From 0c48eefae712c2fd91480346a07a1a9cd0f9470b Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Sun, 4 Jul 2021 12:02:43 -0700 Subject: [PATCH] sock_map: Lift socket state restriction for datagram sockets TCP and other connection oriented sockets have accept() for each incoming connection on the server side, hence they can just insert those fd's from accept() to sockmap, which are of course established. Now with datagram sockets begin to support sockmap and redirection, the restriction is no longer applicable to them, as they have no accept(). So we have to lift this restriction for them. This is fine, because inside bpf_sk_redirect_map() we still have another socket status check, sock_map_redirect_allowed(), as a guard. This also means they do not have to be removed from sockmap when disconnecting. Signed-off-by: Cong Wang Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20210704190252.11866-3-xiyou.wangcong@gmail.com --- net/core/sock_map.c | 21 +-------------------- net/ipv4/udp_bpf.c | 1 - .../selftests/bpf/prog_tests/sockmap_listen.c | 8 +++++--- 3 files changed, 6 insertions(+), 24 deletions(-) diff --git a/net/core/sock_map.c b/net/core/sock_map.c index 60decd6420ca..3c427e7e6df9 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -211,8 +211,6 @@ out: return psock; } -static bool sock_map_redirect_allowed(const struct sock *sk); - static int sock_map_link(struct bpf_map *map, struct sock *sk) { struct sk_psock_progs *progs = sock_map_progs(map); @@ -223,13 +221,6 @@ static int sock_map_link(struct bpf_map *map, struct sock *sk) struct sk_psock *psock; int ret; - /* Only sockets we can redirect into/from in BPF need to hold - * refs to parser/verdict progs and have their sk_data_ready - * and sk_write_space callbacks overridden. - */ - if (!sock_map_redirect_allowed(sk)) - goto no_progs; - stream_verdict = READ_ONCE(progs->stream_verdict); if (stream_verdict) { stream_verdict = bpf_prog_inc_not_zero(stream_verdict); @@ -264,7 +255,6 @@ static int sock_map_link(struct bpf_map *map, struct sock *sk) } } -no_progs: psock = sock_map_psock_get_checked(sk); if (IS_ERR(psock)) { ret = PTR_ERR(psock); @@ -527,12 +517,6 @@ static bool sk_is_tcp(const struct sock *sk) sk->sk_protocol == IPPROTO_TCP; } -static bool sk_is_udp(const struct sock *sk) -{ - return sk->sk_type == SOCK_DGRAM && - sk->sk_protocol == IPPROTO_UDP; -} - static bool sock_map_redirect_allowed(const struct sock *sk) { if (sk_is_tcp(sk)) @@ -550,10 +534,7 @@ static bool sock_map_sk_state_allowed(const struct sock *sk) { if (sk_is_tcp(sk)) return (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_LISTEN); - else if (sk_is_udp(sk)) - return sk_hashed(sk); - - return false; + return true; } static int sock_hash_update_common(struct bpf_map *map, void *key, diff --git a/net/ipv4/udp_bpf.c b/net/ipv4/udp_bpf.c index 45b8782aec0c..cb1d113ce6fd 100644 --- a/net/ipv4/udp_bpf.c +++ b/net/ipv4/udp_bpf.c @@ -112,7 +112,6 @@ static struct proto udp_bpf_prots[UDP_BPF_NUM_PROTS]; static void udp_bpf_rebuild_protos(struct proto *prot, const struct proto *base) { *prot = *base; - prot->unhash = sock_map_unhash; prot->close = sock_map_close; prot->recvmsg = udp_bpf_recvmsg; } diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c index 515229f24a93..b8934ae694e5 100644 --- a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c @@ -351,9 +351,11 @@ static void test_insert_opened(int family, int sotype, int mapfd) errno = 0; value = s; err = bpf_map_update_elem(mapfd, &key, &value, BPF_NOEXIST); - if (!err || errno != EOPNOTSUPP) - FAIL_ERRNO("map_update: expected EOPNOTSUPP"); - + if (sotype == SOCK_STREAM) { + if (!err || errno != EOPNOTSUPP) + FAIL_ERRNO("map_update: expected EOPNOTSUPP"); + } else if (err) + FAIL_ERRNO("map_update: expected success"); xclose(s); } -- 2.11.0