libssh2_channel_forward_listen_ex发送全局请求包失败求助

我正在用libssh2实现本地端口转发，环境及现状如下：

• 服务器为运行OpenSSH的Docker容器，部署了TCP回显服务，采用密码登录方式
• 可正常通过ssh命令登录服务器，也能通过ssh -L 7894:127.0.0.1:1794 server实现端口转发，本地执行nc 127.0.0.1 7894能正常触发回显服务响应

但自行编写的libssh2应用程序调用libssh2_channel_forward_listen_ex时失败，错误信息为：Unable to send global-request packet for forward listen request，错误码errno为-7。

OpenSSH调试日志（尾部内容） #

2022-10-26 13:48:02.221353473  Accepted password for linuxserver.io from 172.17.0.1 port 59038 ssh2
2022-10-26 13:48:02.221354712  debug1: monitor_child_preauth: user linuxserver.io authenticated by privileged process
2022-10-26 13:48:02.221355826  debug3: mm_get_keystate: Waiting for new keys
2022-10-26 13:48:02.221356944  debug3: mm_request_receive_expect: entering, type 26
2022-10-26 13:48:02.221358009  debug3: mm_request_receive: entering
2022-10-26 13:48:02.225893485  debug3: mm_get_keystate: GOT new keys
2022-10-26 13:48:02.226000913  debug3: mm_auth_password: user authenticated [preauth]
2022-10-26 13:48:02.226070905  debug3: user_specific_delay: user specific delay 0.000ms [preauth]
2022-10-26 13:48:02.226164806  debug3: ensure_minimum_time_since: elapsed 3.936ms, delaying 4.139ms (requested 8.076ms) [preauth]
2022-10-26 13:48:02.226271865  debug3: send packet: type 52 [preauth]
2022-10-26 13:48:02.226375237  debug3: mm_request_send: entering, type 26 [preauth]
2022-10-26 13:48:02.226423116  debug3: mm_send_keystate: Finished sending state [preauth]
2022-10-26 13:48:02.226827341  debug1: monitor_read_log: child log fd closed
2022-10-26 13:48:02.227487840  debug3: ssh_sandbox_parent_finish: finished
2022-10-26 13:48:02.228021181  User child is on pid 266
2022-10-26 13:48:02.228839803  debug3: monitor_apply_keystate: packet_set_state
2022-10-26 13:48:02.229331154  debug2: ssh_set_newkeys: mode 0
2022-10-26 13:48:02.229740053  debug1: rekey in after 4294967296 blocks
2022-10-26 13:48:02.230150994  debug2: ssh_set_newkeys: mode 1
2022-10-26 13:48:02.230567267  debug1: rekey out after 4294967296 blocks
2022-10-26 13:48:02.231008444  debug1: ssh_packet_set_postauth: called
2022-10-26 13:48:02.231441309  debug3: ssh_packet_set_state: done
2022-10-26 13:48:02.231937248  debug3: notify_hostkeys: key 0: ssh-rsa SHA256:/7FFzlIP6gEuh52lzVrSDATTQFj4wnH5ScMtaH+NpHM
2022-10-26 13:48:02.232015182  debug3: notify_hostkeys: key 1: ecdsa-sha2-nistp256 SHA256:njZFCzAT2OFVE0n/kJ6YdOVCF7iPGjyZmy5Lr+3DE2E
2022-10-26 13:48:02.232069432  debug3: notify_hostkeys: key 2: ssh-ed25519 SHA256:YP702pqTQF410dCkQgOsWD/pz+MXoVNv5EzQnxklFD4
2022-10-26 13:48:02.232091834  debug3: notify_hostkeys: sent 3 hostkeys
2022-10-26 13:48:02.232108621  debug3: send packet: type 80
2022-10-26 13:48:02.232146882  debug1: active: key options: agent-forwarding port-forwarding pty user-rc x11-forwarding
2022-10-26 13:48:02.232166314  debug1: Entering interactive session for SSH2.
2022-10-26 13:48:02.232183856  debug1: server_init_dispatch
2022-10-26 13:48:02.232393938  Connection closed by 172.17.0.1 port 59038
2022-10-26 13:48:02.232422452  debug1: do_cleanup
2022-10-26 13:48:02.232439029  Transferred: sent 2096, received 1368 bytes
2022-10-26 13:48:02.232453748  Closing connection to 172.17.0.1 port 59038
2022-10-26 13:48:02.232524366  debug3: mm_request_send: entering, type 50
2022-10-26 13:48:02.232582535  debug3: mm_request_receive: entering
2022-10-26 13:48:02.232583894  debug3: monitor_read: checking request 50
2022-10-26 13:48:02.232585103  debug3: mm_answer_term: tearing down sessions

libssh2调试输出 #

[libssh2] 0.225733 Conn: Requesting tcpip-forward session for 127.0.0.1:54814
[2022-10-26 08:48:02.226] [error] Failed to start the local-forward listener: Unable to send global-request packet for forward listen request (-7)

=> libssh2_transport_write plain (36 bytes)
0000: 50 00 00 00 0D 74 63 70  69 70 2D 66 6F 72 77 61 : P....tcpip-forwa
0010: 72 64 01 00 00 00 09 31  32 37 2E 30 2E 30 2E 31 : rd.....127.0.0.1
0020: 00 00 D6 1E                                      : ....
[libssh2] 0.225763 Socket: Error sending 80 bytes: 9
[libssh2] 0.225765 Failure Event: -7 - Unable to send global-request packet for forward listen request
[libssh2] 0.225935 Transport: Disconnecting: reason=11, desc=Shutdown SSH session, lang=
=> libssh2_transport_write plain (33 bytes)
0000: 01 00 00 00 0B 00 00 00  14 53 68 75 74 64 6F 77 : .........Shutdow
0010: 6E 20 53 53 48 20 73 65  73 73 69 6F 6E 00 00 00 : n SSH session...
0020: 00                                               : .
=> libssh2_transport_write plain2 (0 bytes)
[libssh2] 0.225977 Socket: Error sending 80 bytes: 9
[libssh2] 0.225979 Transport: Freeing session resource
[libssh2] 0.225985 Transport: Extra packets left 0
[libssh2] 0.225987 Transport: unable to reset socket's blocking state

Process finished with exit code 1

更新 #

排查发现Socket: Error sending 80 bytes: 9为超时错误，但添加libssh2_session_set_timeout(session, 0);后问题仍未解决，求帮忙排查。

内容的提问来源于stack exchange，提问作者Daniel