[PATCH] KEYS: trusted: Avoid calling null function trusted_key_exit

[Dave Kleikamp <dave.kleikamp@oracle.com>]

If one loads and unloads the trusted module, trusted_key_exit can be
NULL. Call it through static_call_cond() to avoid a kernel trap.

Fixes: 5d0682be3189 ("KEYS: trusted: Add generic trusted keys framework")

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Sumit Garg <sumit.garg@linaro.org>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-integrity@vger.kernel.org
Cc: keyrings@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: stable@vger.kernel.org
---
 security/keys/trusted-keys/trusted_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted-keys/trusted_core.c
index d5c891d8d353..8c14e04e2112 100644
--- a/security/keys/trusted-keys/trusted_core.c
+++ b/security/keys/trusted-keys/trusted_core.c
@@ -351,7 +351,7 @@ static int __init init_trusted(void)
 
 static void __exit cleanup_trusted(void)
 {
-	static_call(trusted_key_exit)();
+	static_call_cond(trusted_key_exit)();
 }
 
 late_initcall(init_trusted);
-- 
2.35.0