From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=2607:f8b0:4001:c0b::242; helo=mail-it0-x242.google.com; envelope-from=ard.biesheuvel@linaro.org; receiver=edk2-devel@lists.01.org Received: from mail-it0-x242.google.com (mail-it0-x242.google.com [IPv6:2607:f8b0:4001:c0b::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id B0CA0211F8876 for ; Wed, 11 Jul 2018 07:16:32 -0700 (PDT) Received: by mail-it0-x242.google.com with SMTP id s7-v6so3791270itb.4 for ; Wed, 11 Jul 2018 07:16:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=TbJY9rs9ylx0Py9HgZZpDDCHbAf3wbiJYAhRZY5Agdo=; b=ktzIcgEHeMxjtUKqCU7CK0YwO5lrSYEW7u7GWbnS0rPqmDa1TLcLSC1VCW5ir3lP2x 7UVkGw9vsP6DC08rAu4mG7nTH/zWaOosii2ghmLkuMo0ZiQzn2kCTM12ceTeOC+1wikw jm4g95GnHS05GVhM1aaRxonzzdELx9IXPXNPg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=TbJY9rs9ylx0Py9HgZZpDDCHbAf3wbiJYAhRZY5Agdo=; b=cSDFFDCz/si+E4HNbQq7XXlBCu7lhT08Ioa3WTQIr2QhR6tattaq/KSW3V+6o7WBQI b9j2HzUOoufVrXKFWcXlYXhwTZJRRn1pc/PNvVOGn1Ad4aXLewPZ2HpO5khKcL6rJPgW 5zzO3dgDsY2PK624uP2yLuxSjaznO6gMwvhix3pmZ8axpqfJRjvbKgL11RG6FRMX5V+b r5z1L9hs9BxvFXZtyOgMg9xW+fVBOSM/CCfkbmZZZxoj34OoDZUvmcOF92VLDGUyEF2v v9pzNZTQC1Y1Ini1SuaOAQvUVmw30ZwMofKu++mc2EE1I+4/e9bYVYzx/kthdl6+jMil S2ZQ== X-Gm-Message-State: APt69E0/GaJyWXqAPzA9wQkOLboDlHqsz7jPt2TngXczUuK4gIeePs6e FBJ2GDLNQXChc9i7ONEbbUFHaiv8GbUCOVlFOlIdGA== X-Google-Smtp-Source: AAOMgpehmXXzsur+vsx8i39YwOQkm0FRf+Y4RHgVAnWLZlmtSiR7rYk7/iowOWXQb2+q+4AGsHskPNhUx5UAx4TJdHM= X-Received: by 2002:a02:35a:: with SMTP id y87-v6mr24794671jad.2.1531318591406; Wed, 11 Jul 2018 07:16:31 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a6b:bbc7:0:0:0:0:0 with HTTP; Wed, 11 Jul 2018 07:16:30 -0700 (PDT) In-Reply-To: <5bca3f43-7c23-dca6-03cd-2d647d8fe253@redhat.com> References: <20180710225105.28443-1-roman.bacik@broadcom.com> <5bca3f43-7c23-dca6-03cd-2d647d8fe253@redhat.com> From: Ard Biesheuvel Date: Wed, 11 Jul 2018 16:16:30 +0200 Message-ID: To: Laszlo Ersek Cc: rbacik@gmail.com, "edk2-devel@lists.01.org" , Jiewen Yao , Vladimir Olovyannikov , Chao Zhang , "Jordan Justen (Intel address)" , Michael Kinney , "Gao, Liming" Subject: Re: [PATCH v2] SecurityPkg: Fix assert when setting key from eMMC/SD/USB X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 11 Jul 2018 14:16:32 -0000 Content-Type: text/plain; charset="UTF-8" On 11 July 2018 at 14:05, Laszlo Ersek wrote: > Hi Roman, > > On 07/11/18 00:51, rbacik@gmail.com wrote: >> From: Roman Bacik >> >> When secure boot is enabled, if one loads keys from a FAT formatted >> eMMC/SD/USB when trying to provision PK/KEK/DB keys via the menu, >> an assert in StrLen() occurs. >> This is because the filename starts on odd address, which is not a uint16 >> aligned boundary: https://bugzilla.tianocore.org/show_bug.cgi?id=1003 >> >> Cc: Chao Zhang >> Cc: Jiewen Yao >> Cc: Laszlo Ersek >> Cc: Vladimir Olovyannikov >> Contributed-under: TianoCore Contribution Agreement 1.1 >> Signed-off-by: Roman Bacik >> --- >> SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c | 13 +++++++++++-- >> 1 file changed, 11 insertions(+), 2 deletions(-) > > Thank you for sending a well-formed patch. > > I notice that you sent this email from , which is not > the same as the Signed-off-by line. I realize you posted from > for technical reasons, and it should be no problem. > > However, I *think* in such cases we usually request the following: > > - Using your broadcom.com email address, please respond to this patch > (not my present email, but your original git posting), keeping full > context, and just repeat your Signed-off-by line (referencing the > broadcom address). > > I'm CC'ing Jordan and Ard for confirmation -- I believe this is what > we've done in the past, in cases when submitters had to post their work > from private addresses due to company email issues. > Yes, please. > Technical comments below: > >> diff --git a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c >> index 1b6f88804275..19b13a5569a6 100644 >> --- a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c >> +++ b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c >> @@ -123,6 +123,8 @@ OpenFileByDevicePath( >> EFI_FILE_PROTOCOL *Handle1; >> EFI_FILE_PROTOCOL *Handle2; >> EFI_HANDLE DeviceHandle; >> + CHAR16 *PathName; >> + UINTN PathLength; >> >> if ((FilePath == NULL || FileHandle == NULL)) { >> return EFI_INVALID_PARAMETER; >> @@ -173,6 +175,11 @@ OpenFileByDevicePath( >> // >> Handle2 = Handle1; >> Handle1 = NULL; >> + PathLength = DevicePathNodeLength(*FilePath) - sizeof(EFI_DEVICE_PATH_PROTOCOL); >> + PathName = AllocateCopyPool(PathLength, ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName); > > (1) On both lines above, space characters are missing after: > DevicePathNodeLength, sizeof, and AllocateCopyPool. (Edk2 coding style.) > I think we can fix this up for you when we push the patch. (I'm willing > to help with that, but we need SecurityPkg maintainer review first.) > > >> + if (PathName == NULL) { >> + return EFI_OUT_OF_RESOURCES; >> + } > > (2) I have now reviewed the original state of the function more > carefully, and, while the above "return" branch introduces a leak > *path*, it does not introduce a leak that doesn't already exist! > > In fact, the original function has multiple issues: > > - If the OpenVolume() call fails, "FileHandle" is set to NULL. That's > useless; the intent is obviously to set (*FileHandle) to NULL. > > - At the top of the "while" loop body, "Handle1" stands for an open > EFI_FILE_PROTOCOL. If the device path type check at the top of the loop > body returns EFI_INVALID_PARAMETER, then it (a) performs the same > useless assignment to "FileHandle" as described above, and (b) fails to > close "Handle1". This is why I say that the above EFI_OUT_OF_RESOURCES > branch introduces no new leak, just a new path to the existent leak. > > - The OpenFileByDevicePath() function is duplicated in the following > modules: "NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigImpl.c", and > "MdeModulePkg/Universal/Disk/RamDiskDxe/RamDiskFileExplorer.c". With the > implication that the alignment issue you found affects all three drivers! > > > Roman, I realize this could be more than what you signed up for; so > please pick one: > > (2a) you could submit a patch series: > > * Write a patch that sets (*FilePath) to NULL right after the > (FileHandle==NULL) check, in preparation for failure, and removes all > the bogus FileHandle=NULL assignments. > > * Write another patch that plugs the leak when the device path type > check fails -- introduce a "CloseHandle1" label at the end of the > function, and jump to it when the devpath type check fails, so that we > close "Handle1". This patch should also invert the meanings of Handle2 > and Handle1 -- the reassignment to Handle1 should only occur *after* we > successfully open Handle2. "Handle1" should *always* remain suitable for > closing through the "CloseHandle1" error path. > > * Include your current patch, for fixing the alignment issue. > > * Write another patch that moves the OpenFileByDevicePath() function to > UefiLib in MdePkg -- under the name EfiOpenFileByDevicePath() -- from > SecureBootConfigDxe. > > * write two more patches, namely for TlsAuthConfigDxe and RamDiskDxe, in > order to consume EfiOpenFileByDevicePath() from UefiLib. Both of those > modules already depend on UefiLib. > > (2b) Alternatively: > > * we can report a new TianoCore BZ about the issues I list above, > > * we can commit this patch of yours as-is, just additionally reference > the *new* BZ in the commit message, as "further known issues", > > * I can work on the rest of the issues. > > > If you pick (2b), then I can > - file the new BZ, > - update the commit message for you, > - update the patch for you, as described in (1), > - ACK this patch (as updated above), > - push the patch (if SecurityPkg maintainers agree), > - take on the new BZ as well. > > Thanks! > Laszlo > >> >> // >> // Try to test opening an existing file >> @@ -180,7 +187,7 @@ OpenFileByDevicePath( >> Status = Handle2->Open ( >> Handle2, >> &Handle1, >> - ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName, >> + PathName, >> OpenMode &~EFI_FILE_MODE_CREATE, >> 0 >> ); >> @@ -192,7 +199,7 @@ OpenFileByDevicePath( >> Status = Handle2->Open ( >> Handle2, >> &Handle1, >> - ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName, >> + PathName, >> OpenMode, >> Attributes >> ); >> @@ -202,6 +209,8 @@ OpenFileByDevicePath( >> // >> Handle2->Close (Handle2); >> >> + FreePool (PathName); >> + >> if (EFI_ERROR(Status)) { >> return (Status); >> } >> >