5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet edumazet@google.com
[ Upstream commit eef00a82c568944f113f2de738156ac591bbd5cd ]
inet_recv_error() is called without holding the socket lock.
IPv6 socket could mutate to IPv4 with IPV6_ADDRFORM socket option and trigger a KCSAN warning.
Fixes: f4713a3dfad0 ("net-timestamp: make tcp_recvmsg call ipv6_recv_error for AF_INET6 socks") Signed-off-by: Eric Dumazet edumazet@google.com Cc: Willem de Bruijn willemb@google.com Reviewed-by: Willem de Bruijn willemb@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/af_inet.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index a3f77ac173b5..e05cdc608850 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1572,10 +1572,12 @@ EXPORT_SYMBOL(inet_current_timestamp);
int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) { - if (sk->sk_family == AF_INET) + unsigned int family = READ_ONCE(sk->sk_family); + + if (family == AF_INET) return ip_recv_error(sk, msg, len, addr_len); #if IS_ENABLED(CONFIG_IPV6) - if (sk->sk_family == AF_INET6) + if (family == AF_INET6) return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len); #endif return -EINVAL;