[OpenSIPS-Devel] [OpenSIPS/opensips] 2c1c1a: Fix resuming partial msg reading on TCP

[Bogdan Andrei IANCU]

  Branch: refs/heads/3.4
  Home:   https://github.com/OpenSIPS/opensips
  Commit: 2c1c1acae5b939bcd95155ab83d142bc0b48063f
      https://github.com/OpenSIPS/opensips/commit/2c1c1acae5b939bcd95155ab83d142bc0b48063f
  Author: Bogdan-Andrei Iancu <bogdan at opensips.org>
  Date:   2023-06-30 (Fri, 30 Jun 2023)

  Changed paths:
    M net/net_tcp.c
    M net/net_tcp_proc.c
    M net/proto_tcp/proto_tcp.c
    M net/proto_tcp/tcp_common.h

  Log Message:
  -----------
  Fix resuming partial msg reading on TCP

When conn rebalancing or parallel processing is enabled for TCP, a read operation may start (partial reading) in one process and be completed in a different one. So the con_req (buffer for partial reading) must be in shm mem and also it must survive a conn release (passing the conn back to MAIN).
Many thanks to @liviuchircu for reporting and helping with the troubleshooting
This issue was found during the TCP performance tests done for the 3.4 release

(cherry picked from commit e0fe732e9c9d28c24ed6860fbd3531940978b8f9)