36wGwGmfUs3kHW+aKKK8OHMXgfYO50WXB/Rc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=L8J7HZsuQ0o8unjM1HIgLaAAGUEPPsberwDAydCHoBTUu7DeHKPr9fuC/7gbED+rv r0pbMGMxK/MfSH6Gz1w4YLn2JXRkWz61fvNpIy8h0DVQzvMJH2F21uU7DUPr2s2MvM k0Eg/pcscjVaTTP3LeHIuR2eUWl3vxtbm3dy32N8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728297AbfGCCSo (ORCPT ); Tue, 2 Jul 2019 22:18:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:56488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728043AbfGCCSf (ORCPT ); Tue, 2 Jul 2019 22:18:35 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 498A12187F; Wed, 3 Jul 2019 02:18:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562120314; bh=uENfrnc36wGwGmfUs3kHW+aKKK8OHMXgfYO50WXB/Rc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VLFDFdrcO4LZbS5gCOXE1JxfN52ElbD56eb/IxjvsSwnNy/hL6M/RQE/xHug7zmb5 z//w8s0+a+WBtK+CB0i0NsUUW7C3SdTxKx7JNcXeSmq6a+Q6HrdGj6W+r0Pc7/a1oy eA/DGFXOYrGHtVF7StdeInQBTpmGFOcf/Km/Cxsg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vinod Koul , Andrew Morton , Bjorn Andersson , Randy Dunlap , Linus Torvalds , Sasha Levin Subject: [PATCH AUTOSEL 4.14 13/13] linux/kernel.h: fix overflow for DIV_ROUND_UP_ULL Date: Tue, 2 Jul 2019 22:18:14 -0400 Message-Id: <20190703021814.18385-13-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190703021814.18385-1-sashal@kernel.org> References: <20190703021814.18385-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vinod Koul [ Upstream commit 8f9fab480c7a87b10bb5440b5555f370272a5d59 ] DIV_ROUND_UP_ULL adds the two arguments and then invokes DIV_ROUND_DOWN_ULL. But on a 32bit system the addition of two 32 bit values can overflow. DIV_ROUND_DOWN_ULL does it correctly and stashes the addition into a unsigned long long so cast the result to unsigned long long here to avoid the overflow condition. [akpm@linux-foundation.org: DIV_ROUND_UP_ULL must be an rval] Link: http://lkml.kernel.org/r/20190625100518.30753-1-vkoul@kernel.org Signed-off-by: Vinod Koul Reviewed-by: Andrew Morton Cc: Bjorn Andersson Cc: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- include/linux/kernel.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 1c5469adaa85..bb7baecef002 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -101,7 +101,8 @@ #define DIV_ROUND_DOWN_ULL(ll, d) \ ({ unsigned long long _tmp = (ll); do_div(_tmp, d); _tmp; }) -#define DIV_ROUND_UP_ULL(ll, d) DIV_ROUND_DOWN_ULL((ll) + (d) - 1, (d)) +#define DIV_ROUND_UP_ULL(ll, d) \ + DIV_ROUND_DOWN_ULL((unsigned long long)(ll) + (d) - 1, (d)) #if BITS_PER_LONG == 32 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d) -- 2.20.1