[OpenSIPS-Devel] [OpenSIPS/opensips] 2101c7: dialog: do not populate dst_leg on unmatched dlg

[Răzvan Crainea]

  Branch: refs/heads/3.4
  Home:   https://github.com/OpenSIPS/opensips
  Commit: 2101c75b63b27de6797c48724205a80fbff128ca
      https://github.com/OpenSIPS/opensips/commit/2101c75b63b27de6797c48724205a80fbff128ca
  Author: Razvan Crainea <razvan at opensips.org>
  Date:   2024-01-16 (Tue, 16 Jan 2024)

  Changed paths:
    M modules/dialog/dlg_hash.c

  Log Message:
  -----------
  dialog: do not populate dst_leg on unmatched dlg

Avoid chaning the dst_leg on unmatched dialogs, as this might lead to
inconsistent states. A common pattern is to match a dialog in state 5,
which would set a dst_leg, but then "invalidate" the dialog due to the
bad state - proceeding to a next dialog would not set the dst_leg (as it
was set by the previous match), leading to an invalid access in the
second dialog.

Credits go to NFON for reporting and providing valuable troubleshooting
information

(cherry picked from commit 224a3236cbeaeb06a897cb3beab8c3a0c3d5903f)