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 827B02095A6A1 for ; Sun, 25 Jun 2017 23:16:57 -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; 25 Jun 2017 23:18:26 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.39,394,1493708400"; d="scan'208";a="119223210" Received: from fmsmsx103.amr.corp.intel.com ([10.18.124.201]) by fmsmga006.fm.intel.com with ESMTP; 25 Jun 2017 23:18:24 -0700 Received: from fmsmsx126.amr.corp.intel.com (10.18.125.43) by FMSMSX103.amr.corp.intel.com (10.18.124.201) with Microsoft SMTP Server (TLS) id 14.3.319.2; Sun, 25 Jun 2017 23:18:24 -0700 Received: from shsmsx101.ccr.corp.intel.com (10.239.4.153) by FMSMSX126.amr.corp.intel.com (10.18.125.43) with Microsoft SMTP Server (TLS) id 14.3.319.2; Sun, 25 Jun 2017 23:18:23 -0700 Received: from shsmsx104.ccr.corp.intel.com ([169.254.5.151]) by SHSMSX101.ccr.corp.intel.com ([169.254.1.197]) with mapi id 14.03.0319.002; Mon, 26 Jun 2017 14:18:21 +0800 From: "Ni, Ruiyu" To: "Zeng, Star" , "edk2-devel@lists.01.org" CC: "Gao, Liming" Thread-Topic: [PATCH V2 3/3] DuetPkg FsVariable: Update GetNextVariableName to follow UEFI 2.7 Thread-Index: AQHS6/fktIGxIeitq0WddwzRuQXyn6IyGjwA//+PJQCAAZolsIACsFcAgACuoGD//30jAIAAhz+Q//971YAAEaMB8A== Date: Mon, 26 Jun 2017 06:18:21 +0000 Message-ID: <734D49CCEBEEF84792F5B80ED585239D5B9A46BB@SHSMSX104.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> <0C09AFA07DD0434D9E2A0C6AEB0483103B8ECCF8@shsmsx102.ccr.corp.intel.com> <734D49CCEBEEF84792F5B80ED585239D5B9A239D@SHSMSX104.ccr.corp.intel.com> <0C09AFA07DD0434D9E2A0C6AEB0483103B8ED350@shsmsx102.ccr.corp.intel.com> <734D49CCEBEEF84792F5B80ED585239D5B9A458B@SHSMSX104.ccr.corp.intel.com> <0C09AFA07DD0434D9E2A0C6AEB0483103B8ED40B@shsmsx102.ccr.corp.intel.com> <734D49CCEBEEF84792F5B80ED585239D5B9A462B@SHSMSX104.ccr.corp.intel.com> <0C09AFA07DD0434D9E2A0C6AEB0483103B8ED461@shsmsx102.ccr.corp.intel.com> In-Reply-To: <0C09AFA07DD0434D9E2A0C6AEB0483103B8ED461@shsmsx102.ccr.corp.intel.com> Accept-Language: en-US, zh-CN 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: Mon, 26 Jun 2017 06:16:57 -0000 Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Thanks! Could you please put the comments in code? But why do you say it's unpredictable? The behavior is to return EFI_NOT_FO= UND. Thanks/Ray > -----Original Message----- > From: Zeng, Star > Sent: Monday, June 26, 2017 1:52 PM > To: Ni, Ruiyu ; edk2-devel@lists.01.org > Cc: Gao, Liming ; Zeng, Star > Subject: RE: [PATCH V2 3/3] DuetPkg FsVariable: Update > GetNextVariableName to follow UEFI 2.7 >=20 > Before UEFI 2.6a and 2.7, the behavior is unpredictable, our *CODE* chose= to > return EFI_NOT_FOUND. >=20 > "Passing in a VariableName parameter that is neither a Null-terminated st= ring > nor a value that was returned on the previous call to > GetNextVariableName() may also produce unpredictable results." >=20 >=20 >=20 > Thanks, > Star > -----Original Message----- > From: Ni, Ruiyu > Sent: Monday, June 26, 2017 1:47 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 >=20 > Can you add more comments here to describe the purpose is to change the > return status from Not Found to Invalid Parameter, and the reason of > choosing Invalid Parameter? >=20 > Thanks/Ray >=20 > > -----Original Message----- > > From: Zeng, Star > > Sent: Monday, June 26, 2017 1:41 PM > > To: Ni, Ruiyu ; edk2-devel@lists.01.org > > Cc: Gao, Liming ; Zeng, Star > > > > Subject: RE: [PATCH V2 3/3] DuetPkg FsVariable: Update > > GetNextVariableName to follow UEFI 2.7 > > > > It is to return EFI_INVALID_PARAMETER when the input VariableName and > > VendorGuid are not a valid variable to search next variable. > > It is added from UEFI 2.7 spec. > > Before the spec change, the code is to return EFI_NOT_FOUND at that cas= e. > > After the spec change, EFI_NOT_FOUND seemingly is reserved to indicate > > the ending of searching. > > > > > > Thanks, > > Star > > -----Original Message----- > > From: Ni, Ruiyu > > Sent: Monday, June 26, 2017 1:37 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 > > > > I understand your point. > > But I do think it hurts readability. > > > > BTW, what does the below change does? > > 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; > > } > > > > > > Thanks/Ray > > > > > -----Original Message----- > > > From: Zeng, Star > > > Sent: Monday, June 26, 2017 11:05 AM > > > To: Ni, Ruiyu ; edk2-devel@lists.01.org > > > Cc: Gao, Liming ; Zeng, Star > > > > > > Subject: RE: [PATCH V2 3/3] DuetPkg FsVariable: Update > > > GetNextVariableName to follow UEFI 2.7 > > > > > > Ray, > > > > > > The code is like low hanging fruit from my practice for me, and I > > > don't think it hurts readability although it may not bring > > > performance improvement, it depends on how many variables in > > > variable region, how many times of calling GetNextVariableName, and > > > how fast of > > GetNextVariableName. > > > > > > The code practice I did is on NT32 and my real platforms. Is there > > > anyone can make sure he/she tested all the systems in the world for > > > their > > code? > > > > > > > > > Anyway, I can update the patch if you insist. > > > > > > > > > Thanks, > > > Star > > > -----Original Message----- > > > From: Ni, Ruiyu > > > Sent: Saturday, June 24, 2017 10:08 AM > > > 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, > > > I don't recommend to add the additional check for performance > > > consideration. > > > Because we have no idea what the input VariableName buffer is like. > > > If the VariableName is like ['\0', '?', '?', '?'] with MaxLen equals > > > to 4, "VariableName[MaxLen-1] !=3D 0" check is redundant. > > > The NT32 case you met cannot represent the all possible cases. > > > You could use the possibility theory to decide what the most > > > efficient way > > is. > > > > > > Additionally I think code readability is more important than efficien= cy. > > > In this case, we need the data about the performance improvement to > > > decide whether this check is necessary. > > > > > > > > > Regards, > > > Ray > > > > > > >-----Original Message----- > > > >From: Zeng, Star > > > >Sent: Friday, June 23, 2017 5:33 PM > > > >To: Ni, Ruiyu ; edk2-devel@lists.01.org > > > >Cc: Gao, Liming ; Zeng, Star > > > > > > > >Subject: RE: [PATCH V2 3/3] DuetPkg FsVariable: Update > > > >GetNextVariableName to follow UEFI 2.7 > > > > > > > >Ray, > > > > > > > >It is to pass the check quickly and avoid scanning all the chars in > > > >VariableName 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 the 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 > > > >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 be > > > 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 > > > >> > > > >> "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 byte= s of > > > >> the input VariableName buffer. > > > >> > > > >> This patch is to update code to follow them. > > > >> > > > >> 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(-) > > > >> > > > >> 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. > > > >> > > > >> -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 BSD License > > > >> which accompanies this distribution. The full text of the > > > >> license may be found at @@ -1400,14 +1400,33 @@ Returns: > > > >> VARIABLE_POINTER_TRACK Variable; > > > >> UINTN VarNameSize; > > > >> EFI_STATUS Status; > > > >> + UINTN MaxLen; > > > >> > > > >> if (VariableNameSize =3D=3D NULL || VariableName =3D=3D NULL || > > > >> VendorGuid =3D=3D > > > >> NULL) { > > > >> return EFI_INVALID_PARAMETER; > > > >> } > > > >> > > > >> + // > > > >> + // 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, > > > >> + MaxLen) > > > >> =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); > > > >> > > > >> 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; > > > >> } > > > >> > > > >> -- > > > >> 2.7.0.windows.1