From: John Fastabend john.fastabend@gmail.com
[ Upstream commit 5607fff303636d48b88414c6be353d9fed700af2 ]
After this patch we only allow socks that are in ESTABLISHED state or are being added via a sock_ops event that is transitioning into an ESTABLISHED state. By allowing sock_ops events we allow users to manage sockmaps directly from sock ops programs. The two supported sock_ops ops are BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB and BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB.
Similar to TLS ULP this ensures sk_user_data is correct.
Reported-by: Eric Dumazet edumazet@google.com Fixes: 1aa12bdf1bfb ("bpf: sockmap, add sock close() hook to remove socks") Signed-off-by: John Fastabend john.fastabend@gmail.com Acked-by: Yonghong Song yhs@fb.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- kernel/bpf/sockmap.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-)
diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index ed707b21d152..0d829e71024b 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -2092,8 +2092,12 @@ static int sock_map_update_elem(struct bpf_map *map, return -EINVAL; }
+ /* ULPs are currently supported only for TCP sockets in ESTABLISHED + * state. + */ if (skops.sk->sk_type != SOCK_STREAM || - skops.sk->sk_protocol != IPPROTO_TCP) { + skops.sk->sk_protocol != IPPROTO_TCP || + skops.sk->sk_state != TCP_ESTABLISHED) { fput(socket->file); return -EOPNOTSUPP; } @@ -2448,6 +2452,16 @@ static int sock_hash_update_elem(struct bpf_map *map, return -EINVAL; }
+ /* ULPs are currently supported only for TCP sockets in ESTABLISHED + * state. + */ + if (skops.sk->sk_type != SOCK_STREAM || + skops.sk->sk_protocol != IPPROTO_TCP || + skops.sk->sk_state != TCP_ESTABLISHED) { + fput(socket->file); + return -EOPNOTSUPP; + } + lock_sock(skops.sk); preempt_disable(); rcu_read_lock(); @@ -2536,10 +2550,22 @@ const struct bpf_map_ops sock_hash_ops = { .map_release_uref = sock_map_release, };
+static bool bpf_is_valid_sock_op(struct bpf_sock_ops_kern *ops) +{ + return ops->op == BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB || + ops->op == BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB; +} BPF_CALL_4(bpf_sock_map_update, struct bpf_sock_ops_kern *, bpf_sock, struct bpf_map *, map, void *, key, u64, flags) { WARN_ON_ONCE(!rcu_read_lock_held()); + + /* ULPs are currently supported only for TCP sockets in ESTABLISHED + * state. This checks that the sock ops triggering the update is + * one indicating we are (or will be soon) in an ESTABLISHED state. + */ + if (!bpf_is_valid_sock_op(bpf_sock)) + return -EOPNOTSUPP; return sock_map_ctx_update_elem(bpf_sock, map, key, flags); }
@@ -2558,6 +2584,9 @@ BPF_CALL_4(bpf_sock_hash_update, struct bpf_sock_ops_kern *, bpf_sock, struct bpf_map *, map, void *, key, u64, flags) { WARN_ON_ONCE(!rcu_read_lock_held()); + + if (!bpf_is_valid_sock_op(bpf_sock)) + return -EOPNOTSUPP; return sock_hash_ctx_update_elem(bpf_sock, map, key, flags); }