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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-01-20 14:01:31 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-01-20 14:01:31 -0300
commitb4b7ff4b08e691656c9d77c758fc355833128ac0 (patch)
tree82fcb00e6b918026dc9f2d1f05ed8eee83874cc0 /net/ipv4/tcp_ipv4.c
parent35acfa0fc609f2a2cd95cef4a6a9c3a5c38f1778 (diff)
Linux-libre 4.4-gnupck-4.4-gnu
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
-rw-r--r--net/ipv4/tcp_ipv4.c224
1 files changed, 93 insertions, 131 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 5f46f5bcc..e34e2f473 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -340,7 +340,6 @@ void tcp_req_err(struct sock *sk, u32 seq)
if (seq != tcp_rsk(req)->snt_isn) {
NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
- reqsk_put(req);
} else {
/*
* Still in SYN_RECV, just remove it silently.
@@ -348,9 +347,10 @@ void tcp_req_err(struct sock *sk, u32 seq)
* created socket, and POSIX does not want network
* errors returned from accept().
*/
- NET_INC_STATS_BH(net, LINUX_MIB_LISTENDROPS);
inet_csk_reqsk_queue_drop(req->rsk_listener, req);
+ NET_INC_STATS_BH(net, LINUX_MIB_LISTENDROPS);
}
+ reqsk_put(req);
}
EXPORT_SYMBOL(tcp_req_err);
@@ -592,7 +592,7 @@ EXPORT_SYMBOL(tcp_v4_send_check);
* Exception: precedence violation. We do not implement it in any case.
*/
-static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb)
+static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb)
{
const struct tcphdr *th = tcp_hdr(skb);
struct {
@@ -811,7 +811,7 @@ static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb)
inet_twsk_put(tw);
}
-static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
+static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
struct request_sock *req)
{
/* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV
@@ -819,7 +819,7 @@ static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
*/
tcp_v4_send_ack(skb, (sk->sk_state == TCP_LISTEN) ?
tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt,
- tcp_rsk(req)->rcv_nxt, req->rcv_wnd,
+ tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd,
tcp_time_stamp,
req->ts_recent,
0,
@@ -834,11 +834,11 @@ static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
* This still operates on a request_sock only, not on a big
* socket.
*/
-static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
+static int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst,
struct flowi *fl,
struct request_sock *req,
- u16 queue_mapping,
- struct tcp_fastopen_cookie *foc)
+ struct tcp_fastopen_cookie *foc,
+ bool attach_req)
{
const struct inet_request_sock *ireq = inet_rsk(req);
struct flowi4 fl4;
@@ -849,12 +849,11 @@ static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL)
return -1;
- skb = tcp_make_synack(sk, dst, req, foc);
+ skb = tcp_make_synack(sk, dst, req, foc, attach_req);
if (skb) {
__tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr);
- skb_set_queue_mapping(skb, queue_mapping);
err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr,
ireq->ir_rmt_addr,
ireq->opt);
@@ -881,7 +880,7 @@ static void tcp_v4_reqsk_destructor(struct request_sock *req)
*/
/* Find the Key structure for an address. */
-struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk,
+struct tcp_md5sig_key *tcp_md5_do_lookup(const struct sock *sk,
const union tcp_md5_addr *addr,
int family)
{
@@ -893,7 +892,7 @@ struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk,
/* caller either holds rcu_read_lock() or socket lock */
md5sig = rcu_dereference_check(tp->md5sig_info,
sock_owned_by_user(sk) ||
- lockdep_is_held(&sk->sk_lock.slock));
+ lockdep_is_held((spinlock_t *)&sk->sk_lock.slock));
if (!md5sig)
return NULL;
#if IS_ENABLED(CONFIG_IPV6)
@@ -910,7 +909,7 @@ struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk,
}
EXPORT_SYMBOL(tcp_md5_do_lookup);
-struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk,
+struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk,
const struct sock *addr_sk)
{
const union tcp_md5_addr *addr;
@@ -1129,10 +1128,13 @@ clear_hash_noput:
}
EXPORT_SYMBOL(tcp_v4_md5_hash_skb);
+#endif
+
/* Called with rcu_read_lock() */
-static bool tcp_v4_inbound_md5_hash(struct sock *sk,
+static bool tcp_v4_inbound_md5_hash(const struct sock *sk,
const struct sk_buff *skb)
{
+#ifdef CONFIG_TCP_MD5SIG
/*
* This gets called for each TCP segment that arrives
* so we want to be efficient.
@@ -1182,10 +1184,12 @@ static bool tcp_v4_inbound_md5_hash(struct sock *sk,
return true;
}
return false;
-}
#endif
+ return false;
+}
-static void tcp_v4_init_req(struct request_sock *req, struct sock *sk_listener,
+static void tcp_v4_init_req(struct request_sock *req,
+ const struct sock *sk_listener,
struct sk_buff *skb)
{
struct inet_request_sock *ireq = inet_rsk(req);
@@ -1196,7 +1200,8 @@ static void tcp_v4_init_req(struct request_sock *req, struct sock *sk_listener,
ireq->opt = tcp_v4_save_options(skb);
}
-static struct dst_entry *tcp_v4_route_req(struct sock *sk, struct flowi *fl,
+static struct dst_entry *tcp_v4_route_req(const struct sock *sk,
+ struct flowi *fl,
const struct request_sock *req,
bool *strict)
{
@@ -1235,7 +1240,6 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = {
.route_req = tcp_v4_route_req,
.init_seq = tcp_v4_init_sequence,
.send_synack = tcp_v4_send_synack,
- .queue_hash_add = inet_csk_reqsk_queue_hash_add,
};
int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
@@ -1258,9 +1262,11 @@ EXPORT_SYMBOL(tcp_v4_conn_request);
* The three way handshake has completed - we got a valid synack -
* now create the new socket.
*/
-struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
+struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb,
struct request_sock *req,
- struct dst_entry *dst)
+ struct dst_entry *dst,
+ struct request_sock *req_unhash,
+ bool *own_req)
{
struct inet_request_sock *ireq;
struct inet_sock *newinet;
@@ -1294,7 +1300,6 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
newinet->mc_ttl = ip_hdr(skb)->ttl;
newinet->rcv_tos = ip_hdr(skb)->tos;
inet_csk(newsk)->icsk_ext_hdr_len = 0;
- sk_set_txhash(newsk);
if (inet_opt)
inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen;
newinet->inet_id = newtp->write_seq ^ jiffies;
@@ -1337,7 +1342,9 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
if (__inet_inherit_port(sk, newsk) < 0)
goto put_and_exit;
- __inet_hash_nolisten(newsk, NULL);
+ *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash));
+ if (*own_req)
+ tcp_move_syn(newtp, req);
return newsk;
@@ -1355,34 +1362,11 @@ put_and_exit:
}
EXPORT_SYMBOL(tcp_v4_syn_recv_sock);
-static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb)
+static struct sock *tcp_v4_cookie_check(struct sock *sk, struct sk_buff *skb)
{
+#ifdef CONFIG_SYN_COOKIES
const struct tcphdr *th = tcp_hdr(skb);
- const struct iphdr *iph = ip_hdr(skb);
- struct request_sock *req;
- struct sock *nsk;
-
- req = inet_csk_search_req(sk, th->source, iph->saddr, iph->daddr);
- if (req) {
- nsk = tcp_check_req(sk, skb, req, false);
- if (!nsk || nsk == sk)
- reqsk_put(req);
- return nsk;
- }
-
- nsk = inet_lookup_established(sock_net(sk), &tcp_hashinfo, iph->saddr,
- th->source, iph->daddr, th->dest, inet_iif(skb));
-
- if (nsk) {
- if (nsk->sk_state != TCP_TIME_WAIT) {
- bh_lock_sock(nsk);
- return nsk;
- }
- inet_twsk_put(inet_twsk(nsk));
- return NULL;
- }
-#ifdef CONFIG_SYN_COOKIES
if (!th->syn)
sk = cookie_v4_check(sk, skb);
#endif
@@ -1390,7 +1374,7 @@ static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb)
}
/* The socket must have it's spinlock held when we get
- * here.
+ * here, unless it is a TCP_LISTEN socket.
*
* We have a potential double-lock case here, so even when
* doing backlog processing we use the BH locking scheme.
@@ -1432,13 +1416,13 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
#endif
if (sk->sk_state == TCP_LISTEN) {
- struct sock *nsk = tcp_v4_hnd_req(sk, skb);
+ struct sock *nsk = tcp_v4_cookie_check(sk, skb);
+
if (!nsk)
goto discard;
-
if (nsk != sk) {
sock_rps_save_rxhash(nsk, skb);
- sk_mark_napi_id(sk, skb);
+ sk_mark_napi_id(nsk, skb);
if (tcp_child_process(sk, nsk, skb)) {
rsk = nsk;
goto reset;
@@ -1448,7 +1432,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
} else
sock_rps_save_rxhash(sk, skb);
- if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len)) {
+ if (tcp_rcv_state_process(sk, skb)) {
rsk = sk;
goto reset;
}
@@ -1536,7 +1520,7 @@ bool tcp_prequeue(struct sock *sk, struct sk_buff *skb)
if (likely(sk->sk_rx_dst))
skb_dst_drop(skb);
else
- skb_dst_force(skb);
+ skb_dst_force_safe(skb);
__skb_queue_tail(&tp->ucopy.prequeue, skb);
tp->ucopy.memory += skb->truesize;
@@ -1618,6 +1602,7 @@ int tcp_v4_rcv(struct sk_buff *skb)
TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph);
TCP_SKB_CB(skb)->sacked = 0;
+lookup:
sk = __inet_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest);
if (!sk)
goto no_tcp_socket;
@@ -1626,6 +1611,33 @@ process:
if (sk->sk_state == TCP_TIME_WAIT)
goto do_time_wait;
+ if (sk->sk_state == TCP_NEW_SYN_RECV) {
+ struct request_sock *req = inet_reqsk(sk);
+ struct sock *nsk = NULL;
+
+ sk = req->rsk_listener;
+ if (tcp_v4_inbound_md5_hash(sk, skb))
+ goto discard_and_relse;
+ if (likely(sk->sk_state == TCP_LISTEN)) {
+ nsk = tcp_check_req(sk, skb, req, false);
+ } else {
+ inet_csk_reqsk_queue_drop_and_put(sk, req);
+ goto lookup;
+ }
+ if (!nsk) {
+ reqsk_put(req);
+ goto discard_it;
+ }
+ if (nsk == sk) {
+ sock_hold(sk);
+ reqsk_put(req);
+ } else if (tcp_child_process(sk, nsk, skb)) {
+ tcp_v4_send_reset(nsk, skb);
+ goto discard_it;
+ } else {
+ return 0;
+ }
+ }
if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) {
NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
goto discard_and_relse;
@@ -1634,25 +1646,23 @@ process:
if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
goto discard_and_relse;
-#ifdef CONFIG_TCP_MD5SIG
- /*
- * We really want to reject the packet as early as possible
- * if:
- * o We're expecting an MD5'd packet and this is no MD5 tcp option
- * o There is an MD5 option and we're not expecting one
- */
if (tcp_v4_inbound_md5_hash(sk, skb))
goto discard_and_relse;
-#endif
nf_reset(skb);
if (sk_filter(sk, skb))
goto discard_and_relse;
- sk_incoming_cpu_update(sk);
skb->dev = NULL;
+ if (sk->sk_state == TCP_LISTEN) {
+ ret = tcp_v4_do_rcv(sk, skb);
+ goto put_and_return;
+ }
+
+ sk_incoming_cpu_update(sk);
+
bh_lock_sock_nested(sk);
tcp_sk(sk)->segs_in += max_t(u16, 1, skb_shinfo(skb)->gso_segs);
ret = 0;
@@ -1667,6 +1677,7 @@ process:
}
bh_unlock_sock(sk);
+put_and_return:
sock_put(sk);
return ret;
@@ -1737,8 +1748,7 @@ void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
- if (dst) {
- dst_hold(dst);
+ if (dst && dst_hold_safe(dst)) {
sk->sk_rx_dst = dst;
inet_sk(sk)->rx_dst_ifindex = skb->skb_iif;
}
@@ -1861,35 +1871,7 @@ static void *listening_get_next(struct seq_file *seq, void *cur)
++st->num;
++st->offset;
- if (st->state == TCP_SEQ_STATE_OPENREQ) {
- struct request_sock *req = cur;
-
- icsk = inet_csk(st->syn_wait_sk);
- req = req->dl_next;
- while (1) {
- while (req) {
- if (req->rsk_ops->family == st->family) {
- cur = req;
- goto out;
- }
- req = req->dl_next;
- }
- if (++st->sbucket >= icsk->icsk_accept_queue.listen_opt->nr_table_entries)
- break;
-get_req:
- req = icsk->icsk_accept_queue.listen_opt->syn_table[st->sbucket];
- }
- sk = sk_nulls_next(st->syn_wait_sk);
- st->state = TCP_SEQ_STATE_LISTENING;
- spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
- } else {
- icsk = inet_csk(sk);
- spin_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
- if (reqsk_queue_len(&icsk->icsk_accept_queue))
- goto start_req;
- spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
- sk = sk_nulls_next(sk);
- }
+ sk = sk_nulls_next(sk);
get_sk:
sk_nulls_for_each_from(sk, node) {
if (!net_eq(sock_net(sk), net))
@@ -1899,16 +1881,6 @@ get_sk:
goto out;
}
icsk = inet_csk(sk);
- spin_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
- if (reqsk_queue_len(&icsk->icsk_accept_queue)) {
-start_req:
- st->uid = sock_i_uid(sk);
- st->syn_wait_sk = sk;
- st->state = TCP_SEQ_STATE_OPENREQ;
- st->sbucket = 0;
- goto get_req;
- }
- spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
}
spin_unlock_bh(&ilb->lock);
st->offset = 0;
@@ -2040,7 +2012,6 @@ static void *tcp_seek_last_pos(struct seq_file *seq)
void *rc = NULL;
switch (st->state) {
- case TCP_SEQ_STATE_OPENREQ:
case TCP_SEQ_STATE_LISTENING:
if (st->bucket >= INET_LHTABLE_SIZE)
break;
@@ -2099,7 +2070,6 @@ static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
}
switch (st->state) {
- case TCP_SEQ_STATE_OPENREQ:
case TCP_SEQ_STATE_LISTENING:
rc = listening_get_next(seq, v);
if (!rc) {
@@ -2124,11 +2094,6 @@ static void tcp_seq_stop(struct seq_file *seq, void *v)
struct tcp_iter_state *st = seq->private;
switch (st->state) {
- case TCP_SEQ_STATE_OPENREQ:
- if (v) {
- struct inet_connection_sock *icsk = inet_csk(st->syn_wait_sk);
- spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
- }
case TCP_SEQ_STATE_LISTENING:
if (v != SEQ_START_TOKEN)
spin_unlock_bh(&tcp_hashinfo.listening_hash[st->bucket].lock);
@@ -2182,7 +2147,7 @@ void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo)
EXPORT_SYMBOL(tcp_proc_unregister);
static void get_openreq4(const struct request_sock *req,
- struct seq_file *f, int i, kuid_t uid)
+ struct seq_file *f, int i)
{
const struct inet_request_sock *ireq = inet_rsk(req);
long delta = req->rsk_timer.expires - jiffies;
@@ -2199,7 +2164,8 @@ static void get_openreq4(const struct request_sock *req,
1, /* timers active (only the expire timer) */
jiffies_delta_to_clock_t(delta),
req->num_timeout,
- from_kuid_munged(seq_user_ns(f), uid),
+ from_kuid_munged(seq_user_ns(f),
+ sock_i_uid(req->rsk_listener)),
0, /* non standard timer */
0, /* open_requests have no inode */
0,
@@ -2213,12 +2179,13 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i)
const struct tcp_sock *tp = tcp_sk(sk);
const struct inet_connection_sock *icsk = inet_csk(sk);
const struct inet_sock *inet = inet_sk(sk);
- struct fastopen_queue *fastopenq = icsk->icsk_accept_queue.fastopenq;
+ const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq;
__be32 dest = inet->inet_daddr;
__be32 src = inet->inet_rcv_saddr;
__u16 destp = ntohs(inet->inet_dport);
__u16 srcp = ntohs(inet->inet_sport);
int rx_queue;
+ int state;
if (icsk->icsk_pending == ICSK_TIME_RETRANS ||
icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS ||
@@ -2236,17 +2203,18 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i)
timer_expires = jiffies;
}
- if (sk->sk_state == TCP_LISTEN)
+ state = sk_state_load(sk);
+ if (state == TCP_LISTEN)
rx_queue = sk->sk_ack_backlog;
else
- /*
- * because we dont lock socket, we might find a transient negative value
+ /* Because we don't lock the socket,
+ * we might find a transient negative value.
*/
rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0);
seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX "
"%08X %5u %8d %lu %d %pK %lu %lu %u %u %d",
- i, src, srcp, dest, destp, sk->sk_state,
+ i, src, srcp, dest, destp, state,
tp->write_seq - tp->snd_una,
rx_queue,
timer_active,
@@ -2260,8 +2228,8 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i)
jiffies_to_clock_t(icsk->icsk_ack.ato),
(icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong,
tp->snd_cwnd,
- sk->sk_state == TCP_LISTEN ?
- (fastopenq ? fastopenq->max_qlen : 0) :
+ state == TCP_LISTEN ?
+ fastopenq->max_qlen :
(tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh));
}
@@ -2300,18 +2268,12 @@ static int tcp4_seq_show(struct seq_file *seq, void *v)
}
st = seq->private;
- switch (st->state) {
- case TCP_SEQ_STATE_LISTENING:
- case TCP_SEQ_STATE_ESTABLISHED:
- if (sk->sk_state == TCP_TIME_WAIT)
- get_timewait4_sock(v, seq, st->num);
- else
- get_tcp4_sock(v, seq, st->num);
- break;
- case TCP_SEQ_STATE_OPENREQ:
- get_openreq4(v, seq, st->num, st->uid);
- break;
- }
+ if (sk->sk_state == TCP_TIME_WAIT)
+ get_timewait4_sock(v, seq, st->num);
+ else if (sk->sk_state == TCP_NEW_SYN_RECV)
+ get_openreq4(v, seq, st->num);
+ else
+ get_tcp4_sock(v, seq, st->num);
out:
seq_pad(seq, '\n');
return 0;