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authorHao Wu <hao.a.wu@intel.com>2017-09-19 16:11:29 +0800
committerHao Wu <hao.a.wu@intel.com>2017-09-29 16:14:17 +0800
commit27daa8658e518902bf281b07993c2d60af1913c3 (patch)
tree6d36cfd68d6cd6ef4d65c74ea507c6aaee1e1d19
parentbd42d976d510ab56e862b7bf764b1f9e9b19337e (diff)
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MdeModulePkg/AtaAtapiPassThru: Fix possible out of range left shift
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=699 Within function AhciModeInitialization(), left shift operations of 'BIT0' in the following statements: "if ((PortImplementBitMap & (BIT0 << Port)) != 0) {" will incur possible out of range left shift when Port is 31, since "1 << 31" is possible to exceed the range of type 'int' (signed). According to the C11 spec, Section 6.5.7: > 4 The result of E1 << E2 is E1 left-shifted E2 bit positions; vacated > bits are filled with zeros. If E1 has an unsigned type, the value > of the result is E1 * 2^E2 , reduced modulo one more than the > maximum value representable in the result type. If E1 has a signed > type and nonnegative value, and E1 * 2^E2 is representable in the > result type, then that is the resulting value; otherwise, the > behavior is undefined. This commit explicitly cast 'BIT0' with UINT32 to resolve this issue. Cc: Steven Shi <steven.shi@intel.com> Cc: Eric Dong <eric.dong@intel.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Hao Wu <hao.a.wu@intel.com> Reviewed-by: Star Zeng <star.zeng@intel.com>
-rw-r--r--MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
index b954de8..e6de5d6 100644
--- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
+++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
@@ -1,7 +1,7 @@
/** @file
The file for AHCI mode of ATA host controller.
- Copyright (c) 2010 - 2016, Intel Corporation. All rights reserved.<BR>
+ Copyright (c) 2010 - 2017, Intel Corporation. All rights reserved.<BR>
(C) Copyright 2015 Hewlett Packard Enterprise Development LP<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
@@ -2314,7 +2314,7 @@ AhciModeInitialization (
}
for (Port = 0; Port < EFI_AHCI_MAX_PORTS; Port ++) {
- if ((PortImplementBitMap & (BIT0 << Port)) != 0) {
+ if ((PortImplementBitMap & (((UINT32)BIT0) << Port)) != 0) {
//
// According to AHCI spec, MaxPortNumber should be equal or greater than the number of implemented ports.
//