From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=134.134.136.65; helo=mga03.intel.com; envelope-from=star.zeng@intel.com; receiver=edk2-devel@lists.01.org Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) (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 C89E721164F02 for ; Mon, 15 Oct 2018 19:41:04 -0700 (PDT) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Oct 2018 19:41:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,386,1534834800"; d="scan'208";a="81507198" Received: from shwdeopenpsi068.ccr.corp.intel.com ([10.239.158.46]) by orsmga007.jf.intel.com with ESMTP; 15 Oct 2018 19:41:02 -0700 From: Star Zeng To: edk2-devel@lists.01.org Cc: Star Zeng , Jiewen Yao , Chao Zhang , Jian J Wang Date: Tue, 16 Oct 2018 10:41:01 +0800 Message-Id: <1539657661-57656-1-git-send-email-star.zeng@intel.com> X-Mailer: git-send-email 2.7.0.windows.1 Subject: [PATCH] MdeModulePkg Variable: Fix Timestamp zeroing issue on APPEND_WRITE X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Oct 2018 02:41:06 -0000 REF: https://bugzilla.tianocore.org/show_bug.cgi?id=415 When SetVariable() to a time based auth variable with APPEND_WRITE attribute, and if the EFI_VARIABLE_AUTHENTICATION_2.TimeStamp in the input Data is earlier than current value, it will cause timestamp zeroing. This issue may bring time based auth variable downgrade problem. For example: A vendor released three certs at 2014, 2015, and 2016, and system integrated the 2016 cert. User can SetVariable() with 2015 cert and APPEND_WRITE attribute to cause timestamp zeroing first, then SetVariable() with 2014 cert to downgrade the cert. This patch fixes this issue. Cc: Jiewen Yao Cc: Chao Zhang Cc: Jian J Wang Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Star Zeng --- MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c index a2d61c8cd618..8e8db71bd201 100644 --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c @@ -2462,6 +2462,8 @@ UpdateVariable ( if (Variable->CurrPtr != NULL) { if (VariableCompareTimeStampInternal (&(((AUTHENTICATED_VARIABLE_HEADER *) CacheVariable->CurrPtr)->TimeStamp), TimeStamp)) { CopyMem (&AuthVariable->TimeStamp, TimeStamp, sizeof (EFI_TIME)); + } else { + CopyMem (&AuthVariable->TimeStamp, &(((AUTHENTICATED_VARIABLE_HEADER *) CacheVariable->CurrPtr)->TimeStamp), sizeof (EFI_TIME)); } } } -- 2.7.0.windows.1