[OpenSIPS-Devel] [OpenSIPS/opensips] 75106d: Fix crash on building CANCEL requests.

[Bogdan-Andrei Iancu]

  Branch: refs/heads/2.1
  Home:   https://github.com/OpenSIPS/opensips
  Commit: 75106d9f1e2b0dbddf4eb67083154e77c9415eb7
      https://github.com/OpenSIPS/opensips/commit/75106d9f1e2b0dbddf4eb67083154e77c9415eb7
  Author: Bogdan-Andrei Iancu <bogdan at opensips.org>
  Date:   2015-05-07 (Thu, 07 May 2015)

  Changed paths:
    M modules/tm/t_cancel.c

  Log Message:
  -----------
  Fix crash on building CANCEL requests.

Avoid the race condition between building a local cancel and handling a negative reply (for the same branch, in different processes). The build_local mya use the temporary uac->reply and end up with a dnagling pointer. Anyhow, in CANCEL situation, you never have a stored reply in transaction (storing is done only during parallel forking for nagative branches - which are not to be cancelled anyhow).

(cherry picked from commit 156fba8d5eeedaa3bbb5cd89a525e1591a288123)