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path: root/net/ipv4/tcp_ipv4.c
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Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
-rw-r--r--net/ipv4/tcp_ipv4.c66
1 files changed, 52 insertions, 14 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 6d88219c5e2..0543561da99 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -328,26 +328,29 @@ static void do_pmtu_discovery(struct sock *sk, struct iphdr *iph, u32 mtu)
*
*/
-void tcp_v4_err(struct sk_buff *skb, u32 info)
+void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
{
- struct iphdr *iph = (struct iphdr *)skb->data;
- struct tcphdr *th = (struct tcphdr *)(skb->data + (iph->ihl << 2));
+ struct iphdr *iph = (struct iphdr *)icmp_skb->data;
+ struct tcphdr *th = (struct tcphdr *)(icmp_skb->data + (iph->ihl << 2));
+ struct inet_connection_sock *icsk;
struct tcp_sock *tp;
struct inet_sock *inet;
- const int type = icmp_hdr(skb)->type;
- const int code = icmp_hdr(skb)->code;
+ const int type = icmp_hdr(icmp_skb)->type;
+ const int code = icmp_hdr(icmp_skb)->code;
struct sock *sk;
+ struct sk_buff *skb;
__u32 seq;
+ __u32 remaining;
int err;
- struct net *net = dev_net(skb->dev);
+ struct net *net = dev_net(icmp_skb->dev);
- if (skb->len < (iph->ihl << 2) + 8) {
+ if (icmp_skb->len < (iph->ihl << 2) + 8) {
ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS);
return;
}
sk = inet_lookup(net, &tcp_hashinfo, iph->daddr, th->dest,
- iph->saddr, th->source, inet_iif(skb));
+ iph->saddr, th->source, inet_iif(icmp_skb));
if (!sk) {
ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS);
return;
@@ -367,6 +370,7 @@ void tcp_v4_err(struct sk_buff *skb, u32 info)
if (sk->sk_state == TCP_CLOSE)
goto out;
+ icsk = inet_csk(sk);
tp = tcp_sk(sk);
seq = ntohl(th->seq);
if (sk->sk_state != TCP_LISTEN &&
@@ -393,6 +397,39 @@ void tcp_v4_err(struct sk_buff *skb, u32 info)
}
err = icmp_err_convert[code].errno;
+ /* check if icmp_skb allows revert of backoff
+ * (see draft-zimmermann-tcp-lcd) */
+ if (code != ICMP_NET_UNREACH && code != ICMP_HOST_UNREACH)
+ break;
+ if (seq != tp->snd_una || !icsk->icsk_retransmits ||
+ !icsk->icsk_backoff)
+ break;
+
+ icsk->icsk_backoff--;
+ inet_csk(sk)->icsk_rto = __tcp_set_rto(tp) <<
+ icsk->icsk_backoff;
+ tcp_bound_rto(sk);
+
+ skb = tcp_write_queue_head(sk);
+ BUG_ON(!skb);
+
+ remaining = icsk->icsk_rto - min(icsk->icsk_rto,
+ tcp_time_stamp - TCP_SKB_CB(skb)->when);
+
+ if (remaining) {
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+ remaining, TCP_RTO_MAX);
+ } else if (sock_owned_by_user(sk)) {
+ /* RTO revert clocked out retransmission,
+ * but socket is locked. Will defer. */
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+ HZ/20, TCP_RTO_MAX);
+ } else {
+ /* RTO revert clocked out retransmission.
+ * Will retransmit now */
+ tcp_retransmit_timer(sk);
+ }
+
break;
case ICMP_TIME_EXCEEDED:
err = EHOSTUNREACH;
@@ -849,7 +886,7 @@ int tcp_v4_md5_do_add(struct sock *sk, __be32 addr,
}
sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
}
- if (tcp_alloc_md5sig_pool() == NULL) {
+ if (tcp_alloc_md5sig_pool(sk) == NULL) {
kfree(newkey);
return -ENOMEM;
}
@@ -970,8 +1007,9 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, char __user *optval,
if (!tcp_sk(sk)->md5sig_info) {
struct tcp_sock *tp = tcp_sk(sk);
- struct tcp_md5sig_info *p = kzalloc(sizeof(*p), GFP_KERNEL);
+ struct tcp_md5sig_info *p;
+ p = kzalloc(sizeof(*p), sk->sk_allocation);
if (!p)
return -EINVAL;
@@ -979,7 +1017,7 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, char __user *optval,
sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
}
- newkey = kmemdup(cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL);
+ newkey = kmemdup(cmd.tcpm_key, cmd.tcpm_keylen, sk->sk_allocation);
if (!newkey)
return -ENOMEM;
return tcp_v4_md5_do_add(sk, sin->sin_addr.s_addr,
@@ -1158,7 +1196,7 @@ struct request_sock_ops tcp_request_sock_ops __read_mostly = {
};
#ifdef CONFIG_TCP_MD5SIG
-static struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = {
+static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = {
.md5_lookup = tcp_v4_reqsk_md5_lookup,
.calc_md5_hash = tcp_v4_md5_hash_skb,
};
@@ -1717,7 +1755,7 @@ int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw)
return 0;
}
-struct inet_connection_sock_af_ops ipv4_specific = {
+const struct inet_connection_sock_af_ops ipv4_specific = {
.queue_xmit = ip_queue_xmit,
.send_check = tcp_v4_send_check,
.rebuild_header = inet_sk_rebuild_header,
@@ -1737,7 +1775,7 @@ struct inet_connection_sock_af_ops ipv4_specific = {
};
#ifdef CONFIG_TCP_MD5SIG
-static struct tcp_sock_af_ops tcp_sock_ipv4_specific = {
+static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = {
.md5_lookup = tcp_v4_md5_lookup,
.calc_md5_hash = tcp_v4_md5_hash_skb,
.md5_add = tcp_v4_md5_add_func,