On Wed, 19 Feb 2020 at 21:46, Serge E. Hallyn [off-list ref] wrote:

On Wed, Feb 19, 2020 at 06:19:07PM +0100, Ard Biesheuvel wrote:

quoted

Testing the value of the efi.get_variable function pointer is not
the right way to establish whether the platform supports EFI
variables at runtime. Instead, use the newly added granular check
that can test for the presence of each EFI runtime service
individually.

Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 security/integrity/platform_certs/load_uefi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/security/integrity/platform_certs/load_uefi.c b/security/integrity/platform_certs/load_uefi.c
index 111898aad56e..e2fe1bd3abb9 100644
--- a/security/integrity/platform_certs/load_uefi.c
+++ b/security/integrity/platform_certs/load_uefi.c

@@ -76,7 +76,7 @@ static int __init load_uefi_certs(void)
      unsigned long dbsize = 0, dbxsize = 0, moksize = 0;
      int rc = 0;

-     if (!efi.get_variable)
+     if (!efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))

Sorry, where is this defined?

Apologies, I failed to cc everyone on the whole series.

It is defined in the first patch.

https://lore.kernel.org/linux-efi/20200219171907.11894-1-ardb@kernel.org/ (local)