From e1dc0615c6b08ef36414f08c011965b8fb56198b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 12 Sep 2023 09:17:24 +0000 Subject: udp: move udp->gro_enabled to udp->udp_flags syzbot reported that udp->gro_enabled can be read locklessly. Use one atomic bit from udp->udp_flags. Fixes: e20cf8d3f1f7 ("udp: implement GRO for plain UDP sockets.") Reported-by: syzbot Signed-off-by: Eric Dumazet Reviewed-by: Willem de Bruijn Signed-off-by: Paolo Abeni --- net/ipv4/udp.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'net/ipv4/udp.c') diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index cb32826a1db2..1debc10a0f02 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1868,7 +1868,7 @@ try_again: (struct sockaddr *)sin); } - if (udp_sk(sk)->gro_enabled) + if (udp_test_bit(GRO_ENABLED, sk)) udp_cmsg_recv(msg, sk, skb); if (inet_cmsg_flags(inet)) @@ -2713,7 +2713,7 @@ int udp_lib_setsockopt(struct sock *sk, int level, int optname, /* when enabling GRO, accept the related GSO packet type */ if (valbool) udp_tunnel_encap_enable(sk->sk_socket); - up->gro_enabled = valbool; + udp_assign_bit(GRO_ENABLED, sk, valbool); up->accept_udp_l4 = valbool; release_sock(sk); break; @@ -2803,7 +2803,7 @@ int udp_lib_getsockopt(struct sock *sk, int level, int optname, break; case UDP_GRO: - val = up->gro_enabled; + val = udp_test_bit(GRO_ENABLED, sk); break; /* The following two cannot be changed on UDP sockets, the return is -- cgit v1.2.3