StandaloneMmPkg/StandaloneMmCoreEntryPoint: permit the use of TE images

TE images take up less space when using 4 KB section alignment, since
the FFS/FV generation code optimizes away the redundant, nested padding.
This saves 4 KB of space, which is a worthwhile improvement for code
that executes in place in secure context.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Achin Gupta <achin.gupta@arm.com>

1 files changed, 46 insertions, 61 deletions

diff --git a/StandaloneMmPkg/Library/StandaloneMmCoreEntryPoint/AArch64/SetPermissions.c b/StandaloneMmPkg/Library/StandaloneMmCoreEntryPoint/AArch64/SetPermissions.c
index 3ca7f6660f..90299ebbaf 100644
--- a/StandaloneMmPkg/Library/StandaloneMmCoreEntryPoint/AArch64/SetPermissions.c
+++ b/StandaloneMmPkg/Library/StandaloneMmCoreEntryPoint/AArch64/SetPermissions.c
@@ -143,9 +143,12 @@ LocateStandaloneMmCorePeCoffData (
 

   Status = FfsFindSectionData (EFI_SECTION_PE32, FileHeader, TeData, TeDataSize);

   if (EFI_ERROR (Status)) {

-      DEBUG ((DEBUG_ERROR, "Unable to locate Standalone MM Section data - 0x%x\n",

-              Status));

-    return Status;

+    Status = FfsFindSectionData (EFI_SECTION_TE, FileHeader, TeData, TeDataSize);

+    if (EFI_ERROR (Status)) {

+        DEBUG ((DEBUG_ERROR, "Unable to locate Standalone MM Section data - %r\n",

+                Status));

+      return Status;

+    }

   }

 

   DEBUG ((DEBUG_INFO, "Found Standalone MM PE data - 0x%x\n", *TeData));

@@ -155,10 +158,9 @@ LocateStandaloneMmCorePeCoffData (
 STATIC

 EFI_STATUS

 GetPeCoffSectionInformation (

-  IN  CONST PE_COFF_LOADER_IMAGE_CONTEXT      *ImageContext,

-  IN  OUT   PE_COFF_LOADER_IMAGE_CONTEXT      *TmpContext,

-  IN  OUT   UINT32                            *SectionHeaderOffset,

-  IN  OUT   UINT16                            *NumberOfSections

+  IN  OUT   PE_COFF_LOADER_IMAGE_CONTEXT      *ImageContext,

+      OUT   UINT32                            *SectionHeaderOffset,

+      OUT   UINT16                            *NumberOfSections

   )

 {

   RETURN_STATUS                         Status;

@@ -168,44 +170,29 @@ GetPeCoffSectionInformation (
   UINTN                                 ReadSize;

 

   ASSERT (ImageContext != NULL);

-  ASSERT (TmpContext != NULL);

   ASSERT (SectionHeaderOffset != NULL);

   ASSERT (NumberOfSections != NULL);

 

-  //

-  // We need to copy ImageContext since PeCoffLoaderGetImageInfo ()

-  // will mangle the ImageAddress field

-  //

-  CopyMem (TmpContext, ImageContext, sizeof (*TmpContext));

-

-  if (TmpContext->PeCoffHeaderOffset == 0) {

-    Status = PeCoffLoaderGetImageInfo (TmpContext);

-    if (RETURN_ERROR (Status)) {

-      DEBUG ((DEBUG_ERROR,

-              "%a: PeCoffLoaderGetImageInfo () failed (Status = %r)\n",

-              __FUNCTION__, Status));

-      return Status;

-    }

-  }

-

-  if (TmpContext->IsTeImage &&

-      TmpContext->ImageAddress == ImageContext->ImageAddress) {

-    DEBUG ((DEBUG_INFO, "%a: ignoring XIP TE image at 0x%lx\n", __FUNCTION__,

-            ImageContext->ImageAddress));

-    return RETURN_UNSUPPORTED;

+  Status = PeCoffLoaderGetImageInfo (ImageContext);

+  if (RETURN_ERROR (Status)) {

+    DEBUG ((DEBUG_ERROR,

+            "%a: PeCoffLoaderGetImageInfo () failed (Status == %r)\n",

+            __FUNCTION__, Status));

+    return Status;

   }

 

-  if (TmpContext->SectionAlignment < EFI_PAGE_SIZE) {

+  if (ImageContext->SectionAlignment < EFI_PAGE_SIZE) {

     //

     // The sections need to be at least 4 KB aligned, since that is the

     // granularity at which we can tighten permissions.

     //

-    if (!TmpContext->IsTeImage) {

+    if (!ImageContext->IsTeImage) {

       DEBUG ((DEBUG_WARN,

               "%a: non-TE Image at 0x%lx has SectionAlignment < 4 KB (%lu)\n",

-              __FUNCTION__, ImageContext->ImageAddress, TmpContext->SectionAlignment));

+              __FUNCTION__, ImageContext->ImageAddress, ImageContext->SectionAlignment));

+      return RETURN_UNSUPPORTED;

     }

-    return RETURN_UNSUPPORTED;

+    ImageContext->SectionAlignment = EFI_PAGE_SIZE;

   }

 

   //

@@ -217,9 +204,9 @@ GetPeCoffSectionInformation (
   Hdr.Union = &HdrData;

   Size = sizeof (EFI_IMAGE_OPTIONAL_HEADER_UNION);

   ReadSize = Size;

-  Status = TmpContext->ImageRead (

-                         TmpContext->Handle,

-                         TmpContext->PeCoffHeaderOffset,

+  Status = ImageContext->ImageRead (

+                         ImageContext->Handle,

+                         ImageContext->PeCoffHeaderOffset,

                          &Size,

                          Hdr.Pe32

                          );

@@ -231,23 +218,28 @@ GetPeCoffSectionInformation (
     return Status;

   }

 

-  ASSERT (Hdr.Pe32->Signature == EFI_IMAGE_NT_SIGNATURE);

-

-  *SectionHeaderOffset = TmpContext->PeCoffHeaderOffset + sizeof (UINT32) +

-                        sizeof (EFI_IMAGE_FILE_HEADER);

-  *NumberOfSections    = Hdr.Pe32->FileHeader.NumberOfSections;

-

-  switch (Hdr.Pe32->OptionalHeader.Magic) {

-  case EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC:

-    *SectionHeaderOffset += Hdr.Pe32->FileHeader.SizeOfOptionalHeader;

-    break;

-  case EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC:

-    *SectionHeaderOffset += Hdr.Pe32Plus->FileHeader.SizeOfOptionalHeader;

-    break;

-  default:

-    ASSERT (FALSE);

+  if (!ImageContext->IsTeImage) {

+    ASSERT (Hdr.Pe32->Signature == EFI_IMAGE_NT_SIGNATURE);

+

+    *SectionHeaderOffset = ImageContext->PeCoffHeaderOffset + sizeof (UINT32) +

+                          sizeof (EFI_IMAGE_FILE_HEADER);

+    *NumberOfSections    = Hdr.Pe32->FileHeader.NumberOfSections;

+

+    switch (Hdr.Pe32->OptionalHeader.Magic) {

+    case EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC:

+      *SectionHeaderOffset += Hdr.Pe32->FileHeader.SizeOfOptionalHeader;

+      break;

+    case EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC:

+      *SectionHeaderOffset += Hdr.Pe32Plus->FileHeader.SizeOfOptionalHeader;

+      break;

+    default:

+      ASSERT (FALSE);

+    }

+  } else {

+    *SectionHeaderOffset = (UINTN)(sizeof (EFI_TE_IMAGE_HEADER));

+    *NumberOfSections = Hdr.Te->NumberOfSections;

+    ImageContext->ImageAddress -= (UINT32)Hdr.Te->StrippedSize - sizeof (EFI_TE_IMAGE_HEADER);

   }

-

   return RETURN_SUCCESS;

 }

 

@@ -261,7 +253,6 @@ GetStandaloneMmCorePeCoffSections (
   )

 {

   EFI_STATUS                   Status;

-  PE_COFF_LOADER_IMAGE_CONTEXT TmpContext;

 

   // Initialize the Image Context

   ZeroMem (ImageContext, sizeof (PE_COFF_LOADER_IMAGE_CONTEXT));

@@ -270,15 +261,9 @@ GetStandaloneMmCorePeCoffSections (
 

   DEBUG ((DEBUG_INFO, "Found Standalone MM PE data - 0x%x\n", TeData));

 

-  Status = PeCoffLoaderGetImageInfo (ImageContext);

-  if (EFI_ERROR (Status)) {

-    DEBUG ((DEBUG_ERROR, "Unable to locate Standalone MM Core PE-COFF Image information - 0x%x\n", Status));

-    return Status;

-  }

-

-  Status = GetPeCoffSectionInformation (ImageContext, &TmpContext, SectionHeaderOffset, NumberOfSections);

+  Status = GetPeCoffSectionInformation (ImageContext, SectionHeaderOffset, NumberOfSections);

   if (EFI_ERROR (Status)) {

-    DEBUG ((DEBUG_ERROR, "Unable to locate Standalone MM Core PE-COFF Section information - 0x%x\n", Status));

+    DEBUG ((DEBUG_ERROR, "Unable to locate Standalone MM Core PE-COFF Section information - %r\n", Status));

     return Status;

   }