net: sctp: sctp_auth_key_put: use kzfree instead of kfree

For sensitive data like keying material, it is common practice to zero
out keys before returning the memory back to the allocator. Thus, use
kzfree instead of kfree.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NVlad Yasevich <vyasevich@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/sctp/auth.c

@@ -71,7 +71,7 @@ void sctp_auth_key_put(struct sctp_auth_bytes *key)
 		return;
 
 	if (atomic_dec_and_test(&key->refcnt)) {
-		kfree(key);
+		kzfree(key);
 		SCTP_DBG_OBJCNT_DEC(keys);
 	}
 }