From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 C27E121A00ACF for ; Fri, 23 Jun 2017 02:31:43 -0700 (PDT) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 23 Jun 2017 02:33:09 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.39,377,1493708400"; d="scan'208";a="102821357" Received: from fmsmsx106.amr.corp.intel.com ([10.18.124.204]) by orsmga002.jf.intel.com with ESMTP; 23 Jun 2017 02:33:08 -0700 Received: from fmsmsx117.amr.corp.intel.com (10.18.116.17) by FMSMSX106.amr.corp.intel.com (10.18.124.204) with Microsoft SMTP Server (TLS) id 14.3.319.2; Fri, 23 Jun 2017 02:33:08 -0700 Received: from shsmsx151.ccr.corp.intel.com (10.239.6.50) by fmsmsx117.amr.corp.intel.com (10.18.116.17) with Microsoft SMTP Server (TLS) id 14.3.319.2; Fri, 23 Jun 2017 02:33:08 -0700 Received: from shsmsx102.ccr.corp.intel.com ([169.254.2.146]) by SHSMSX151.ccr.corp.intel.com ([169.254.3.56]) with mapi id 14.03.0319.002; Fri, 23 Jun 2017 17:33:05 +0800 From: "Zeng, Star" To: "Ni, Ruiyu" , "edk2-devel@lists.01.org" CC: "Gao, Liming" , "Zeng, Star" Thread-Topic: [PATCH V2 3/3] DuetPkg FsVariable: Update GetNextVariableName to follow UEFI 2.7 Thread-Index: AQHS6/fkhgduWBrMm0+q6tMuxOxLcqIxlQAAgACYeJA= Date: Fri, 23 Jun 2017 09:33:04 +0000 Message-ID: <0C09AFA07DD0434D9E2A0C6AEB0483103B8ECCF8@shsmsx102.ccr.corp.intel.com> References: <1498205290-157888-1-git-send-email-star.zeng@intel.com> <1498205290-157888-4-git-send-email-star.zeng@intel.com> <734D49CCEBEEF84792F5B80ED585239D5B9A1821@SHSMSX104.ccr.corp.intel.com> In-Reply-To: <734D49CCEBEEF84792F5B80ED585239D5B9A1821@SHSMSX104.ccr.corp.intel.com> Accept-Language: zh-CN, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] MIME-Version: 1.0 Subject: Re: [PATCH V2 3/3] DuetPkg FsVariable: Update GetNextVariableName to follow UEFI 2.7 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: , X-List-Received-Date: Fri, 23 Jun 2017 09:31:44 -0000 Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Ray, It is to pass the check quickly and avoid scanning all the chars in Variabl= eName by StrnLenS for normal boot without invalid cases. I did experiments in the code of GetNextVariableName with below debug code = for normal boot on NT32 and my real platforms, all the cases will go into t= he branch "xxx 2". if (((VariableName[MaxLen - 1] !=3D 0))) { DEBUG ((DEBUG_INFO, "xxx 1\n")); } else { DEBUG ((DEBUG_INFO, "xxx 2\n")); } Thanks, Star -----Original Message----- From: Ni, Ruiyu=20 Sent: Friday, June 23, 2017 4:20 PM To: Zeng, Star ; edk2-devel@lists.01.org Cc: Gao, Liming Subject: RE: [PATCH V2 3/3] DuetPkg FsVariable: Update GetNextVariableName = to follow UEFI 2.7 Star, What's the benefit of this check "VariableName[MaxLen - 1] !=3D 0"? I think this check "StrnLenS (VariableName, MaxLen) =3D=3D MaxLen" should b= e enough. Thanks/Ray > -----Original Message----- > From: Zeng, Star > Sent: Friday, June 23, 2017 4:08 PM > To: edk2-devel@lists.01.org > Cc: Zeng, Star ; Gao, Liming ; > Ni, Ruiyu > Subject: [PATCH V2 3/3] DuetPkg FsVariable: Update GetNextVariableName > to follow UEFI 2.7 >=20 > "The size must be large enough to fit input string supplied in > VariableName buffer" is added in the description for VariableNameSize. > And two cases of EFI_INVALID_PARAMETER are added. > 1. The input values of VariableName and VendorGuid are not a name and > GUID of an existing variable. > 2. Null-terminator is not found in the first VariableNameSize bytes of > the input VariableName buffer. >=20 > This patch is to update code to follow them. >=20 > Cc: Liming Gao > Cc: Ruiyu Ni > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Star Zeng > --- > DuetPkg/FSVariable/FSVariable.c | 21 ++++++++++++++++++++- > 1 file changed, 20 insertions(+), 1 deletion(-) >=20 > diff --git a/DuetPkg/FSVariable/FSVariable.c > b/DuetPkg/FSVariable/FSVariable.c > index 34b79305c871..6069cfa8fb98 100644 > --- a/DuetPkg/FSVariable/FSVariable.c > +++ b/DuetPkg/FSVariable/FSVariable.c > @@ -6,7 +6,7 @@ disk. They can be changed by user. BIOS is not able to > protoect those. > Duet trusts all meta data from disk. If variable code, variable metadata= and > variable > data is modified in inproper way, the behavior is undefined. >=20 > -Copyright (c) 2006 - 2016, 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 BS= D > License > which accompanies this distribution. The full text of the license may b= e > found at > @@ -1400,14 +1400,33 @@ Returns: > VARIABLE_POINTER_TRACK Variable; > UINTN VarNameSize; > EFI_STATUS Status; > + UINTN MaxLen; >=20 > if (VariableNameSize =3D=3D NULL || VariableName =3D=3D NULL || Vendor= Guid =3D=3D > NULL) { > return EFI_INVALID_PARAMETER; > } >=20 > + // > + // Calculate the possible maximum length of name string, including the= Null > terminator. > + // > + MaxLen =3D *VariableNameSize / sizeof (CHAR16); > + if ((MaxLen =3D=3D 0) || > + ((VariableName[MaxLen - 1] !=3D 0) && (StrnLenS (VariableName, Max= Len) > =3D=3D MaxLen))) { > + // > + // Null-terminator is not found in the first VariableNameSize bytes = of the > input VariableName buffer. > + // > + return EFI_INVALID_PARAMETER; > + } > + > Status =3D FindVariable (VariableName, VendorGuid, &Variable); >=20 > if (Variable.CurrPtr =3D=3D NULL || EFI_ERROR (Status)) { > + if (VariableName[0] !=3D 0) { > + // > + // The input values of VariableName and VendorGuid are not a name > and GUID of an existing variable. > + // > + Status =3D EFI_INVALID_PARAMETER; > + } > return Status; > } >=20 > -- > 2.7.0.windows.1