I haven't got time to do it in automatic way. V1 may need a shell app to check it, but current implementation might not need it because we now have 2 or 3 continuous 2MB pages to hold all page tables. We just need to verify the page attribute of those 2 or 3 page tables. It's easy to do it in a JTAG debugger manually.
> -----Original Message----- > From: Yao, Jiewen > Sent: Tuesday, December 05, 2017 10:32 AM > To: Wang, Jian J <jian.j.w...@intel.com>; edk2-devel@lists.01.org > Cc: Yao, Jiewen <jiewen....@intel.com> > Subject: RE: [edk2] [PATCH v2 0/4] Enable page table write protection > > Hi Jian > In V1 review, I suggest to test in UEFI shell env to make sure all page table > is > read only, with PageTable split in CPU driver. > > May I know if that is done? > > Thank you > Yao Jiewen > > > -----Original Message----- > > From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of Jian > J > > Wang > > Sent: Monday, December 4, 2017 4:36 PM > > To: edk2-devel@lists.01.org > > Subject: [edk2] [PATCH v2 0/4] Enable page table write protection > > > > > v2 changes: > > > a. Enable protection on any newly added page table after DxeIpl. > > > b. Introduce page table pool concept to make page table allocation > > > and protection easier and error free. > > > > Write Protect feature (CR0.WP) is always enabled in driver > UefiCpuPkg/CpuDxe. > > But the memory pages used for page table are not set as read-only in the > driver > > DxeIplPeim, after the paging is setup. This might jeopardize the page table > > integrity if there's buffer overflow occured in other part of system. > > > > This patch series will change this situation by clearing R/W bit in page > > attribute > > of the pages used as page table. > > > > Validation works include booting Windows (10/server 2016) and Linux > > (Fedora/Ubuntu) > > on OVMF and Intel real platform. > > > > Jian J Wang (4): > > MdeModulePkg/MdeModulePkg.dec: Add new PCDs and Guid > > MdeModulePkg/PageTablePool.h: Page table pool GUID definition file > > MdeModulePkg/DxeIpl: Mark page table as read-only > > UefiCpuPkg/CpuDxe: Enable protection for newly added page table > > > > MdeModulePkg/Core/DxeIplPeim/DxeIpl.h | 34 +++ > > MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf | 3 + > > MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c | 8 +- > > MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c | 315 > > +++++++++++++++++++++- > > MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.h | 15 ++ > > MdeModulePkg/Include/Guid/PageTablePool.h | 53 ++++ > > MdeModulePkg/MdeModulePkg.dec | 28 ++ > > UefiCpuPkg/CpuDxe/CpuDxe.c | 17 +- > > UefiCpuPkg/CpuDxe/CpuDxe.h | 2 + > > UefiCpuPkg/CpuDxe/CpuDxe.inf | 3 + > > UefiCpuPkg/CpuDxe/CpuPageTable.c | 329 > > ++++++++++++++++++++++- > > UefiCpuPkg/CpuDxe/CpuPageTable.h | 22 ++ > > 12 files changed, 816 insertions(+), 13 deletions(-) > > create mode 100644 MdeModulePkg/Include/Guid/PageTablePool.h > > > > -- > > 2.14.1.windows.1 > > > > _______________________________________________ > > edk2-devel mailing list > > edk2-devel@lists.01.org > > https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
