EmbeddedPkg: Add option to disable EFI Memory Attribute Protocol

Introduce a driver that allows users to disable the EFI Memory Attribute
protocol through an HII setup option, in order to work around a broken
version of rhboot's shim used in some distros (e.g. CentOS Stream 9)
which incorrectly invokes the protocol and results in a Synchronous
Exception.

Default is enabled, which can also be overridden at build time by
changing `gEmbeddedTokenSpaceGuid.PcdMemoryAttributeEnabledDefault`.

It is only applicable to ARM64 and there isn't any other technical
reason for disabling this security feature.

See:
- https://github.com/microsoft/mu_silicon_arm_tiano/issues/124
- https://edk2.groups.io/g/devel/topic/99631663
- https://github.com/tianocore/edk2/pull/5840

Signed-off-by: Mario Bălănică <mariobalanica02@gmail.com>

8 files changed, 360 insertions, 0 deletions

diff --git a/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.c b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.c
new file mode 100644
index 0000000000..7a0156ddbf
--- /dev/null
+++ b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.c
@@ -0,0 +1,197 @@
+/** @file

+

+  Copyright (c) 2023-2024, Mario Bălănică <mariobalanica02@gmail.com>

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+

+**/

+

+#include <Uefi.h>

+#include <Library/DebugLib.h>

+#include <Library/DevicePathLib.h>

+#include <Library/HiiLib.h>

+#include <Library/UefiBootServicesTableLib.h>

+#include <Library/UefiRuntimeServicesTableLib.h>

+

+#include "MemoryAttributeManagerDxe.h"

+

+extern UINT8  MemoryAttributeManagerDxeHiiBin[];

+extern UINT8  MemoryAttributeManagerDxeStrings[];

+

+typedef struct {

+  VENDOR_DEVICE_PATH          VendorDevicePath;

+  EFI_DEVICE_PATH_PROTOCOL    End;

+} HII_VENDOR_DEVICE_PATH;

+

+STATIC HII_VENDOR_DEVICE_PATH  mVendorDevicePath = {

+  {

+    {

+      HARDWARE_DEVICE_PATH,

+      HW_VENDOR_DP,

+      {

+        (UINT8)(sizeof (VENDOR_DEVICE_PATH)),

+        (UINT8)((sizeof (VENDOR_DEVICE_PATH)) >> 8)

+      }

+    },

+    MEMORY_ATTRIBUTE_MANAGER_FORMSET_GUID

+  },

+  {

+    END_DEVICE_PATH_TYPE,

+    END_ENTIRE_DEVICE_PATH_SUBTYPE,

+    {

+      (UINT8)(END_DEVICE_PATH_LENGTH),

+      (UINT8)((END_DEVICE_PATH_LENGTH) >> 8)

+    }

+  }

+};

+

+/**

+  Installs HII page for user configuration.

+

+  @retval EFI_SUCCESS        The operation completed successfully.

+

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+InstallHiiPages (

+  VOID

+  )

+{

+  EFI_STATUS      Status;

+  EFI_HII_HANDLE  HiiHandle;

+  EFI_HANDLE      DriverHandle;

+

+  DriverHandle = NULL;

+  Status       = gBS->InstallMultipleProtocolInterfaces (

+                        &DriverHandle,

+                        &gEfiDevicePathProtocolGuid,

+                        &mVendorDevicePath,

+                        NULL

+                        );

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

+  HiiHandle = HiiAddPackages (

+                &gMemoryAttributeManagerFormSetGuid,

+                DriverHandle,

+                MemoryAttributeManagerDxeStrings,

+                MemoryAttributeManagerDxeHiiBin,

+                NULL

+                );

+

+  if (HiiHandle == NULL) {

+    gBS->UninstallMultipleProtocolInterfaces (

+           DriverHandle,

+           &gEfiDevicePathProtocolGuid,

+           &mVendorDevicePath,

+           NULL

+           );

+    return EFI_OUT_OF_RESOURCES;

+  }

+

+  return EFI_SUCCESS;

+}

+

+/**

+  This function uninstalls the EFI_MEMORY_ATTRIBUTE_PROTOCOL

+  from CpuDxe's handle.

+**/

+STATIC

+VOID

+UninstallEfiMemoryAttributeProtocol (

+  VOID

+  )

+{

+  EFI_STATUS  Status;

+  EFI_HANDLE  Handle;

+  UINTN       Size;

+  VOID        *MemoryAttributeProtocol;

+

+  Size   = sizeof (Handle);

+  Status = gBS->LocateHandle (

+                  ByProtocol,

+                  &gEfiMemoryAttributeProtocolGuid,

+                  NULL,

+                  &Size,

+                  &Handle

+                  );

+  if (EFI_ERROR (Status)) {

+    ASSERT (Status == EFI_NOT_FOUND);

+    return;

+  }

+

+  Status = gBS->HandleProtocol (

+                  Handle,

+                  &gEfiMemoryAttributeProtocolGuid,

+                  &MemoryAttributeProtocol

+                  );

+  ASSERT_EFI_ERROR (Status);

+  if (EFI_ERROR (Status)) {

+    return;

+  }

+

+  Status = gBS->UninstallProtocolInterface (

+                  Handle,

+                  &gEfiMemoryAttributeProtocolGuid,

+                  MemoryAttributeProtocol

+                  );

+  ASSERT_EFI_ERROR (Status);

+  if (EFI_ERROR (Status)) {

+    return;

+  }

+

+  DEBUG ((

+    DEBUG_INFO,

+    "EFI Memory Attribute Protocol disabled due to user/platform preference!\n"

+    ));

+}

+

+/**

+  The entry point for MemoryAttributeManagerDxe driver.

+

+  @param[in] ImageHandle     The image handle of the driver.

+  @param[in] SystemTable     The system table.

+

+  @retval EFI_SUCCESS        The operation completed successfully.

+

+**/

+EFI_STATUS

+EFIAPI

+MemoryAttributeManagerInitialize (

+  IN  EFI_HANDLE        ImageHandle,

+  IN  EFI_SYSTEM_TABLE  *SystemTable

+  )

+{

+  EFI_STATUS                              Status;

+  UINTN                                   Size;

+  MEMORY_ATTRIBUTE_MANAGER_VARSTORE_DATA  Config;

+

+  Config.Enabled = PROTOCOL_ENABLED_DEFAULT;

+

+  Size   = sizeof (MEMORY_ATTRIBUTE_MANAGER_VARSTORE_DATA);

+  Status = gRT->GetVariable (

+                  MEMORY_ATTRIBUTE_MANAGER_DATA_VAR_NAME,

+                  &gMemoryAttributeManagerFormSetGuid,

+                  NULL,

+                  &Size,

+                  &Config

+                  );

+  if (EFI_ERROR (Status)) {

+    Status = gRT->SetVariable (

+                    MEMORY_ATTRIBUTE_MANAGER_DATA_VAR_NAME,

+                    &gMemoryAttributeManagerFormSetGuid,

+                    EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,

+                    Size,

+                    &Config

+                    );

+    ASSERT_EFI_ERROR (Status);

+  }

+

+  if (!Config.Enabled) {

+    UninstallEfiMemoryAttributeProtocol ();

+  }

+

+  return InstallHiiPages ();

+}

diff --git a/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.h b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.h
new file mode 100644
index 0000000000..a027f3e4b6
--- /dev/null
+++ b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.h
@@ -0,0 +1,22 @@
+/** @file

+

+  Copyright (c) 2023-2024, Mario Bălănică <mariobalanica02@gmail.com>

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+

+**/

+

+#ifndef MEMORY_ATTRIBUTE_MANAGER_DXE_H_

+#define MEMORY_ATTRIBUTE_MANAGER_DXE_H_

+

+#include <Guid/MemoryAttributeManagerFormSet.h>

+

+#define PROTOCOL_ENABLED_DEFAULT  FixedPcdGetBool(PcdMemoryAttributeEnabledDefault)

+

+#define MEMORY_ATTRIBUTE_MANAGER_DATA_VAR_NAME  L"MemoryAttributeManagerData"

+

+typedef struct {

+  BOOLEAN    Enabled;

+} MEMORY_ATTRIBUTE_MANAGER_VARSTORE_DATA;

+

+#endif // __MEMORY_ATTRIBUTE_MANAGER_DXE_H__

diff --git a/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.inf b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.inf
new file mode 100644
index 0000000000..b55639cd71
--- /dev/null
+++ b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.inf
@@ -0,0 +1,62 @@
+## @file

+#  EFI Memory Attribute Protocol state manager

+#

+#  This driver allows users to disable the EFI Memory Attribute protocol

+#  through an HII setup option, in order to work around a broken version

+#  of rhboot's shim used in some distros (e.g. CentOS Stream 9) which

+#  incorrectly invokes the protocol and results in a Synchronous Exception.

+#

+#  It is only applicable to ARM64 and there isn't any other technical

+#  reason for disabling this security feature.

+#

+#  See:

+#    - https://github.com/microsoft/mu_silicon_arm_tiano/issues/124

+#    - https://edk2.groups.io/g/devel/topic/99631663

+#    - https://github.com/tianocore/edk2/pull/5840

+#

+#  Copyright (c) 2023-2024, Mario Bălănică <mariobalanica02@gmail.com>

+#

+#  SPDX-License-Identifier: BSD-2-Clause-Patent

+#

+##

+

+[Defines]

+  INF_VERSION                    = 0x0001001B

+  BASE_NAME                      = MemoryAttributeManagerDxe

+  FILE_GUID                      = 5319346b-66ad-433a-9a91-f7fc286bc9a1

+  MODULE_TYPE                    = DXE_DRIVER

+  VERSION_STRING                 = 1.0

+  ENTRY_POINT                    = MemoryAttributeManagerInitialize

+

+[Sources]

+  MemoryAttributeManagerDxe.c

+  MemoryAttributeManagerDxe.h

+  MemoryAttributeManagerDxeHii.uni

+  MemoryAttributeManagerDxeHii.vfr

+

+[Packages]

+  EmbeddedPkg/EmbeddedPkg.dec

+  MdePkg/MdePkg.dec

+  MdeModulePkg/MdeModulePkg.dec

+

+[LibraryClasses]

+  DebugLib

+  DevicePathLib

+  HiiLib

+  UefiBootServicesTableLib

+  UefiRuntimeServicesTableLib

+  UefiDriverEntryPoint

+

+[Guids]

+  gMemoryAttributeManagerFormSetGuid

+

+[Protocols]

+  gEfiMemoryAttributeProtocolGuid

+

+[Pcd]

+  gEmbeddedTokenSpaceGuid.PcdMemoryAttributeEnabledDefault

+

+[Depex]

+  gEfiVariableArchProtocolGuid        AND

+  gEfiVariableWriteArchProtocolGuid   AND

+  gEfiMemoryAttributeProtocolGuid

diff --git a/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxeHii.uni b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxeHii.uni
new file mode 100644
index 0000000000..8537824b1f
--- /dev/null
+++ b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxeHii.uni
@@ -0,0 +1,17 @@
+/** @file

+

+  Copyright (c) 2023-2024, Mario Bălănică <mariobalanica02@gmail.com>

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+

+**/

+

+#langdef en-US  "English"

+

+#string STR_NULL_STRING                                    #language en-US ""

+

+#string STR_FORM_SET_TITLE                                 #language en-US "EFI Memory Attribute Protocol"

+#string STR_FORM_SET_TITLE_HELP                            #language en-US "Configure the state of the EFI Memory Attribute Protocol.\n\n"

+                                                                           "Some old OS loader versions (e.g. as found in CentOS Stream 9) do not properly support the protocol and may cause a Synchronous Exception. This security feature can be disabled to work around the issue; otherwise it should be kept enabled."

+

+#string STR_ENABLE_PROTOCOL_PROMPT                         #language en-US "Enable Protocol"

diff --git a/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxeHii.vfr b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxeHii.vfr
new file mode 100644
index 0000000000..a303426e3c
--- /dev/null
+++ b/EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxeHii.vfr
@@ -0,0 +1,35 @@
+/** @file

+

+  Copyright (c) 2023-2024, Mario Bălănică <mariobalanica02@gmail.com>

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+

+**/

+

+#include <Uefi/UefiMultiPhase.h>

+#include <Guid/HiiPlatformSetupFormset.h>

+

+#include "MemoryAttributeManagerDxe.h"

+

+formset

+  guid      = MEMORY_ATTRIBUTE_MANAGER_FORMSET_GUID,

+  title     = STRING_TOKEN(STR_FORM_SET_TITLE),

+  help      = STRING_TOKEN(STR_FORM_SET_TITLE_HELP),

+  classguid = EFI_HII_PLATFORM_SETUP_FORMSET_GUID,

+

+  efivarstore MEMORY_ATTRIBUTE_MANAGER_VARSTORE_DATA,

+  attribute = EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_NON_VOLATILE,

+  name  = MemoryAttributeManagerData,

+  guid  = MEMORY_ATTRIBUTE_MANAGER_FORMSET_GUID;

+

+  form formid = 1,

+    title  = STRING_TOKEN(STR_FORM_SET_TITLE);

+

+    checkbox varid = MemoryAttributeManagerData.Enabled,

+      prompt      = STRING_TOKEN(STR_ENABLE_PROTOCOL_PROMPT),

+      help        = STRING_TOKEN(STR_NULL_STRING),

+      flags       = CHECKBOX_DEFAULT | CHECKBOX_DEFAULT_MFG | RESET_REQUIRED,

+      default     = PROTOCOL_ENABLED_DEFAULT,

+    endcheckbox;

+  endform;

+endformset;

diff --git a/EmbeddedPkg/EmbeddedPkg.dec b/EmbeddedPkg/EmbeddedPkg.dec
index 5dfbbc2933..3497fa1df7 100644
--- a/EmbeddedPkg/EmbeddedPkg.dec
+++ b/EmbeddedPkg/EmbeddedPkg.dec
@@ -73,6 +73,9 @@
   ## Include/Guid/NvVarStoreFormatted.h

   gEdkiiNvVarStoreFormattedGuid = { 0xd1a86e3f, 0x0707, 0x4c35, { 0x83, 0xcd, 0xdc, 0x2c, 0x29, 0xc8, 0x91, 0xa3 } }

 

+  # Include/Guid/MemoryAttributeManagerFormSet.h

+  gMemoryAttributeManagerFormSetGuid = { 0xefab3427, 0x4793, 0x4e9e, { 0xaa, 0x29, 0x88, 0x0c, 0x9a, 0x77, 0x5b, 0x5f } }

+

 [Protocols.common]

   gHardwareInterruptProtocolGuid =  { 0x2890B3EA, 0x053D, 0x1643, { 0xAD, 0x0C, 0xD6, 0x48, 0x08, 0xDA, 0x3F, 0xF1 } }

   gHardwareInterrupt2ProtocolGuid = { 0x32898322, 0x2da1, 0x474a, { 0xba, 0xaa, 0xf3, 0xf7, 0xcf, 0x56, 0x94, 0x70 } }

@@ -192,3 +195,8 @@
   # Expected Overflow Android Kernel Command Line Characters

   #

   gEmbeddedTokenSpaceGuid.PcdAndroidKernelCommandLineOverflow|0|UINT32|0x000005C

+

+  #

+  # EFI Memory Attribute Protocol default enable state

+  #

+  gEmbeddedTokenSpaceGuid.PcdMemoryAttributeEnabledDefault|TRUE|BOOLEAN|0x00000060

diff --git a/EmbeddedPkg/EmbeddedPkg.dsc b/EmbeddedPkg/EmbeddedPkg.dsc
index e9062cacbb..ef66aea29d 100644
--- a/EmbeddedPkg/EmbeddedPkg.dsc
+++ b/EmbeddedPkg/EmbeddedPkg.dsc
@@ -239,6 +239,8 @@
   EmbeddedPkg/Drivers/DtPlatformDxe/DtPlatformDxe.inf

   EmbeddedPkg/Drivers/FdtClientDxe/FdtClientDxe.inf

 

+  EmbeddedPkg/Drivers/MemoryAttributeManagerDxe/MemoryAttributeManagerDxe.inf

+

   EmbeddedPkg/Drivers/NonCoherentIoMmuDxe/NonCoherentIoMmuDxe.inf {

     <LibraryClasses>

       DmaLib|EmbeddedPkg/Library/NonCoherentDmaLib/NonCoherentDmaLib.inf

diff --git a/EmbeddedPkg/Include/Guid/MemoryAttributeManagerFormSet.h b/EmbeddedPkg/Include/Guid/MemoryAttributeManagerFormSet.h
new file mode 100644
index 0000000000..2efdf03216
--- /dev/null
+++ b/EmbeddedPkg/Include/Guid/MemoryAttributeManagerFormSet.h
@@ -0,0 +1,17 @@
+/** @file

+

+  Copyright (c) 2023-2024, Mario Bălănică <mariobalanica02@gmail.com>

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+

+**/

+

+#ifndef MEMORY_ATTRIBUTE_MANAGER_FORMSET_H_

+#define MEMORY_ATTRIBUTE_MANAGER_FORMSET_H_

+

+#define MEMORY_ATTRIBUTE_MANAGER_FORMSET_GUID \

+  { 0xefab3427, 0x4793, 0x4e9e, { 0xaa, 0x29, 0x88, 0x0c, 0x9a, 0x77, 0x5b, 0x5f } }

+

+extern EFI_GUID  gMemoryAttributeManagerFormSetGuid;

+

+#endif // __MEMORY_ATTRIBUTE_MANAGER_FORMSET_H__