RDMA/rtrs-srv: Check return values while processing info request

While processing info request, it could so happen that the srv_path goes
to CLOSING state, cause of any of the error events from RDMA. That state
change should be picked up while trying to change the state in
process_info_req, by checking the return value. In case the state change
call in process_info_req fails, we fail the processing.

We should also check the return value for rtrs_srv_path_up, since it
sends a link event to the client above, and the client can fail for any
reason.

Fixes: 9cb83748 ("RDMA/rtrs: server: main functionality")
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Link: https://lore.kernel.org/r/20231120154146.920486-4-haris.iqbal@ionos.comSigned-off-by: Leon Romanovsky <leon@kernel.org>

drivers/infiniband/ulp/rtrs/rtrs-srv.c

@@ -710,20 +710,23 @@ static void rtrs_srv_info_rsp_done(struct ib_cq *cq, struct ib_wc *wc)
 	WARN_ON(wc->opcode != IB_WC_SEND);
 }
 
-static void rtrs_srv_path_up(struct rtrs_srv_path *srv_path)
+static int rtrs_srv_path_up(struct rtrs_srv_path *srv_path)
 {
 	struct rtrs_srv_sess *srv = srv_path->srv;
 	struct rtrs_srv_ctx *ctx = srv->ctx;
-	int up;
+	int up, ret = 0;
 
 	mutex_lock(&srv->paths_ev_mutex);
 	up = ++srv->paths_up;
 	if (up == 1)
-		ctx->ops.link_ev(srv, RTRS_SRV_LINK_EV_CONNECTED, NULL);
+		ret = ctx->ops.link_ev(srv, RTRS_SRV_LINK_EV_CONNECTED, NULL);
 	mutex_unlock(&srv->paths_ev_mutex);
 
 	/* Mark session as established */
-	srv_path->established = true;
+	if (!ret)
+		srv_path->established = true;
+
+	return ret;
 }
 
 static void rtrs_srv_path_down(struct rtrs_srv_path *srv_path)
@@ -852,7 +855,12 @@ static int process_info_req(struct rtrs_srv_con *con,
 		goto iu_free;
 	kobject_get(&srv_path->kobj);
 	get_device(&srv_path->srv->dev);
-	rtrs_srv_change_state(srv_path, RTRS_SRV_CONNECTED);
+	err = rtrs_srv_change_state(srv_path, RTRS_SRV_CONNECTED);
+	if (!err) {
+		rtrs_err(s, "rtrs_srv_change_state(), err: %d\n", err);
+		goto iu_free;
+	}
+
 	rtrs_srv_start_hb(srv_path);
 
 	/*
@@ -861,7 +869,11 @@ static int process_info_req(struct rtrs_srv_con *con,
 	 * all connections are successfully established.  Thus, simply notify
 	 * listener with a proper event if we are the first path.
 	 */
-	rtrs_srv_path_up(srv_path);
+	err = rtrs_srv_path_up(srv_path);
+	if (err) {
+		rtrs_err(s, "rtrs_srv_path_up(), err: %d\n", err);
+		goto iu_free;
+	}
 
 	ib_dma_sync_single_for_device(srv_path->s.dev->ib_dev,
 				      tx_iu->dma_addr,