diff options
| author | Eric Dumazet <edumazet@google.com> | 2023-01-20 12:59:55 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-02-01 08:27:27 +0100 |
| commit | ead06e3449f222037722df08da8257ebba4d69c9 (patch) | |
| tree | 9b675240dbd74e2b045405eade8b464e963b2f7c | |
| parent | c4eb423c6b9bded9aae6aeb19960bff67cb464ff (diff) | |
netlink: annotate data races around sk_state
[ Upstream commit 9b663b5cbb15b494ef132a3c937641c90646eb73 ]
netlink_getsockbyportid() reads sk_state while a concurrent
netlink_connect() can change its value.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/netlink/af_netlink.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index e041d2df9280..011ec7d9a719 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1089,7 +1089,8 @@ static int netlink_connect(struct socket *sock, struct sockaddr *addr, return -EINVAL; if (addr->sa_family == AF_UNSPEC) { - sk->sk_state = NETLINK_UNCONNECTED; + /* paired with READ_ONCE() in netlink_getsockbyportid() */ + WRITE_ONCE(sk->sk_state, NETLINK_UNCONNECTED); /* dst_portid and dst_group can be read locklessly */ WRITE_ONCE(nlk->dst_portid, 0); WRITE_ONCE(nlk->dst_group, 0); @@ -1113,7 +1114,8 @@ static int netlink_connect(struct socket *sock, struct sockaddr *addr, err = netlink_autobind(sock); if (err == 0) { - sk->sk_state = NETLINK_CONNECTED; + /* paired with READ_ONCE() in netlink_getsockbyportid() */ + WRITE_ONCE(sk->sk_state, NETLINK_CONNECTED); /* dst_portid and dst_group can be read locklessly */ WRITE_ONCE(nlk->dst_portid, nladdr->nl_pid); WRITE_ONCE(nlk->dst_group, ffs(nladdr->nl_groups)); @@ -1165,8 +1167,8 @@ static struct sock *netlink_getsockbyportid(struct sock *ssk, u32 portid) /* Don't bother queuing skb if kernel socket has no input function */ nlk = nlk_sk(sock); - /* dst_portid can be changed in netlink_connect() */ - if (sock->sk_state == NETLINK_CONNECTED && + /* dst_portid and sk_state can be changed in netlink_connect() */ + if (READ_ONCE(sock->sk_state) == NETLINK_CONNECTED && READ_ONCE(nlk->dst_portid) != nlk_sk(ssk)->portid) { sock_put(sock); return ERR_PTR(-ECONNREFUSED); |