tcp/dccp: add inet_csk_reqsk_queue_drop_and_put() helper

edumazet · davem330 · commit f03f2e154f52 · 2015-10-16T00:52:18.000-07:00
Let's reduce the confusion about inet_csk_reqsk_queue_drop() : In many cases we also need to release reference on request socket, so add a helper to do this, reducing code size and complexity. Fixes: 4bdc3d6 ("tcp/dccp: fix behavior of stale SYN_RECV request sockets") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h
@@ -299,6 +299,7 @@ static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk)
 }
 
 void inet_csk_reqsk_queue_drop(struct sock *sk, struct request_sock *req);
+void inet_csk_reqsk_queue_drop_and_put(struct sock *sk, struct request_sock *req);
 
 void inet_csk_destroy_sock(struct sock *sk);
 void inet_csk_prepare_forced_close(struct sock *sk);
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
@@ -828,7 +828,7 @@ static int dccp_v4_rcv(struct sk_buff *skb)
 		if (likely(sk->sk_state == DCCP_LISTEN)) {
 			nsk = dccp_check_req(sk, skb, req);
 		} else {
-			inet_csk_reqsk_queue_drop(sk, req);
+			inet_csk_reqsk_queue_drop_and_put(sk, req);
 			goto lookup;
 		}
 		if (!nsk) {
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
@@ -686,7 +686,7 @@ static int dccp_v6_rcv(struct sk_buff *skb)
 		if (likely(sk->sk_state == DCCP_LISTEN)) {
 			nsk = dccp_check_req(sk, skb, req);
 		} else {
-			inet_csk_reqsk_queue_drop(sk, req);
+			inet_csk_reqsk_queue_drop_and_put(sk, req);
 			goto lookup;
 		}
 		if (!nsk) {
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
@@ -546,6 +546,13 @@ void inet_csk_reqsk_queue_drop(struct sock *sk, struct request_sock *req)
 }
 EXPORT_SYMBOL(inet_csk_reqsk_queue_drop);
 
+void inet_csk_reqsk_queue_drop_and_put(struct sock *sk, struct request_sock *req)
+{
+	inet_csk_reqsk_queue_drop(sk, req);
+	reqsk_put(req);
+}
+EXPORT_SYMBOL(inet_csk_reqsk_queue_drop_and_put);
+
 static void reqsk_timer_handler(unsigned long data)
 {
 	struct request_sock *req = (struct request_sock *)data;
@@ -608,8 +615,7 @@ static void reqsk_timer_handler(unsigned long data)
 		return;
 	}
 drop:
-	inet_csk_reqsk_queue_drop(sk_listener, req);
-	reqsk_put(req);
+	inet_csk_reqsk_queue_drop_and_put(sk_listener, req);
 }
 
 static void reqsk_queue_hash_req(struct request_sock *req,
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
@@ -1591,7 +1591,7 @@ int tcp_v4_rcv(struct sk_buff *skb)
 		if (likely(sk->sk_state == TCP_LISTEN)) {
 			nsk = tcp_check_req(sk, skb, req, false);
 		} else {
-			inet_csk_reqsk_queue_drop(sk, req);
+			inet_csk_reqsk_queue_drop_and_put(sk, req);
 			goto lookup;
 		}
 		if (!nsk) {
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
@@ -1386,7 +1386,7 @@ static int tcp_v6_rcv(struct sk_buff *skb)
 		if (likely(sk->sk_state == TCP_LISTEN)) {
 			nsk = tcp_check_req(sk, skb, req, false);
 		} else {
-			inet_csk_reqsk_queue_drop(sk, req);
+			inet_csk_reqsk_queue_drop_and_put(sk, req);
 			goto lookup;
 		}
 		if (!nsk) {

Original file line number	Diff line number	Diff line change
`@@ -299,6 +299,7 @@ static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk)`
`299`	`299`	`}`
`300`	`300`
`301`	`301`	`void inet_csk_reqsk_queue_drop(struct sock sk, struct request_sock req);`
	`302`	`+void inet_csk_reqsk_queue_drop_and_put(struct sock sk, struct request_sock req);`
`302`	`303`
`303`	`304`	`void inet_csk_destroy_sock(struct sock *sk);`
`304`	`305`	`void inet_csk_prepare_forced_close(struct sock *sk);`
Original file line number	Diff line number	Diff line change
`@@ -828,7 +828,7 @@ static int dccp_v4_rcv(struct sk_buff *skb)`
`828`	`828`	`if (likely(sk->sk_state == DCCP_LISTEN)) {`
`829`	`829`	`nsk = dccp_check_req(sk, skb, req);`
`830`	`830`	`} else {`
`831`		`- inet_csk_reqsk_queue_drop(sk, req);`
	`831`	`+ inet_csk_reqsk_queue_drop_and_put(sk, req);`
`832`	`832`	`goto lookup;`
`833`	`833`	`}`
`834`	`834`	`if (!nsk) {`
Original file line number	Diff line number	Diff line change
`@@ -686,7 +686,7 @@ static int dccp_v6_rcv(struct sk_buff *skb)`
`686`	`686`	`if (likely(sk->sk_state == DCCP_LISTEN)) {`
`687`	`687`	`nsk = dccp_check_req(sk, skb, req);`
`688`	`688`	`} else {`
`689`		`- inet_csk_reqsk_queue_drop(sk, req);`
	`689`	`+ inet_csk_reqsk_queue_drop_and_put(sk, req);`
`690`	`690`	`goto lookup;`
`691`	`691`	`}`
`692`	`692`	`if (!nsk) {`
Original file line number	Diff line number	Diff line change
`@@ -546,6 +546,13 @@ void inet_csk_reqsk_queue_drop(struct sock sk, struct request_sock req)`
`546`	`546`	`}`
`547`	`547`	`EXPORT_SYMBOL(inet_csk_reqsk_queue_drop);`
`548`	`548`
	`549`	`+void inet_csk_reqsk_queue_drop_and_put(struct sock sk, struct request_sock req)`
	`550`	`+{`
	`551`	`+ inet_csk_reqsk_queue_drop(sk, req);`
	`552`	`+ reqsk_put(req);`
	`553`	`+}`
	`554`	`+EXPORT_SYMBOL(inet_csk_reqsk_queue_drop_and_put);`
	`555`	`+`
`549`	`556`	`static void reqsk_timer_handler(unsigned long data)`
`550`	`557`	`{`
`551`	`558`	`struct request_sock req = (struct request_sock )data;`
`@@ -608,8 +615,7 @@ static void reqsk_timer_handler(unsigned long data)`
`608`	`615`	`return;`
`609`	`616`	`}`
`610`	`617`	`drop:`
`611`		`- inet_csk_reqsk_queue_drop(sk_listener, req);`
`612`		`- reqsk_put(req);`
	`618`	`+ inet_csk_reqsk_queue_drop_and_put(sk_listener, req);`
`613`	`619`	`}`
`614`	`620`
`615`	`621`	`static void reqsk_queue_hash_req(struct request_sock *req,`
Original file line number	Diff line number	Diff line change
`@@ -1591,7 +1591,7 @@ int tcp_v4_rcv(struct sk_buff *skb)`
`1591`	`1591`	`if (likely(sk->sk_state == TCP_LISTEN)) {`
`1592`	`1592`	`nsk = tcp_check_req(sk, skb, req, false);`
`1593`	`1593`	`} else {`
`1594`		`- inet_csk_reqsk_queue_drop(sk, req);`
	`1594`	`+ inet_csk_reqsk_queue_drop_and_put(sk, req);`
`1595`	`1595`	`goto lookup;`
`1596`	`1596`	`}`
`1597`	`1597`	`if (!nsk) {`
Original file line number	Diff line number	Diff line change
`@@ -1386,7 +1386,7 @@ static int tcp_v6_rcv(struct sk_buff *skb)`
`1386`	`1386`	`if (likely(sk->sk_state == TCP_LISTEN)) {`
`1387`	`1387`	`nsk = tcp_check_req(sk, skb, req, false);`
`1388`	`1388`	`} else {`
`1389`		`- inet_csk_reqsk_queue_drop(sk, req);`
	`1389`	`+ inet_csk_reqsk_queue_drop_and_put(sk, req);`
`1390`	`1390`	`goto lookup;`
`1391`	`1391`	`}`
`1392`	`1392`	`if (!nsk) {`