diff options
| author | Eric Dumazet | 2023-03-15 20:57:45 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman | 2023-10-10 22:00:34 +0200 |
| commit | c1432ece79e682cea66112dfb010e2a1ca3be9d5 (patch) | |
| tree | 443861f9db3b73e4fe523aa8f248c247c132bc3b /net/mptcp | |
| parent | 09b6fdf7a12e535dc39207b45b42b9bc9b578c75 (diff) | |
mptcp: annotate lockless accesses to sk->sk_err
[ Upstream commit 9ae8e5ad99b8ebcd3d3dd46075f3825e6f08f063 ]
mptcp_poll() reads sk->sk_err without socket lock held/owned.
Add READ_ONCE() and WRITE_ONCE() to avoid load/store tearing.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: d5fbeff1ab81 ("mptcp: move __mptcp_error_report in protocol.c")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/mptcp')
| -rw-r--r-- | net/mptcp/pm_netlink.c | 2 | ||||
| -rw-r--r-- | net/mptcp/protocol.c | 8 | ||||
| -rw-r--r-- | net/mptcp/subflow.c | 4 |
3 files changed, 7 insertions, 7 deletions
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 9127a7fd5269..5d845fcf3d09 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -2047,7 +2047,7 @@ static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) return -EMSGSIZE; - sk_err = ssk->sk_err; + sk_err = READ_ONCE(ssk->sk_err); if (sk_err && sk->sk_state == TCP_ESTABLISHED && nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) return -EMSGSIZE; diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 60e65f6325c3..84f107854eac 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2517,15 +2517,15 @@ static void mptcp_check_fastclose(struct mptcp_sock *msk) /* Mirror the tcp_reset() error propagation */ switch (sk->sk_state) { case TCP_SYN_SENT: - sk->sk_err = ECONNREFUSED; + WRITE_ONCE(sk->sk_err, ECONNREFUSED); break; case TCP_CLOSE_WAIT: - sk->sk_err = EPIPE; + WRITE_ONCE(sk->sk_err, EPIPE); break; case TCP_CLOSE: return; default: - sk->sk_err = ECONNRESET; + WRITE_ONCE(sk->sk_err, ECONNRESET); } inet_sk_state_store(sk, TCP_CLOSE); @@ -3893,7 +3893,7 @@ static __poll_t mptcp_poll(struct file *file, struct socket *sock, /* This barrier is coupled with smp_wmb() in __mptcp_error_report() */ smp_rmb(); - if (sk->sk_err) + if (READ_ONCE(sk->sk_err)) mask |= EPOLLERR; return mask; diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 168dced2434b..032661c8273f 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -1248,7 +1248,7 @@ fallback: subflow->reset_reason = MPTCP_RST_EMPTCP; reset: - ssk->sk_err = EBADMSG; + WRITE_ONCE(ssk->sk_err, EBADMSG); tcp_set_state(ssk, TCP_CLOSE); while ((skb = skb_peek(&ssk->sk_receive_queue))) sk_eat_skb(ssk, skb); @@ -1332,7 +1332,7 @@ void __mptcp_error_report(struct sock *sk) ssk_state = inet_sk_state_load(ssk); if (ssk_state == TCP_CLOSE && !sock_flag(sk, SOCK_DEAD)) inet_sk_state_store(sk, ssk_state); - sk->sk_err = -err; + WRITE_ONCE(sk->sk_err, -err); /* This barrier is coupled with smp_rmb() in mptcp_poll() */ smp_wmb(); |