From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (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 C2FF621A13482 for ; Thu, 4 May 2017 12:27:36 -0700 (PDT) Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1AD0C804E9; Thu, 4 May 2017 19:27:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 1AD0C804E9 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=lersek@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 1AD0C804E9 Received: from lacos-laptop-7.usersys.redhat.com (ovpn-116-56.phx2.redhat.com [10.3.116.56]) by smtp.corp.redhat.com (Postfix) with ESMTP id E44D37755E; Thu, 4 May 2017 19:27:34 +0000 (UTC) To: Jordan Justen , edk2-devel-01 References: <20170503213947.32290-1-lersek@redhat.com> <20170503213947.32290-5-lersek@redhat.com> <149391577010.7999.17667669342464390958@jljusten-skl.jf.intel.com> <795227c7-2191-239a-a940-4f5ea37adfc3@redhat.com> <149392380410.9783.3695261429662975796@jljusten-skl.jf.intel.com> Cc: Gary Ching-Pang Lin From: Laszlo Ersek Message-ID: Date: Thu, 4 May 2017 21:27:33 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <149392380410.9783.3695261429662975796@jljusten-skl.jf.intel.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Thu, 04 May 2017 19:27:36 +0000 (UTC) Subject: Re: [PATCH v2 4/5] OvmfPkg: raise max variable size (auth & non-auth) to 33KB for FD_SIZE_4MB 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: Thu, 04 May 2017 19:27:37 -0000 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit On 05/04/17 20:50, Jordan Justen wrote: > On 2017-05-04 09:52:48, Laszlo Ersek wrote: >> On 05/04/17 18:36, Jordan Justen wrote: >>> On 2017-05-03 14:39:46, Laszlo Ersek wrote: >>>> The "ConfirmSetOfLargeVariable" test case of the Secure Boot Logo Test >>>> ("Microsoft.UefiSecureBootLogo.Tests") suite in the Microsoft Hardware >>>> Certification Kit sets a 32 KB large non-authenticated variable. >>> >>> According to >>> http://www.uefi.org/sites/default/files/resources/UEFI_Plugfest_Security_Microsoft_Fall_2016.pdf >>> >>> "The maximum supported variable size must be at least 64kB" >>> >>> Should we just bump the size to match this? We should be able to make >>> this change later once it is in a test/spec, but for some reason I >>> thought the requirement was already 64k. >> >> The 32KB requirement comes from the most recent Secure Boot Logo Test. I > > If the limit is 32k, why go with 33k? Does the test fail with a 32k > limit? Yes, it does. First I tried setting the PCDs to 0x8000 sharp, and then the test failed. Then I remembered that the PCDs present a limit on data, name, and attributes together: (1) In "MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c", function InitNonVolatileVariableStore(), we stash the PCDs like this: > mVariableModuleGlobal->MaxVariableSize = PcdGet32 (PcdMaxVariableSize); > mVariableModuleGlobal->MaxAuthVariableSize = ((PcdGet32 (PcdMaxAuthVariableSize) != 0) ? PcdGet32 (PcdMaxAuthVariableSize) : mVariableModuleGlobal->MaxVariableSize); (2) In the same file, function VariableServiceSetVariable(), we have the following size checks: > // > // The size of the VariableName, including the Unicode Null in bytes plus > // the DataSize is limited to maximum size of PcdGet32 (PcdMaxHardwareErrorVariableSize) > // bytes for HwErrRec#### variable. > // > if ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == EFI_VARIABLE_HARDWARE_ERROR_RECORD) { > if (StrSize (VariableName) + PayloadSize > PcdGet32 (PcdMaxHardwareErrorVariableSize) - GetVariableHeaderSize ()) { > return EFI_INVALID_PARAMETER; > } > } else { > // > // The size of the VariableName, including the Unicode Null in bytes plus > // the DataSize is limited to maximum size of Max(Auth)VariableSize bytes. > // > if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) { > if (StrSize (VariableName) + PayloadSize > mVariableModuleGlobal->MaxAuthVariableSize - GetVariableHeaderSize ()) { > return EFI_INVALID_PARAMETER; > } > } else { > if (StrSize (VariableName) + PayloadSize > mVariableModuleGlobal->MaxVariableSize - GetVariableHeaderSize ()) { > return EFI_INVALID_PARAMETER; > } > } > } That is, the PCDs limit the sum of: - the variable name (including the terminating L'\0'), - the variable contents, - the internal header (which carries the attributes as well). In our case that's AUTHENTICATED_VARIABLE_HEADER, because we always format the auth varstore GUID into the template. Furthermore, the 32KB data size for the contents is not based on "reverse engineering"; the Secure Boot Logo Test tells you exactly what it is trying to do. (In fact, there is no other way to fix failures in any of the tests; you can only rely on the messages in order to see what the test attempted.) In this case, we have (see ): > NOTE: if this testcase fails, try restarting the machine and then > running this test case on its own, for example: "te.exe > UefiSecureBootLogo.dll > /name:Microsoft.UefiSecureBootLogo.Tests.ConfirmSetOfLargeVariable" > > Test creation of 1 large variable of size 32768 bytes. > > Test creation of testLargeVariable Unexpected Error - SetVariable > failed with status 0xC000000D VariableName "testLargeVariable" > VendorGuid 77fa9abd-0359-4d32-bd60-28f4e78f784b Attributes 0x00000007 > DataSize 0x00008000 It reports all the parameters of the gRT->SetVariable() call that failed, except "Data". In the successful test (with this patch applied), the messages are (see ): > NOTE: if this testcase fails, try restarting the machine and then > running this test case on its own, for example: "te.exe > UefiSecureBootLogo.dll > /name:Microsoft.UefiSecureBootLogo.Tests.ConfirmSetOfLargeVariable" > > Test creation of 1 large variable of size 32768 bytes. > > AreEqual(7, 7) - testLargeVariable: Attributes from GetVariable() > match SetVariable() > > AreEqual(32768, 32768) - testLargeVariable: DataSize from > GetVariable() matches SetVariable() Thanks Laszlo > >> installed both the Windows Server 2008 R2 SP1 test controller and the >> Windows 2016 Server test client just the other day, together with the >> most recent filters, using the following descriptions: >> >> https://msdn.microsoft.com/en-us/library/windows/hardware/jj123537.aspx >> https://github.com/daynix/VirtHCK/wiki#Checklist_for_a_New_Controller_VM >> https://github.com/daynix/VirtHCK/wiki#Checklist_for_a_New_Client_VM >> >> Given that this limit can be bumped without breaking compatibility, as >> you say, I'd like to remain frugal with it, same as we were in James's >> commit f5404a3eba1d ("OvmfPkg: Increase the maximum size for >> Authenticated variables", 2016-03-24). >> >> I don't understand why the plugfest presentation and the SB Logo Test >> require different limits... But, I'm certain our QE will find out in >> short order once the SB Logo Test catches up with the presentation, and >> I expect I'll submit the corresponding patch soon after. >> >> I dislike the speculation in this series, but breaking compatibility is >> even worse. (A lot worse, to me at least.) So I consider the varstore >> restructuring the smaller of two wrongs. However, wrt. >> PcdMaxVariableSize, it seems we're not being forced to either of those >> wrongs (i.e., breaking compat or speculation), so we can delay the increase. >> >>> >>> Aside from this question: >>> >>> Series Reviewed-by: Jordan Justen >> >> Thanks a lot! >> >> I'll await your ACK for the above argument before pushing the series. >> >> Thanks, >> Laszlo >> >>>> In the FD_SIZE_4MB build, our live varstore is now 256 KB big, so we can >>>> accommodate this. Set both PcdMaxVariableSize and PcdMaxAuthVariableSize >>>> to 0x8400 -- beyond DataSize=0x8000 from the HCK test, we need some room >>>> for the variable name and attributes as well. >>>> >>>> Cc: Gary Ching-Pang Lin >>>> Cc: Jordan Justen >>>> Contributed-under: TianoCore Contribution Agreement 1.0 >>>> Signed-off-by: Laszlo Ersek >>>> --- >>>> >>>> Notes: >>>> v2: >>>> - adjust to FD_SIZE_IN_KB >>>> - update commit msg to state 256 KB for the varstore [Jordan] >>>> >>>> OvmfPkg/OvmfPkgIa32.dsc | 6 ++++++ >>>> OvmfPkg/OvmfPkgIa32X64.dsc | 6 ++++++ >>>> OvmfPkg/OvmfPkgX64.dsc | 6 ++++++ >>>> 3 files changed, 18 insertions(+) >>>> >>>> diff --git a/OvmfPkg/OvmfPkgIa32.dsc b/OvmfPkg/OvmfPkgIa32.dsc >>>> index 26b807dde9fa..e0779ddaa426 100644 >>>> --- a/OvmfPkg/OvmfPkgIa32.dsc >>>> +++ b/OvmfPkg/OvmfPkgIa32.dsc >>>> @@ -404,28 +404,34 @@ [PcdsFeatureFlag] >>>> gUefiOvmfPkgTokenSpaceGuid.PcdSecureBootEnable|TRUE >>>> !endif >>>> !if $(SMM_REQUIRE) == TRUE >>>> gUefiOvmfPkgTokenSpaceGuid.PcdSmmSmramRequire|TRUE >>>> gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmEnableBspElection|FALSE >>>> !endif >>>> >>>> [PcdsFixedAtBuild] >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdStatusCodeMemorySize|1 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdResetOnMemoryTypeInformationChange|FALSE >>>> gEfiMdePkgTokenSpaceGuid.PcdMaximumGuidedExtractHandler|0x10 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxFvSupported|6 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxPeimPerFv|32 >>>> +!if ($(FD_SIZE_IN_KB) == 1024) || ($(FD_SIZE_IN_KB) == 2048) >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize|0x2000 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize|0x2800 >>>> +!endif >>>> +!if $(FD_SIZE_IN_KB) == 4096 >>>> + gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize|0x8400 >>>> + gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize|0x8400 >>>> +!endif >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdVariableStoreSize|0xe000 >>>> >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdVpdBaseAddress|0x0 >>>> >>>> gEfiMdePkgTokenSpaceGuid.PcdReportStatusCodePropertyMask|0x07 >>>> >>>> # DEBUG_INIT 0x00000001 // Initialization >>>> # DEBUG_WARN 0x00000002 // Warnings >>>> # DEBUG_LOAD 0x00000004 // Load events >>>> # DEBUG_FS 0x00000008 // EFI File system >>>> # DEBUG_POOL 0x00000010 // Alloc & Free (pool) >>>> # DEBUG_PAGE 0x00000020 // Alloc & Free (page) >>>> # DEBUG_INFO 0x00000040 // Informational debug messages >>>> diff --git a/OvmfPkg/OvmfPkgIa32X64.dsc b/OvmfPkg/OvmfPkgIa32X64.dsc >>>> index 41f06a6b6a66..bbe26e2cf452 100644 >>>> --- a/OvmfPkg/OvmfPkgIa32X64.dsc >>>> +++ b/OvmfPkg/OvmfPkgIa32X64.dsc >>>> @@ -409,28 +409,34 @@ [PcdsFeatureFlag] >>>> gUefiOvmfPkgTokenSpaceGuid.PcdSecureBootEnable|TRUE >>>> !endif >>>> !if $(SMM_REQUIRE) == TRUE >>>> gUefiOvmfPkgTokenSpaceGuid.PcdSmmSmramRequire|TRUE >>>> gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmEnableBspElection|FALSE >>>> !endif >>>> >>>> [PcdsFixedAtBuild] >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdStatusCodeMemorySize|1 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdResetOnMemoryTypeInformationChange|FALSE >>>> gEfiMdePkgTokenSpaceGuid.PcdMaximumGuidedExtractHandler|0x10 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxFvSupported|6 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxPeimPerFv|32 >>>> +!if ($(FD_SIZE_IN_KB) == 1024) || ($(FD_SIZE_IN_KB) == 2048) >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize|0x2000 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize|0x2800 >>>> +!endif >>>> +!if $(FD_SIZE_IN_KB) == 4096 >>>> + gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize|0x8400 >>>> + gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize|0x8400 >>>> +!endif >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdVariableStoreSize|0xe000 >>>> >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdVpdBaseAddress|0x0 >>>> >>>> gEfiMdePkgTokenSpaceGuid.PcdReportStatusCodePropertyMask|0x07 >>>> >>>> # DEBUG_INIT 0x00000001 // Initialization >>>> # DEBUG_WARN 0x00000002 // Warnings >>>> # DEBUG_LOAD 0x00000004 // Load events >>>> # DEBUG_FS 0x00000008 // EFI File system >>>> # DEBUG_POOL 0x00000010 // Alloc & Free (pool) >>>> # DEBUG_PAGE 0x00000020 // Alloc & Free (page) >>>> # DEBUG_INFO 0x00000040 // Informational debug messages >>>> diff --git a/OvmfPkg/OvmfPkgX64.dsc b/OvmfPkg/OvmfPkgX64.dsc >>>> index 053c84b685c5..ff795815f65f 100644 >>>> --- a/OvmfPkg/OvmfPkgX64.dsc >>>> +++ b/OvmfPkg/OvmfPkgX64.dsc >>>> @@ -409,28 +409,34 @@ [PcdsFeatureFlag] >>>> gUefiOvmfPkgTokenSpaceGuid.PcdSecureBootEnable|TRUE >>>> !endif >>>> !if $(SMM_REQUIRE) == TRUE >>>> gUefiOvmfPkgTokenSpaceGuid.PcdSmmSmramRequire|TRUE >>>> gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmEnableBspElection|FALSE >>>> !endif >>>> >>>> [PcdsFixedAtBuild] >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdStatusCodeMemorySize|1 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdResetOnMemoryTypeInformationChange|FALSE >>>> gEfiMdePkgTokenSpaceGuid.PcdMaximumGuidedExtractHandler|0x10 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxFvSupported|6 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdPeiCoreMaxPeimPerFv|32 >>>> +!if ($(FD_SIZE_IN_KB) == 1024) || ($(FD_SIZE_IN_KB) == 2048) >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize|0x2000 >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize|0x2800 >>>> +!endif >>>> +!if $(FD_SIZE_IN_KB) == 4096 >>>> + gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize|0x8400 >>>> + gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize|0x8400 >>>> +!endif >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdVariableStoreSize|0xe000 >>>> >>>> gEfiMdeModulePkgTokenSpaceGuid.PcdVpdBaseAddress|0x0 >>>> >>>> gEfiMdePkgTokenSpaceGuid.PcdReportStatusCodePropertyMask|0x07 >>>> >>>> # DEBUG_INIT 0x00000001 // Initialization >>>> # DEBUG_WARN 0x00000002 // Warnings >>>> # DEBUG_LOAD 0x00000004 // Load events >>>> # DEBUG_FS 0x00000008 // EFI File system >>>> # DEBUG_POOL 0x00000010 // Alloc & Free (pool) >>>> # DEBUG_PAGE 0x00000020 // Alloc & Free (page) >>>> # DEBUG_INFO 0x00000040 // Informational debug messages >>>> -- >>>> 2.9.3 >>>> >>>> >>