[PATCH v4 02/12] integrity: Do not allow mok keyring updates following init
From: Eric Snowberg <eric.snowberg@oracle.com>
Date: 2021-08-19 00:22:47
Also in:
keyrings, linux-crypto, linux-integrity, lkml
Subsystem:
extended verification module (evm), integrity measurement architecture (ima), security subsystem, the rest · Maintainers:
Mimi Zohar, Roberto Sassu, Dmitry Kasatkin, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
The mok keyring is setup during init. No additional keys should be allowed to be added afterwards. Leave the permission as read only. Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> --- v2: Initial version v4: Unmodified from v2 --- security/integrity/digsig.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
index e07334504ef1..5cad38e6f56a 100644
--- a/security/integrity/digsig.c
+++ b/security/integrity/digsig.c@@ -140,7 +140,8 @@ int __init integrity_init_keyring(const unsigned int id) return -ENOMEM; restriction->check = restrict_link_to_ima; - perm |= KEY_USR_WRITE; + if (id != INTEGRITY_KEYRING_MOK) + perm |= KEY_USR_WRITE; out: return __integrity_init_keyring(id, perm, restriction);
--
2.18.4