- adds a default value for when there is no call-id in the req struct. - reported in #2803

<!-- Kamailio Pull Request Template -->

<!-- IMPORTANT: - for detailed contributing guidelines, read: https://github.com/kamailio/kamailio/blob/master/.github/CONTRIBUTING.md - pull requests must be done to master branch, unless they are backports of fixes from master branch to a stable branch - backports to stable branches must be done with 'git cherry-pick -x ...' - code is contributed under BSD for core and main components (tm, sl, auth, tls) - code is contributed GPLv2 or a compatible license for the other components - GPL code is contributed with OpenSSL licensing exception -->

#### Pre-Submission Checklist <!-- Go over all points below, and after creating the PR, tick all the checkboxes that apply --> <!-- All points should be verified, otherwise, read the CONTRIBUTING guidelines from above--> <!-- If you're unsure about any of these, don't hesitate to ask on sr-dev mailing list --> - [x] Commit message has the format required by CONTRIBUTING guide - [x] Commits are split per component (core, individual modules, libs, utils, ...) - [x] Each component has a single commit (if not, squash them into one commit) - [x] No commits to README files for modules (changes must be done to docbook files in `doc/` subfolder, the README file is autogenerated)

#### Type Of Change - [x] Small bug fix (non-breaking change which fixes an issue) - [ ] New feature (non-breaking change which adds new functionality) - [ ] Breaking change (fix or feature that would change existing functionality)

#### Checklist: <!-- Go over all points below, and after creating the PR, tick the checkboxes that apply --> - [x] PR should be backported to stable branches - [x] Tested changes locally - [x] Related to issue #2803

#### Description <!-- Describe your changes in detail -->

In some cases the callid field of the msg structure doesn't get initialized. In the case the dlg_onroute function is called with this msg and the dialog is not found a warning message is printed using the LM_WARN macro. This logger is called with a req->callid as argument and when this is null a segmentation fault happens. I added a small default value for this case. You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/2878

-- Commit Summary --

* <a href="https://github.com/kamailio/kamailio/pull/2878/commits/1a9c0c930c009e09853c9e5b0f64a9651352bffd">dialog: fix dlg_onroute</a>

-- File Changes --

M src/modules/dialog/dlg_handlers.c (10)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/2878.patch https://github.com/kamailio/kamailio/pull/2878.diff