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=-24.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,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 59AA0C49EBB for ; Wed, 14 Jul 2021 19:58:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43CB6613DC for ; Wed, 14 Jul 2021 19:58:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243807AbhGNUBU (ORCPT ); Wed, 14 Jul 2021 16:01:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:47272 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241189AbhGNTu0 (ORCPT ); Wed, 14 Jul 2021 15:50:26 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id BF54E613EC; Wed, 14 Jul 2021 19:47:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1626292035; bh=WbcAoORSEo3xrjNUt8TS+8PA0uazBmuXqcBbv3NVmi8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=O1De6OUQilspmAbLau4y8GG48K0Y4kw0fmpBrB83YvEWmkjQ8k1O69M5wsSdkWKe8 wFb4m3veWig2v/nYqxzVBWWoLCtkm85fXsZ0Mc0+P+H5iNWjTuYEnxok6dcEih3Ofd Am1DaxCiFV0zhiALLwMAETsIBDWQYrwhBAE6G3tHKw9uiNbYB5sZK6yV2q1xFaelOn CocNHxG/2Rm6Z+gyvnQKtCdMzTBhogU7KRhyvZo2RgopTDUpVKCf5omv7mmbLajqjK YiIYZ6vdoKjSDtQrWkd3qiGfyjbyLJHXjnCAT0uP9BnhILSbJ/O/WIr6KSKCeo+vqE ZrujY1P7GYH1A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Colin Ian King , "Martin K . Petersen" , Sasha Levin , linux-scsi@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 35/39] scsi: aic7xxx: Fix unintentional sign extension issue on left shift of u8 Date: Wed, 14 Jul 2021 15:46:20 -0400 Message-Id: <20210714194625.55303-35-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210714194625.55303-1-sashal@kernel.org> References: <20210714194625.55303-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Colin Ian King [ Upstream commit 332a9dd1d86f1e7203fc7f0fd7e82f0b304200fe ] The shifting of the u8 integer returned fom ahc_inb(ahc, port+3) by 24 bits to the left will be promoted to a 32 bit signed int and then sign-extended to a u64. In the event that the top bit of the u8 is set then all then all the upper 32 bits of the u64 end up as also being set because of the sign-extension. Fix this by casting the u8 values to a u64 before the 24 bit left shift. [ This dates back to 2002, I found the offending commit from the git history git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git, commit f58eb66c0b0a ("Update aic7xxx driver to 6.2.10...") ] Link: https://lore.kernel.org/r/20210621151727.20667-1-colin.king@canonical.com Signed-off-by: Colin Ian King Signed-off-by: Martin K. Petersen Addresses-Coverity: ("Unintended sign extension") Signed-off-by: Sasha Levin --- drivers/scsi/aic7xxx/aic7xxx_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/aic7xxx/aic7xxx_core.c b/drivers/scsi/aic7xxx/aic7xxx_core.c index 49e02e874553..fe15746af520 100644 --- a/drivers/scsi/aic7xxx/aic7xxx_core.c +++ b/drivers/scsi/aic7xxx/aic7xxx_core.c @@ -500,7 +500,7 @@ ahc_inq(struct ahc_softc *ahc, u_int port) return ((ahc_inb(ahc, port)) | (ahc_inb(ahc, port+1) << 8) | (ahc_inb(ahc, port+2) << 16) - | (ahc_inb(ahc, port+3) << 24) + | (((uint64_t)ahc_inb(ahc, port+3)) << 24) | (((uint64_t)ahc_inb(ahc, port+4)) << 32) | (((uint64_t)ahc_inb(ahc, port+5)) << 40) | (((uint64_t)ahc_inb(ahc, port+6)) << 48) -- 2.30.2