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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=ham 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 53163C282C4 for ; Wed, 13 Feb 2019 02:42:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 16EF1222C2 for ; Wed, 13 Feb 2019 02:42:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550025720; bh=Nkk6Bi22Unzvml2E+EUGnmysxLz/qtg9Xpo6qA6xPFs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=XktPa/+50tVciL3IxkOBeErvh+plkNJNOoXKczJwYT1iuIOzpeSR0nPi2KN9JMClx tb2b+mgk35+SEo68+nkvZnJ5iPmujWli/XiDCCRpMnJMErpl021FSeXNGaDa3SrHUq tASr9F5NT7HrPeEKo2Vqm3zmyxDXXpKReSEsMaZA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387767AbfBMCl7 (ORCPT ); Tue, 12 Feb 2019 21:41:59 -0500 Received: from mail.kernel.org ([198.145.29.99]:45622 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389405AbfBMCl5 (ORCPT ); Tue, 12 Feb 2019 21:41:57 -0500 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 A4250222C2; Wed, 13 Feb 2019 02:41:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550025717; bh=Nkk6Bi22Unzvml2E+EUGnmysxLz/qtg9Xpo6qA6xPFs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XYWqDX4PRjsgI+o/wjjALxQNcSLb76C05rYvI3d3XGxMC71SRxJt/UsztO3dnoly6 GR6RGEZTcOOfgwhLn9QKbhn2rNdO78EOXJnQvVDl4o/E63vtpSHtFA6BpCBlwx0NHk lr0/FnKmrxtfTyiUFsPV9YLE8zHgp43XipScFX4E= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Colin Ian King , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 3.18 12/14] atm: he: fix sign-extension overflow on large shift Date: Tue, 12 Feb 2019 21:41:36 -0500 Message-Id: <20190213024139.22268-12-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190213024139.22268-1-sashal@kernel.org> References: <20190213024139.22268-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Colin Ian King [ Upstream commit cb12d72b27a6f41325ae23a11033cf5fedfa1b97 ] Shifting the 1 by exp by an int can lead to sign-extension overlow when exp is 31 since 1 is an signed int and sign-extending this result to an unsigned long long will set the upper 32 bits. Fix this by shifting an unsigned long. Detected by cppcheck: (warning) Shifting signed 32-bit value by 31 bits is undefined behaviour Signed-off-by: Colin Ian King Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/atm/he.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/atm/he.c b/drivers/atm/he.c index c39702bc279d..937f54ccbe6b 100644 --- a/drivers/atm/he.c +++ b/drivers/atm/he.c @@ -717,7 +717,7 @@ static int he_init_cs_block_rcm(struct he_dev *he_dev) instead of '/ 512', use '>> 9' to prevent a call to divdu3 on x86 platforms */ - rate_cps = (unsigned long long) (1 << exp) * (man + 512) >> 9; + rate_cps = (unsigned long long) (1UL << exp) * (man + 512) >> 9; if (rate_cps < 10) rate_cps = 10; /* 2.2.1 minimum payload rate is 10 cps */ -- 2.19.1