SecurityPkg: Fix assert when setting key from eMMC/SD/USB

When secure boot is enabled, if one loads keys from a FAT formatted
eMMC/SD/USB when trying to provision PK/KEK/DB keys via the menu,
an assert in StrLen() occurs.
This is because the filename starts on odd address, which is not a uint16
aligned boundary: https://bugzilla.tianocore.org/show_bug.cgi?id=1003

There are further known issues with the OpenFileByDevicePath() function;
those are tracked by
<https://bugzilla.tianocore.org/show_bug.cgi?id=1008>.

Cc: Chao Zhang <chao.b.zhang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Roman Bacik <roman.bacik@broadcom.com>
Reviewed-by: "Yao, Jiewen" <jiewen.yao@intel.com>
[lersek@redhat.com: whitespace fixes]
[lersek@redhat.com: reference TianoCore BZ#1008]
Reviewed-by: Laszlo Ersek <lersek@redhat.com>

1 files changed, 11 insertions, 2 deletions

diff --git a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c
index 1b6f888042..2a26c20f39 100644
--- a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c
+++ b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigFileExplorer.c
@@ -123,6 +123,8 @@ OpenFileByDevicePath(
   EFI_FILE_PROTOCOL               *Handle1;

   EFI_FILE_PROTOCOL               *Handle2;

   EFI_HANDLE                      DeviceHandle;

+  CHAR16                          *PathName;

+  UINTN                           PathLength;

 

   if ((FilePath == NULL || FileHandle == NULL)) {

     return EFI_INVALID_PARAMETER;

@@ -173,6 +175,11 @@ OpenFileByDevicePath(
     //

     Handle2  = Handle1;

     Handle1 = NULL;

+    PathLength = DevicePathNodeLength (*FilePath) - sizeof (EFI_DEVICE_PATH_PROTOCOL);

+    PathName = AllocateCopyPool (PathLength, ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName);

+    if (PathName == NULL) {

+      return EFI_OUT_OF_RESOURCES;

+    }

 

     //

     // Try to test opening an existing file

@@ -180,7 +187,7 @@ OpenFileByDevicePath(
     Status = Handle2->Open (

                           Handle2,

                           &Handle1,

-                          ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName,

+                          PathName,

                           OpenMode &~EFI_FILE_MODE_CREATE,

                           0

                          );

@@ -192,7 +199,7 @@ OpenFileByDevicePath(
       Status = Handle2->Open (

                             Handle2,

                             &Handle1,

-                            ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName,

+                            PathName,

                             OpenMode,

                             Attributes

                            );

@@ -202,6 +209,8 @@ OpenFileByDevicePath(
     //

     Handle2->Close (Handle2);

 

+    FreePool (PathName);

+

     if (EFI_ERROR(Status)) {

       return (Status);

     }