IMA: prevent keys on the .ima_blacklist from being removed

Set the KEY_FLAGS_KEEP on the .ima_blacklist to prevent userspace
from removing keys from the keyring.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/security/integrity/ima/ima_mok.c b/security/integrity/ima/ima_mok.c
index 18e37f57f512..8dad9a2b8e47 100644
--- a/security/integrity/ima/ima_mok.c
+++ b/security/integrity/ima/ima_mok.c
@@ -47,7 +47,9 @@ __init int ima_mok_init(void)
         if (IS_ERR(ima_mok_keyring) || IS_ERR(ima_blacklist_keyring))
                 panic("Can't allocate IMA MOK or blacklist keyrings.");
         set_bit(KEY_FLAG_TRUSTED_ONLY, &ima_mok_keyring->flags);
+
         set_bit(KEY_FLAG_TRUSTED_ONLY, &ima_blacklist_keyring->flags);
+        set_bit(KEY_FLAG_KEEP, &ima_blacklist_keyring->flags);
         return 0;
 }