[edk2-devel] [PATCH v3 11/26] OvmfPkg: Apply Memory Protections via SetMemoryProtectionsLib

["Taylor Beebe" <taylor.d.beebe@gmail.com>]

Use SetMemoryProtectionsLib to set the memory protections for
the platform in both normal and PEI-less boot. The protections
set are equivalent to the PCD settings and the ability to set
NxForStack via QemuCfg is preserved. Once the transition to use
SetMemoryProtectionsLib and GetMemoryProtectionsLib is complete
in the rest of EDK2, the mechanics of setting protections in
OvmfPkg will be updated and the memory protection PCDs will
be deleted.

Signed-off-by: Taylor Beebe <taylor.d.beebe@gmail.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
---
 OvmfPkg/Library/PeilessStartupLib/PeilessStartup.c      | 15 +++++++++++++--
 OvmfPkg/PlatformPei/Platform.c                          | 15 +++++++++++++--
 OvmfPkg/Library/PeilessStartupLib/PeilessStartupLib.inf |  3 +++
 OvmfPkg/PlatformPei/PlatformPei.inf                     |  1 +
 4 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/OvmfPkg/Library/PeilessStartupLib/PeilessStartup.c b/OvmfPkg/Library/PeilessStartupLib/PeilessStartup.c
index 1632a2317718..cf645aad3246 100644
--- a/OvmfPkg/Library/PeilessStartupLib/PeilessStartup.c
+++ b/OvmfPkg/Library/PeilessStartupLib/PeilessStartup.c
@@ -14,10 +14,13 @@
 #include <Protocol/DebugSupport.h>
 #include <Library/TdxLib.h>
 #include <IndustryStandard/Tdx.h>
+#include <Library/PcdLib.h>
 #include <Library/PrePiLib.h>
 #include <Library/PeilessStartupLib.h>
 #include <Library/PlatformInitLib.h>
 #include <Library/TdxHelperLib.h>
+#include <Library/SetMemoryProtectionsLib.h>
+#include <Library/QemuFwCfgSimpleParserLib.h>
 #include <ConfidentialComputingGuestAttr.h>
 #include <Guid/MemoryTypeInformation.h>
 #include <OvmfPlatforms.h>
@@ -42,7 +45,9 @@ InitializePlatform (
   EFI_HOB_PLATFORM_INFO  *PlatformInfoHob
   )
 {
-  VOID  *VariableStore;
+  VOID                            *VariableStore;
+  DXE_MEMORY_PROTECTION_SETTINGS  DxeSettings;
+  MM_MEMORY_PROTECTION_SETTINGS   MmSettings;
 
   DEBUG ((DEBUG_INFO, "InitializePlatform in Pei-less boot\n"));
   PlatformDebugDumpCmos ();
@@ -104,7 +109,13 @@ InitializePlatform (
 
   PlatformMemMapInitialization (PlatformInfoHob);
 
-  PlatformNoexecDxeInitialization (PlatformInfoHob);
+  DxeSettings                                 = DxeMemoryProtectionProfiles[DxeMemoryProtectionSettingsPcd].Settings;
+  MmSettings                                  = MmMemoryProtectionProfiles[MmMemoryProtectionSettingsPcd].Settings;
+  DxeSettings.StackExecutionProtectionEnabled = PcdGetBool (PcdSetNxForStack);
+  QemuFwCfgParseBool ("opt/ovmf/PcdSetNxForStack", &DxeSettings.StackExecutionProtectionEnabled);
+
+  SetDxeMemoryProtectionSettings (&DxeSettings, DxeMemoryProtectionSettingsPcd);
+  SetMmMemoryProtectionSettings (&MmSettings, MmMemoryProtectionSettingsPcd);
 
   if (TdIsEnabled ()) {
     PlatformInfoHob->PcdConfidentialComputingGuestAttr = CCAttrIntelTdx;
diff --git a/OvmfPkg/PlatformPei/Platform.c b/OvmfPkg/PlatformPei/Platform.c
index f5dc41c3a8c4..bcd8d3a1be14 100644
--- a/OvmfPkg/PlatformPei/Platform.c
+++ b/OvmfPkg/PlatformPei/Platform.c
@@ -38,6 +38,7 @@
 #include <IndustryStandard/QemuCpuHotplug.h>
 #include <Library/MemEncryptSevLib.h>
 #include <OvmfPlatforms.h>
+#include <Library/SetMemoryProtectionsLib.h>
 
 #include "Platform.h"
 
@@ -304,8 +305,10 @@ InitializePlatform (
   IN CONST EFI_PEI_SERVICES     **PeiServices
   )
 {
-  EFI_HOB_PLATFORM_INFO  *PlatformInfoHob;
-  EFI_STATUS             Status;
+  EFI_HOB_PLATFORM_INFO           *PlatformInfoHob;
+  EFI_STATUS                      Status;
+  DXE_MEMORY_PROTECTION_SETTINGS  DxeSettings;
+  MM_MEMORY_PROTECTION_SETTINGS   MmSettings;
 
   DEBUG ((DEBUG_INFO, "Platform PEIM Loaded\n"));
   PlatformInfoHob = BuildPlatformInfoHob ();
@@ -342,6 +345,14 @@ InitializePlatform (
 
   PublishPeiMemory (PlatformInfoHob);
 
+  DxeSettings                                 = DxeMemoryProtectionProfiles[DxeMemoryProtectionSettingsPcd].Settings;
+  MmSettings                                  = MmMemoryProtectionProfiles[MmMemoryProtectionSettingsPcd].Settings;
+  DxeSettings.StackExecutionProtectionEnabled = PcdGetBool (PcdSetNxForStack);
+  QemuFwCfgParseBool ("opt/ovmf/PcdSetNxForStack", &DxeSettings.StackExecutionProtectionEnabled);
+
+  SetDxeMemoryProtectionSettings (&DxeSettings, DxeMemoryProtectionSettingsPcd);
+  SetMmMemoryProtectionSettings (&MmSettings, MmMemoryProtectionSettingsPcd);
+
   PlatformQemuUc32BaseInitialization (PlatformInfoHob);
 
   InitializeRamRegions (PlatformInfoHob);
diff --git a/OvmfPkg/Library/PeilessStartupLib/PeilessStartupLib.inf b/OvmfPkg/Library/PeilessStartupLib/PeilessStartupLib.inf
index 585d50463748..f0a8a5a56df4 100644
--- a/OvmfPkg/Library/PeilessStartupLib/PeilessStartupLib.inf
+++ b/OvmfPkg/Library/PeilessStartupLib/PeilessStartupLib.inf
@@ -56,6 +56,8 @@ [LibraryClasses]
   PrePiLib
   QemuFwCfgLib
   PlatformInitLib
+  SetMemoryProtectionsLib
+  QemuFwCfgSimpleParserLib
 
 [Guids]
   gEfiHobMemoryAllocModuleGuid
@@ -81,6 +83,7 @@ [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdImageProtectionPolicy       ## SOMETIMES_CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdNullPointerDetectionPropertyMask    ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdSetNxForStack                       ## CONSUMES
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfDxeMemFvBase
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfDxeMemFvSize
   gUefiOvmfPkgTokenSpaceGuid.PcdSecureBootSupported
diff --git a/OvmfPkg/PlatformPei/PlatformPei.inf b/OvmfPkg/PlatformPei/PlatformPei.inf
index 3934aeed9514..6b8442d12b2c 100644
--- a/OvmfPkg/PlatformPei/PlatformPei.inf
+++ b/OvmfPkg/PlatformPei/PlatformPei.inf
@@ -65,6 +65,7 @@ [LibraryClasses]
   PcdLib
   CcExitLib
   PlatformInitLib
+  SetMemoryProtectionsLib
 
 [Pcd]
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfPeiMemFvBase
-- 
2.42.0.windows.1



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