> -----Original Message----- > From: Laszlo Ersek [mailto:ler...@redhat.com] > Sent: Tuesday, January 24, 2017 5:54 PM > To: Wu, Hao A > Cc: edk2-de...@ml01.01.org > Subject: Re: [edk2] [PATCH v2 1/1] MdePkg: Refine casting expression result to > bigger size > > On 01/24/17 08:25, Hao Wu wrote: > > There are cases that the operands of an expression are all with rank less > > than UINT64/INT64 and the result of the expression is explicitly casted to > > UINT64/INT64 to fit the target size. > > > > An example will be: > > UINT32 a,b; > > // a and b can be any unsigned int type with rank less than UINT64, like > > // UINT8, UINT16, etc. > > UINT64 c; > > c = (UINT64) (a + b); > > > > Some static code checkers may warn that the expression result might > > overflow within the rank of "int" (integer promotions) and the result is > > then cast to a bigger size. > > > > The commit refines codes by the following rules: > > 1). When the expression will not overflow within the rank of "int", remove > > the explicit type casts: > > c = a + b; > > > > 2). When the expression is possible to overflow the range of unsigned int/ > > int: > > c = (UINT64)a + b; > > > > Contributed-under: TianoCore Contribution Agreement 1.0 > > Signed-off-by: Hao Wu <hao.a...@intel.com> > > --- > > MdePkg/Library/BaseLib/String.c | 4 ++-- > > MdePkg/Library/BasePeCoffLib/BasePeCoff.c | 12 > > +++++------- > > MdePkg/Library/BaseS3PciLib/S3PciLib.c | 4 ++-- > > MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c | 4 ++-- > > MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c | 4 ++-- > > 5 files changed, 13 insertions(+), 15 deletions(-) > > > > diff --git a/MdePkg/Library/BaseLib/String.c > b/MdePkg/Library/BaseLib/String.c > > index e84bf50..4151e0e 100644 > > --- a/MdePkg/Library/BaseLib/String.c > > +++ b/MdePkg/Library/BaseLib/String.c > > @@ -586,7 +586,7 @@ InternalHexCharToUintn ( > > return Char - L'0'; > > } > > > > - return (UINTN) (10 + InternalCharToUpper (Char) - L'A'); > > + return (10 + InternalCharToUpper (Char) - L'A'); > > } > > > > /** > > @@ -1211,7 +1211,7 @@ InternalAsciiHexCharToUintn ( > > return Char - '0'; > > } > > > > - return (UINTN) (10 + InternalBaseLibAsciiToUpper (Char) - 'A'); > > + return (10 + InternalBaseLibAsciiToUpper (Char) - 'A'); > > } > > > > > > diff --git a/MdePkg/Library/BasePeCoffLib/BasePeCoff.c > b/MdePkg/Library/BasePeCoffLib/BasePeCoff.c > > index 33cad23..8d1daba 100644 > > --- a/MdePkg/Library/BasePeCoffLib/BasePeCoff.c > > +++ b/MdePkg/Library/BasePeCoffLib/BasePeCoff.c > > @@ -15,7 +15,7 @@ > > PeCoffLoaderGetPeHeader() routine will do basic check for PE/COFF header. > > PeCoffLoaderGetImageInfo() routine will do basic check for whole PE/COFF > image. > > > > - Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR> > > + Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR> > > Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR> > > This program and the accompanying materials > > are licensed and made available under the terms and conditions of the BSD > License > > @@ -703,12 +703,10 @@ PeCoffLoaderGetImageInfo ( > > // > > DebugDirectoryEntryFileOffset = 0; > > > > - SectionHeaderOffset = (UINTN)( > > - ImageContext->PeCoffHeaderOffset + > > - sizeof (UINT32) + > > - sizeof (EFI_IMAGE_FILE_HEADER) + > > - Hdr.Pe32->FileHeader.SizeOfOptionalHeader > > - ); > > + SectionHeaderOffset = ImageContext->PeCoffHeaderOffset + > > + sizeof (UINT32) + > > + sizeof (EFI_IMAGE_FILE_HEADER) + > > + Hdr.Pe32->FileHeader.SizeOfOptionalHeader; > > > > for (Index = 0; Index < Hdr.Pe32->FileHeader.NumberOfSections; > > Index++) > { > > // > > diff --git a/MdePkg/Library/BaseS3PciLib/S3PciLib.c > b/MdePkg/Library/BaseS3PciLib/S3PciLib.c > > index e29f7fe..27342b0 100644 > > --- a/MdePkg/Library/BaseS3PciLib/S3PciLib.c > > +++ b/MdePkg/Library/BaseS3PciLib/S3PciLib.c > > @@ -3,7 +3,7 @@ > > the PCI operations to be replayed during an S3 resume. This library class > > maps directly on top of the PciLib class. > > > > - Copyright (c) 2006 - 2012, 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 > > @@ -25,7 +25,7 @@ > > #include <Library/S3PciLib.h> > > > > #define PCILIB_TO_COMMON_ADDRESS(Address) \ > > - ((UINT64) ((((UINTN) ((Address>>20) & 0xff)) << 24) + (((UINTN) > ((Address>>15) & 0x1f)) << 16) + (((UINTN) ((Address>>12) & 0x07)) << 8) + > ((UINTN) (Address & 0xfff )))) > > + ((((UINTN) ((Address>>20) & 0xff)) << 24) + (((UINTN) > > ((Address>>15) & > 0x1f)) << 16) + (((UINTN) ((Address>>12) & 0x07)) << 8) + ((UINTN) (Address & > 0xfff ))) > > > > /** > > Saves a PCI configuration value to the boot script. > > I think this change is potentially unsafe, without auditing all uses of > PCILIB_TO_COMMON_ADDRESS(). In a 32-bit build, the type of the result > will no longer be UINT64 but UINT32, and that can cause problems in > several contexts. For example: > > - as an operand to the sizeof operator > - when it's being relied upon to cause conversion to UINT64, for example > another (UINT32) operand could be added to it > - when it is passed through a variable argument list > > It might be safe, but there's no way to tell without auditing all the > call sites. So let me see... > > Apparently this macro is only passed to S3BootScriptSavePciCfgWrite() as > second argument, within the same file, and that argument is covered by > the function prototype explicitly, with type UINT64. So the change > should be safe. >
Thanks for the checking. I did search the whole edk2 repository for the reference of "PCILIB_TO_COMMON_ADDRESS" and it is only comsumed by the function you mentioned. > (I see the same macro definition and kind of invocation in > "QuarkPlatformPkg/Acpi/DxeSmm/AcpiSmm/AcpiSmmPlatform.c"; I didn't try > to audit that file.) > > The rest looks okay too. > > Reviewed-by: Laszlo Ersek <ler...@redhat.com> > Many thanks for the feedbacks and the effort for reviewing the patch. > (If you go ahead and submit a 30-part series that does this kind of > fixup all over the tree, please don't expect me to review it all -- I'm > okay reviewing OvmfPkg and ArmVirtPkg changes, but I can't take on the > rest. This kind of patch cannot be reviewed without consulting a really > wide context.) > I am thinking if the package level patch contains too many changes, I might break it into multiple module-level patches and include module owners/experts to help reviewing them. Best Regards, Hao Wu > Thanks > Laszlo > > > > diff --git > a/MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c > b/MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c > > index 937165a..592cced 100644 > > --- a/MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c > > +++ b/MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c > > @@ -12,7 +12,7 @@ > > allocation for the Reserved memory types are not supported and will > always > > return NULL. > > > > - 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 > > @@ -343,7 +343,7 @@ InternalAllocateAlignedPages ( > > Status = gSmst->SmmFreePages (Memory, UnalignedPages); > > ASSERT_EFI_ERROR (Status); > > } > > - Memory = (EFI_PHYSICAL_ADDRESS) (AlignedMemory + > EFI_PAGES_TO_SIZE (Pages)); > > + Memory = AlignedMemory + EFI_PAGES_TO_SIZE (Pages); > > UnalignedPages = RealPages - Pages - UnalignedPages; > > if (UnalignedPages > 0) { > > // > > diff --git a/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c > b/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c > > index 3da5e211..3bd3aef 100644 > > --- a/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c > > +++ b/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c > > @@ -2,7 +2,7 @@ > > Support routines for memory allocation routines based > > on boot services for Dxe phase drivers. > > > > - 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 > > @@ -216,7 +216,7 @@ InternalAllocateAlignedPages ( > > Status = gBS->FreePages (Memory, UnalignedPages); > > ASSERT_EFI_ERROR (Status); > > } > > - Memory = (EFI_PHYSICAL_ADDRESS) (AlignedMemory + > EFI_PAGES_TO_SIZE (Pages)); > > + Memory = AlignedMemory + EFI_PAGES_TO_SIZE (Pages); > > UnalignedPages = RealPages - Pages - UnalignedPages; > > if (UnalignedPages > 0) { > > // > > _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel