From nobody Thu Dec 26 12:39:16 2024 Delivered-To: importer@patchew.org Received-SPF: none (zoho.com: 198.145.21.10 is neither permitted nor denied by domain of lists.01.org) client-ip=198.145.21.10; envelope-from=edk2-devel-bounces@lists.01.org; helo=ml01.01.org; Authentication-Results: mx.zohomail.com; spf=none (zoho.com: 198.145.21.10 is neither permitted nor denied by domain of lists.01.org) smtp.mailfrom=edk2-devel-bounces@lists.01.org Return-Path: Received: from ml01.01.org (ml01.01.org [198.145.21.10]) by mx.zohomail.com with SMTPS id 150597639676393.37089867478824; Wed, 20 Sep 2017 23:46:36 -0700 (PDT) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 8ED2E21E1B751; Wed, 20 Sep 2017 23:43:23 -0700 (PDT) Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 6690C21E1B745 for ; Wed, 20 Sep 2017 23:43:22 -0700 (PDT) Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Sep 2017 23:46:29 -0700 Received: from shwdeopenpsi014.ccr.corp.intel.com ([10.239.9.13]) by fmsmga006.fm.intel.com with ESMTP; 20 Sep 2017 23:46:27 -0700 X-Original-To: edk2-devel@lists.01.org X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.42,424,1500966000"; d="scan'208";a="154331040" From: Hao Wu To: edk2-devel@lists.01.org Date: Thu, 21 Sep 2017 14:46:16 +0800 Message-Id: <20170921064617.2628-6-hao.a.wu@intel.com> X-Mailer: git-send-email 2.12.0.windows.1 In-Reply-To: <20170921064617.2628-1-hao.a.wu@intel.com> References: <20170921064617.2628-1-hao.a.wu@intel.com> Subject: [edk2] [PATCH v2 5/6] MdeModulePkg/Crc32: Fix possible out of range left shift X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Hao Wu , Paolo Bonzini , Eric Dong , Star Zeng MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Errors-To: edk2-devel-bounces@lists.01.org Sender: "edk2-devel" X-ZohoMail: RSF_4 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3D697 Within function ReverseBits(), left shift operations of 1 in the following statements: "(1 << Index)" and "(1 << (31 - Index))" will incur possible out of range left shift when Index is either 0 or 31, since "1 << 31" is possible to exceed the range of type 'int' (signed). According to the C11 spec, Section 6.5.7: > 4 The result of E1 << E2 is E1 left-shifted E2 bit positions; vacated > bits are filled with zeros. If E1 has an unsigned type, the value > of the result is E1 * 2^E2 , reduced modulo one more than the > maximum value representable in the result type. If E1 has a signed > type and nonnegative value, and E1 * 2^E2 is representable in the > result type, then that is the resulting value; otherwise, the > behavior is undefined. This commit uses '1U' instead of '1' to resolve this issue. Cc: Steven Shi Cc: Star Zeng Cc: Eric Dong Cc: Paolo Bonzini Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Hao Wu --- MdeModulePkg/Core/RuntimeDxe/Crc32.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/MdeModulePkg/Core/RuntimeDxe/Crc32.c b/MdeModulePkg/Core/Runti= meDxe/Crc32.c index a6fe77fa34..2cd234b562 100644 --- a/MdeModulePkg/Core/RuntimeDxe/Crc32.c +++ b/MdeModulePkg/Core/RuntimeDxe/Crc32.c @@ -7,7 +7,7 @@ EFI Runtime Services Table are converted from physical address to virtual addresses. This requires that the 32-bit CRC be recomputed. =20 -Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.
+Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.
This program and the accompanying materials are licensed and made available under the terms and conditions of the BSD = License which accompanies this distribution. The full text of the license may be = found at @@ -79,8 +79,8 @@ ReverseBits ( =20 NewValue =3D 0; for (Index =3D 0; Index < 32; Index++) { - if ((Value & (1 << Index)) !=3D 0) { - NewValue =3D NewValue | (1 << (31 - Index)); + if ((Value & (1U << Index)) !=3D 0) { + NewValue =3D NewValue | (1U << (31 - Index)); } } =20 --=20 2.12.0.windows.1 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel