ima: Fail rule parsing when the KEY_CHECK hook is combined with an invalid cond

The KEY_CHECK function only supports the uid, pcr, and keyrings
conditionals. Make this clear at policy load so that IMA policy authors
don't assume that other conditionals are supported.

Fixes: 5808611cccb2 ("IMA: Add KEY_CHECK func to measure keys")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 1c64bd6..81da020 100644 (file)
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -1023,6 +1023,13 @@ static bool ima_validate_rule(struct ima_rule_entry *entry)
                if (entry->action & ~(MEASURE | DONT_MEASURE))
                        return false;
 
+               if (entry->flags & ~(IMA_FUNC | IMA_UID | IMA_PCR |
+                                    IMA_KEYRINGS))
+                       return false;
+
+               if (ima_rule_contains_lsm_cond(entry))
+                       return false;
+
                break;
        default:
                return false;