RDS: fix rds_sock reference bug while doing bind

One need to take rds socket reference while using it and release it
once done with it. rds_add_bind() code path does not do that so
lets fix it.
Signed-off-by: NSantosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>

net/rds/bind.c

@@ -61,8 +61,10 @@ static struct rds_sock *rds_bind_lookup(__be32 addr, __be16 port,
 		cmp = ((u64)be32_to_cpu(rs->rs_bound_addr) << 32) |
 		      be16_to_cpu(rs->rs_bound_port);
 
-		if (cmp == needle)
+		if (cmp == needle) {
+			rds_sock_addref(rs);
 			return rs;
+		}
 	}
 
 	if (insert) {
@@ -94,10 +96,10 @@ struct rds_sock *rds_find_bound(__be32 addr, __be16 port)
 	rs = rds_bind_lookup(addr, port, NULL);
 	read_unlock_irqrestore(&rds_bind_lock, flags);
 
-	if (rs && !sock_flag(rds_rs_to_sk(rs), SOCK_DEAD))
-		rds_sock_addref(rs);
-	else
+	if (rs && sock_flag(rds_rs_to_sk(rs), SOCK_DEAD)) {
+		rds_sock_put(rs);
 		rs = NULL;
+	}
 
 	rdsdebug("returning rs %p for %pI4:%u\n", rs, &addr,
 		ntohs(port));
@@ -123,14 +125,18 @@ static int rds_add_bound(struct rds_sock *rs, __be32 addr, __be16 *port)
 	write_lock_irqsave(&rds_bind_lock, flags);
 
 	do {
+		struct rds_sock *rrs;
 		if (rover == 0)
 			rover++;
-		if (!rds_bind_lookup(addr, cpu_to_be16(rover), rs)) {
+		rrs = rds_bind_lookup(addr, cpu_to_be16(rover), rs);
+		if (!rrs) {
 			*port = rs->rs_bound_port;
 			ret = 0;
 			rdsdebug("rs %p binding to %pI4:%d\n",
 			  rs, &addr, (int)ntohs(*port));
 			break;
+		} else {
+			rds_sock_put(rrs);
 		}
 	} while (rover++ != last);