From 42426e6eae764da650b963ad1cd957fee7df351a Mon Sep 17 00:00:00 2001 From: Andrew Boie Date: Tue, 12 Nov 2013 10:24:01 -0500 Subject: [PATCH] fix verify_mok() () Fix the return value semantics. If the MokList doesn't exist, we are OK. If the MokList was compromised but we were able to erase it, that is OK too. Only if the list can't be nuked do we return an error. () Fix use of potentially uninitialized attribute variable () Actually use the return value when called from verify_buffer. Change-Id: If16df21d79c52a1726928df96d133390cde4cb7e Signed-off-by: Andrew Boie --- shim.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/shim.c b/shim.c index 23dd0ee..dcb36d0 100644 --- a/shim.c +++ b/shim.c @@ -670,13 +670,12 @@ static EFI_STATUS verify_mok (void) { status = get_variable_attr(L"MokList", &MokListData, &MokListDataSize, shim_lock_guid, &attributes); - if (attributes & EFI_VARIABLE_RUNTIME_ACCESS) { + if (!EFI_ERROR(status) && attributes & EFI_VARIABLE_RUNTIME_ACCESS) { Print(L"MokList is compromised!\nErase all keys in MokList!\n"); if (LibDeleteVariable(L"MokList", &shim_lock_guid) != EFI_SUCCESS) { Print(L"Failed to erase MokList\n"); + return EFI_ACCESS_DENIED; } - status = EFI_ACCESS_DENIED; - return status; } if (MokListData) @@ -722,7 +721,9 @@ static EFI_STATUS verify_buffer (char *data, int datasize, /* * Check that the MOK database hasn't been modified */ - verify_mok(); + status = verify_mok(); + if (status != EFI_SUCCESS) + return status; /* * Ensure that the binary isn't blacklisted