[PATCH v14 12/26] ima: Only accept AUDIT rules for non-init_ima_ns namespaces for now

From: Stefan Berger
Date: Thu Sep 15 2022 - 15:33:13 EST


For non-init_ima_ns namespaces, only accept AUDIT rules for now. Reject
all rules that require support for measuring, appraisal, and hashing.

Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
Acked-by: Christian Brauner <brauner@xxxxxxxxxx>
Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>

---
v9:
- Jump to err_audit when unsupported rules are detected
---
security/integrity/ima/ima_policy.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 18fd19ecb402..e81eebc7d41e 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -1865,6 +1865,17 @@ static int ima_parse_rule(struct ima_namespace *ns,
result = -EINVAL;
break;
}
+
+ /* IMA namespace only accepts AUDIT rules */
+ if (ns != &init_ima_ns && result == 0) {
+ switch (entry->action) {
+ case MEASURE:
+ case APPRAISE:
+ case HASH:
+ result = -EINVAL;
+ goto err_audit;
+ }
+ }
}
if (!result && !ima_validate_rule(entry))
result = -EINVAL;
@@ -1886,6 +1897,7 @@ static int ima_parse_rule(struct ima_namespace *ns,
"verity rules should include d-ngv2");
}

+err_audit:
audit_log_format(ab, "res=%d", !result);
audit_log_end(ab);
return result;
--
2.36.1