diff options
| author | Eric Dumazet <edumazet@google.com> | 2021-07-02 13:09:03 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-28 11:13:45 +0200 |
| commit | d694db2f90ffc44b8fb9f9ae2d38edaa4aa4f444 (patch) | |
| tree | 0b0a3bbc3db8f5a284650924f43821e07ce58bdf | |
| parent | e0355a0ad31a1d677b2a4514206de4902bd550e8 (diff) | |
tcp: annotate data races around tp->mtu_info
commit 561022acb1ce62e50f7a8258687a21b84282a4cb upstream.
While tp->mtu_info is read while socket is owned, the write
sides happen from err handlers (tcp_v[46]_mtu_reduced)
which only own the socket spinlock.
Fixes: 563d34d05786 ("tcp: dont drop MTU reduction indications")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 4 | ||||
| -rw-r--r-- | net/ipv6/tcp_ipv6.c | 4 |
2 files changed, 4 insertions, 4 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index ac6135555e24a..71236aa7388d7 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -348,7 +348,7 @@ void tcp_v4_mtu_reduced(struct sock *sk) if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) return; - mtu = tcp_sk(sk)->mtu_info; + mtu = READ_ONCE(tcp_sk(sk)->mtu_info); dst = inet_csk_update_pmtu(sk, mtu); if (!dst) return; @@ -516,7 +516,7 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) if (sk->sk_state == TCP_LISTEN) goto out; - tp->mtu_info = info; + WRITE_ONCE(tp->mtu_info, info); if (!sock_owned_by_user(sk)) { tcp_v4_mtu_reduced(sk); } else { diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 2e7a28f327a86..5121012cc7413 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -340,7 +340,7 @@ static void tcp_v6_mtu_reduced(struct sock *sk) if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) return; - dst = inet6_csk_update_pmtu(sk, tcp_sk(sk)->mtu_info); + dst = inet6_csk_update_pmtu(sk, READ_ONCE(tcp_sk(sk)->mtu_info)); if (!dst) return; @@ -429,7 +429,7 @@ static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, if (!ip6_sk_accept_pmtu(sk)) goto out; - tp->mtu_info = ntohl(info); + WRITE_ONCE(tp->mtu_info, ntohl(info)); if (!sock_owned_by_user(sk)) tcp_v6_mtu_reduced(sk); else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, |