[PATCH v2] KEYS: trusted: Avoid calling null function trusted_key_exit

[PATCH v2] KEYS: trusted: Avoid calling null function trusted_key_exit

[Dave Kleikamp]

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
---
v2 changes:
Header cleanup - removed empty line and cc:stable
 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

Re: [PATCH v2] KEYS: trusted: Avoid calling null function trusted_key_exit

[Sumit Garg]

On Thu, 27 Jan 2022 at 02:02, Dave Kleikamp <dave.kleikamp@oracle.com> wrote:
>
> 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
> ---
> v2 changes:
> Header cleanup - removed empty line and cc:stable
>  security/keys/trusted-keys/trusted_core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>

Thanks for the fix.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>

-Sumit

> 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
>