Re: [PATCH] MdeModulePkg/AcpiTableDxe: consider version mask when removing tables

["Zeng, Star" <star.zeng@intel.com>]

Reviewed-by: Star Zeng <star.zeng@intel.com>

-----Original Message-----
From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org] 
Sent: Monday, March 20, 2017 10:52 PM
To: edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>; Tian, Feng <feng.tian@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Subject: [PATCH] MdeModulePkg/AcpiTableDxe: consider version mask when removing tables

Invocations of EFI_ACPI_TABLE_PROTOCOL::UninstallAcpiTable() may result in a crash when the value of PcdAcpiExposedTableVersions does not include EFI_ACPI_TABLE_VERSION_1_0B.

The reason is that EFI_ACPI_TABLE_PROTOCOL::InstallAcpiTable() will only populate the Rsdt1/Rsdt3 pointers when EFI_ACPI_TABLE_VERSION_1_0B is set, whereas EFI_ACPI_TABLE_PROTOCOL::UninstallAcpiTable() will invoke PublishTables with EFI_ACPI_TABLE_VERSION_1_0B alawys set, resulting in a NULL pointer dereference of the Rsdt1/Rsdt3 pointers.

So take PcdAcpiExposedTableVersions into account for UninstallAcpiTable as well.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 MdeModulePkg/Universal/Acpi/AcpiTableDxe/AcpiTableProtocol.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/MdeModulePkg/Universal/Acpi/AcpiTableDxe/AcpiTableProtocol.c b/MdeModulePkg/Universal/Acpi/AcpiTableDxe/AcpiTableProtocol.c
index 4bb848df5203..a635e1de5a7c 100644
--- a/MdeModulePkg/Universal/Acpi/AcpiTableDxe/AcpiTableProtocol.c
+++ b/MdeModulePkg/Universal/Acpi/AcpiTableDxe/AcpiTableProtocol.c
@@ -290,24 +290,27 @@ UninstallAcpiTable (  {
   EFI_ACPI_TABLE_INSTANCE   *AcpiTableInstance;
   EFI_STATUS                Status;
+  EFI_ACPI_TABLE_VERSION    Version;
 
   //
   // Get the instance of the ACPI table protocol
   //
   AcpiTableInstance = EFI_ACPI_TABLE_INSTANCE_FROM_THIS (This);
 
+  Version = PcdGet32 (PcdAcpiExposedTableVersions);
+
   //
   // Uninstall the ACPI table
   //
   Status = RemoveTableFromList (
              AcpiTableInstance,
-             EFI_ACPI_TABLE_VERSION_1_0B | ACPI_TABLE_VERSION_GTE_2_0,
+             Version,
              TableKey
              );
   if (!EFI_ERROR (Status)) {
     Status = PublishTables (
                AcpiTableInstance,
-               EFI_ACPI_TABLE_VERSION_1_0B | ACPI_TABLE_VERSION_GTE_2_0
+               Version
                );
   }
 
--
2.7.4