diff options
| author | Wang Yufen <wangyufen@huawei.com> | 2022-05-24 15:53:11 +0800 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2022-06-02 16:26:58 -0700 |
| commit | d8616ee2affcff37c5d315310da557a694a3303d (patch) | |
| tree | 74b7ed08e07d4f1190f140a12c5f5c9869f907cd /net | |
| parent | 200a89e3e88786b52bc1dd5f26a310c097f4c6a7 (diff) | |
bpf, sockmap: Fix sk->sk_forward_alloc warn_on in sk_stream_kill_queues
During TCP sockmap redirect pressure test, the following warning is triggered:
WARNING: CPU: 3 PID: 2145 at net/core/stream.c:205 sk_stream_kill_queues+0xbc/0xd0
CPU: 3 PID: 2145 Comm: iperf Kdump: loaded Tainted: G W 5.10.0+ #9
Call Trace:
inet_csk_destroy_sock+0x55/0x110
inet_csk_listen_stop+0xbb/0x380
tcp_close+0x41b/0x480
inet_release+0x42/0x80
__sock_release+0x3d/0xa0
sock_close+0x11/0x20
__fput+0x9d/0x240
task_work_run+0x62/0x90
exit_to_user_mode_prepare+0x110/0x120
syscall_exit_to_user_mode+0x27/0x190
entry_SYSCALL_64_after_hwframe+0x44/0xa9
The reason we observed is that:
When the listener is closing, a connection may have completed the three-way
handshake but not accepted, and the client has sent some packets. The child
sks in accept queue release by inet_child_forget()->inet_csk_destroy_sock(),
but psocks of child sks have not released.
To fix, add sock_map_destroy to release psocks.
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220524075311.649153-1-wangyufen@huawei.com
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/skmsg.c | 1 | ||||
| -rw-r--r-- | net/core/sock_map.c | 23 | ||||
| -rw-r--r-- | net/ipv4/tcp_bpf.c | 1 |
3 files changed, 25 insertions, 0 deletions
diff --git a/net/core/skmsg.c b/net/core/skmsg.c index 22b983ade0e7..7e03f96e441b 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -715,6 +715,7 @@ struct sk_psock *sk_psock_init(struct sock *sk, int node) psock->eval = __SK_NONE; psock->sk_proto = prot; psock->saved_unhash = prot->unhash; + psock->saved_destroy = prot->destroy; psock->saved_close = prot->close; psock->saved_write_space = sk->sk_write_space; diff --git a/net/core/sock_map.c b/net/core/sock_map.c index 81d4b4756a02..9f08ccfaf6da 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -1561,6 +1561,29 @@ void sock_map_unhash(struct sock *sk) } EXPORT_SYMBOL_GPL(sock_map_unhash); +void sock_map_destroy(struct sock *sk) +{ + void (*saved_destroy)(struct sock *sk); + struct sk_psock *psock; + + rcu_read_lock(); + psock = sk_psock_get(sk); + if (unlikely(!psock)) { + rcu_read_unlock(); + if (sk->sk_prot->destroy) + sk->sk_prot->destroy(sk); + return; + } + + saved_destroy = psock->saved_destroy; + sock_map_remove_links(sk, psock); + rcu_read_unlock(); + sk_psock_stop(psock, true); + sk_psock_put(sk, psock); + saved_destroy(sk); +} +EXPORT_SYMBOL_GPL(sock_map_destroy); + void sock_map_close(struct sock *sk, long timeout) { void (*saved_close)(struct sock *sk, long timeout); diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c index be3947e70fec..38550bb1b90b 100644 --- a/net/ipv4/tcp_bpf.c +++ b/net/ipv4/tcp_bpf.c @@ -540,6 +540,7 @@ static void tcp_bpf_rebuild_protos(struct proto prot[TCP_BPF_NUM_CFGS], struct proto *base) { prot[TCP_BPF_BASE] = *base; + prot[TCP_BPF_BASE].destroy = sock_map_destroy; prot[TCP_BPF_BASE].close = sock_map_close; prot[TCP_BPF_BASE].recvmsg = tcp_bpf_recvmsg; prot[TCP_BPF_BASE].sock_is_readable = sk_msg_is_readable; |