* [PATCH v2 0/6] Refine type cast for pointer subtraction
@ 2017-01-25 5:28 Hao Wu
2017-01-25 5:28 ` [PATCH v2 1/6] MdeModulePkg: " Hao Wu
2017-01-25 5:36 ` [PATCH v2 0/6] " Laszlo Ersek
0 siblings, 2 replies; 3+ messages in thread
From: Hao Wu @ 2017-01-25 5:28 UTC (permalink / raw)
To: edk2-devel; +Cc: Hao Wu, Laszlo Ersek
Please note that this patch is maily for feedback collection and only the
MdeModulePkg part of the series is sent out firstly.
V2 refines the commit messages:
For pointer subtraction, the result is of type "ptrdiff_t". According to
the C11 standard (Committee Draft - April 12, 2011):
"When two pointers are subtracted, both shall point to elements of the
same array object, or one past the last element of the array object; the
result is the difference of the subscripts of the two array elements. The
size of the result is implementation-defined, and its type (a signed
integer type) is ptrdiff_t defined in the <stddef.h> header. If the result
is not representable in an object of that type, the behavior is
undefined."
In our codes, there are cases that the pointer subtraction is not
performed by pointers to elements of the same array object. This might
lead to potential issues, since the behavior is undefined according to C11
standard.
Also, since the size of type "ptrdiff_t" is implementation-defined. Some
static code checkers may warn that the pointer subtraction might underflow
first and then being cast to a bigger size. For example:
UINT8 *Ptr1, *Ptr2;
UINTN PtrDiff;
...
PtrDiff = (UINTN) (Ptr1 - Ptr2);
The commit will refine the pointer subtraction expressions by casting each
pointer to UINTN first and then perform the subtraction:
PtrDiff = (UINTN) Ptr1 - (UINTN) Ptr2;
V1:
For pointer subtraction, the result is of type "ptrdiff_t". According to
the C11 spec, ptrdiff_t is a signed integer type but its size is
implementation-defined.
There are cases that the result of pointer subtraction is type casted to
UINTN, like:
UINT8 *Ptr1, *Ptr2;
UINTN PtrDiff;
...
PtrDiff = (UINTN) (Ptr1 - Ptr2);
Some static code checkers may warn that the pointer subtraction might
overflow first and then the result is being cast to a bigger size.
The series will cast each pointer to UINTN first and then perform the
subtraction:
PtrDiff = (UINTN) Ptr1 - (UINTN) Ptr2;
Cc: Laszlo Ersek <lersek@redhat.com>
Hao Wu (6):
MdeModulePkg: Refine type cast for pointer subtraction
CryptoPkg: Refine type cast for pointer subtraction
IntelFrameworkModulePkg: Refine type cast for pointer subtraction
NetworkPkg: Refine type cast for pointer subtraction
SecurityPkg: Refine type cast for pointer subtraction
ShellPkg: Refine type cast for pointer subtraction
CryptoPkg/Library/BaseCryptLib/SysCall/RuntimeMemAllocation.c | 6 +++---
IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyPci.c | 4 ++--
IntelFrameworkModulePkg/Library/GenericBdsLib/BdsBoot.c | 4 ++--
IntelFrameworkModulePkg/Library/GenericBdsLib/BdsConsole.c | 4 ++--
IntelFrameworkModulePkg/Library/GenericBdsLib/BdsMisc.c | 4 ++--
IntelFrameworkModulePkg/Library/LegacyBootManagerLib/LegacyBm.c | 4 ++--
IntelFrameworkModulePkg/Universal/BdsDxe/BootMaint/BootOption.c | 6 +++---
MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c | 4 ++--
MdeModulePkg/Include/Library/NetLib.h | 6 +++---
MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleLib.c | 4 ++--
MdeModulePkg/Library/DxePrintLibPrint2Protocol/PrintLib.c | 2 +-
MdeModulePkg/Library/FileExplorerLib/FileExplorer.c | 6 +++---
MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c | 4 ++--
MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c | 4 ++--
MdeModulePkg/Universal/DebugPortDxe/DebugPort.c | 4 ++--
MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c | 4 ++--
MdeModulePkg/Universal/HiiDatabaseDxe/Image.c | 4 ++--
MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c | 10 +++++-----
NetworkPkg/HttpDxe/HttpImpl.c | 6 +++---
SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c | 18 +++++++++---------
SecurityPkg/Library/DxeTpmMeasureBootLib/DxeTpmMeasureBootLib.c | 10 +++++-----
SecurityPkg/Library/Tpm2CommandLib/Tpm2Help.c | 6 +++---
SecurityPkg/Tcg/Tcg2Dxe/MeasureBootPeCoff.c | 10 +++++-----
SecurityPkg/Tcg/TrEEDxe/MeasureBootPeCoff.c | 10 +++++-----
SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c | 14 +++++++-------
ShellPkg/Application/Shell/ShellParametersProtocol.c | 6 +++---
ShellPkg/Library/UefiShellDebug1CommandsLib/DmpStore.c | 4 ++--
ShellPkg/Library/UefiShellDebug1CommandsLib/SmbiosView/SmbiosView.c | 4 ++--
ShellPkg/Library/UefiShellDriver1CommandsLib/Dh.c | 4 ++--
ShellPkg/Library/UefiShellLevel2CommandsLib/Cd.c | 6 +++---
30 files changed, 91 insertions(+), 91 deletions(-)
--
1.9.5.msysgit.0
^ permalink raw reply [flat|nested] 3+ messages in thread
* [PATCH v2 1/6] MdeModulePkg: Refine type cast for pointer subtraction
2017-01-25 5:28 [PATCH v2 0/6] Refine type cast for pointer subtraction Hao Wu
@ 2017-01-25 5:28 ` Hao Wu
2017-01-25 5:36 ` [PATCH v2 0/6] " Laszlo Ersek
1 sibling, 0 replies; 3+ messages in thread
From: Hao Wu @ 2017-01-25 5:28 UTC (permalink / raw)
To: edk2-devel; +Cc: Hao Wu
For pointer subtraction, the result is of type "ptrdiff_t". According to
the C11 standard (Committee Draft - April 12, 2011):
"When two pointers are subtracted, both shall point to elements of the
same array object, or one past the last element of the array object; the
result is the difference of the subscripts of the two array elements. The
size of the result is implementation-defined, and its type (a signed
integer type) is ptrdiff_t defined in the <stddef.h> header. If the result
is not representable in an object of that type, the behavior is
undefined."
In our codes, there are cases that the pointer subtraction is not
performed by pointers to elements of the same array object. This might
lead to potential issues, since the behavior is undefined according to C11
standard.
Also, since the size of type "ptrdiff_t" is implementation-defined. Some
static code checkers may warn that the pointer subtraction might underflow
first and then being cast to a bigger size. For example:
UINT8 *Ptr1, *Ptr2;
UINTN PtrDiff;
...
PtrDiff = (UINTN) (Ptr1 - Ptr2);
The commit will refine the pointer subtraction expressions by casting each
pointer to UINTN first and then perform the subtraction:
PtrDiff = (UINTN) Ptr1 - (UINTN) Ptr2;
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
---
MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c | 4 ++--
MdeModulePkg/Include/Library/NetLib.h | 6 +++---
MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleLib.c | 4 ++--
MdeModulePkg/Library/DxePrintLibPrint2Protocol/PrintLib.c | 2 +-
MdeModulePkg/Library/FileExplorerLib/FileExplorer.c | 6 +++---
MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c | 4 ++--
MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c | 4 ++--
MdeModulePkg/Universal/DebugPortDxe/DebugPort.c | 4 ++--
MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c | 4 ++--
MdeModulePkg/Universal/HiiDatabaseDxe/Image.c | 4 ++--
MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c | 10 +++++-----
11 files changed, 26 insertions(+), 26 deletions(-)
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
index 2bc4f8c..d2ad94e 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
@@ -1,7 +1,7 @@
/** @file
PCI Rom supporting funtions implementation for PCI Bus module.
-Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -776,7 +776,7 @@ ProcessOpRomImage (
NextImage:
RomBarOffset += ImageSize;
- } while (((Indicator & 0x80) == 0x00) && ((UINTN) (RomBarOffset - (UINT8 *) RomBar) < PciDevice->RomSize));
+ } while (((Indicator & 0x80) == 0x00) && (((UINTN) RomBarOffset - (UINTN) RomBar) < PciDevice->RomSize));
return RetStatus;
}
diff --git a/MdeModulePkg/Include/Library/NetLib.h b/MdeModulePkg/Include/Library/NetLib.h
index 09ead09..3b8ff1a 100644
--- a/MdeModulePkg/Include/Library/NetLib.h
+++ b/MdeModulePkg/Include/Library/NetLib.h
@@ -2,7 +2,7 @@
This library is only intended to be used by UEFI network stack modules.
It provides basic functions for the UEFI network stack.
-Copyright (c) 2005 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2005 - 2017, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at<BR>
@@ -1610,10 +1610,10 @@ typedef struct {
(sizeof (NET_BUF) + ((BlockOpNum) - 1) * sizeof (NET_BLOCK_OP))
#define NET_HEADSPACE(BlockOp) \
- (UINTN)((BlockOp)->Head - (BlockOp)->BlockHead)
+ ((UINTN)((BlockOp)->Head) - (UINTN)((BlockOp)->BlockHead))
#define NET_TAILSPACE(BlockOp) \
- (UINTN)((BlockOp)->BlockTail - (BlockOp)->Tail)
+ ((UINTN)((BlockOp)->BlockTail) - (UINTN)((BlockOp)->Tail))
/**
Allocate a single block NET_BUF. Upon allocation, all the
diff --git a/MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleLib.c b/MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleLib.c
index 71e05bd..d7abcc8 100644
--- a/MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleLib.c
+++ b/MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleLib.c
@@ -10,7 +10,7 @@
ValidateFmpCapsule(), DisplayCapsuleImage(), ConvertBmpToGopBlt() will
receive untrusted input and do basic validation.
- Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
+ Copyright (c) 2016 - 2017, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -547,7 +547,7 @@ ConvertBmpToGopBlt (
}
- ImageIndex = (UINTN) (Image - ImageHeader);
+ ImageIndex = (UINTN) Image - (UINTN) ImageHeader;
if ((ImageIndex % 4) != 0) {
//
// Bmp Image starts each row on a 32-bit boundary!
diff --git a/MdeModulePkg/Library/DxePrintLibPrint2Protocol/PrintLib.c b/MdeModulePkg/Library/DxePrintLibPrint2Protocol/PrintLib.c
index 0137868..7fda260 100644
--- a/MdeModulePkg/Library/DxePrintLibPrint2Protocol/PrintLib.c
+++ b/MdeModulePkg/Library/DxePrintLibPrint2Protocol/PrintLib.c
@@ -205,7 +205,7 @@ DxePrintLibPrint2ProtocolVaListToBaseList (
//
// If BASE_LIST is larger than Size, then return FALSE
//
- if ((UINTN)((UINT8 *)BaseListMarker - (UINT8 *)BaseListStart) > Size) {
+ if (((UINTN)BaseListMarker - (UINTN)BaseListStart) > Size) {
DEBUG ((DEBUG_ERROR, "The input variable argument list is too long. Please consider breaking into multiple print calls.\n"));
return FALSE;
}
diff --git a/MdeModulePkg/Library/FileExplorerLib/FileExplorer.c b/MdeModulePkg/Library/FileExplorerLib/FileExplorer.c
index 41a22aa..d4da998 100644
--- a/MdeModulePkg/Library/FileExplorerLib/FileExplorer.c
+++ b/MdeModulePkg/Library/FileExplorerLib/FileExplorer.c
@@ -1,7 +1,7 @@
/** @file
File explorer related functions.
-Copyright (c) 2004 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2004 - 2017, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials are licensed and made available under
the terms and conditions of the BSD License that accompanies this distribution.
The full text of the license may be found at
@@ -657,7 +657,7 @@ LibAppendFileName (
// that overlap.
//
StrCpyS (TmpStr, MaxLen, Ptr + 3);
- StrCpyS (LastSlash, MaxLen - (UINTN) (LastSlash - Str), TmpStr);
+ StrCpyS (LastSlash, MaxLen - ((UINTN) LastSlash - (UINTN) Str) / sizeof (CHAR16), TmpStr);
Ptr = LastSlash;
} else if (*Ptr == '\\' && *(Ptr + 1) == '.' && *(Ptr + 2) == '\\') {
//
@@ -669,7 +669,7 @@ LibAppendFileName (
// that overlap.
//
StrCpyS (TmpStr, MaxLen, Ptr + 2);
- StrCpyS (Ptr, MaxLen - (UINTN) (Ptr - Str), TmpStr);
+ StrCpyS (Ptr, MaxLen - ((UINTN) Ptr - (UINTN) Str) / sizeof (CHAR16), TmpStr);
Ptr = LastSlash;
} else if (*Ptr == '\\') {
LastSlash = Ptr;
diff --git a/MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c b/MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c
index 5698c91..1f8aaf4 100644
--- a/MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c
+++ b/MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c
@@ -1,7 +1,7 @@
/** @file
Save the S3 data to S3 boot script.
- Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
+ Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions
@@ -2025,7 +2025,7 @@ S3BootScriptCalculateInsertAddress (
// calculate the Position offset
//
if (Position != NULL) {
- PositionOffset = (UINTN) ((UINT8 *)Position - S3TableBase);
+ PositionOffset = (UINTN)Position - (UINTN)S3TableBase;
//
// If the BeforeOrAfter is FALSE, that means to insert the node right after the node.
diff --git a/MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c b/MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c
index 6f705bd..116cf28 100644
--- a/MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c
+++ b/MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c
@@ -1,7 +1,7 @@
/** @file
Load option library functions which relate with creating and processing load options.
-Copyright (c) 2011 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2011 - 2017, Intel Corporation. All rights reserved.<BR>
(C) Copyright 2015-2016 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
@@ -912,7 +912,7 @@ EfiBootManagerVariableToLoadOptionEx (
FilePath = (EFI_DEVICE_PATH_PROTOCOL *) VariablePtr;
VariablePtr += FilePathSize;
- OptionalDataSize = (UINT32) (VariableSize - (UINTN) (VariablePtr - Variable));
+ OptionalDataSize = (UINT32) (VariableSize - ((UINTN) VariablePtr - (UINTN) Variable));
if (OptionalDataSize == 0) {
OptionalData = NULL;
} else {
diff --git a/MdeModulePkg/Universal/DebugPortDxe/DebugPort.c b/MdeModulePkg/Universal/DebugPortDxe/DebugPort.c
index 298b6b2..dcb623c 100644
--- a/MdeModulePkg/Universal/DebugPortDxe/DebugPort.c
+++ b/MdeModulePkg/Universal/DebugPortDxe/DebugPort.c
@@ -4,7 +4,7 @@
ALL CODE IN THE SERIALIO STACK MUST BE RE-ENTRANT AND CALLABLE FROM
INTERRUPT CONTEXT
-Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -569,7 +569,7 @@ DebugPortRead (
LocalBufferSize = *BufferSize - (BufferPtr - (UINT8 *) Buffer);
} while (LocalBufferSize != 0 && Timeout > 0);
- *BufferSize = (UINTN) (BufferPtr - (UINT8 *) Buffer);
+ *BufferSize = (UINTN) BufferPtr - (UINTN) Buffer;
return Status;
}
diff --git a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c
index 2e3e8c7..49e747b 100644
--- a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c
+++ b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c
@@ -3,7 +3,7 @@
These are the common Fault Tolerant Write (FTW) functions that are shared
by DXE FTW driver and SMM FTW driver.
-Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -373,7 +373,7 @@ FtwWrite (
//
// If Record is out of the range of Header, return access denied.
//
- if (((UINTN)((UINT8 *) Record - (UINT8 *) Header)) > FTW_WRITE_TOTAL_SIZE (Header->NumberOfWrites - 1, Header->PrivateDataSize)) {
+ if (((UINTN) Record - (UINTN) Header) > FTW_WRITE_TOTAL_SIZE (Header->NumberOfWrites - 1, Header->PrivateDataSize)) {
return EFI_ACCESS_DENIED;
}
diff --git a/MdeModulePkg/Universal/HiiDatabaseDxe/Image.c b/MdeModulePkg/Universal/HiiDatabaseDxe/Image.c
index 1668828..e2fa16e 100644
--- a/MdeModulePkg/Universal/HiiDatabaseDxe/Image.c
+++ b/MdeModulePkg/Universal/HiiDatabaseDxe/Image.c
@@ -2,7 +2,7 @@
Implementation for EFI_HII_IMAGE_PROTOCOL.
-Copyright (c) 2007 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2007 - 2017, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -1124,7 +1124,7 @@ HiiSetImage (
return EFI_OUT_OF_RESOURCES;
}
- Part1Size = (UINT32) (UINTN) ((UINT8 *) CurrentImageBlock - (UINT8 *) ImagePackage->ImageBlock);
+ Part1Size = (UINT32) ((UINTN) CurrentImageBlock - (UINTN) ImagePackage->ImageBlock);
Part2Size = ImagePackage->ImageBlockSize - Part1Size - OldBlockSize;
CopyMem (ImageBlocks, ImagePackage->ImageBlock, Part1Size);
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
index f5b6a5f..b0c7434 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
@@ -16,7 +16,7 @@
VariableServiceSetVariable() should also check authenticate data to avoid buffer overflow,
integer overflow. It should also check attribute to avoid authentication bypass.
-Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 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
@@ -1170,7 +1170,7 @@ Reclaim (
// Install the new variable if it is not NULL.
//
if (NewVariable != NULL) {
- if ((UINTN) (CurrPtr - ValidBuffer) + NewVariableSize > VariableStoreHeader->Size) {
+ if (((UINTN) CurrPtr - (UINTN) ValidBuffer) + NewVariableSize > VariableStoreHeader->Size) {
//
// No enough space to store the new variable.
//
@@ -1211,8 +1211,8 @@ Reclaim (
// If volatile variable store, just copy valid buffer.
//
SetMem ((UINT8 *) (UINTN) VariableBase, VariableStoreHeader->Size, 0xff);
- CopyMem ((UINT8 *) (UINTN) VariableBase, ValidBuffer, (UINTN) (CurrPtr - ValidBuffer));
- *LastVariableOffset = (UINTN) (CurrPtr - ValidBuffer);
+ CopyMem ((UINT8 *) (UINTN) VariableBase, ValidBuffer, (UINTN) CurrPtr - (UINTN) ValidBuffer);
+ *LastVariableOffset = (UINTN) CurrPtr - (UINTN) ValidBuffer;
Status = EFI_SUCCESS;
} else {
//
@@ -1223,7 +1223,7 @@ Reclaim (
(VARIABLE_STORE_HEADER *) ValidBuffer
);
if (!EFI_ERROR (Status)) {
- *LastVariableOffset = (UINTN) (CurrPtr - ValidBuffer);
+ *LastVariableOffset = (UINTN) CurrPtr - (UINTN) ValidBuffer;
mVariableModuleGlobal->HwErrVariableTotalSize = HwErrVariableTotalSize;
mVariableModuleGlobal->CommonVariableTotalSize = CommonVariableTotalSize;
mVariableModuleGlobal->CommonUserVariableTotalSize = CommonUserVariableTotalSize;
--
1.9.5.msysgit.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v2 0/6] Refine type cast for pointer subtraction
2017-01-25 5:28 [PATCH v2 0/6] Refine type cast for pointer subtraction Hao Wu
2017-01-25 5:28 ` [PATCH v2 1/6] MdeModulePkg: " Hao Wu
@ 2017-01-25 5:36 ` Laszlo Ersek
1 sibling, 0 replies; 3+ messages in thread
From: Laszlo Ersek @ 2017-01-25 5:36 UTC (permalink / raw)
To: Hao Wu, edk2-devel
On 01/25/17 06:28, Hao Wu wrote:
> Please note that this patch is maily for feedback collection and only the
> MdeModulePkg part of the series is sent out firstly.
>
>
> V2 refines the commit messages:
> For pointer subtraction, the result is of type "ptrdiff_t". According to
> the C11 standard (Committee Draft - April 12, 2011):
>
> "When two pointers are subtracted, both shall point to elements of the
> same array object, or one past the last element of the array object; the
> result is the difference of the subscripts of the two array elements. The
> size of the result is implementation-defined, and its type (a signed
> integer type) is ptrdiff_t defined in the <stddef.h> header. If the result
> is not representable in an object of that type, the behavior is
> undefined."
>
> In our codes, there are cases that the pointer subtraction is not
> performed by pointers to elements of the same array object. This might
> lead to potential issues, since the behavior is undefined according to C11
> standard.
>
> Also, since the size of type "ptrdiff_t" is implementation-defined. Some
> static code checkers may warn that the pointer subtraction might underflow
> first and then being cast to a bigger size. For example:
>
> UINT8 *Ptr1, *Ptr2;
> UINTN PtrDiff;
> ...
> PtrDiff = (UINTN) (Ptr1 - Ptr2);
>
> The commit will refine the pointer subtraction expressions by casting each
> pointer to UINTN first and then perform the subtraction:
>
> PtrDiff = (UINTN) Ptr1 - (UINTN) Ptr2;
>
This commit message update looks good to me.
For all patches in the series that use this commit message (and perform
the matching source code changes):
Acked-by: Laszlo Ersek <lersek@redhat.com>
Module owners should of course review the patches in detail.
Thanks,
Laszlo
>
> V1:
> For pointer subtraction, the result is of type "ptrdiff_t". According to
> the C11 spec, ptrdiff_t is a signed integer type but its size is
> implementation-defined.
>
> There are cases that the result of pointer subtraction is type casted to
> UINTN, like:
>
> UINT8 *Ptr1, *Ptr2;
> UINTN PtrDiff;
> ...
> PtrDiff = (UINTN) (Ptr1 - Ptr2);
>
> Some static code checkers may warn that the pointer subtraction might
> overflow first and then the result is being cast to a bigger size.
>
> The series will cast each pointer to UINTN first and then perform the
> subtraction:
>
> PtrDiff = (UINTN) Ptr1 - (UINTN) Ptr2;
>
>
> Cc: Laszlo Ersek <lersek@redhat.com>
>
> Hao Wu (6):
> MdeModulePkg: Refine type cast for pointer subtraction
> CryptoPkg: Refine type cast for pointer subtraction
> IntelFrameworkModulePkg: Refine type cast for pointer subtraction
> NetworkPkg: Refine type cast for pointer subtraction
> SecurityPkg: Refine type cast for pointer subtraction
> ShellPkg: Refine type cast for pointer subtraction
>
> CryptoPkg/Library/BaseCryptLib/SysCall/RuntimeMemAllocation.c | 6 +++---
> IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyPci.c | 4 ++--
> IntelFrameworkModulePkg/Library/GenericBdsLib/BdsBoot.c | 4 ++--
> IntelFrameworkModulePkg/Library/GenericBdsLib/BdsConsole.c | 4 ++--
> IntelFrameworkModulePkg/Library/GenericBdsLib/BdsMisc.c | 4 ++--
> IntelFrameworkModulePkg/Library/LegacyBootManagerLib/LegacyBm.c | 4 ++--
> IntelFrameworkModulePkg/Universal/BdsDxe/BootMaint/BootOption.c | 6 +++---
> MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c | 4 ++--
> MdeModulePkg/Include/Library/NetLib.h | 6 +++---
> MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleLib.c | 4 ++--
> MdeModulePkg/Library/DxePrintLibPrint2Protocol/PrintLib.c | 2 +-
> MdeModulePkg/Library/FileExplorerLib/FileExplorer.c | 6 +++---
> MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c | 4 ++--
> MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c | 4 ++--
> MdeModulePkg/Universal/DebugPortDxe/DebugPort.c | 4 ++--
> MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c | 4 ++--
> MdeModulePkg/Universal/HiiDatabaseDxe/Image.c | 4 ++--
> MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c | 10 +++++-----
> NetworkPkg/HttpDxe/HttpImpl.c | 6 +++---
> SecurityPkg/Library/DxeImageVerificationLib/DxeImageVerificationLib.c | 18 +++++++++---------
> SecurityPkg/Library/DxeTpmMeasureBootLib/DxeTpmMeasureBootLib.c | 10 +++++-----
> SecurityPkg/Library/Tpm2CommandLib/Tpm2Help.c | 6 +++---
> SecurityPkg/Tcg/Tcg2Dxe/MeasureBootPeCoff.c | 10 +++++-----
> SecurityPkg/Tcg/TrEEDxe/MeasureBootPeCoff.c | 10 +++++-----
> SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c | 14 +++++++-------
> ShellPkg/Application/Shell/ShellParametersProtocol.c | 6 +++---
> ShellPkg/Library/UefiShellDebug1CommandsLib/DmpStore.c | 4 ++--
> ShellPkg/Library/UefiShellDebug1CommandsLib/SmbiosView/SmbiosView.c | 4 ++--
> ShellPkg/Library/UefiShellDriver1CommandsLib/Dh.c | 4 ++--
> ShellPkg/Library/UefiShellLevel2CommandsLib/Cd.c | 6 +++---
> 30 files changed, 91 insertions(+), 91 deletions(-)
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2017-01-25 5:37 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-01-25 5:28 [PATCH v2 0/6] Refine type cast for pointer subtraction Hao Wu
2017-01-25 5:28 ` [PATCH v2 1/6] MdeModulePkg: " Hao Wu
2017-01-25 5:36 ` [PATCH v2 0/6] " Laszlo Ersek
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox