From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=192.55.52.43; helo=mga05.intel.com; envelope-from=jian.j.wang@intel.com; receiver=edk2-devel@lists.01.org Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) (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 BFFA02202E48A for ; Wed, 14 Mar 2018 21:57:09 -0700 (PDT) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Mar 2018 22:03:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.48,308,1517904000"; d="scan'208";a="39044990" Received: from jwang36-mobl2.ccr.corp.intel.com ([10.239.192.71]) by orsmga001.jf.intel.com with ESMTP; 14 Mar 2018 22:03:32 -0700 From: Jian J Wang To: edk2-devel@lists.01.org Cc: Star Zeng , Eric Dong , Jiewen Yao , Ruiyu Ni Date: Thu, 15 Mar 2018 13:03:26 +0800 Message-Id: <20180315050326.17440-4-jian.j.wang@intel.com> X-Mailer: git-send-email 2.15.1.windows.2 In-Reply-To: <20180315050326.17440-1-jian.j.wang@intel.com> References: <20180315050326.17440-1-jian.j.wang@intel.com> Subject: [PATCH v3 3/3] MdeModulePkg/Core: fix bits operation error on a boundary condition X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 15 Mar 2018 04:57:10 -0000 If given address is on 64K boundary and the requested bit number is 64, all SetBits(), ClearBits() and GetBits() will encounter ASSERT problem in trying to do a 64 bits of shift, which is not allowed by LShift() and RShift(). This patch tries to fix this issue by turning bits operation into whole integer operation in such situation. Cc: Star Zeng Cc: Eric Dong Cc: Jiewen Yao Cc: Ruiyu Ni Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Jian J Wang --- MdeModulePkg/Core/Dxe/Mem/HeapGuard.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c b/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c index f6068c459c..fd6aeee8da 100644 --- a/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c +++ b/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c @@ -70,7 +70,7 @@ SetBits ( StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address); EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS; - if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) { + if ((StartBit + BitNumber) >= GUARDED_HEAP_MAP_ENTRY_BITS) { Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) % GUARDED_HEAP_MAP_ENTRY_BITS; Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS; @@ -123,7 +123,7 @@ ClearBits ( StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address); EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS; - if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) { + if ((StartBit + BitNumber) >= GUARDED_HEAP_MAP_ENTRY_BITS) { Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) % GUARDED_HEAP_MAP_ENTRY_BITS; Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS; @@ -188,10 +188,14 @@ GetBits ( Lsbs = 0; } - Result = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1); - if (Lsbs > 0) { - BitMap += 1; - Result |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs); + if (StartBit == 0 && BitNumber == GUARDED_HEAP_MAP_ENTRY_BITS) { + Result = *BitMap; + } else { + Result = RShiftU64((*BitMap), StartBit) & (LShiftU64(1, Msbs) - 1); + if (Lsbs > 0) { + BitMap += 1; + Result |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs); + } } return Result; -- 2.16.2.windows.1