From 92ad19559ea9a8ec6f158480934ae26ebfe2c14f Mon Sep 17 00:00:00 2001 From: "Lee, Chun-Yi" Date: Sat, 18 Dec 2021 10:09:05 +0800 Subject: [PATCH] integrity: Do not load MOK and MOKx when secure boot be disabled The security of Machine Owner Key (MOK) relies on secure boot. When secure boot is disabled, EFI firmware will not verify binary code. Then arbitrary efi binary code can modify MOK when rebooting. This patch prevents MOK/MOKx be loaded when secure boot be disabled. Signed-off-by: "Lee, Chun-Yi" Reviewed-by: Petr Vorel Signed-off-by: Mimi Zohar --- security/integrity/platform_certs/load_uefi.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/security/integrity/platform_certs/load_uefi.c b/security/integrity/platform_certs/load_uefi.c index f290f78c3f30..08b6d12f99b4 100644 --- a/security/integrity/platform_certs/load_uefi.c +++ b/security/integrity/platform_certs/load_uefi.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include #include "../integrity.h" @@ -176,6 +177,10 @@ static int __init load_uefi_certs(void) kfree(dbx); } + /* the MOK/MOKx can not be trusted when secure boot is disabled */ + if (!arch_ima_get_secureboot()) + return 0; + mokx = get_cert_list(L"MokListXRT", &mok_var, &mokxsize, &status); if (!mokx) { if (status == EFI_NOT_FOUND)