Yes. The change is necessary.
> -----Original Message----- > From: Ard Biesheuvel [mailto:ard.biesheu...@linaro.org] > Sent: Wednesday, December 5, 2018 3:42 PM > To: Gao, Liming <liming....@intel.com> > Cc: Laszlo Ersek <ler...@redhat.com>; edk2-devel@lists.01.org; Zhu, Yonghong > <yonghong....@intel.com>; Feng, Bob C > <bob.c.f...@intel.com>; Carsey, Jaben <jaben.car...@intel.com> > Subject: Re: [PATCH v2 4/6] BaseTools/DevicePath: use MAX_UINT16 as default > device path max size > > On Wed, 5 Dec 2018 at 01:04, Gao, Liming <liming....@intel.com> wrote: > > > > Laszlo: > > I agree with you. MAX_UINT32 is more comfortable. > > > > Liming, > > No definitions for MAX_UINT32 exist currently in BaseTools, so I will > have to add the following: > > diff --git a/BaseTools/Source/C/Common/CommonLib.h > b/BaseTools/Source/C/Common/CommonLib.h > index b1c6c00a3478..1c40180329c4 100644 > --- a/BaseTools/Source/C/Common/CommonLib.h > +++ b/BaseTools/Source/C/Common/CommonLib.h > @@ -23,6 +23,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, > EITHER EXPRESS OR IMPLIED. > #define MAX_LONG_FILE_PATH 500 > > #define MAX_UINT64 ((UINT64)0xFFFFFFFFFFFFFFFFULL) > +#define MAX_UINT32 ((UINT32)0xFFFFFFFFULL) > #define MAX_UINT16 ((UINT16)0xFFFF) > #define MAX_UINT8 ((UINT8)0xFF) > #define ARRAY_SIZE(Array) (sizeof (Array) / sizeof ((Array)[0])) > > Does your Reviewed-by cover that as well? > > > > > > >-----Original Message----- > > >From: Laszlo Ersek [mailto:ler...@redhat.com] > > >Sent: Monday, December 03, 2018 9:06 PM > > >To: Ard Biesheuvel <ard.biesheu...@linaro.org>; edk2-devel@lists.01.org > > >Cc: Zhu, Yonghong <yonghong....@intel.com>; Gao, Liming > > ><liming....@intel.com>; Feng, Bob C <bob.c.f...@intel.com>; Carsey, Jaben > > ><jaben.car...@intel.com> > > >Subject: Re: [PATCH v2 4/6] BaseTools/DevicePath: use MAX_UINT16 as > > >default device path max size > > > > > >On 11/30/18 23:45, Ard Biesheuvel wrote: > > >> Replace the default size limit of IsDevicePathValid() with a value > > >> that does not depend on the native word size of the build host. > > >> > > >> 64 KB seems sufficient as the upper bound of a device path handled > > >> by UEFI. > > >> > > >> Contributed-under: TianoCore Contribution Agreement 1.1 > > >> Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org> > > >> Reviewed-by: Jaben Carsey <jaben.car...@intel.com> > > >> --- > > >> BaseTools/Source/C/DevicePath/DevicePathUtilities.c | 4 ++-- > > >> 1 file changed, 2 insertions(+), 2 deletions(-) > > >> > > >> diff --git a/BaseTools/Source/C/DevicePath/DevicePathUtilities.c > > >b/BaseTools/Source/C/DevicePath/DevicePathUtilities.c > > >> index d4ec2742b7c8..ba7f83e53070 100644 > > >> --- a/BaseTools/Source/C/DevicePath/DevicePathUtilities.c > > >> +++ b/BaseTools/Source/C/DevicePath/DevicePathUtilities.c > > >> @@ -62,7 +62,7 @@ IsDevicePathValid ( > > >> ASSERT (DevicePath != NULL); > > >> > > >> if (MaxSize == 0) { > > >> - MaxSize = MAX_UINTN; > > >> + MaxSize = MAX_UINT16; > > >> } > > >> > > >> // > > >> @@ -78,7 +78,7 @@ IsDevicePathValid ( > > >> return FALSE; > > >> } > > >> > > >> - if (NodeLength > MAX_UINTN - Size) { > > >> + if (NodeLength > MAX_UINT16 - Size) { > > >> return FALSE; > > >> } > > >> Size += NodeLength; > > >> > > > > > >I'm somewhat undecided about this patch. > > > > > >(1) IsDevicePathValid() also exists in: > > > > > >- MdePkg/Library/UefiDevicePathLib/DevicePathUtilities.c > > >- MdePkg/Library/UefiDevicePathLibDevicePathProtocol/UefiDevicePathLib.c > > > > > >Both have: > > > > > > if (MaxSize == 0) { > > > MaxSize = MAX_UINTN; > > > } > > > > > >Relative to those, this change departs quite strongly. > > > > > > > > >(2) In addition, a single device path node may extend up to 64KB. That > > >would be pathologic, yes, but the option is there. > > > > > > > > >... Of course, we are discussing theoretical limits. Still I'd feel more > > >comfortable with MAX_UINT32. Lifting the limit from 64K to 4G wouldn't > > >cost us anything (in development effort), it would be a no-op on 32-bit > > >build hosts, it would be a theoretical-only change on 64-bit build > > >hosts, and it would leave us with a larger "safety margin". > > > > > >I won't insist, but I thought I should raise this. (Sorry if this has > > >been discussed under v1 already.) If you agree, no need to repost (from > > >my side anyway) just for this. > > > > > >With or without the update: > > > > > >Reviewed-by: Laszlo Ersek <ler...@redhat.com> > > > > > >Thanks > > >Laszlo _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
