REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1521
We scan the SMM code with ROPgadget. http://shell-storm.org/project/ROPgadget/ https://github.com/JonathanSalwan/ROPgadget/tree/master This tool reports the gadget in SMM driver. This patch enabled CET ShadowStack for X86 SMM. If CET is supported, SMM will enable CET ShadowStack. SMM CET will save the OS CET context at SmmEntry and restore OS CET context at SmmExit. Test: 1) test Intel internal platform (x64 only, CET enabled/disabled) Boot test: CET supported or not supported CPU on CET supported platform CET enabled/disabled PcdCpuSmmCetEnable enabled/disabled Single core/Multiple core PcdCpuSmmStackGuard enabled/disabled PcdCpuSmmProfileEnable enabled/disabled PcdCpuSmmStaticPageTable enabled/disabled CET exception test: #CF generated with PcdCpuSmmStackGuard enabled/disabled. Other exception test: #PF for normal stack overflow #PF for NX protection #PF for RO protection CET env test: Launch SMM in CET enabled/disabled environment (DXE) - no impact to DXE The test case can be found at https://github.com/jyao1/SecurityEx/tree/master/ControlFlowPkg 2) test ovmf (both IA32 and X64 SMM, CET disabled only) test OvmfIa32/Ovmf3264, with -D SMM_REQUIRE. qemu-system-x86_64.exe -machine q35,smm=on -smp 4 -serial file:serial.log -drive if=pflash,format=raw,unit=0,file=OVMF_CODE.fd,readonly=on -drive if=pflash,format=raw,unit=1,file=OVMF_VARS.fd QEMU emulator version 3.1.0 (v3.1.0-11736-g7a30e7adb0-dirty) 3) not tested IA32 CET enabled platform Cc: Eric Dong <eric.d...@intel.com> Cc: Ray Ni <ray...@intel.com> Cc: Laszlo Ersek <ler...@redhat.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Yao Jiewen <jiewen....@intel.com> --- UefiCpuPkg/Include/Library/SmmCpuFeaturesLib.h | 23 +++- UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/Cet.nasm | 37 ++++++ UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c | 38 ++++++- UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm | 98 +++++++++++++++- UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiException.nasm | 6 +- UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c | 57 +++++++++- UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c | 12 +- UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c | 97 ++++++++++++++-- UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h | 103 ++++++++++++++++- UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf | 6 +- UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c | 85 +++++++++++++- UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c | 18 ++- UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.h | 4 +- UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c | 4 +- UefiCpuPkg/PiSmmCpuDxeSmm/X64/Cet.nasm | 38 +++++++ UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c | 39 ++++++- UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm | 119 +++++++++++++++++++- UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c | 58 +++++++++- UefiCpuPkg/UefiCpuPkg.dec | 13 ++- 19 files changed, 808 insertions(+), 47 deletions(-) diff --git a/UefiCpuPkg/Include/Library/SmmCpuFeaturesLib.h b/UefiCpuPkg/Include/Library/SmmCpuFeaturesLib.h index 4478003467..aec24b5dda 100644 --- a/UefiCpuPkg/Include/Library/SmmCpuFeaturesLib.h +++ b/UefiCpuPkg/Include/Library/SmmCpuFeaturesLib.h @@ -1,7 +1,7 @@ /** @file Library that provides CPU specific functions to support the PiSmmCpuDxeSmm module. -Copyright (c) 2015, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2015 - 2019, 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 @@ -160,14 +160,33 @@ SmmCpuFeaturesGetSmiHandlerSize ( than zero and is called by the CPU that was elected as monarch during System Management Mode initialization. + // + // Append Shadow Stack after normal stack + // + // |= SmiStack + // +--------------------------------------------------+---------------------------------------------------------------+ + // | Known Good Stack | Guard Page | SMM Stack | Known Good Shadow Stack | Guard Page | SMM Shadow Stack | + // +--------------------------------------------------+---------------------------------------------------------------+ + // | |PcdCpuSmmStackSize| |PcdCpuSmmShadowStackSize| + // |<-------------------- StackSize ----------------->|<------------------------- ShadowStackSize ------------------->| + // | | + // |<-------------------------------------------- Processor N ------------------------------------------------------->| + // | low address (bottom) high address (top) | + // + @param[in] CpuIndex The index of the CPU to install the custom SMI handler. The value must be between 0 and the NumberOfCpus field in the System Management System Table (SMST). @param[in] SmBase The SMBASE address for the CPU specified by CpuIndex. - @param[in] SmiStack The stack to use when an SMI is processed by the + @param[in] SmiStack The bottom of stack to use when an SMI is processed by the the CPU specified by CpuIndex. @param[in] StackSize The size, in bytes, if the stack used when an SMI is processed by the CPU specified by CpuIndex. + StackSize should be PcdCpuSmmStackSize, with 2 more pages + if PcdCpuSmmStackGuard is true. + If ShadowStack is enabled, the shadow stack is allocated + after the normal Stack. The size is PcdCpuSmmShadowStackSize. + with 2 more pages if PcdCpuSmmStackGuard is true. @param[in] GdtBase The base address of the GDT to use when an SMI is processed by the CPU specified by CpuIndex. @param[in] GdtSize The size, in bytes, of the GDT used when an SMI is diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/Cet.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/Cet.nasm new file mode 100644 index 0000000000..b26bda9dfb --- /dev/null +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/Cet.nasm @@ -0,0 +1,37 @@ +;------------------------------------------------------------------------------ ; +; Copyright (c) 2019, 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 +; http://opensource.org/licenses/bsd-license.php. +; +; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, +; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. +; +;------------------------------------------------------------------------------- + +SECTION .text + +global ASM_PFX(DisableCet) +ASM_PFX(DisableCet): + + ; Skip the pushed data for call + mov eax, 1 + DB 0xF3, 0x0F, 0xAE, 0xE8 ; INCSSP RAX + + mov eax, cr4 + btr eax, 23 ; clear CET + mov cr4, eax + ret + +global ASM_PFX(EnableCet) +ASM_PFX(EnableCet): + + mov eax, cr4 + bts eax, 23 ; set CET + mov cr4, eax + + ; use jmp to skip the check for ret + pop eax + jmp eax + diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c index a32b736089..b734a1ea8c 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c @@ -1,7 +1,7 @@ /** @file Page table manipulation functions for IA-32 processors -Copyright (c) 2009 - 2017, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2009 - 2019, Intel Corporation. All rights reserved.<BR> Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR> This program and the accompanying materials @@ -16,6 +16,24 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. #include "PiSmmCpuDxeSmm.h" +/** + Disable CET. +**/ +VOID +EFIAPI +DisableCet ( + VOID + ); + +/** + Enable CET. +**/ +VOID +EFIAPI +EnableCet ( + VOID + ); + /** Create PageTable for SMM use. @@ -138,6 +156,7 @@ SmiPFHandler ( } } CpuDeadLoop (); + goto Exit; } // @@ -152,6 +171,7 @@ SmiPFHandler ( DumpModuleInfoByIp (*(UINTN *)(UINTN)SystemContext.SystemContextIa32->Esp); ); CpuDeadLoop (); + goto Exit; } // @@ -171,6 +191,7 @@ SmiPFHandler ( } CpuDeadLoop (); + goto Exit; } if (IsSmmCommBufferForbiddenAddress (PFAddress)) { @@ -180,6 +201,7 @@ SmiPFHandler ( DumpModuleInfoByIp ((UINTN)SystemContext.SystemContextIa32->Eip); ); CpuDeadLoop (); + goto Exit; } } @@ -212,6 +234,7 @@ SetPageTableAttributes ( UINT64 *L3PageTable; BOOLEAN IsSplitted; BOOLEAN PageTableSplitted; + BOOLEAN CetEnabled; // // Don't mark page table to read-only if heap guard is enabled. @@ -238,6 +261,13 @@ SetPageTableAttributes ( // Disable write protection, because we need mark page table to be write protected. // We need *write* page table memory, to mark itself to be *read only*. // + CetEnabled = ((AsmReadCr4() & CR4_CET_ENABLE) != 0) ? TRUE : FALSE; + if (CetEnabled) { + // + // CET must be disabled if WP is disabled. + // + DisableCet(); + } AsmWriteCr0 (AsmReadCr0() & ~CR0_WP); do { @@ -277,6 +307,12 @@ SetPageTableAttributes ( // Enable write protection, after page table updated. // AsmWriteCr0 (AsmReadCr0() | CR0_WP); + if (CetEnabled) { + // + // re-enable CET. + // + EnableCet(); + } return ; } diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm index 3791cfa144..9a629219eb 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm @@ -1,5 +1,5 @@ ;------------------------------------------------------------------------------ ; -; Copyright (c) 2016 - 2018, Intel Corporation. All rights reserved.<BR> +; Copyright (c) 2016 - 2019, 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 @@ -20,6 +20,19 @@ %include "StuffRsbNasm.inc" +%define MSR_IA32_S_CET 0x6A2 +%define MSR_IA32_CET_SH_STK_EN 0x1 +%define MSR_IA32_CET_WR_SHSTK_EN 0x2 +%define MSR_IA32_CET_ENDBR_EN 0x4 +%define MSR_IA32_CET_LEG_IW_EN 0x8 +%define MSR_IA32_CET_NO_TRACK_EN 0x10 +%define MSR_IA32_CET_SUPPRESS_DIS 0x20 +%define MSR_IA32_CET_SUPPRESS 0x400 +%define MSR_IA32_CET_TRACKER 0x800 +%define MSR_IA32_PL0_SSP 0x6A4 + +%define CR4_CET 0x800000 + %define MSR_IA32_MISC_ENABLE 0x1A0 %define MSR_EFER 0xc0000080 %define MSR_EFER_XD 0x800 @@ -53,6 +66,11 @@ extern ASM_PFX(mXdSupported) global ASM_PFX(gPatchXdSupported) extern ASM_PFX(gSmiHandlerIdtr) +extern ASM_PFX(mCetSupported) +global ASM_PFX(mPatchCetSupported) +global ASM_PFX(mPatchCetPl0Ssp) +global ASM_PFX(mPatchCetInterruptSsp) + SECTION .text BITS 16 @@ -173,11 +191,61 @@ ASM_PFX(gPatchXdSupported): mov ax, [ebx + DSC_SS] mov ss, eax -; jmp _SmiHandler ; instruction is not needed + mov ebx, [esp + 4] ; ebx <- CpuIndex + +; enable CET if supported + mov al, strict byte 1 ; source operand may be patched +ASM_PFX(mPatchCetSupported): + cmp al, 0 + jz CetDone + + mov ecx, MSR_IA32_S_CET + rdmsr + push edx + push eax + + mov ecx, MSR_IA32_PL0_SSP + rdmsr + push edx + push eax + + mov ecx, MSR_IA32_S_CET + mov eax, MSR_IA32_CET_SH_STK_EN + xor edx, edx + wrmsr + + mov ecx, MSR_IA32_PL0_SSP + mov eax, strict dword 0 ; source operand will be patched +ASM_PFX(mPatchCetPl0Ssp): + xor edx, edx + wrmsr + mov ecx, cr0 + btr ecx, 16 ; clear WP + mov cr0, ecx + mov [eax], eax ; reload SSP, and clear busyflag. + xor ecx, ecx + mov [eax + 4], ecx + + mov eax, strict dword 0 ; source operand will be patched +ASM_PFX(mPatchCetInterruptSsp): + cmp eax, 0 + jz CetInterruptDone + mov [eax], eax ; reload SSP, and clear busyflag. + xor ecx, ecx + mov [eax + 4], ecx +CetInterruptDone: + + mov ecx, cr0 + bts ecx, 16 ; set WP + mov cr0, ecx + + mov eax, 0x668 | CR4_CET + mov cr4, eax + + DB 0xF3, 0x0F, 0x01, 0xE8 ; SETSSBSY + +CetDone: -global ASM_PFX(SmiHandler) -ASM_PFX(SmiHandler): - mov ebx, [esp + 4] ; CPU Index push ebx mov eax, ASM_PFX(CpuSmmDebugEntry) call eax @@ -193,6 +261,25 @@ ASM_PFX(SmiHandler): call eax add esp, 4 + mov eax, ASM_PFX(mCetSupported) + mov al, [eax] + cmp al, 0 + jz CetDone2 + + mov eax, 0x668 + mov cr4, eax ; disable CET + + mov ecx, MSR_IA32_PL0_SSP + pop eax + pop edx + wrmsr + + mov ecx, MSR_IA32_S_CET + pop eax + pop edx + wrmsr +CetDone2: + mov eax, ASM_PFX(mXdSupported) mov al, [eax] cmp al, 0 @@ -206,6 +293,7 @@ ASM_PFX(SmiHandler): wrmsr .7: + StuffRsb32 rsm diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiException.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiException.nasm index 879fa0ba63..97a5fcad32 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiException.nasm +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiException.nasm @@ -1,5 +1,5 @@ ;------------------------------------------------------------------------------ ; -; Copyright (c) 2009 - 2016, Intel Corporation. All rights reserved.<BR> +; Copyright (c) 2009 - 2019, 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 @@ -89,7 +89,7 @@ TssSeg: DB 0x80 ; LimitHigh DB 0 ; BaseHigh ExceptionTssSeg: - DW TSS_DESC_SIZE ; LimitLow + DW EXCEPTION_TSS_DESC_SIZE ; LimitLow DW 0 ; BaseLow DB 0 ; BaseMid DB 0x89 @@ -223,6 +223,8 @@ ExceptionTssDescriptor: DW 0 ; Reserved DW 0 ; T DW 0 ; I/O Map Base + DD 0 ; SSP +EXCEPTION_TSS_DESC_SIZE equ $ - ExceptionTssDescriptor ASM_PFX(gcPsd): DB 'PSDSIG ' diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c index 4f1f67fe4a..d43e6c73da 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c @@ -1,7 +1,7 @@ /** @file SMM CPU misc functions for Ia32 arch specific. -Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2015 - 2019, 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 @@ -19,6 +19,14 @@ extern UINT64 gTaskGateDescriptor; EFI_PHYSICAL_ADDRESS mGdtBuffer; UINTN mGdtBufferSize; +extern BOOLEAN mCetSupported; +extern UINTN mSmmShadowStackSize; + +X86_ASSEMBLY_PATCH_LABEL mPatchCetPl0Ssp; +X86_ASSEMBLY_PATCH_LABEL mPatchCetInterruptSsp; +UINT32 mCetPl0Ssp; +UINT32 mCetInterruptSsp; + /** Initialize IDT for SMM Stack Guard. @@ -62,6 +70,7 @@ InitGdt ( UINTN GdtTssTableSize; UINT8 *GdtTssTables; UINTN GdtTableStepSize; + UINTN InterruptShadowStack; if (FeaturePcdGet (PcdCpuSmmStackGuard)) { // @@ -75,7 +84,7 @@ InitGdt ( // gcSmiGdtr.Limit += (UINT16)(2 * sizeof (IA32_SEGMENT_DESCRIPTOR)); - GdtTssTableSize = (gcSmiGdtr.Limit + 1 + TSS_SIZE * 2 + 7) & ~7; // 8 bytes aligned + GdtTssTableSize = (gcSmiGdtr.Limit + 1 + TSS_SIZE + EXCEPTION_TSS_SIZE + 7) & ~7; // 8 bytes aligned mGdtBufferSize = GdtTssTableSize * gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus; // // IA32 Stack Guard need use task switch to switch stack that need @@ -88,7 +97,7 @@ InitGdt ( GdtTableStepSize = GdtTssTableSize; for (Index = 0; Index < gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus; Index++) { - CopyMem (GdtTssTables + GdtTableStepSize * Index, (VOID*)(UINTN)gcSmiGdtr.Base, gcSmiGdtr.Limit + 1 + TSS_SIZE * 2); + CopyMem (GdtTssTables + GdtTableStepSize * Index, (VOID*)(UINTN)gcSmiGdtr.Base, gcSmiGdtr.Limit + 1 + TSS_SIZE + EXCEPTION_TSS_SIZE); // // Fixup TSS descriptors // @@ -110,6 +119,14 @@ InitGdt ( // *(UINTN *)(TssBase + TSS_IA32_ESP_OFFSET) = mSmmStackArrayBase + EFI_PAGE_SIZE + Index * mSmmStackSize; *(UINT32 *)(TssBase + TSS_IA32_CR3_OFFSET) = Cr3; + + // + // Setup ShadowStack for stack switch + // + if (FeaturePcdGet (PcdCpuSmmCetEnable) && mCetSupported) { + InterruptShadowStack = (UINTN)(mSmmStackArrayBase + mSmmStackSize + EFI_PAGES_TO_SIZE (1) - sizeof(UINT64) + (mSmmStackSize + mSmmShadowStackSize) * Index); + *(UINT32 *)(TssBase + TSS_IA32_SSP_OFFSET) = (UINT32)InterruptShadowStack; + } } } else { // @@ -157,3 +174,37 @@ TransferApToSafeState ( // ASSERT (FALSE); } + +/** + Initialize the shadow stack related data structure. + + @param CpuIndex The index of CPU. + @param ShadowStack The bottom of the shadow stack for this CPU. +**/ +VOID +InitShadowStack ( + IN UINTN CpuIndex, + IN VOID *ShadowStack + ) +{ + UINTN SmmShadowStackSize; + + if (FeaturePcdGet (PcdCpuSmmCetEnable) && mCetSupported) { + SmmShadowStackSize = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (PcdGet32 (PcdCpuSmmShadowStackSize))); + if (FeaturePcdGet (PcdCpuSmmStackGuard)) { + SmmShadowStackSize += EFI_PAGES_TO_SIZE (2); + } + mCetPl0Ssp = (UINT32)((UINTN)ShadowStack + SmmShadowStackSize - sizeof(UINT64)); + PatchInstructionX86 (mPatchCetPl0Ssp, mCetPl0Ssp, 4); + DEBUG ((DEBUG_INFO, "mCetPl0Ssp - 0x%x\n", mCetPl0Ssp)); + DEBUG ((DEBUG_INFO, "ShadowStack - 0x%x\n", ShadowStack)); + DEBUG ((DEBUG_INFO, " SmmShadowStackSize - 0x%x\n", SmmShadowStackSize)); + + if (FeaturePcdGet (PcdCpuSmmStackGuard)) { + mCetInterruptSsp = (UINT32)((UINTN)ShadowStack + EFI_PAGES_TO_SIZE(1) - sizeof(UINT64)); + PatchInstructionX86 (mPatchCetInterruptSsp, mCetInterruptSsp, 4); + DEBUG ((DEBUG_INFO, "mCetInterruptSsp - 0x%x\n", mCetInterruptSsp)); + } + } +} + diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c b/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c index abcc3eea05..3b0b3b52ac 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c @@ -1,7 +1,7 @@ /** @file SMM MP service implementation -Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2009 - 2019, Intel Corporation. All rights reserved.<BR> Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR> This program and the accompanying materials @@ -1369,14 +1369,16 @@ InitializeMpSyncData ( /** Initialize global data for MP synchronization. - @param Stacks Base address of SMI stack buffer for all processors. - @param StackSize Stack size for each processor in SMM. + @param Stacks Base address of SMI stack buffer for all processors. + @param StackSize Stack size for each processor in SMM. + @param ShadowStackSize Shadow Stack size for each processor in SMM. **/ UINT32 InitializeMpServiceData ( IN VOID *Stacks, - IN UINTN StackSize + IN UINTN StackSize, + IN UINTN ShadowStackSize ) { UINT32 Cr3; @@ -1428,7 +1430,7 @@ InitializeMpServiceData ( InstallSmiHandler ( Index, (UINT32)mCpuHotPlugData.SmBase[Index], - (VOID*)((UINTN)Stacks + (StackSize * Index)), + (VOID*)((UINTN)Stacks + (StackSize + ShadowStackSize) * Index), StackSize, (UINTN)(GdtTssTables + GdtTableStepSize * Index), gcSmiGdtr.Limit + 1, diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c index 8c9fa14b5b..feabe6dfa5 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c @@ -1,7 +1,7 @@ /** @file Agent Module to load other modules to deploy SMM Entry Vector for X86 CPU. -Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2009 - 2019, Intel Corporation. All rights reserved.<BR> Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR> This program and the accompanying materials @@ -94,6 +94,9 @@ UINTN mSmmStackArrayBase; UINTN mSmmStackArrayEnd; UINTN mSmmStackSize; +UINTN mSmmShadowStackSize; +BOOLEAN mCetSupported = TRUE; + UINTN mMaxNumberOfCpus = 1; UINTN mNumberOfCpus = 1; @@ -420,7 +423,7 @@ SmmRelocateBases ( PatchInstructionX86 (gPatchSmmCr0, mSmmCr0, 4); PatchInstructionX86 (gPatchSmmCr3, AsmReadCr3 (), 4); mSmmCr4 = (UINT32)AsmReadCr4 (); - PatchInstructionX86 (gPatchSmmCr4, mSmmCr4, 4); + PatchInstructionX86 (gPatchSmmCr4, mSmmCr4 & (~CR4_CET_ENABLE), 4); // // Patch GDTR for SMM base relocation @@ -550,6 +553,8 @@ PiCpuSmmEntry ( UINT8 *Stacks; VOID *Registration; UINT32 RegEax; + UINT32 RegEbx; + UINT32 RegEcx; UINT32 RegEdx; UINTN FamilyId; UINTN ModelId; @@ -726,6 +731,32 @@ PiCpuSmmEntry ( } } + DEBUG ((DEBUG_INFO, "PcdCpuSmmCetEnable = %d\n", FeaturePcdGet (PcdCpuSmmCetEnable))); + if (FeaturePcdGet (PcdCpuSmmCetEnable)) { + AsmCpuid (CPUID_EXTENDED_FUNCTION, &RegEax, NULL, NULL, NULL); + if (RegEax > CPUID_EXTENDED_FUNCTION) { + AsmCpuidEx (CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS, CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS_SUB_LEAF_INFO, NULL, NULL, &RegEcx, &RegEdx); + DEBUG ((DEBUG_INFO, "CPUID[7/0] ECX - 0x%08x\n", RegEcx)); + DEBUG ((DEBUG_INFO, " CET_SS - 0x%08x\n", RegEcx & CPUID_CET_SS)); + DEBUG ((DEBUG_INFO, " CET_IBT - 0x%08x\n", RegEdx & CPUID_CET_IBT)); + if ((RegEcx & CPUID_CET_SS) == 0) { + mCetSupported = FALSE; + PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1); + } + if (mCetSupported) { + AsmCpuidEx (CPUID_EXTENDED_STATE, CPUID_EXTENDED_STATE_SUB_LEAF, NULL, &RegEbx, &RegEcx, NULL); + DEBUG ((DEBUG_INFO, "CPUID[D/1] EBX - 0x%08x, ECX - 0x%08x\n", RegEbx, RegEcx)); + AsmCpuidEx (CPUID_EXTENDED_STATE, 11, &RegEax, NULL, &RegEcx, NULL); + DEBUG ((DEBUG_INFO, "CPUID[D/11] EAX - 0x%08x, ECX - 0x%08x\n", RegEax, RegEcx)); + AsmCpuidEx(CPUID_EXTENDED_STATE, 12, &RegEax, NULL, &RegEcx, NULL); + DEBUG ((DEBUG_INFO, "CPUID[D/12] EAX - 0x%08x, ECX - 0x%08x\n", RegEax, RegEcx)); + } + } + } else { + mCetSupported = FALSE; + PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1); + } + // // Compute tile size of buffer required to hold the CPU SMRAM Save State Map, extra CPU // specific context start starts at SMBASE + SMM_PSD_OFFSET, and the SMI entry point. @@ -828,6 +859,7 @@ PiCpuSmmEntry ( // // Allocate SMI stacks for all processors. // + mSmmStackSize = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (PcdGet32 (PcdCpuSmmStackSize))); if (FeaturePcdGet (PcdCpuSmmStackGuard)) { // // 2 more pages is allocated for each processor. @@ -839,15 +871,39 @@ PiCpuSmmEntry ( // | | | | // |<-------------- Processor 0 -------------->| |<-------------- Processor n -------------->| // - mSmmStackSize = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (PcdGet32 (PcdCpuSmmStackSize)) + 2); - Stacks = (UINT8 *) AllocatePages (gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus * (EFI_SIZE_TO_PAGES (PcdGet32 (PcdCpuSmmStackSize)) + 2)); - ASSERT (Stacks != NULL); - mSmmStackArrayBase = (UINTN)Stacks; - mSmmStackArrayEnd = mSmmStackArrayBase + gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus * mSmmStackSize - 1; - } else { - mSmmStackSize = PcdGet32 (PcdCpuSmmStackSize); - Stacks = (UINT8 *) AllocatePages (EFI_SIZE_TO_PAGES (gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus * mSmmStackSize)); - ASSERT (Stacks != NULL); + mSmmStackSize += EFI_PAGES_TO_SIZE (2); + } + + mSmmShadowStackSize = 0; + if (FeaturePcdGet (PcdCpuSmmCetEnable) && mCetSupported) { + // + // Append Shadow Stack after normal stack + // + // |= Stacks + // +--------------------------------------------------+---------------------------------------------------------------+ + // | Known Good Stack | Guard Page | SMM Stack | Known Good Shadow Stack | Guard Page | SMM Shadow Stack | + // +--------------------------------------------------+---------------------------------------------------------------+ + // | |PcdCpuSmmStackSize| |PcdCpuSmmShadowStackSize| + // |<---------------- mSmmStackSize ----------------->|<--------------------- mSmmShadowStackSize ------------------->| + // | | + // |<-------------------------------------------- Processor N ------------------------------------------------------->| + // + mSmmShadowStackSize = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (PcdGet32 (PcdCpuSmmShadowStackSize))); + if (FeaturePcdGet (PcdCpuSmmStackGuard)) { + mSmmShadowStackSize += EFI_PAGES_TO_SIZE (2); + } + } + + Stacks = (UINT8 *) AllocatePages (gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus * (EFI_SIZE_TO_PAGES (mSmmStackSize + mSmmShadowStackSize))); + ASSERT (Stacks != NULL); + mSmmStackArrayBase = (UINTN)Stacks; + mSmmStackArrayEnd = mSmmStackArrayBase + gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus * (mSmmStackSize + mSmmShadowStackSize) - 1; + + DEBUG ((DEBUG_INFO, "Stacks - 0x%x\n", Stacks)); + DEBUG ((DEBUG_INFO, "mSmmStackSize - 0x%x\n", mSmmStackSize)); + DEBUG ((DEBUG_INFO, "PcdCpuSmmStackGuard - 0x%x\n", FeaturePcdGet (PcdCpuSmmStackGuard))); + if (FeaturePcdGet (PcdCpuSmmCetEnable) && mCetSupported) { + DEBUG ((DEBUG_INFO, "mSmmShadowStackSize - 0x%x\n", mSmmShadowStackSize)); } // @@ -887,7 +943,24 @@ PiCpuSmmEntry ( // // Initialize MP globals // - Cr3 = InitializeMpServiceData (Stacks, mSmmStackSize); + Cr3 = InitializeMpServiceData (Stacks, mSmmStackSize, mSmmShadowStackSize); + + if (FeaturePcdGet (PcdCpuSmmCetEnable) && mCetSupported) { + for (Index = 0; Index < gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus; Index++) { + SetShadowStack ( + Cr3, + (EFI_PHYSICAL_ADDRESS)(UINTN)Stacks + mSmmStackSize + (mSmmStackSize + mSmmShadowStackSize) * Index, + mSmmShadowStackSize + ); + if (FeaturePcdGet (PcdCpuSmmStackGuard)) { + SetNotPresentPage ( + Cr3, + (EFI_PHYSICAL_ADDRESS)(UINTN)Stacks + mSmmStackSize + EFI_PAGES_TO_SIZE(1) + (mSmmStackSize + mSmmShadowStackSize) * Index, + EFI_PAGES_TO_SIZE(1) + ); + } + } + } // // Fill in SMM Reserved Regions diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h index 61d4bd3085..84efb22981 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h @@ -1,7 +1,7 @@ /** @file Agent Module to load other modules to deploy SMM Entry Vector for X86 CPU. -Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2009 - 2019, Intel Corporation. All rights reserved.<BR> Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR> This program and the accompanying materials @@ -64,6 +64,51 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. #include "CpuService.h" #include "SmmProfile.h" +// +// CET definition +// +#define CPUID_CET_SS BIT7 +#define CPUID_CET_IBT BIT20 + +#define CR4_CET_ENABLE BIT23 + +#define MSR_IA32_S_CET 0x6A2 +#define MSR_IA32_PL0_SSP 0x6A4 +#define MSR_IA32_INTERRUPT_SSP_TABLE_ADDR 0x6A8 + +typedef union { + struct { + // enable shadow stacks + UINT32 SH_STK_ENP:1; + // enable the WRSS{D,Q}W instructions. + UINT32 WR_SHSTK_EN:1; + // enable tracking of indirect call/jmp targets to be ENDBRANCH instruction. + UINT32 ENDBR_EN:1; + // enable legacy compatibility treatment for indirect call/jmp tracking. + UINT32 LEG_IW_EN:1; + // enable use of no-track prefix on indirect call/jmp. + UINT32 NO_TRACK_EN:1; + // disable suppression of CET indirect branch tracking on legacy compatibility. + UINT32 SUPPRESS_DIS:1; + UINT32 RSVD:4; + // indirect branch tracking is suppressed. + // This bit can be written to 1 only if TRACKER is written as IDLE. + UINT32 SUPPRESS:1; + // Value of the endbranch state machine + // Values: IDLE (0), WAIT_FOR_ENDBRANCH(1). + UINT32 TRACKER:1; + // linear address of a bitmap in memory indicating valid + // pages as target of CALL/JMP_indirect that do not land on ENDBRANCH when CET is enabled + // and not suppressed. Valid when ENDBR_EN is 1. Must be machine canonical when written on + // parts that support 64 bit mode. On parts that do not support 64 bit mode, the bits 63:32 are + // reserved and must be 0. This value is extended by 12 bits at the low end to form the base address + // (this automatically aligns the address on a 4-Kbyte boundary). + UINT32 EB_LEG_BITMAP_BASE_low:12; + UINT32 EB_LEG_BITMAP_BASE_high:32; + } Bits; + UINT64 Uint64; +} MSR_IA32_CET; + // // MSRs required for configuration of SMM Code Access Check // @@ -127,9 +172,11 @@ typedef struct { // Size of Task-State Segment defined in IA32 Manual // #define TSS_SIZE 104 +#define EXCEPTION_TSS_SIZE (TSS_SIZE + 4) // Add 4 bytes SSP #define TSS_X64_IST1_OFFSET 36 #define TSS_IA32_CR3_OFFSET 28 #define TSS_IA32_ESP_OFFSET 56 +#define TSS_IA32_SSP_OFFSET 104 #define CR0_WP BIT16 @@ -305,6 +352,8 @@ X86_ASSEMBLY_PATCH_LABEL gPatchSmmCr3; extern UINT32 mSmmCr4; X86_ASSEMBLY_PATCH_LABEL gPatchSmmCr4; X86_ASSEMBLY_PATCH_LABEL gPatchSmmInitStack; +X86_ASSEMBLY_PATCH_LABEL mPatchCetSupported; +extern BOOLEAN mCetSupported; /** Semaphore operation for all processor relocate SMMBase. @@ -418,14 +467,16 @@ Gen4GPageTable ( /** Initialize global data for MP synchronization. - @param Stacks Base address of SMI stack buffer for all processors. - @param StackSize Stack size for each processor in SMM. + @param Stacks Base address of SMI stack buffer for all processors. + @param StackSize Stack size for each processor in SMM. + @param ShadowStackSize Shadow Stack size for each processor in SMM. **/ UINT32 InitializeMpServiceData ( IN VOID *Stacks, - IN UINTN StackSize + IN UINTN StackSize, + IN UINTN ShadowStackSize ); /** @@ -1036,6 +1087,50 @@ TransferApToSafeState ( IN UINTN NumberToFinishAddress ); +/** + Set ShadowStack memory. + + @param[in] Cr3 The page table base address. + @param[in] BaseAddress The physical address that is the start address of a memory region. + @param[in] Length The size in bytes of the memory region. + + @retval EFI_SUCCESS The shadow stack memory is set. +**/ +EFI_STATUS +SetShadowStack ( + IN UINTN Cr3, + IN EFI_PHYSICAL_ADDRESS BaseAddress, + IN UINT64 Length + ); + +/** + Set not present memory. + + @param[in] Cr3 The page table base address. + @param[in] BaseAddress The physical address that is the start address of a memory region. + @param[in] Length The size in bytes of the memory region. + + @retval EFI_SUCCESS The not present memory is set. +**/ +EFI_STATUS +SetNotPresentPage ( + IN UINTN Cr3, + IN EFI_PHYSICAL_ADDRESS BaseAddress, + IN UINT64 Length + ); + +/** + Initialize the shadow stack related data structure. + + @param CpuIndex The index of CPU. + @param ShadowStack The bottom of the shadow stack for this CPU. +**/ +VOID +InitShadowStack ( + IN UINTN CpuIndex, + IN VOID *ShadowStack + ); + /** This function set given attributes of the memory region specified by BaseAddress and Length. diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf index 666f851faf..105fdd316a 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf @@ -4,7 +4,7 @@ # This SMM driver performs SMM initialization, deploy SMM Entry Vector, # provides CPU specific services in SMM. # -# Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR> +# Copyright (c) 2009 - 2019, Intel Corporation. All rights reserved.<BR> # Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR> # # This program and the accompanying materials @@ -57,6 +57,7 @@ Ia32/SmiEntry.nasm Ia32/SmiException.nasm Ia32/MpFuncs.nasm + Ia32/Cet.nasm [Sources.X64] X64/Semaphore.c @@ -68,6 +69,7 @@ X64/SmiEntry.nasm X64/SmiException.nasm X64/MpFuncs.nasm + X64/Cet.nasm [Packages] MdePkg/MdePkg.dec @@ -124,6 +126,7 @@ gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmProfileEnable ## CONSUMES gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmProfileRingBuffer ## CONSUMES gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmFeatureControlMsrLock ## CONSUMES + gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmCetEnable [Pcd] gUefiCpuPkgTokenSpaceGuid.PcdCpuMaxLogicalProcessorNumber ## SOMETIMES_CONSUMES @@ -135,6 +138,7 @@ gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmCodeAccessCheckEnable ## CONSUMES gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmSyncMode ## CONSUMES gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmStaticPageTable ## CONSUMES + gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmShadowStackSize ## SOMETIMES_CONSUMES gEfiMdeModulePkgTokenSpaceGuid.PcdAcpiS3Enable ## CONSUMES gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask ## CONSUMES gEfiMdeModulePkgTokenSpaceGuid.PcdNullPointerDetectionPropertyMask ## CONSUMES diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c index 684b14dc28..48f5f954cb 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c @@ -1,6 +1,6 @@ /** @file -Copyright (c) 2016 - 2018, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2016 - 2019, 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 @@ -38,6 +38,23 @@ PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = { {Page1G, SIZE_1GB, PAGING_1G_ADDRESS_MASK_64}, }; +UINTN mInternalGr3; + +/** + Set the internal page table base address. + If it is non zero, further MemoryAttribute modification will be on this page table. + If it is zero, further MemoryAttribute modification will be on real page table. + + @param Cr3 page table base. +**/ +VOID +SetPageTableBase ( + IN UINTN Cr3 + ) +{ + mInternalGr3 = Cr3; +} + /** Return page table base. @@ -48,6 +65,9 @@ GetPageTableBase ( VOID ) { + if (mInternalGr3 != 0) { + return mInternalGr3; + } return (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64); } @@ -220,6 +240,17 @@ ConvertPageEntryAttribute ( if ((Attributes & EFI_MEMORY_RO) != 0) { if (IsSet) { NewPageEntry &= ~(UINT64)IA32_PG_RW; + if (mInternalGr3 != 0) { + // Environment setup + // ReadOnly page need set Dirty bit for shadow stack + NewPageEntry |= IA32_PG_D; + // Clear user bit for supervisor shadow stack + NewPageEntry &= ~(UINT64)IA32_PG_U; + } else { + // Runtime update + // Clear dirty bit for non shadow stack, to protect RO page. + NewPageEntry &= ~(UINT64)IA32_PG_D; + } } else { NewPageEntry |= IA32_PG_RW; } @@ -661,7 +692,59 @@ SmmClearMemoryAttributes ( return SmmClearMemoryAttributesEx (BaseAddress, Length, Attributes, NULL); } +/** + Set ShadowStack memory. + + @param[in] Cr3 The page table base address. + @param[in] BaseAddress The physical address that is the start address of a memory region. + @param[in] Length The size in bytes of the memory region. + + @retval EFI_SUCCESS The shadow stack memory is set. +**/ +EFI_STATUS +SetShadowStack ( + IN UINTN Cr3, + IN EFI_PHYSICAL_ADDRESS BaseAddress, + IN UINT64 Length + ) +{ + EFI_STATUS Status; + + SetPageTableBase (Cr3); + + Status = SmmSetMemoryAttributes (BaseAddress, Length, EFI_MEMORY_RO); + + SetPageTableBase (0); + + return Status; +} + +/** + Set not present memory. + + @param[in] Cr3 The page table base address. + @param[in] BaseAddress The physical address that is the start address of a memory region. + @param[in] Length The size in bytes of the memory region. + @retval EFI_SUCCESS The not present memory is set. +**/ +EFI_STATUS +SetNotPresentPage ( + IN UINTN Cr3, + IN EFI_PHYSICAL_ADDRESS BaseAddress, + IN UINT64 Length + ) +{ + EFI_STATUS Status; + + SetPageTableBase (Cr3); + + Status = SmmSetMemoryAttributes (BaseAddress, Length, EFI_MEMORY_RP); + + SetPageTableBase (0); + + return Status; +} /** Retrieves a pointer to the system configuration table from the SMM System Table diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c index 91b8e7ddb9..4881011ca2 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.c @@ -1,7 +1,7 @@ /** @file Enable SMM profile. -Copyright (c) 2012 - 2018, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2012 - 2019, Intel Corporation. All rights reserved.<BR> Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR> This program and the accompanying materials @@ -927,7 +927,7 @@ InitSmmProfileInternal ( } /** - Check if XD feature is supported by a processor. + Check if feature is supported by a processor. **/ VOID @@ -936,9 +936,23 @@ CheckFeatureSupported ( ) { UINT32 RegEax; + UINT32 RegEcx; UINT32 RegEdx; MSR_IA32_MISC_ENABLE_REGISTER MiscEnableMsr; + if (FeaturePcdGet (PcdCpuSmmCetEnable) && mCetSupported) { + AsmCpuid (CPUID_EXTENDED_FUNCTION, &RegEax, NULL, NULL, NULL); + if (RegEax <= CPUID_EXTENDED_FUNCTION) { + mCetSupported = FALSE; + PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1); + } + AsmCpuidEx (CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS, CPUID_STRUCTURED_EXTENDED_FEATURE_FLAGS_SUB_LEAF_INFO, NULL, NULL, &RegEcx, NULL); + if ((RegEcx & CPUID_CET_SS) == 0) { + mCetSupported = FALSE; + PatchInstructionX86 (mPatchCetSupported, mCetSupported, 1); + } + } + if (mXdSupported) { AsmCpuid (CPUID_EXTENDED_FUNCTION, &RegEax, NULL, NULL, NULL); if (RegEax <= CPUID_EXTENDED_FUNCTION) { diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.h b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.h index c2a48235ab..a2db0d9eb9 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.h +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmProfile.h @@ -1,7 +1,7 @@ /** @file SMM profile header file. -Copyright (c) 2012 - 2016, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2012 - 2019, 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 @@ -88,7 +88,7 @@ PageFaultIdtHandlerSmmProfile ( /** - Check if XD feature is supported by a processor. + Check if feature is supported by a processor. **/ VOID diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c b/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c index 5c2eb9ab6a..8f34875e17 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c @@ -1,7 +1,7 @@ /** @file Provides services to access SMRAM Save State Map -Copyright (c) 2010 - 2017, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2010 - 2019, 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 @@ -714,6 +714,8 @@ InstallSmiHandler ( return; } + InitShadowStack (CpuIndex, (VOID *)((UINTN)SmiStack + StackSize)); + // // Initialize values in template before copy // diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/Cet.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/Cet.nasm new file mode 100644 index 0000000000..13efc0314d --- /dev/null +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/Cet.nasm @@ -0,0 +1,38 @@ +;------------------------------------------------------------------------------ ; +; Copyright (c) 2019, 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 +; http://opensource.org/licenses/bsd-license.php. +; +; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, +; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. +; +;------------------------------------------------------------------------------- + +DEFAULT REL +SECTION .text + +global ASM_PFX(DisableCet) +ASM_PFX(DisableCet): + + ; Skip the pushed data for call + mov rax, 1 + DB 0xF3, 0x48, 0x0F, 0xAE, 0xE8 ; INCSSP RAX + + mov rax, cr4 + btr eax, 23 ; clear CET + mov cr4, rax + ret + +global ASM_PFX(EnableCet) +ASM_PFX(EnableCet): + + mov rax, cr4 + bts eax, 23 ; set CET + mov cr4, rax + + ; use jmp to skip the check for ret + pop rax + jmp rax + diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c index 117502dafa..2c77cb47a4 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/PageTbl.c @@ -1,7 +1,7 @@ /** @file Page Fault (#PF) handler for X64 processors -Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2009 - 2019, Intel Corporation. All rights reserved.<BR> Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR> This program and the accompanying materials @@ -23,6 +23,24 @@ LIST_ENTRY mPagePool = INITIALIZE_LIST_HEAD_VARIABLE (m BOOLEAN m1GPageTableSupport = FALSE; BOOLEAN mCpuSmmStaticPageTable; +/** + Disable CET. +**/ +VOID +EFIAPI +DisableCet ( + VOID + ); + +/** + Enable CET. +**/ +VOID +EFIAPI +EnableCet ( + VOID + ); + /** Check if 1-GByte pages is supported by processor or not. @@ -821,6 +839,7 @@ SmiPFHandler ( DumpCpuContext (InterruptType, SystemContext); DEBUG ((DEBUG_ERROR, "Do not support address 0x%lx by processor!\n", PFAddress)); CpuDeadLoop (); + goto Exit; } // @@ -855,6 +874,7 @@ SmiPFHandler ( } } CpuDeadLoop (); + goto Exit; } // @@ -869,6 +889,7 @@ SmiPFHandler ( DumpModuleInfoByIp (*(UINTN *)(UINTN)SystemContext.SystemContextX64->Rsp); ); CpuDeadLoop (); + goto Exit; } // @@ -888,6 +909,7 @@ SmiPFHandler ( } CpuDeadLoop (); + goto Exit; } if (mCpuSmmStaticPageTable && IsSmmCommBufferForbiddenAddress (PFAddress)) { @@ -897,6 +919,7 @@ SmiPFHandler ( DumpModuleInfoByIp ((UINTN)SystemContext.SystemContextX64->Rip); ); CpuDeadLoop (); + goto Exit; } } @@ -930,6 +953,7 @@ SetPageTableAttributes ( UINT64 *L4PageTable; BOOLEAN IsSplitted; BOOLEAN PageTableSplitted; + BOOLEAN CetEnabled; // // Don't do this if @@ -961,6 +985,13 @@ SetPageTableAttributes ( // Disable write protection, because we need mark page table to be write protected. // We need *write* page table memory, to mark itself to be *read only*. // + CetEnabled = ((AsmReadCr4() & CR4_CET_ENABLE) != 0) ? TRUE : FALSE; + if (CetEnabled) { + // + // CET must be disabled if WP is disabled. + // + DisableCet(); + } AsmWriteCr0 (AsmReadCr0() & ~CR0_WP); do { @@ -1013,6 +1044,12 @@ SetPageTableAttributes ( // Enable write protection, after page table updated. // AsmWriteCr0 (AsmReadCr0() | CR0_WP); + if (CetEnabled) { + // + // re-enable CET. + // + EnableCet(); + } return ; } diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm index 807b309b27..76b7ec1dc5 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm @@ -1,5 +1,5 @@ ;------------------------------------------------------------------------------ ; -; Copyright (c) 2016 - 2018, Intel Corporation. All rights reserved.<BR> +; Copyright (c) 2016 - 2019, 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 @@ -24,6 +24,20 @@ ; Variables referrenced by C code ; +%define MSR_IA32_S_CET 0x6A2 +%define MSR_IA32_CET_SH_STK_EN 0x1 +%define MSR_IA32_CET_WR_SHSTK_EN 0x2 +%define MSR_IA32_CET_ENDBR_EN 0x4 +%define MSR_IA32_CET_LEG_IW_EN 0x8 +%define MSR_IA32_CET_NO_TRACK_EN 0x10 +%define MSR_IA32_CET_SUPPRESS_DIS 0x20 +%define MSR_IA32_CET_SUPPRESS 0x400 +%define MSR_IA32_CET_TRACKER 0x800 +%define MSR_IA32_PL0_SSP 0x6A4 +%define MSR_IA32_INTERRUPT_SSP_TABLE_ADDR 0x6A8 + +%define CR4_CET 0x800000 + %define MSR_IA32_MISC_ENABLE 0x1A0 %define MSR_EFER 0xc0000080 %define MSR_EFER_XD 0x800 @@ -63,6 +77,12 @@ global ASM_PFX(gPatchSmiCr3) global ASM_PFX(gcSmiHandlerTemplate) global ASM_PFX(gcSmiHandlerSize) +extern ASM_PFX(mCetSupported) +global ASM_PFX(mPatchCetSupported) +global ASM_PFX(mPatchCetPl0Ssp) +global ASM_PFX(mPatchCetInterruptSsp) +global ASM_PFX(mPatchCetInterruptSspTable) + DEFAULT REL SECTION .text @@ -174,8 +194,71 @@ SmiHandlerIdtrAbsAddr: mov ax, [rbx + DSC_SS] mov ss, eax -_SmiHandler: - mov rbx, [rsp + 0x8] ; rcx <- CpuIndex + mov rbx, [rsp + 0x8] ; rbx <- CpuIndex + +; enable CET if supported + mov al, strict byte 1 ; source operand may be patched +ASM_PFX(mPatchCetSupported): + cmp al, 0 + jz CetDone + + mov ecx, MSR_IA32_S_CET + rdmsr + push rdx + push rax + + mov ecx, MSR_IA32_PL0_SSP + rdmsr + push rdx + push rax + + mov ecx, MSR_IA32_INTERRUPT_SSP_TABLE_ADDR + rdmsr + push rdx + push rax + + mov ecx, MSR_IA32_S_CET + mov eax, MSR_IA32_CET_SH_STK_EN + xor edx, edx + wrmsr + + mov ecx, MSR_IA32_PL0_SSP + mov eax, strict dword 0 ; source operand will be patched +ASM_PFX(mPatchCetPl0Ssp): + xor edx, edx + wrmsr + mov rcx, cr0 + btr ecx, 16 ; clear WP + mov cr0, rcx + mov [eax], eax ; reload SSP, and clear busyflag. + xor ecx, ecx + mov [eax + 4], ecx + + mov ecx, MSR_IA32_INTERRUPT_SSP_TABLE_ADDR + mov eax, strict dword 0 ; source operand will be patched +ASM_PFX(mPatchCetInterruptSspTable): + xor edx, edx + wrmsr + + mov eax, strict dword 0 ; source operand will be patched +ASM_PFX(mPatchCetInterruptSsp): + cmp eax, 0 + jz CetInterruptDone + mov [eax], eax ; reload SSP, and clear busyflag. + xor ecx, ecx + mov [eax + 4], ecx +CetInterruptDone: + + mov rcx, cr0 + bts ecx, 16 ; set WP + mov cr0, rcx + + mov eax, 0x668 | CR4_CET + mov cr4, rax + + DB 0xF3, 0x0F, 0x01, 0xE8 ; SETSSBSY + +CetDone: ; ; Save FP registers @@ -209,6 +292,31 @@ CpuSmmDebugExitAbsAddr: add rsp, 0x200 + mov rax, strict qword 0 ; mov rax, ASM_PFX(mCetSupported) +mCetSupportedAbsAddr: + mov al, [rax] + cmp al, 0 + jz CetDone2 + + mov eax, 0x668 + mov cr4, rax ; disable CET + + mov ecx, MSR_IA32_INTERRUPT_SSP_TABLE_ADDR + pop rax + pop rdx + wrmsr + + mov ecx, MSR_IA32_PL0_SSP + pop rax + pop rdx + wrmsr + + mov ecx, MSR_IA32_S_CET + pop rax + pop rdx + wrmsr +CetDone2: + mov rax, strict qword 0 ; lea rax, [ASM_PFX(mXdSupported)] mXdSupportedAbsAddr: mov al, [rax] @@ -223,6 +331,7 @@ mXdSupportedAbsAddr: wrmsr .1: + StuffRsb64 rsm @@ -257,4 +366,8 @@ ASM_PFX(PiSmmCpuSmiEntryFixupAddress): lea rax, [ASM_PFX(mXdSupported)] lea rcx, [mXdSupportedAbsAddr] mov qword [rcx - 8], rax + + lea rax, [ASM_PFX(mCetSupported)] + lea rcx, [mCetSupportedAbsAddr] + mov qword [rcx - 8], rax ret diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c index 89b3f2b725..43687d1884 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c @@ -1,7 +1,7 @@ /** @file SMM CPU misc functions for x64 arch specific. -Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR> +Copyright (c) 2015 - 2019, 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 @@ -17,6 +17,18 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. EFI_PHYSICAL_ADDRESS mGdtBuffer; UINTN mGdtBufferSize; +extern BOOLEAN mCetSupported; +extern UINTN mSmmShadowStackSize; + +X86_ASSEMBLY_PATCH_LABEL mPatchCetPl0Ssp; +X86_ASSEMBLY_PATCH_LABEL mPatchCetInterruptSsp; +X86_ASSEMBLY_PATCH_LABEL mPatchCetInterruptSspTable; +UINT32 mCetPl0Ssp; +UINT32 mCetInterruptSsp; +UINT32 mCetInterruptSspTable; + +UINTN mSmmInterruptSspTables; + /** Initialize IDT for SMM Stack Guard. @@ -153,3 +165,47 @@ TransferApToSafeState ( ASSERT (FALSE); } +/** + Initialize the shadow stack related data structure. + + @param CpuIndex The index of CPU. + @param ShadowStack The bottom of the shadow stack for this CPU. +**/ +VOID +InitShadowStack ( + IN UINTN CpuIndex, + IN VOID *ShadowStack + ) +{ + UINTN SmmShadowStackSize; + UINT64 *InterruptSspTable; + + if (FeaturePcdGet (PcdCpuSmmCetEnable) && mCetSupported) { + SmmShadowStackSize = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (PcdGet32 (PcdCpuSmmShadowStackSize))); + if (FeaturePcdGet (PcdCpuSmmStackGuard)) { + SmmShadowStackSize += EFI_PAGES_TO_SIZE (2); + } + mCetPl0Ssp = (UINT32)((UINTN)ShadowStack + SmmShadowStackSize - sizeof(UINT64)); + PatchInstructionX86 (mPatchCetPl0Ssp, mCetPl0Ssp, 4); + DEBUG ((DEBUG_INFO, "mCetPl0Ssp - 0x%x\n", mCetPl0Ssp)); + DEBUG ((DEBUG_INFO, "ShadowStack - 0x%x\n", ShadowStack)); + DEBUG ((DEBUG_INFO, " SmmShadowStackSize - 0x%x\n", SmmShadowStackSize)); + + if (FeaturePcdGet (PcdCpuSmmStackGuard)) { + if (mSmmInterruptSspTables == 0) { + mSmmInterruptSspTables = (UINTN)AllocateZeroPool(sizeof(UINT64) * 8 * gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus); + ASSERT (mSmmInterruptSspTables != 0); + DEBUG ((DEBUG_INFO, "mSmmInterruptSspTables - 0x%x\n", mSmmInterruptSspTables)); + } + mCetInterruptSsp = (UINT32)((UINTN)ShadowStack + EFI_PAGES_TO_SIZE(1) - sizeof(UINT64)); + mCetInterruptSspTable = (UINT32)(UINTN)(mSmmInterruptSspTables + sizeof(UINT64) * 8 * CpuIndex); + InterruptSspTable = (UINT64 *)(UINTN)mCetInterruptSspTable; + InterruptSspTable[1] = mCetInterruptSsp; + PatchInstructionX86 (mPatchCetInterruptSsp, mCetInterruptSsp, 4); + PatchInstructionX86 (mPatchCetInterruptSspTable, mCetInterruptSspTable, 4); + DEBUG ((DEBUG_INFO, "mCetInterruptSsp - 0x%x\n", mCetInterruptSsp)); + DEBUG ((DEBUG_INFO, "mCetInterruptSspTable - 0x%x\n", mCetInterruptSspTable)); + } + } +} + diff --git a/UefiCpuPkg/UefiCpuPkg.dec b/UefiCpuPkg/UefiCpuPkg.dec index 69d777aa65..c76f63bf6f 100644 --- a/UefiCpuPkg/UefiCpuPkg.dec +++ b/UefiCpuPkg/UefiCpuPkg.dec @@ -1,7 +1,7 @@ ## @file UefiCpuPkg.dec # This Package provides UEFI compatible CPU modules and libraries. # -# Copyright (c) 2007 - 2017, Intel Corporation. All rights reserved.<BR> +# Copyright (c) 2007 - 2019, 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. @@ -138,6 +138,13 @@ # @Prompt Lock SMM Feature Control MSR. gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmFeatureControlMsrLock|TRUE|BOOLEAN|0x3213210B + ## Indicates if SMM CET will be enabled. + # If enabled, stack smash in SMM can be caught, preventing chaotic consequences.<BR><BR> + # TRUE - SMM CET will be enabled.<BR> + # FALSE - SMM CET will be disabled.<BR> + # @Prompt Enable SMM Stack Guard. + gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmCetEnable|TRUE|BOOLEAN|0x1000001D + [PcdsFixedAtBuild] ## List of exception vectors which need switching stack. # This PCD will only take into effect if PcdCpuStackGuard is enabled. @@ -177,6 +184,10 @@ # @Prompt Processor stack size in SMM. gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmStackSize|0x2000|UINT32|0x32132105 + ## Specifies shadow stack size in bytes for each processor in SMM. + # @Prompt Processor shadow stack size in SMM. + gUefiCpuPkgTokenSpaceGuid.PcdCpuSmmShadowStackSize|0x2000|UINT32|0x3213210E + ## Indicates if SMM Code Access Check is enabled. # If enabled, the SMM handler cannot execute the code outside SMM regions. # This PCD is suggested to TRUE in production image.<BR><BR> -- 2.19.2.windows.1 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel