5.4-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
[ Upstream commit 099ecf59f05b5f30f42ebac0ab8cb94f9b18c90c ]
sk->sk_max_ack_backlog can be read without any lock being held at least in TCP/DCCP cases.
We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing and/or potential KCSAN warnings.
Signed-off-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net Stable-dep-of: 4d5c70e6155d ("sctp: ensure sk_state is set to CLOSED if hashing fails in sctp_listen_start") Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/sock.h | 2 +- net/dccp/proto.c | 2 +- net/ipv4/af_inet.c | 2 +- net/ipv4/inet_connection_sock.c | 2 +- net/ipv4/tcp.c | 2 +- net/ipv4/tcp_diag.c | 2 +- net/sched/em_meta.c | 2 +- net/sctp/diag.c | 2 +- net/sctp/socket.c | 4 ++-- 9 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/include/net/sock.h b/include/net/sock.h index c0d5775bc62c0..986f9724da8d0 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -883,7 +883,7 @@ static inline void sk_acceptq_added(struct sock *sk)
static inline bool sk_acceptq_is_full(const struct sock *sk) { - return READ_ONCE(sk->sk_ack_backlog) > sk->sk_max_ack_backlog; + return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); }
/* diff --git a/net/dccp/proto.c b/net/dccp/proto.c index 491b148afa8f0..add742af1c8b9 100644 --- a/net/dccp/proto.c +++ b/net/dccp/proto.c @@ -960,7 +960,7 @@ int inet_dccp_listen(struct socket *sock, int backlog) if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN))) goto out;
- sk->sk_max_ack_backlog = backlog; + WRITE_ONCE(sk->sk_max_ack_backlog, backlog); /* Really, if the socket is already in listen state * we can only allow the backlog to be adjusted. */ diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index e0d0aae343ac8..be2b786cee2bd 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -208,7 +208,7 @@ int inet_listen(struct socket *sock, int backlog) if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN))) goto out;
- sk->sk_max_ack_backlog = backlog; + WRITE_ONCE(sk->sk_max_ack_backlog, backlog); /* Really, if the socket is already in listen state * we can only allow the backlog to be adjusted. */ diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index 091999dbef335..6766a154ff854 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -767,7 +767,7 @@ static void reqsk_timer_handler(struct timer_list *t) * ones are about to clog our table. */ qlen = reqsk_queue_len(queue); - if ((qlen << 1) > max(8U, sk_listener->sk_max_ack_backlog)) { + if ((qlen << 1) > max(8U, READ_ONCE(sk_listener->sk_max_ack_backlog))) { int young = reqsk_queue_len_young(queue) << 1;
while (thresh > 2) { diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 4800422169f95..55754bf176d99 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3281,7 +3281,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info) * tcpi_sacked -> max backlog */ info->tcpi_unacked = READ_ONCE(sk->sk_ack_backlog); - info->tcpi_sacked = sk->sk_max_ack_backlog; + info->tcpi_sacked = READ_ONCE(sk->sk_max_ack_backlog); return; }
diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c index edfbab54c46f4..0d08f9e2d8d03 100644 --- a/net/ipv4/tcp_diag.c +++ b/net/ipv4/tcp_diag.c @@ -22,7 +22,7 @@ static void tcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
if (inet_sk_state_load(sk) == TCP_LISTEN) { r->idiag_rqueue = READ_ONCE(sk->sk_ack_backlog); - r->idiag_wqueue = sk->sk_max_ack_backlog; + r->idiag_wqueue = READ_ONCE(sk->sk_max_ack_backlog); } else if (sk->sk_type == SOCK_STREAM) { const struct tcp_sock *tp = tcp_sk(sk);
diff --git a/net/sched/em_meta.c b/net/sched/em_meta.c index c4c297627feac..46254968d390f 100644 --- a/net/sched/em_meta.c +++ b/net/sched/em_meta.c @@ -532,7 +532,7 @@ META_COLLECTOR(int_sk_max_ack_bl) *err = -1; return; } - dst->value = sk->sk_max_ack_backlog; + dst->value = READ_ONCE(sk->sk_max_ack_backlog); }
META_COLLECTOR(int_sk_prio) diff --git a/net/sctp/diag.c b/net/sctp/diag.c index e0785592fdd63..2fcfb8cc8bd12 100644 --- a/net/sctp/diag.c +++ b/net/sctp/diag.c @@ -417,7 +417,7 @@ static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, r->idiag_wqueue = infox->asoc->sndbuf_used; } else { r->idiag_rqueue = READ_ONCE(sk->sk_ack_backlog); - r->idiag_wqueue = sk->sk_max_ack_backlog; + r->idiag_wqueue = READ_ONCE(sk->sk_max_ack_backlog); } if (infox->sctpinfo) sctp_get_sctp_info(sk, infox->asoc, infox->sctpinfo); diff --git a/net/sctp/socket.c b/net/sctp/socket.c index eef807edd61da..efc9981481c5f 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -8407,7 +8407,7 @@ static int sctp_listen_start(struct sock *sk, int backlog) } }
- sk->sk_max_ack_backlog = backlog; + WRITE_ONCE(sk->sk_max_ack_backlog, backlog); return sctp_hash_endpoint(ep); }
@@ -8461,7 +8461,7 @@ int sctp_inet_listen(struct socket *sock, int backlog)
/* If we are already listening, just update the backlog */ if (sctp_sstate(sk, LISTENING)) - sk->sk_max_ack_backlog = backlog; + WRITE_ONCE(sk->sk_max_ack_backlog, backlog); else { err = sctp_listen_start(sk, backlog); if (err)