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| author | Eric Dumazet <edumazet@google.com> | 2024-05-28 12:52:50 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-08-03 08:49:04 +0200 |
| commit | 11ba88ab2b78d0de7257ef97eae2fc6a72f8e307 (patch) | |
| tree | e7877b5898e957196b493ce77961cc9e3e2ea608 | |
| parent | a4391e546bcaebc5f9baf0570fe886f2ca5a379c (diff) | |
| download | linux-11ba88ab2b78d0de7257ef97eae2fc6a72f8e307.tar.gz linux-11ba88ab2b78d0de7257ef97eae2fc6a72f8e307.tar.bz2 linux-11ba88ab2b78d0de7257ef97eae2fc6a72f8e307.zip | |
tcp: add tcp_done_with_error() helper
[ Upstream commit 5e514f1cba090e1c8fff03e92a175eccfe46305f ]
tcp_reset() ends with a sequence that is carefuly ordered.
We need to fix [e]poll bugs in the following patches,
it makes sense to use a common helper.
Suggested-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20240528125253.1966136-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 853c3bd7b791 ("tcp: fix race in tcp_write_err()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | include/net/tcp.h | 1 | ||||
| -rw-r--r-- | net/ipv4/tcp.c | 2 | ||||
| -rw-r--r-- | net/ipv4/tcp_input.c | 32 |
3 files changed, 23 insertions, 12 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h index 8ea1fba84eff..cc314c383c53 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -633,6 +633,7 @@ void tcp_skb_collapse_tstamp(struct sk_buff *skb, /* tcp_input.c */ void tcp_rearm_rto(struct sock *sk); void tcp_synack_rtt_meas(struct sock *sk, struct request_sock *req); +void tcp_done_with_error(struct sock *sk, int err); void tcp_reset(struct sock *sk, struct sk_buff *skb); void tcp_skb_mark_lost_uncond_verify(struct tcp_sock *tp, struct sk_buff *skb); void tcp_fin(struct sock *sk); diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 7e162a34baec..cb79919323a6 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -589,7 +589,7 @@ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait) */ mask |= EPOLLOUT | EPOLLWRNORM; } - /* This barrier is coupled with smp_wmb() in tcp_reset() */ + /* This barrier is coupled with smp_wmb() in tcp_done_with_error() */ smp_rmb(); if (READ_ONCE(sk->sk_err) || !skb_queue_empty_lockless(&sk->sk_error_queue)) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index d72255e5262b..b1b4f44d2137 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4356,9 +4356,26 @@ static inline bool tcp_sequence(const struct tcp_sock *tp, u32 seq, u32 end_seq) !after(seq, tp->rcv_nxt + tcp_receive_window(tp)); } + +void tcp_done_with_error(struct sock *sk, int err) +{ + /* This barrier is coupled with smp_rmb() in tcp_poll() */ + WRITE_ONCE(sk->sk_err, err); + smp_wmb(); + + tcp_write_queue_purge(sk); + tcp_done(sk); + + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); +} +EXPORT_SYMBOL(tcp_done_with_error); + /* When we get a reset we do this. */ void tcp_reset(struct sock *sk, struct sk_buff *skb) { + int err; + trace_tcp_receive_reset(sk); /* mptcp can't tell us to ignore reset pkts, @@ -4370,24 +4387,17 @@ void tcp_reset(struct sock *sk, struct sk_buff *skb) /* We want the right error as BSD sees it (and indeed as we do). */ switch (sk->sk_state) { case TCP_SYN_SENT: - WRITE_ONCE(sk->sk_err, ECONNREFUSED); + err = ECONNREFUSED; break; case TCP_CLOSE_WAIT: - WRITE_ONCE(sk->sk_err, EPIPE); + err = EPIPE; break; case TCP_CLOSE: return; default: - WRITE_ONCE(sk->sk_err, ECONNRESET); + err = ECONNRESET; } - /* This barrier is coupled with smp_rmb() in tcp_poll() */ - smp_wmb(); - - tcp_write_queue_purge(sk); - tcp_done(sk); - - if (!sock_flag(sk, SOCK_DEAD)) - sk_error_report(sk); + tcp_done_with_error(sk, err); } /* |