[PATCH 1/1] SignedCapsulePkg: Add handling of NULL returned from FMP Descriptor

[PATCH 1/1] SignedCapsulePkg: Add handling of NULL returned from FMP Descriptor

[Gaurav Jain]

Firmware management protocol that does not support GetImageInfo
return Unsupported.
hence FMP Image Information Buffer is NULL.
Freeing NULL buffer results in Exception.

Added NULL check for Image Info buffer
and skip processing FMP protocol handle,
which does not support GetImageInfo.

Signed-off-by: Gaurav Jain <gaurav.jain@nxp.com>
---
 .../Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c         | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/SignedCapsulePkg/Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c b/SignedCapsulePkg/Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c
index bdb70bdb32cc..b4438ac6f55a 100644
--- a/SignedCapsulePkg/Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c
+++ b/SignedCapsulePkg/Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c
@@ -579,7 +579,7 @@ GetFmpImageDescriptors (
                   &PackageVersionName          // PackageVersionName
                   );
   if (Status != EFI_BUFFER_TOO_SMALL) {
-    DEBUG ((DEBUG_ERROR, "SystemFirmwareUpdateDxe: Unexpected Failure.  Status = %r\n", Status));
+    DEBUG ((DEBUG_INFO, "SystemFirmwareUpdateDxe: Status = %r\n", Status));
     return NULL;
   }
 
@@ -678,6 +678,9 @@ FindMatchingFmpHandles (
                                 &DescriptorSize
                                 );
 
+    if (OriginalFmpImageInfoBuf == NULL) {
+      continue;
+    }
     //
     // Loop through the set of EFI_FIRMWARE_IMAGE_DESCRIPTORs.
     //
-- 
2.7.4

Re: [edk2-devel] [PATCH 1/1] SignedCapsulePkg: Add handling of NULL returned from FMP Descriptor

[Ard Biesheuvel]

On 5/6/20 10:54 AM, Gaurav Jain via groups.io wrote:
> Firmware management protocol that does not support GetImageInfo
> return Unsupported.

The UEFI spec does not list EFI_UNSUPPORTED as a permitted return value 
for EFI_FIRMWARE_MANAGEMENT_PROTOCOL.GetImageInfo()

What is the point of producing the protocol in this case?

> hence FMP Image Information Buffer is NULL.
> Freeing NULL buffer results in Exception.
> 
> Added NULL check for Image Info buffer
> and skip processing FMP protocol handle,
> which does not support GetImageInfo.
> 
> Signed-off-by: Gaurav Jain <gaurav.jain@nxp.com>
> ---
>   .../Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c         | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/SignedCapsulePkg/Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c b/SignedCapsulePkg/Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c
> index bdb70bdb32cc..b4438ac6f55a 100644
> --- a/SignedCapsulePkg/Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c
> +++ b/SignedCapsulePkg/Universal/SystemFirmwareUpdate/SystemFirmwareUpdateDxe.c
> @@ -579,7 +579,7 @@ GetFmpImageDescriptors (
>                     &PackageVersionName          // PackageVersionName
>                     );
>     if (Status != EFI_BUFFER_TOO_SMALL) {
> -    DEBUG ((DEBUG_ERROR, "SystemFirmwareUpdateDxe: Unexpected Failure.  Status = %r\n", Status));
> +    DEBUG ((DEBUG_INFO, "SystemFirmwareUpdateDxe: Status = %r\n", Status));
>       return NULL;
>     }
>   
> @@ -678,6 +678,9 @@ FindMatchingFmpHandles (
>                                   &DescriptorSize
>                                   );
>   
> +    if (OriginalFmpImageInfoBuf == NULL) {
> +      continue;
> +    }
>       //
>       // Loop through the set of EFI_FIRMWARE_IMAGE_DESCRIPTORs.
>       //
>