inet: drop prev pointer handling in request sock

When request sock are put in ehash table, the whole notion
of having a previous request to update dl_next is pointless.

Also, following patch will get rid of big purge timer,
so we want to delete a request sock without holding listener lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 9 deletions

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index ddd0b1f25b96..19c3770f1e97 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -458,12 +458,12 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
         }
 
         switch (sk->sk_state) {
-                struct request_sock *req, **prev;
+                struct request_sock *req;
         case TCP_LISTEN:
                 if (sock_owned_by_user(sk))
                         goto out;
 
-                req = inet_csk_search_req(sk, &prev, th->dest,
+                req = inet_csk_search_req(sk, th->dest,
                                           iph->daddr, iph->saddr);
                 if (!req)
                         goto out;
@@ -484,7 +484,7 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
                  * created socket, and POSIX does not want network
                  * errors returned from accept().
                  */
-                inet_csk_reqsk_queue_drop(sk, req, prev);
+                inet_csk_reqsk_queue_drop(sk, req);
                 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
                 goto out;
 
@@ -1392,15 +1392,14 @@ EXPORT_SYMBOL(tcp_v4_syn_recv_sock);
 
 static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb)
 {
-        struct tcphdr *th = tcp_hdr(skb);
+        const struct tcphdr *th = tcp_hdr(skb);
         const struct iphdr *iph = ip_hdr(skb);
+        struct request_sock *req;
         struct sock *nsk;
-        struct request_sock **prev;
-        /* Find possible connection requests. */
-        struct request_sock *req = inet_csk_search_req(sk, &prev, th->source,
-                                                       iph->saddr, iph->daddr);
+
+        req = inet_csk_search_req(sk, th->source, iph->saddr, iph->daddr);
         if (req)
-                return tcp_check_req(sk, skb, req, prev, false);
+                return tcp_check_req(sk, skb, req, false);
 
         nsk = inet_lookup_established(sock_net(sk), &tcp_hashinfo, iph->saddr,
                         th->source, iph->daddr, th->dest, inet_iif(skb));