Improve detection of EFI program validity

EfiLib/BdsConnect.c

@@ -247,7 +247,7 @@ BdsLibConnectAllDriversToAllControllers (
  VOID
  )
 {
- EFI_STATUS Status;
+ EFI_STATUS Status = EFI_UNSUPPORTED;
 
  do {
  //
@@ -262,7 +262,8 @@ BdsLibConnectAllDriversToAllControllers (
  // If anything is Dispatched Status == EFI_SUCCESS and we will try
  // the connect again.
  //
- Status = gDS->Dispatch ();
+ if (gDS)
+ Status = gDS->Dispatch ();
 
  } while (!EFI_ERROR (Status));
 

EfiLib/BdsTianoCore.c

@@ -107,7 +107,11 @@ BdsLibConnectDevicePath (
  // Status == EFI_SUCCESS means a driver was dispatched
  // Status == EFI_NOT_FOUND means no new drivers were dispatched
  //
- Status = gDS->Dispatch ();
+ if (gDS) {
+ Status = gDS->Dispatch ();
+ } else {
+ Status = EFI_NOT_FOUND;
+ }
  }
 #endif
 

NEWS.txt

@@ -8,6 +8,9 @@
 
 - Fixed a memory leak in JPEG handling code.
 
+- Fixed a bug that could cause some EFI programs (notably Pete Batard's
+ drivers on ARM64 systems) to be incorrectly marked as invalid.
+
 0.14.0 (3/4/2023):
 ------------------
 

include/version.h

@@ -13,6 +13,6 @@
 #ifndef __VERSION_H
 #define __VERSION_H
 
-#define REFIND_VERSION L"0.14.0.5"
+#define REFIND_VERSION L"0.14.0.6"
 
 #endif

refind/launch_efi.c

@@ -86,6 +86,11 @@
 
 #define FAT_ARCH 0x0ef1fab9 /* ID for Apple "fat" binary */
 
+// Amount of a file to read to search for the EFI identifying signatures....
+// I've seen signatures as far in as 3680 (0xE60), so read a bit more than
+// that....
+#define EFI_HEADER_SIZE 3800
+
 static VOID WarnSecureBootError(CHAR16 *Name, BOOLEAN Verbose) {
  if (Name == NULL)
  Name = L"the loader";
@@ -120,10 +125,16 @@ UINTN IsValidLoader(EFI_FILE_PROTOCOL *RootDir, CHAR16 *FileName) {
  BOOLEAN IsValid = TRUE;
  EFI_STATUS Status;
  EFI_FILE_HANDLE FileHandle;
- CHAR8 Header[512];
+ CHAR8 *Header;
  CHAR16 *TypeDesc = L"a valid";
- UINTN Size = sizeof(Header);
+ UINTN LoadedSize = EFI_HEADER_SIZE;
+ UINTN SignaturePos;
 
+ Header = AllocatePool(EFI_HEADER_SIZE);
+ if (!Header) {
+ LOG(1, LOG_LINE_NORMAL, L"Unable to allocate memory in IsValidLoader()!");
+ return LOADER_TYPE_INVALID;
+ }
  if ((RootDir == NULL) || (FileName == NULL)) {
  // Assume valid here, because Macs produce NULL RootDir (& maybe FileName)
  // when launching from a Firewire drive. This should be handled better, but
@@ -135,18 +146,28 @@ UINTN IsValidLoader(EFI_FILE_PROTOCOL *RootDir, CHAR16 *FileName) {
  if (EFI_ERROR(Status))
  return LOADER_TYPE_INVALID;
 
- Status = refit_call3_wrapper(FileHandle->Read, FileHandle, &Size, Header);
+ Status = refit_call3_wrapper(FileHandle->Read, FileHandle, &LoadedSize, Header);
  refit_call1_wrapper(FileHandle->Close, FileHandle);
 
- IsValid = !EFI_ERROR(Status) &&
- Size == sizeof(Header) &&
+ if (EFI_ERROR(Status)) {
+ MyFreePool(Header);
+ LOG(1, LOG_LINE_NORMAL, L"Error reading %s to determine if it's a valid loader!", FileName);
+ return LOADER_TYPE_INVALID;
+ }
+ SignaturePos = *(UINT32 *)&Header[0x3c];
+ LOG(4, LOG_LINE_NORMAL, L"In IsValidLoader(), LoadedSize is %lu, SignaturePos is %lu", LoadedSize, SignaturePos);
+ // Search for the normal signatures for an EFI binary....
+ IsValid = (LoadedSize == EFI_HEADER_SIZE) &&
  ((Header[0] == 'M' && Header[1] == 'Z' &&
- (Size = *(UINT32 *)&Header[0x3c]) < 0x180 &&
- Header[Size] == 'P' && Header[Size+1] == 'E' &&
- Header[Size+2] == 0 && Header[Size+3] == 0 &&
- *(UINT16 *)&Header[Size+4] == EFI_STUB_ARCH) ||
+ (SignaturePos < (EFI_HEADER_SIZE - 8)) &&
+ Header[SignaturePos] == 'P' && Header[SignaturePos+1] == 'E' &&
+ Header[SignaturePos+2] == 0 && Header[SignaturePos+3] == 0 &&
+ *(UINT16 *)&Header[SignaturePos+4] == EFI_STUB_ARCH) ||
  (*(UINT32 *)&Header == FAT_ARCH));
  if (!IsValid) {
+ // Search for indications that this is a gzipped file. Note, however,
+ // that we don't dig deeper into gzipped files, so some invalid
+ // gzipped files could be called valid.
  if ((Header[0] == (CHAR8) 0x1F && Header[1] == (CHAR8) 0x8B) && GlobalConfig.GzippedLoaders) {
  LoaderType = LOADER_TYPE_GZIP;
  TypeDesc = L"a gzipped";
@@ -156,6 +177,7 @@ UINTN IsValidLoader(EFI_FILE_PROTOCOL *RootDir, CHAR16 *FileName) {
  }
  }
  LOG(1, LOG_LINE_NORMAL, L"'%s' is %s loader file", FileName, TypeDesc);
+ MyFreePool(Header);
 #endif
  return LoaderType;
 } // UINTN IsValidLoader()

refind/main.c

@@ -249,12 +249,19 @@ VOID RescanAll(BOOLEAN DisplayMessage, BOOLEAN Reconnect) {
 
 // Minimal initialization function
 static VOID InitializeLib(IN EFI_HANDLE ImageHandle, IN EFI_SYSTEM_TABLE *SystemTable) {
+ EFI_STATUS Status;
+
  gST = SystemTable;
  // gImageHandle = ImageHandle;
  gBS = SystemTable->BootServices;
  // gRS = SystemTable->RuntimeServices;
  gRT = SystemTable->RuntimeServices; // Some BDS functions need gRT to be set
- EfiGetSystemConfigurationTable (&gEfiDxeServicesTableGuid, (VOID **) &gDS);
+ Status = EfiGetSystemConfigurationTable (&gEfiDxeServicesTableGuid, (VOID **) &gDS);
+ if (EFI_ERROR(Status)) {
+ LOG(1, LOG_LINE_NORMAL, L"WARNING: EfiGetSystemConfigurationTable() returned error status %lu!", Status);
+ LOG(1, LOG_LINE_NORMAL, L"Some functionality will be impaired!");
+ gDS = 0;
+ }
 }
 
 #endif