diff options
| author | Eric Dumazet <edumazet@google.com> | 2023-07-20 00:28:49 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-07-27 09:44:41 +0300 |
| commit | 7b52a78a91fd3145909d5cc7ec3c727061e4ad21 (patch) | |
| tree | 7e9a9df50a1dfdd2b86bb08c0ee0a043b5dd0846 | |
| parent | 1d4f2c4be1365afdb1411884d71bf3b04a2c9b1e (diff) | |
| download | linux-7b52a78a91fd3145909d5cc7ec3c727061e4ad21.tar.xz | |
tcp: annotate data-races around tp->keepalive_time
[ Upstream commit 4164245c76ff906c9086758e1c3f87082a7f5ef5 ]
do_tcp_getsockopt() reads tp->keepalive_time while another cpu
might change its value.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230719212857.3943972-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | include/net/tcp.h | 7 | ||||
| -rw-r--r-- | net/ipv4/tcp.c | 3 |
2 files changed, 7 insertions, 3 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h index e231101e5001..92de7c049f19 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1459,9 +1459,12 @@ static inline int keepalive_intvl_when(const struct tcp_sock *tp) static inline int keepalive_time_when(const struct tcp_sock *tp) { struct net *net = sock_net((struct sock *)tp); + int val; - return tp->keepalive_time ? : - READ_ONCE(net->ipv4.sysctl_tcp_keepalive_time); + /* Paired with WRITE_ONCE() in tcp_sock_set_keepidle_locked() */ + val = READ_ONCE(tp->keepalive_time); + + return val ? : READ_ONCE(net->ipv4.sysctl_tcp_keepalive_time); } static inline int keepalive_probes(const struct tcp_sock *tp) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 39919d1436ce..053e4880d8f0 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3093,7 +3093,8 @@ int tcp_sock_set_keepidle_locked(struct sock *sk, int val) if (val < 1 || val > MAX_TCP_KEEPIDLE) return -EINVAL; - tp->keepalive_time = val * HZ; + /* Paired with WRITE_ONCE() in keepalive_time_when() */ + WRITE_ONCE(tp->keepalive_time, val * HZ); if (sock_flag(sk, SOCK_KEEPOPEN) && !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { u32 elapsed = keepalive_time_elapsed(tp); |