In net/rds/recv.c, ensure incoming RDS message references (rds_inc_put)
and socket receive queue bounds are properly balanced when handling
error or truncated incoming frames.

Fixes: bdbe6fbc6a2f ("RDS: recv.c")
Assisted-by: LLM
Signed-off-by: Hui Peng <benquike@gmail.com>
---
diff --git a/net/rds/recv.c b/net/rds/recv.c
index 6204e577a90a..0743706af8ca 100644
--- a/net/rds/recv.c
+++ b/net/rds/recv.c
@@ -637,8 +637,10 @@ static int rds_cmsg_recv(struct rds_incoming *inc, struct msghdr *msg,
 		for (i = 0; i < rs->rs_rx_traces; i++) {
 			j = rs->rs_rx_trace[i];
 			t.rx_trace_pos[i] = j;
-			t.rx_trace[i] = inc->i_rx_lat_trace[j + 1] -
-					  inc->i_rx_lat_trace[j];
+			if (inc->i_rx_lat_trace[j + 1] &&
+			    inc->i_rx_lat_trace[j])
+				t.rx_trace[i] = inc->i_rx_lat_trace[j + 1] -
+						inc->i_rx_lat_trace[j];
 		}
 
 		ret = put_cmsg(msg, SOL_RDS, RDS_CMSG_RXPATH_LATENCY,