Wang Yufen wrote:
> In tcp_bpf_send_verdict(), if msg has more data after
> tcp_bpf_sendmsg_redir():
>
> tcp_bpf_send_verdict()
> tosend = msg->sg.size //msg->sg.size = 22220
> case __SK_REDIRECT:
> sk_msg_return() //uncharged msg->sg.size(22220) sk->sk_forward_alloc
> tcp_bpf_sendmsg_redir() //after tcp_bpf_sendmsg_redir, msg->sg.size=11000
> goto more_data;
> tosend = msg->sg.size //msg->sg.size = 11000
> case __SK_REDIRECT:
> sk_msg_return() //uncharged msg->sg.size(11000) to sk->sk_forward_alloc
>
> The msg->sg.size(11000) has been uncharged twice, to fix we can charge the
> remaining msg->sg.size before goto more data.
>
> This issue can cause the following info:
> WARNING: CPU: 0 PID: 9860 at net/core/stream.c:208 sk_stream_kill_queues+0xd4/0x1a0
> Call Trace:
> <TASK>
> inet_csk_destroy_sock+0x55/0x110
> __tcp_close+0x279/0x470
> tcp_close+0x1f/0x60
> inet_release+0x3f/0x80
> __sock_release+0x3d/0xb0
> sock_close+0x11/0x20
> __fput+0x92/0x250
> task_work_run+0x6a/0xa0
> do_exit+0x33b/0xb60
> do_group_exit+0x2f/0xa0
> get_signal+0xb6/0x950
> arch_do_signal_or_restart+0xac/0x2a0
> ? vfs_write+0x237/0x290
> exit_to_user_mode_prepare+0xa9/0x200
> syscall_exit_to_user_mode+0x12/0x30
> do_syscall_64+0x46/0x80
> entry_SYSCALL_64_after_hwframe+0x44/0xae
> </TASK>
>
> WARNING: CPU: 0 PID: 2136 at net/ipv4/af_inet.c:155 inet_sock_destruct+0x13c/0x260
> Call Trace:
> <TASK>
> __sk_destruct+0x24/0x1f0
> sk_psock_destroy+0x19b/0x1c0
> process_one_work+0x1b3/0x3c0
> worker_thread+0x30/0x350
> ? process_one_work+0x3c0/0x3c0
> kthread+0xe6/0x110
> ? kthread_complete_and_exit+0x20/0x20
> ret_from_fork+0x22/0x30
> </TASK>
>
> Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
> Signed-off-by: Wang Yufen <wangyufen@xxxxxxxxxx>
> ---
LGTM also fixes another charge error when going through the error path with
apply set where it looks like we would have left some bytes charged to the
socket.
Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>
