5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit 6d5a12eb91224d707f8691dccb40a5719fe5466d ]
UDP_ENCAP_ESPINUDP_NON_IKE setsockopt() writes over up->encap_rcv
while other cpus read it.
Fixes: 067b207b281d ("[UDP]: Cleanup UDP encapsulation code")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reviewed-by: Willem de Bruijn <willemb@xxxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/ipv4/udp.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 198d8e07413d3..c454daa78a2f8 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -2711,10 +2711,12 @@ int udp_lib_setsockopt(struct sock *sk, int level, int optname,
case UDP_ENCAP_ESPINUDP_NON_IKE:
#if IS_ENABLED(CONFIG_IPV6)
if (sk->sk_family == AF_INET6)
- up->encap_rcv = ipv6_stub->xfrm6_udp_encap_rcv;
+ WRITE_ONCE(up->encap_rcv,
+ ipv6_stub->xfrm6_udp_encap_rcv);
else
#endif
- up->encap_rcv = xfrm4_udp_encap_rcv;
+ WRITE_ONCE(up->encap_rcv,
+ xfrm4_udp_encap_rcv);
#endif
fallthrough;
case UDP_ENCAP_L2TPINUDP:
--
2.42.0
