[RFC 09/20] ima: Only accept AUDIT rules for IMA non-init_ima_ns namespaces for now

[Stefan Berger]

Only accept AUDIT rules for non-init_ima_ns namespaces rejecting all rules
that require support for measuring, appraisal, and hashing.

Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
---
 security/integrity/ima/ima_policy.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 96e7d63167e8..02e96da2faff 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -1785,6 +1785,16 @@ static int ima_parse_rule(struct ima_namespace *ns,
 			result = -EINVAL;
 			break;
 		}
+
+		/* IMA namespace only accepts AUDIT rules */
+		if (ns != &init_ima_ns) {
+			switch (entry->action) {
+			case MEASURE:
+			case APPRAISE:
+			case HASH:
+				result = -EINVAL;
+			}
+		}
 	}
 	if (!result && !ima_validate_rule(entry))
 		result = -EINVAL;
-- 
2.31.1