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Diffstat (limited to 'net/ipv4/tcp.c')
-rw-r--r--net/ipv4/tcp.c63
1 files changed, 39 insertions, 24 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 68f89fe7f923..00648a478c6a 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -515,6 +515,7 @@ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
__poll_t mask;
struct sock *sk = sock->sk;
const struct tcp_sock *tp = tcp_sk(sk);
+ u8 shutdown;
int state;
sock_poll_wait(file, sock, wait);
@@ -557,9 +558,10 @@ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
* NOTE. Check for TCP_CLOSE is added. The goal is to prevent
* blocking on fresh not-connected or disconnected socket. --ANK
*/
- if (sk->sk_shutdown == SHUTDOWN_MASK || state == TCP_CLOSE)
+ shutdown = READ_ONCE(sk->sk_shutdown);
+ if (shutdown == SHUTDOWN_MASK || state == TCP_CLOSE)
mask |= EPOLLHUP;
- if (sk->sk_shutdown & RCV_SHUTDOWN)
+ if (shutdown & RCV_SHUTDOWN)
mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
/* Connected or passive Fast Open socket? */
@@ -575,8 +577,8 @@ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
if (tcp_stream_is_readable(tp, target, sk))
mask |= EPOLLIN | EPOLLRDNORM;
- if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
- if (sk_stream_is_writeable(sk)) {
+ if (!(shutdown & SEND_SHUTDOWN)) {
+ if (__sk_stream_is_writeable(sk, 1)) {
mask |= EPOLLOUT | EPOLLWRNORM;
} else { /* send SIGIO later */
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
@@ -588,7 +590,7 @@ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
* pairs with the input side.
*/
smp_mb__after_atomic();
- if (sk_stream_is_writeable(sk))
+ if (__sk_stream_is_writeable(sk, 1))
mask |= EPOLLOUT | EPOLLWRNORM;
}
} else
@@ -2338,14 +2340,13 @@ bool tcp_check_oom(struct sock *sk, int shift)
return too_many_orphans || out_of_socket_memory;
}
-void tcp_close(struct sock *sk, long timeout)
+void __tcp_close(struct sock *sk, long timeout)
{
struct sk_buff *skb;
int data_was_unread = 0;
int state;
- lock_sock(sk);
- sk->sk_shutdown = SHUTDOWN_MASK;
+ WRITE_ONCE(sk->sk_shutdown, SHUTDOWN_MASK);
if (sk->sk_state == TCP_LISTEN) {
tcp_set_state(sk, TCP_CLOSE);
@@ -2505,6 +2506,12 @@ adjudge_to_death:
out:
bh_unlock_sock(sk);
local_bh_enable();
+}
+
+void tcp_close(struct sock *sk, long timeout)
+{
+ lock_sock(sk);
+ __tcp_close(sk, timeout);
release_sock(sk);
sock_put(sk);
}
@@ -2561,6 +2568,12 @@ int tcp_disconnect(struct sock *sk, int flags)
int old_state = sk->sk_state;
u32 seq;
+ /* Deny disconnect if other threads are blocked in sk_wait_event()
+ * or inet_wait_for_connect().
+ */
+ if (sk->sk_wait_pending)
+ return -EBUSY;
+
if (old_state != TCP_CLOSE)
tcp_set_state(sk, TCP_CLOSE);
@@ -2593,7 +2606,7 @@ int tcp_disconnect(struct sock *sk, int flags)
if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
inet_reset_saddr(sk);
- sk->sk_shutdown = 0;
+ WRITE_ONCE(sk->sk_shutdown, 0);
sock_reset_flag(sk, SOCK_DONE);
tp->srtt_us = 0;
tp->rcv_rtt_last_tsecr = 0;
@@ -2987,18 +3000,18 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
case TCP_LINGER2:
if (val < 0)
- tp->linger2 = -1;
- else if (val > net->ipv4.sysctl_tcp_fin_timeout / HZ)
- tp->linger2 = 0;
+ WRITE_ONCE(tp->linger2, -1);
+ else if (val > TCP_FIN_TIMEOUT_MAX / HZ)
+ WRITE_ONCE(tp->linger2, TCP_FIN_TIMEOUT_MAX);
else
- tp->linger2 = val * HZ;
+ WRITE_ONCE(tp->linger2, val * HZ);
break;
case TCP_DEFER_ACCEPT:
/* Translate value in seconds to number of retransmits */
- icsk->icsk_accept_queue.rskq_defer_accept =
- secs_to_retrans(val, TCP_TIMEOUT_INIT / HZ,
- TCP_RTO_MAX / HZ);
+ WRITE_ONCE(icsk->icsk_accept_queue.rskq_defer_accept,
+ secs_to_retrans(val, TCP_TIMEOUT_INIT / HZ,
+ TCP_RTO_MAX / HZ));
break;
case TCP_WINDOW_CLAMP:
@@ -3086,7 +3099,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
err = tcp_repair_set_window(tp, optval, optlen);
break;
case TCP_NOTSENT_LOWAT:
- tp->notsent_lowat = val;
+ WRITE_ONCE(tp->notsent_lowat, val);
sk->sk_write_space(sk);
break;
case TCP_INQ:
@@ -3363,7 +3376,8 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
switch (optname) {
case TCP_MAXSEG:
val = tp->mss_cache;
- if (!val && ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)))
+ if (tp->rx_opt.user_mss &&
+ ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)))
val = tp->rx_opt.user_mss;
if (tp->repair)
val = tp->rx_opt.mss_clamp;
@@ -3387,13 +3401,14 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
val = icsk->icsk_syn_retries ? : net->ipv4.sysctl_tcp_syn_retries;
break;
case TCP_LINGER2:
- val = tp->linger2;
+ val = READ_ONCE(tp->linger2);
if (val >= 0)
val = (val ? : READ_ONCE(net->ipv4.sysctl_tcp_fin_timeout)) / HZ;
break;
case TCP_DEFER_ACCEPT:
- val = retrans_to_secs(icsk->icsk_accept_queue.rskq_defer_accept,
- TCP_TIMEOUT_INIT / HZ, TCP_RTO_MAX / HZ);
+ val = READ_ONCE(icsk->icsk_accept_queue.rskq_defer_accept);
+ val = retrans_to_secs(val, TCP_TIMEOUT_INIT / HZ,
+ TCP_RTO_MAX / HZ);
break;
case TCP_WINDOW_CLAMP:
val = tp->window_clamp;
@@ -3539,7 +3554,7 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
break;
case TCP_FASTOPEN:
- val = icsk->icsk_accept_queue.fastopenq.max_qlen;
+ val = READ_ONCE(icsk->icsk_accept_queue.fastopenq.max_qlen);
break;
case TCP_FASTOPEN_CONNECT:
@@ -3554,7 +3569,7 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
val = tcp_time_stamp_raw() + tp->tsoffset;
break;
case TCP_NOTSENT_LOWAT:
- val = tp->notsent_lowat;
+ val = READ_ONCE(tp->notsent_lowat);
break;
case TCP_INQ:
val = tp->recvmsg_inq;
@@ -3802,7 +3817,7 @@ void tcp_done(struct sock *sk)
if (req)
reqsk_fastopen_remove(sk, req, false);
- sk->sk_shutdown = SHUTDOWN_MASK;
+ WRITE_ONCE(sk->sk_shutdown, SHUTDOWN_MASK);
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_state_change(sk);
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-01 20:58:00 +0000