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-rw-r--r--include/linux/tcp.h7
-rw-r--r--include/net/request_sock.h4
-rw-r--r--include/net/tcp.h1
-rw-r--r--net/ipv4/inet_connection_sock.c11
-rw-r--r--net/ipv4/tcp.c18
-rw-r--r--net/ipv4/tcp_input.c45
-rw-r--r--net/ipv4/tcp_ipv4.c8
-rw-r--r--net/ipv4/tcp_minisocks.c32
-rw-r--r--net/ipv4/tcp_timer.c5
9 files changed, 33 insertions, 98 deletions
diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 18e62e3d406f..b31b6b74aa28 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -239,11 +239,6 @@ static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req)
return (struct tcp_request_sock *)req;
}
-struct tcp_deferred_accept_info {
- struct sock *listen_sk;
- struct request_sock *request;
-};
-
struct tcp_sock {
/* inet_connection_sock has to be the first member of tcp_sock */
struct inet_connection_sock inet_conn;
@@ -379,8 +374,6 @@ struct tcp_sock {
unsigned int keepalive_intvl; /* time interval between keep alive probes */
int linger2;
- struct tcp_deferred_accept_info defer_tcp_accept;
-
unsigned long last_synq_overflow;
u32 tso_deferred;
diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index b220b5f624de..0c96e7bed5db 100644
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -115,8 +115,8 @@ struct request_sock_queue {
struct request_sock *rskq_accept_head;
struct request_sock *rskq_accept_tail;
rwlock_t syn_wait_lock;
- u16 rskq_defer_accept;
- /* 2 bytes hole, try to pack */
+ u8 rskq_defer_accept;
+ /* 3 bytes hole, try to pack */
struct listen_sock *listen_opt;
};
diff --git a/include/net/tcp.h b/include/net/tcp.h
index d448310c82c1..cf54034019d9 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -139,7 +139,6 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo);
#define MAX_TCP_KEEPINTVL 32767
#define MAX_TCP_KEEPCNT 127
#define MAX_TCP_SYNCNT 127
-#define MAX_TCP_ACCEPT_DEFERRED 65535
#define TCP_SYNQ_INTERVAL (HZ/5) /* Period of SYNACK timer */
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 828ea211ff21..045e799d3e1d 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -419,7 +419,8 @@ void inet_csk_reqsk_queue_prune(struct sock *parent,
struct inet_connection_sock *icsk = inet_csk(parent);
struct request_sock_queue *queue = &icsk->icsk_accept_queue;
struct listen_sock *lopt = queue->listen_opt;
- int thresh = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
+ int max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
+ int thresh = max_retries;
unsigned long now = jiffies;
struct request_sock **reqp, *req;
int i, budget;
@@ -455,6 +456,9 @@ void inet_csk_reqsk_queue_prune(struct sock *parent,
}
}
+ if (queue->rskq_defer_accept)
+ max_retries = queue->rskq_defer_accept;
+
budget = 2 * (lopt->nr_table_entries / (timeout / interval));
i = lopt->clock_hand;
@@ -462,8 +466,9 @@ void inet_csk_reqsk_queue_prune(struct sock *parent,
reqp=&lopt->syn_table[i];
while ((req = *reqp) != NULL) {
if (time_after_eq(now, req->expires)) {
- if (req->retrans < thresh &&
- !req->rsk_ops->rtx_syn_ack(parent, req)) {
+ if ((req->retrans < (inet_rsk(req)->acked ? max_retries : thresh)) &&
+ (inet_rsk(req)->acked ||
+ !req->rsk_ops->rtx_syn_ack(parent, req))) {
unsigned long timeo;
if (req->retrans++ == 0)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index ab66683b8043..fc54a48fde1e 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2112,12 +2112,15 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
break;
case TCP_DEFER_ACCEPT:
- if (val < 0) {
- err = -EINVAL;
- } else {
- if (val > MAX_TCP_ACCEPT_DEFERRED)
- val = MAX_TCP_ACCEPT_DEFERRED;
- icsk->icsk_accept_queue.rskq_defer_accept = val;
+ icsk->icsk_accept_queue.rskq_defer_accept = 0;
+ if (val > 0) {
+ /* Translate value in seconds to number of
+ * retransmits */
+ while (icsk->icsk_accept_queue.rskq_defer_accept < 32 &&
+ val > ((TCP_TIMEOUT_INIT / HZ) <<
+ icsk->icsk_accept_queue.rskq_defer_accept))
+ icsk->icsk_accept_queue.rskq_defer_accept++;
+ icsk->icsk_accept_queue.rskq_defer_accept++;
}
break;
@@ -2299,7 +2302,8 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
val = (val ? : sysctl_tcp_fin_timeout) / HZ;
break;
case TCP_DEFER_ACCEPT:
- val = icsk->icsk_accept_queue.rskq_defer_accept;
+ val = !icsk->icsk_accept_queue.rskq_defer_accept ? 0 :
+ ((TCP_TIMEOUT_INIT / HZ) << (icsk->icsk_accept_queue.rskq_defer_accept - 1));
break;
case TCP_WINDOW_CLAMP:
val = tp->window_clamp;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index eba873e9b560..cad73b7dfef0 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4541,49 +4541,6 @@ static void tcp_urg(struct sock *sk, struct sk_buff *skb, struct tcphdr *th)
}
}
-static int tcp_defer_accept_check(struct sock *sk)
-{
- struct tcp_sock *tp = tcp_sk(sk);
-
- if (tp->defer_tcp_accept.request) {
- int queued_data = tp->rcv_nxt - tp->copied_seq;
- int hasfin = !skb_queue_empty(&sk->sk_receive_queue) ?
- tcp_hdr((struct sk_buff *)
- sk->sk_receive_queue.prev)->fin : 0;
-
- if (queued_data && hasfin)
- queued_data--;
-
- if (queued_data &&
- tp->defer_tcp_accept.listen_sk->sk_state == TCP_LISTEN) {
- if (sock_flag(sk, SOCK_KEEPOPEN)) {
- inet_csk_reset_keepalive_timer(sk,
- keepalive_time_when(tp));
- } else {
- inet_csk_delete_keepalive_timer(sk);
- }
-
- inet_csk_reqsk_queue_add(
- tp->defer_tcp_accept.listen_sk,
- tp->defer_tcp_accept.request,
- sk);
-
- tp->defer_tcp_accept.listen_sk->sk_data_ready(
- tp->defer_tcp_accept.listen_sk, 0);
-
- sock_put(tp->defer_tcp_accept.listen_sk);
- sock_put(sk);
- tp->defer_tcp_accept.listen_sk = NULL;
- tp->defer_tcp_accept.request = NULL;
- } else if (hasfin ||
- tp->defer_tcp_accept.listen_sk->sk_state != TCP_LISTEN) {
- tcp_reset(sk);
- return -1;
- }
- }
- return 0;
-}
-
static int tcp_copy_to_iovec(struct sock *sk, struct sk_buff *skb, int hlen)
{
struct tcp_sock *tp = tcp_sk(sk);
@@ -4944,8 +4901,6 @@ step5:
tcp_data_snd_check(sk);
tcp_ack_snd_check(sk);
-
- tcp_defer_accept_check(sk);
return 0;
csum_error:
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 4f8485c67d1a..97a230026e13 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1918,14 +1918,6 @@ int tcp_v4_destroy_sock(struct sock *sk)
sk->sk_sndmsg_page = NULL;
}
- if (tp->defer_tcp_accept.request) {
- reqsk_free(tp->defer_tcp_accept.request);
- sock_put(tp->defer_tcp_accept.listen_sk);
- sock_put(sk);
- tp->defer_tcp_accept.listen_sk = NULL;
- tp->defer_tcp_accept.request = NULL;
- }
-
atomic_dec(&tcp_sockets_allocated);
return 0;
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 019c8c16e5cc..8245247a6ceb 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -571,8 +571,10 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb,
does sequence test, SYN is truncated, and thus we consider
it a bare ACK.
- Both ends (listening sockets) accept the new incoming
- connection and try to talk to each other. 8-)
+ If icsk->icsk_accept_queue.rskq_defer_accept, we silently drop this
+ bare ACK. Otherwise, we create an established connection. Both
+ ends (listening sockets) accept the new incoming connection and try
+ to talk to each other. 8-)
Note: This case is both harmless, and rare. Possibility is about the
same as us discovering intelligent life on another plant tomorrow.
@@ -640,6 +642,13 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb,
if (!(flg & TCP_FLAG_ACK))
return NULL;
+ /* If TCP_DEFER_ACCEPT is set, drop bare ACK. */
+ if (inet_csk(sk)->icsk_accept_queue.rskq_defer_accept &&
+ TCP_SKB_CB(skb)->end_seq == tcp_rsk(req)->rcv_isn + 1) {
+ inet_rsk(req)->acked = 1;
+ return NULL;
+ }
+
/* OK, ACK is valid, create big socket and
* feed this segment to it. It will repeat all
* the tests. THIS SEGMENT MUST MOVE SOCKET TO
@@ -678,24 +687,7 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb,
inet_csk_reqsk_queue_unlink(sk, req, prev);
inet_csk_reqsk_queue_removed(sk, req);
- if (inet_csk(sk)->icsk_accept_queue.rskq_defer_accept &&
- TCP_SKB_CB(skb)->end_seq == tcp_rsk(req)->rcv_isn + 1) {
-
- /* the accept queue handling is done is est recv slow
- * path so lets make sure to start there
- */
- tcp_sk(child)->pred_flags = 0;
- sock_hold(sk);
- sock_hold(child);
- tcp_sk(child)->defer_tcp_accept.listen_sk = sk;
- tcp_sk(child)->defer_tcp_accept.request = req;
-
- inet_csk_reset_keepalive_timer(child,
- inet_csk(sk)->icsk_accept_queue.rskq_defer_accept * HZ);
- } else {
- inet_csk_reqsk_queue_add(sk, req, child);
- }
-
+ inet_csk_reqsk_queue_add(sk, req, child);
return child;
listen_overflow:
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 4de68cf5f2aa..63ed9d6830e7 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -489,11 +489,6 @@ static void tcp_keepalive_timer (unsigned long data)
goto death;
}
- if (tp->defer_tcp_accept.request && sk->sk_state == TCP_ESTABLISHED) {
- tcp_send_active_reset(sk, GFP_ATOMIC);
- goto death;
- }
-
if (!sock_flag(sk, SOCK_KEEPOPEN) || sk->sk_state == TCP_CLOSE)
goto out;