### Description Applying a simple `{s.prefixes}` transformation on a variable with an empty value crashes Kamailio. It is not specific to a particular SIP message being processed. ### Troubleshooting #### Reproduction ``` request_route { $var(empty) = ""; $var(result) = $(var(empty){s.prefixes}); drop; } ``` #### Debugging Data ``` (paste your debugging data here) ``` #### Log Messages ``` kernel: [27707776.714159] kamailio[13060]: segfault at 562232762ff0 ip 00007f82a1e76391 sp 00007ffc3bc7fcd8 error 4 in libc-2.24.so[7f82a1d4d000+195000] ``` #### SIP Traffic Any SIP traffic will do, as long as this particular scenario is hit, for whatever reason. Could be buggy business logic. ### Possible Solutions The only thing I could think of is to place the transformation inside an `if` statement which checks for an empty value of the variable the `{s.prefixes]` transformation is being applied to. ### Additional Information I've tested this with Kamailio 5.1 and 5.4, and both have this issue. * **Kamailio Version** - output of `kamailio -v` ``` version: kamailio 5.4.0 (x86_64/linux) version: kamailio 5.1.10 (x86_64/linux) ``` * **Operating System**: ``` Kamailio 5.1.10 -> Debian GNU/Linux 9.13 (stretch) Kamailio 5.4.0 -> Debian GNU/Linux 9.8 (stretch) ``` -- You are receiving this because you are subscribed to this thread. Reply to this email directly or view it on GitHub: https://github.com/kamailio/kamailio/issues/2467