[PATCH 10/12] ima: Move validation of the keyrings conditional into ima_validate_rule()

From: Tyler Hicks
Date: Mon Jun 22 2020 - 20:34:34 EST


Use ima_validate_rule() to ensure that the combination of a hook
function and the keyrings conditional is valid and that the keyrings
conditional is not specified without an explicit KEY_CHECK func
conditional. This is a code cleanup and has no user-facing change.

Signed-off-by: Tyler Hicks <tyhicks@xxxxxxxxxxxxxxxxxxx>
---
security/integrity/ima/ima_policy.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 514baf24d6a5..ae2ec2a9cdb9 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -999,6 +999,12 @@ static bool ima_validate_rule(struct ima_rule_entry *entry)
case KEXEC_KERNEL_CHECK:
case KEXEC_INITRAMFS_CHECK:
case POLICY_CHECK:
+ if (entry->flags & ~(IMA_FUNC | IMA_MASK | IMA_FSMAGIC |
+ IMA_UID | IMA_FOWNER | IMA_FSUUID |
+ IMA_INMASK | IMA_EUID | IMA_PCR |
+ IMA_FSNAME))
+ return false;
+
break;
case KEXEC_CMDLINE:
if (entry->action & ~(MEASURE | DONT_MEASURE))
@@ -1026,7 +1032,8 @@ static bool ima_validate_rule(struct ima_rule_entry *entry)
default:
return false;
}
- }
+ } else if (entry->flags & IMA_KEYRINGS)
+ return false;

return true;
}
@@ -1208,7 +1215,6 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
keyrings_len = strlen(args[0].from) + 1;

if ((entry->keyrings) ||
- (entry->func != KEY_CHECK) ||
(keyrings_len < 2)) {
result = -EINVAL;
break;
--
2.25.1