tree 71ce3f0b860e9f35424bb65ec97ad9a24c86be78
parent 6b2472a0b397c403f08a70392f5891051b608221
author Troy Lee <troy_lee@aspeedtech.com> 1629950588 +0800
committer Patrick Williams <patrick@stwcx.xyz> 1629978333 +0000

libvncserver: multithread support

obmc-ikvm runs with two seprated thread to handle connection from user
(bmcweb::kvm_websocket) and video device (libvncserver), however both
these two thread access to rfb*() API. It leads to client socket double
free issue.

cl->sock has been set to RFB_INVALID_SOCKET(-1) with first clientClose
call.
And the second call to clientClose uses -1 in FD_CLR() generates buffer
overflow.
```
obmc-ikvm[672]: 24/08/2021 08:45:11 rfbClientConnectionGone: c1=75900748
obmc-ikvm[672]: 24/08/2021 08:45:11 rfbClientConnectionGone: c1=75900748
obmc-ikvm[672]: 24/08/2021 08:45:11 rfbSendUpdateBuf: write: Broken pipe
obmc-ikvm[672]: *** buffer overflow detected ***: terminated
systemd[1]: start-ipkvm.service: Main process exited, code=dumped,
status=6/ABRT
systemd[1]: start-ipkvm.service: Failed with result 'core-dump'.
systemd[1]: start-ipkvm.service: Scheduled restart job, restart counter
is at 1.
systemd[1]: Stopped OpenBMC ipKVM daemon.
```

Signed-off-by: Troy Lee <troy_lee@aspeedtech.com>
Change-Id: I4bbe69c6d7006e44c5f4a532fb54f9ae9c9cd52b