5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ 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@xxxxxxxxxx>
Cc: Willem de Bruijn <willemb@xxxxxxxxxx>
Reviewed-by: Willem de Bruijn <willemb@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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;
--
2.43.0
