From: Michael Kubacki <michael.a.kubacki@intel.com>
REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1614
Moves the GDT to permanent memory in a memory discovered
callback. This is done to ensure the GDT authenticated in
pre-memory is not fetched from outside a verified location
after the permanent memory transition.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Signed-off-by: Michael Kubacki <michael.a.kubacki@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
---
UefiCpuPkg/CpuMpPei/CpuMpPei.inf | 1 +
UefiCpuPkg/CpuMpPei/CpuMpPei.h | 12 +++++++++++
UefiCpuPkg/CpuMpPei/CpuMpPei.c | 37 ++++++++++++++++++++++++++++++++
UefiCpuPkg/CpuMpPei/CpuPaging.c | 12 +++++++++--
4 files changed, 60 insertions(+), 2 deletions(-)
diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.inf b/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
index caead3ce34d4..f4d11b861f77 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
@@ -63,6 +63,7 @@ [Pcd]
gUefiCpuPkgTokenSpaceGuid.PcdCpuStackSwitchExceptionList ## SOMETIMES_CONSUMES
gUefiCpuPkgTokenSpaceGuid.PcdCpuKnownGoodStackSize ## SOMETIMES_CONSUMES
gUefiCpuPkgTokenSpaceGuid.PcdCpuApStackSize ## SOMETIMES_CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdMigrateTemporaryRamFirmwareVolumes ## CONSUMES
[Depex]
TRUE
diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.h b/UefiCpuPkg/CpuMpPei/CpuMpPei.h
index 7d5c527d6006..309478cbe14c 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.h
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.h
@@ -397,6 +397,18 @@ SecPlatformInformation2 (
OUT EFI_SEC_PLATFORM_INFORMATION_RECORD2 *PlatformInformationRecord2
);
+/**
+ Migrates the Global Descriptor Table (GDT) to permanent memory.
+
+ @retval EFI_SUCCESS The GDT was migrated successfully.
+ @retval EFI_OUT_OF_RESOURCES The GDT could not be migrated due to lack of available memory.
+
+**/
+EFI_STATUS
+MigrateGdt (
+ VOID
+ );
+
/**
Initializes MP and exceptions handlers.
diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.c b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
index 07ccbe7c6a91..d07540cf7471 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.c
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
@@ -429,6 +429,43 @@ GetGdtr (
AsmReadGdtr ((IA32_DESCRIPTOR *)Buffer);
}
+/**
+ Migrates the Global Descriptor Table (GDT) to permanent memory.
+
+ @retval EFI_SUCCESS The GDT was migrated successfully.
+ @retval EFI_OUT_OF_RESOURCES The GDT could not be migrated due to lack of available memory.
+
+**/
+EFI_STATUS
+MigrateGdt (
+ VOID
+ )
+{
+ EFI_STATUS Status;
+ UINTN GdtBufferSize;
+ IA32_DESCRIPTOR Gdtr;
+ VOID *GdtBuffer;
+
+ AsmReadGdtr ((IA32_DESCRIPTOR *) &Gdtr);
+ GdtBufferSize = sizeof (IA32_SEGMENT_DESCRIPTOR) -1 + Gdtr.Limit + 1;
+
+ Status = PeiServicesAllocatePool (
+ GdtBufferSize,
+ &GdtBuffer
+ );
+ ASSERT (GdtBuffer != NULL);
+ if (EFI_ERROR (Status)) {
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ GdtBuffer = ALIGN_POINTER (GdtBuffer, sizeof (IA32_SEGMENT_DESCRIPTOR));
+ CopyMem (GdtBuffer, (VOID *) Gdtr.Base, Gdtr.Limit + 1);
+ Gdtr.Base = (UINTN) GdtBuffer;
+ AsmWriteGdtr (&Gdtr);
+
+ return EFI_SUCCESS;
+}
+
/**
Initializes CPU exceptions handlers for the sake of stack switch requirement.
diff --git a/UefiCpuPkg/CpuMpPei/CpuPaging.c b/UefiCpuPkg/CpuMpPei/CpuPaging.c
index a462e7ee1e38..3bf0574b34c6 100644
--- a/UefiCpuPkg/CpuMpPei/CpuPaging.c
+++ b/UefiCpuPkg/CpuMpPei/CpuPaging.c
@@ -602,8 +602,16 @@ MemoryDiscoveredPpiNotifyCallback (
IN VOID *Ppi
)
{
- EFI_STATUS Status;
- BOOLEAN InitStackGuard;
+ EFI_STATUS Status;
+ BOOLEAN InitStackGuard;
+ BOOLEAN InterruptState;
+
+ if (PcdGetBool (PcdMigrateTemporaryRamFirmwareVolumes)) {
+ InterruptState = SaveAndDisableInterrupts ();
+ Status = MigrateGdt ();
+ ASSERT_EFI_ERROR (Status);
+ SetInterruptState (InterruptState);
+ }
//
// Paging must be setup first. Otherwise the exception TSS setup during MP
--
2.25.1.windows.1
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Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Regards,
Jian
> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Guomin
> Jiang
> Sent: Monday, July 20, 2020 7:30 PM
> To: devel@edk2.groups.io
> Cc: Michael Kubacki <michael.a.kubacki@intel.com>; Dong, Eric
> <eric.dong@intel.com>; Ni, Ray <ray.ni@intel.com>; Laszlo Ersek
> <lersek@redhat.com>; Kumar, Rahul1 <rahul1.kumar@intel.com>
> Subject: [edk2-devel] [PATCH v6 03/10] UefiCpuPkg/CpuMpPei: Add GDT
> migration support (CVE-2019-11098)
>
> From: Michael Kubacki <michael.a.kubacki@intel.com>
>
> REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1614
>
> Moves the GDT to permanent memory in a memory discovered
> callback. This is done to ensure the GDT authenticated in
> pre-memory is not fetched from outside a verified location
> after the permanent memory transition.
>
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Rahul Kumar <rahul1.kumar@intel.com>
> Signed-off-by: Michael Kubacki <michael.a.kubacki@intel.com>
> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
> ---
> UefiCpuPkg/CpuMpPei/CpuMpPei.inf | 1 +
> UefiCpuPkg/CpuMpPei/CpuMpPei.h | 12 +++++++++++
> UefiCpuPkg/CpuMpPei/CpuMpPei.c | 37
> ++++++++++++++++++++++++++++++++
> UefiCpuPkg/CpuMpPei/CpuPaging.c | 12 +++++++++--
> 4 files changed, 60 insertions(+), 2 deletions(-)
>
> diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
> b/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
> index caead3ce34d4..f4d11b861f77 100644
> --- a/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
> +++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
> @@ -63,6 +63,7 @@ [Pcd]
> gUefiCpuPkgTokenSpaceGuid.PcdCpuStackSwitchExceptionList ##
> SOMETIMES_CONSUMES
> gUefiCpuPkgTokenSpaceGuid.PcdCpuKnownGoodStackSize ##
> SOMETIMES_CONSUMES
> gUefiCpuPkgTokenSpaceGuid.PcdCpuApStackSize ##
> SOMETIMES_CONSUMES
> +
> gEfiMdeModulePkgTokenSpaceGuid.PcdMigrateTemporaryRamFirmwareVolum
> es ## CONSUMES
>
> [Depex]
> TRUE
> diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.h
> b/UefiCpuPkg/CpuMpPei/CpuMpPei.h
> index 7d5c527d6006..309478cbe14c 100644
> --- a/UefiCpuPkg/CpuMpPei/CpuMpPei.h
> +++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.h
> @@ -397,6 +397,18 @@ SecPlatformInformation2 (
> OUT EFI_SEC_PLATFORM_INFORMATION_RECORD2
> *PlatformInformationRecord2
> );
>
> +/**
> + Migrates the Global Descriptor Table (GDT) to permanent memory.
> +
> + @retval EFI_SUCCESS The GDT was migrated successfully.
> + @retval EFI_OUT_OF_RESOURCES The GDT could not be migrated due to
> lack of available memory.
> +
> +**/
> +EFI_STATUS
> +MigrateGdt (
> + VOID
> + );
> +
> /**
> Initializes MP and exceptions handlers.
>
> diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.c
> b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
> index 07ccbe7c6a91..d07540cf7471 100644
> --- a/UefiCpuPkg/CpuMpPei/CpuMpPei.c
> +++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
> @@ -429,6 +429,43 @@ GetGdtr (
> AsmReadGdtr ((IA32_DESCRIPTOR *)Buffer);
> }
>
> +/**
> + Migrates the Global Descriptor Table (GDT) to permanent memory.
> +
> + @retval EFI_SUCCESS The GDT was migrated successfully.
> + @retval EFI_OUT_OF_RESOURCES The GDT could not be migrated due to
> lack of available memory.
> +
> +**/
> +EFI_STATUS
> +MigrateGdt (
> + VOID
> + )
> +{
> + EFI_STATUS Status;
> + UINTN GdtBufferSize;
> + IA32_DESCRIPTOR Gdtr;
> + VOID *GdtBuffer;
> +
> + AsmReadGdtr ((IA32_DESCRIPTOR *) &Gdtr);
> + GdtBufferSize = sizeof (IA32_SEGMENT_DESCRIPTOR) -1 + Gdtr.Limit + 1;
> +
> + Status = PeiServicesAllocatePool (
> + GdtBufferSize,
> + &GdtBuffer
> + );
> + ASSERT (GdtBuffer != NULL);
> + if (EFI_ERROR (Status)) {
> + return EFI_OUT_OF_RESOURCES;
> + }
> +
> + GdtBuffer = ALIGN_POINTER (GdtBuffer, sizeof
> (IA32_SEGMENT_DESCRIPTOR));
> + CopyMem (GdtBuffer, (VOID *) Gdtr.Base, Gdtr.Limit + 1);
> + Gdtr.Base = (UINTN) GdtBuffer;
> + AsmWriteGdtr (&Gdtr);
> +
> + return EFI_SUCCESS;
> +}
> +
> /**
> Initializes CPU exceptions handlers for the sake of stack switch requirement.
>
> diff --git a/UefiCpuPkg/CpuMpPei/CpuPaging.c
> b/UefiCpuPkg/CpuMpPei/CpuPaging.c
> index a462e7ee1e38..3bf0574b34c6 100644
> --- a/UefiCpuPkg/CpuMpPei/CpuPaging.c
> +++ b/UefiCpuPkg/CpuMpPei/CpuPaging.c
> @@ -602,8 +602,16 @@ MemoryDiscoveredPpiNotifyCallback (
> IN VOID *Ppi
> )
> {
> - EFI_STATUS Status;
> - BOOLEAN InitStackGuard;
> + EFI_STATUS Status;
> + BOOLEAN InitStackGuard;
> + BOOLEAN InterruptState;
> +
> + if (PcdGetBool (PcdMigrateTemporaryRamFirmwareVolumes)) {
> + InterruptState = SaveAndDisableInterrupts ();
> + Status = MigrateGdt ();
> + ASSERT_EFI_ERROR (Status);
> + SetInterruptState (InterruptState);
> + }
>
> //
> // Paging must be setup first. Otherwise the exception TSS setup during MP
> --
> 2.25.1.windows.1
>
>
>
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