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=-25.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, 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 3BF3AC63798 for ; Thu, 22 Jul 2021 16:34:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 265E76135C for ; Thu, 22 Jul 2021 16:34:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231179AbhGVPxr (ORCPT ); Thu, 22 Jul 2021 11:53:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:57190 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231175AbhGVPxd (ORCPT ); Thu, 22 Jul 2021 11:53:33 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 372876135A; Thu, 22 Jul 2021 16:34:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626971648; bh=RH22ivQk26BfVWl50jggGRFeZCgk9blc1Oyiox9KnlM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EGqdEQ3dGWqDf8hBa9LhVV0h5c3+L2sOPfEgjr5tZk8A6rZA0AYk363Q/fZJx89BT 9HVkYOcY+zjC5oWFTJjAKYd6zyU4gtDCf9Re2wkQWRv6pCPBqlJeo2D5mvQHHBvKiP pdfUND0a5hihdr4t78ckoaCNc4v/UDGQAMb9xCuk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Colin Ian King , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 5.4 38/71] scsi: aic7xxx: Fix unintentional sign extension issue on left shift of u8 Date: Thu, 22 Jul 2021 18:31:13 +0200 Message-Id: <20210722155619.132672037@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210722155617.865866034@linuxfoundation.org> References: <20210722155617.865866034@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: 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 4190a025381a..27d85ed82977 100644 --- a/drivers/scsi/aic7xxx/aic7xxx_core.c +++ b/drivers/scsi/aic7xxx/aic7xxx_core.c @@ -493,7 +493,7 @@ 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