From eac66402d1c342f07ff38f8d631ff95eb7ad3220 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 9 Oct 2019 15:32:35 -0700 Subject: net: annotate sk->sk_rcvlowat lockless reads sock_rcvlowat() or int_sk_rcvlowat() might be called without the socket lock for example from tcp_poll(). Use READ_ONCE() to document the fact that other cpus might change sk->sk_rcvlowat under us and avoid KCSAN splats. Use WRITE_ONCE() on write sides too. Signed-off-by: Eric Dumazet Signed-off-by: Jakub Kicinski --- net/core/filter.c | 2 +- net/core/sock.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'net/core') diff --git a/net/core/filter.c b/net/core/filter.c index ed6563622ce3..a50c0b6846f2 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -4274,7 +4274,7 @@ BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock, case SO_RCVLOWAT: if (val < 0) val = INT_MAX; - sk->sk_rcvlowat = val ? : 1; + WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); break; case SO_MARK: if (sk->sk_mark != val) { diff --git a/net/core/sock.c b/net/core/sock.c index 1cf06934da50..b7c5c6ea51ba 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -974,7 +974,7 @@ set_rcvbuf: if (sock->ops->set_rcvlowat) ret = sock->ops->set_rcvlowat(sk, val); else - sk->sk_rcvlowat = val ? : 1; + WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); break; case SO_RCVTIMEO_OLD: -- cgit