tyler.durden
/
audk
mirror of https://github.com/acidanthera/audk.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

OvmfPkg/QemuKernelLoaderFsDxe: call VerifyBlob after fetch from fw_cfg 

In QemuKernelLoaderFsDxeEntrypoint we use FetchBlob to read the content
of the kernel/initrd/cmdline from the QEMU fw_cfg interface.  Insert a
call to VerifyBlob after fetching to allow BlobVerifierLib
implementations to add a verification step for these blobs.

This will allow confidential computing OVMF builds to add verification
mechanisms for these blobs that originate from an untrusted source
(QEMU).

The null implementation of BlobVerifierLib does nothing in VerifyBlob,
and therefore no functional change is expected.

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ashish Kalra <ashish.kalra@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3457
Co-developed-by: James Bottomley <jejb@linux.ibm.com>
Signed-off-by: James Bottomley <jejb@linux.ibm.com>
Signed-off-by: Dov Murik <dovmurik@linux.ibm.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
This commit is contained in:
Dov Murik 2021-07-01 12:20:40 +00:00 committed by mergify[bot]
parent 6bf5580a3d
commit d10ad8444f
1 changed files with 9 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
OvmfPkg/QemuKernelLoaderFsDxe/QemuKernelLoaderFsDxe.c
View File

@ -17,6 +17,7 @@
#include <Guid/QemuKernelLoaderFsMedia.h>
#include <Library/BaseLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/BlobVerifierLib.h>
#include <Library/DebugLib.h>
#include <Library/DevicePathLib.h>
#include <Library/MemoryAllocationLib.h>
@ -1039,6 +1040,14 @@ QemuKernelLoaderFsDxeEntrypoint (
if (EFI_ERROR (Status)) {
goto FreeBlobs;
}
Status = VerifyBlob (
CurrentBlob->Name,
CurrentBlob->Data,
CurrentBlob->Size
);
if (EFI_ERROR (Status)) {
goto FreeBlobs;
}
mTotalBlobBytes += CurrentBlob->Size;
}
KernelBlob = &mKernelBlob[KernelBlobTypeKernel];