ima: don't measure/appraise files on efivarfs

Update the builtin IMA policies specified on the boot command line
(eg. ima_policy="tcb|appraise_tcb") to permit accessing efivar files.
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

security/integrity/ima/ima_policy.c

@@ -107,7 +107,8 @@ static struct ima_rule_entry dont_measure_rules[] __ro_after_init = {
 	 .flags = IMA_FSMAGIC},
 	{.action = DONT_MEASURE, .fsmagic = CGROUP2_SUPER_MAGIC,
 	 .flags = IMA_FSMAGIC},
-	{.action = DONT_MEASURE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC}
+	{.action = DONT_MEASURE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_MEASURE, .fsmagic = EFIVARFS_MAGIC, .flags = IMA_FSMAGIC}
 };
 
 static struct ima_rule_entry original_measurement_rules[] __ro_after_init = {
@@ -150,6 +151,7 @@ static struct ima_rule_entry default_appraise_rules[] __ro_after_init = {
 	{.action = DONT_APPRAISE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC},
 	{.action = DONT_APPRAISE, .fsmagic = SMACK_MAGIC, .flags = IMA_FSMAGIC},
 	{.action = DONT_APPRAISE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_APPRAISE, .fsmagic = EFIVARFS_MAGIC, .flags = IMA_FSMAGIC},
 	{.action = DONT_APPRAISE, .fsmagic = CGROUP_SUPER_MAGIC, .flags = IMA_FSMAGIC},
 	{.action = DONT_APPRAISE, .fsmagic = CGROUP2_SUPER_MAGIC, .flags = IMA_FSMAGIC},
 #ifdef CONFIG_IMA_WRITE_POLICY