diff --git a/fs/ksmbd/auth.c b/fs/ksmbd/auth.c
index 6e61b5bc7d86ed..cead696b656a8c 100644
--- a/fs/ksmbd/auth.c
+++ b/fs/ksmbd/auth.c
@@ -727,8 +727,9 @@ static int generate_key(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 		goto smb3signkey_ret;
 	}
 
-	if (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
-	    conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
+	if (key_size == SMB3_ENC_DEC_KEY_SIZE &&
+	    (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
+	     conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
 		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L256, 4);
 	else
 		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L128, 4);