stasis/control: Fix possible deadlock with swap channel
authorGeorge Joseph <gjoseph@digium.com>
Fri, 1 Sep 2017 10:17:02 +0000 (04:17 -0600)
committerRichard Mudgett <rmudgett@digium.com>
Wed, 6 Sep 2017 18:00:49 +0000 (13:00 -0500)
commit94091c7b960aa45923036cd4d79929dcb3178cdc
tree4c045660fa8987fe3cf28a3d1bf075d0bc23c3e7
parent2857a3334aa430b81baac31bdfe0efb3871f37d4
stasis/control:  Fix possible deadlock with swap channel

If an error occurs during a bridge impart it's possible that
the "bridge_after" callback might try to run before
control_swap_channel_in_bridge has been signalled to continue.
Since control_swap_channel_in_bridge is holding the control lock
and the callback needs it, a deadlock will occur.

* control_swap_channel_in_bridge now only holds the control
  lock while it's actually modifying the control structure and
  releases it while the bridge impart is running.
* bridge_after_cb is now tolerant of impart failures.

Change-Id: Ifd239aa93955b3eb475521f61e284fcb0da2c3b3
include/asterisk/bridge_after.h
main/bridge.c
main/bridge_after.c
res/stasis/control.c