[PATCH 5.8 244/464] ima: Fail rule parsing when the KEY_CHECK hook is combined with an invalid cond

[Greg Kroah-Hartman]

From: Tyler Hicks <tyhicks@xxxxxxxxxxxxxxxxxxx>

[ Upstream commit eb624fe214a2e156ddafd9868377cf91499f789d ]

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@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 security/integrity/ima/ima_policy.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index a77e0b34e72f7..3e3e568c81309 100644
--- 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;
-- 
2.25.1