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....@intel.com>
Cc: Star Zeng <star.z...@intel.com>
Cc: Eric Dong <eric.d...@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a...@intel.com>
---
MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
index b954de8101..e6de5d65bc 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.
//
--
2.12.0.windows.1
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