[PATCH] keys: ensure that ->match_free() is called in request_key_and_link()

[David Howells]

From: Eric Biggers <ebigg...@google.com>

If check_cached_key() returns a non-NULL value, we still need to call
key_type::match_free() to undo key_type::match_preparse().

Fixes: 7743c48e54ee ("keys: Cache result of request_key*() temporarily in 
task_struct")
Signed-off-by: Eric Biggers <ebigg...@google.com>
Signed-off-by: David Howells <dhowe...@redhat.com>
---

 security/keys/request_key.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/security/keys/request_key.c b/security/keys/request_key.c
index 7325f382dbf4..957b9e3e1492 100644
--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -595,7 +595,7 @@ struct key *request_key_and_link(struct key_type *type,
 
        key = check_cached_key(&ctx);
        if (key)
-               return key;
+               goto error_free;
 
        /* search all the process keyrings for a key */
        rcu_read_lock();