UefiCpuPkg/CpuMpPei: support stack guard feature

This feature is the same as Stack Guard enabled in driver CpuDxe but
applies to PEI phase. Due to the specialty in PEI module dispatching,
this driver is changed to do the actual initialization in notify
callback of event gEfiPeiMemoryDiscoveredPpiGuid. This can let the
stack guard apply to as most PEI drivers as possible.

To let Stack Guard work, some simple page table management code are
introduced to setup Guard page at base of stack for each processor.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: "Ware, Ryan R" <ryan.r.ware@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>

1 files changed, 257 insertions, 14 deletions

diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.c b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
index 7c94d5a6d7..cd9a6ae3ba 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.c
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
@@ -409,25 +409,227 @@ PeiWhoAmI (
 }

 

 /**

-  The Entry point of the MP CPU PEIM.

+  Get GDT register value.

 

-  This function will wakeup APs and collect CPU AP count and install the

-  Mp Service Ppi.

+  This function is mainly for AP purpose because AP may have different GDT

+  table than BSP.

 

-  @param  FileHandle    Handle of the file being invoked.

-  @param  PeiServices   Describes the list of possible PEI Services.

+  @param[in,out] Buffer  The pointer to private data buffer.

 

-  @retval EFI_SUCCESS   MpServicePpi is installed successfully.

+**/

+VOID

+EFIAPI

+GetGdtr (

+  IN OUT VOID *Buffer

+  )

+{

+  AsmReadGdtr ((IA32_DESCRIPTOR *)Buffer);

+}

+

+/**

+  Initializes CPU exceptions handlers for the sake of stack switch requirement.

+

+  This function is a wrapper of InitializeCpuExceptionHandlersEx. It's mainly

+  for the sake of AP's init because of EFI_AP_PROCEDURE API requirement.

+

+  @param[in,out] Buffer  The pointer to private data buffer.

 

 **/

-EFI_STATUS

+VOID

 EFIAPI

-CpuMpPeimInit (

-  IN       EFI_PEI_FILE_HANDLE  FileHandle,

+InitializeExceptionStackSwitchHandlers (

+  IN OUT VOID *Buffer

+  )

+{

+  CPU_EXCEPTION_INIT_DATA           *EssData;

+  IA32_DESCRIPTOR                   Idtr;

+  EFI_STATUS                        Status;

+

+  EssData = Buffer;

+  //

+  // We don't plan to replace IDT table with a new one, but we should not assume

+  // the AP's IDT is the same as BSP's IDT either.

+  //

+  AsmReadIdtr (&Idtr);

+  EssData->Ia32.IdtTable = (VOID *)Idtr.Base;

+  EssData->Ia32.IdtTableSize = Idtr.Limit + 1;

+  Status = InitializeCpuExceptionHandlersEx (NULL, EssData);

+  ASSERT_EFI_ERROR (Status);

+}

+

+/**

+  Initializes MP exceptions handlers for the sake of stack switch requirement.

+

+  This function will allocate required resources required to setup stack switch

+  and pass them through CPU_EXCEPTION_INIT_DATA to each logic processor.

+

+**/

+VOID

+InitializeMpExceptionStackSwitchHandlers (

+  VOID

+  )

+{

+  EFI_STATUS                      Status;

+  UINTN                           Index;

+  UINTN                           Bsp;

+  UINTN                           ExceptionNumber;

+  UINTN                           OldGdtSize;

+  UINTN                           NewGdtSize;

+  UINTN                           NewStackSize;

+  IA32_DESCRIPTOR                 Gdtr;

+  CPU_EXCEPTION_INIT_DATA         EssData;

+  UINT8                           *GdtBuffer;

+  UINT8                           *StackTop;

+  UINTN                           NumberOfProcessors;

+

+  if (!PcdGetBool (PcdCpuStackGuard)) {

+    return;

+  }

+

+  MpInitLibGetNumberOfProcessors(&NumberOfProcessors, NULL);

+  MpInitLibWhoAmI (&Bsp);

+

+  ExceptionNumber = FixedPcdGetSize (PcdCpuStackSwitchExceptionList);

+  NewStackSize = FixedPcdGet32 (PcdCpuKnownGoodStackSize) * ExceptionNumber;

+

+  Status = PeiServicesAllocatePool (

+             NewStackSize * NumberOfProcessors,

+             (VOID **)&StackTop

+             );

+  ASSERT(StackTop != NULL);

+  if (EFI_ERROR (Status)) {

+    ASSERT_EFI_ERROR (Status);

+    return;

+  }

+  StackTop += NewStackSize  * NumberOfProcessors;

+

+  //

+  // The default exception handlers must have been initialized. Let's just skip

+  // it in this method.

+  //

+  EssData.Ia32.Revision = CPU_EXCEPTION_INIT_DATA_REV;

+  EssData.Ia32.InitDefaultHandlers = FALSE;

+

+  EssData.Ia32.StackSwitchExceptions = FixedPcdGetPtr(PcdCpuStackSwitchExceptionList);

+  EssData.Ia32.StackSwitchExceptionNumber = ExceptionNumber;

+  EssData.Ia32.KnownGoodStackSize = FixedPcdGet32(PcdCpuKnownGoodStackSize);

+

+  //

+  // Initialize Gdtr to suppress incorrect compiler/analyzer warnings.

+  //

+  Gdtr.Base = 0;

+  Gdtr.Limit = 0;

+  for (Index = 0; Index < NumberOfProcessors; ++Index) {

+    //

+    // To support stack switch, we need to re-construct GDT but not IDT.

+    //

+    if (Index == Bsp) {

+      GetGdtr(&Gdtr);

+    } else {

+      //

+      // AP might have different size of GDT from BSP.

+      //

+      MpInitLibStartupThisAP (GetGdtr, Index, NULL, 0, (VOID *)&Gdtr, NULL);

+    }

+

+    //

+    // X64 needs only one TSS of current task working for all exceptions

+    // because of its IST feature. IA32 needs one TSS for each exception

+    // in addition to current task. Since AP is not supposed to allocate

+    // memory, we have to do it in BSP. To simplify the code, we allocate

+    // memory for IA32 case to cover both IA32 and X64 exception stack

+    // switch.

+    //

+    // Layout of memory to allocate for each processor:

+    //    --------------------------------

+    //    |            Alignment         |  (just in case)

+    //    --------------------------------

+    //    |                              |

+    //    |        Original GDT          |

+    //    |                              |

+    //    --------------------------------

+    //    |    Current task descriptor   |

+    //    --------------------------------

+    //    |                              |

+    //    |  Exception task descriptors  |  X ExceptionNumber

+    //    |                              |

+    //    --------------------------------

+    //    |  Current task-state segment  |

+    //    --------------------------------

+    //    |                              |

+    //    | Exception task-state segment |  X ExceptionNumber

+    //    |                              |

+    //    --------------------------------

+    //

+    OldGdtSize = Gdtr.Limit + 1;

+    EssData.Ia32.ExceptionTssDescSize = sizeof (IA32_TSS_DESCRIPTOR) *

+                                        (ExceptionNumber + 1);

+    EssData.Ia32.ExceptionTssSize = sizeof (IA32_TASK_STATE_SEGMENT) *

+                                    (ExceptionNumber + 1);

+    NewGdtSize = sizeof (IA32_TSS_DESCRIPTOR) +

+                 OldGdtSize +

+                 EssData.Ia32.ExceptionTssDescSize +

+                 EssData.Ia32.ExceptionTssSize;

+

+    Status = PeiServicesAllocatePool (

+               NewGdtSize,

+               (VOID **)&GdtBuffer

+               );

+    ASSERT (GdtBuffer != NULL);

+    if (EFI_ERROR (Status)) {

+      ASSERT_EFI_ERROR (Status);

+      return;

+    }

+

+    //

+    // Make sure GDT table alignment

+    //

+    EssData.Ia32.GdtTable = ALIGN_POINTER(GdtBuffer, sizeof (IA32_TSS_DESCRIPTOR));

+    NewGdtSize -= ((UINT8 *)EssData.Ia32.GdtTable - GdtBuffer);

+    EssData.Ia32.GdtTableSize = NewGdtSize;

+

+    EssData.Ia32.ExceptionTssDesc = ((UINT8 *)EssData.Ia32.GdtTable + OldGdtSize);

+    EssData.Ia32.ExceptionTss = ((UINT8 *)EssData.Ia32.GdtTable + OldGdtSize +

+                                 EssData.Ia32.ExceptionTssDescSize);

+

+    EssData.Ia32.KnownGoodStackTop = (UINTN)StackTop;

+    DEBUG ((DEBUG_INFO,

+            "Exception stack top[cpu%lu]: 0x%lX\n",

+            (UINT64)(UINTN)Index,

+            (UINT64)(UINTN)StackTop));

+

+    if (Index == Bsp) {

+      InitializeExceptionStackSwitchHandlers (&EssData);

+    } else {

+      MpInitLibStartupThisAP (

+        InitializeExceptionStackSwitchHandlers,

+        Index,

+        NULL,

+        0,

+        (VOID *)&EssData,

+        NULL

+        );

+    }

+

+    StackTop  -= NewStackSize;

+  }

+}

+

+/**

+  Initializes MP and exceptions handlers.

+

+  @param  PeiServices                The pointer to the PEI Services Table.

+

+  @retval EFI_SUCCESS     MP was successfully initialized.

+  @retval others          Error occurred in MP initialization.

+

+**/

+EFI_STATUS

+InitializeCpuMpWorker (

   IN CONST EFI_PEI_SERVICES     **PeiServices

   )

 {

-  EFI_STATUS           Status;

+  EFI_STATUS                      Status;

   EFI_VECTOR_HANDOFF_INFO         *VectorInfo;

   EFI_PEI_VECTOR_HANDOFF_INFO_PPI *VectorHandoffInfoPpi;

 

@@ -444,14 +646,24 @@ CpuMpPeimInit (
   if (Status == EFI_SUCCESS) {

     VectorInfo = VectorHandoffInfoPpi->Info;

   }

-  Status = InitializeCpuExceptionHandlers (VectorInfo);

-  ASSERT_EFI_ERROR (Status);

 

   //

-  // Wakeup APs to do initialization

+  // Initialize default handlers

   //

+  Status = InitializeCpuExceptionHandlers (VectorInfo);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

   Status = MpInitLibInitialize ();

-  ASSERT_EFI_ERROR (Status);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

+  //

+  // Special initialization for the sake of Stack Guard

+  //

+  InitializeMpExceptionStackSwitchHandlers ();

 

   //

   // Update and publish CPU BIST information

@@ -466,3 +678,34 @@ CpuMpPeimInit (
 

   return Status;

 }

+

+/**

+  The Entry point of the MP CPU PEIM.

+

+  This function will wakeup APs and collect CPU AP count and install the

+  Mp Service Ppi.

+

+  @param  FileHandle    Handle of the file being invoked.

+  @param  PeiServices   Describes the list of possible PEI Services.

+

+  @retval EFI_SUCCESS   MpServicePpi is installed successfully.

+

+**/

+EFI_STATUS

+EFIAPI

+CpuMpPeimInit (

+  IN       EFI_PEI_FILE_HANDLE  FileHandle,

+  IN CONST EFI_PEI_SERVICES     **PeiServices

+  )

+{

+  EFI_STATUS           Status;

+

+  //

+  // For the sake of special initialization needing to be done right after

+  // memory discovery.

+  //

+  Status = PeiServicesNotifyPpi (&mPostMemNotifyList[0]);

+  ASSERT_EFI_ERROR (Status);

+

+  return Status;

+}