### Description

When using cfg_get in async_workers, the values cannot be retrieved. You either get a 'soft' fail with kamailio failing to assign the value, or you get a 'hard' fail and kamailio core dumps. The difference in behaviour appears to be determined by where the cfg variable is defined. If its defined in kamailio.cfg, you get a soft failure. If its defined in a cfg file which you included, you get a hard failure.

### Troubleshooting

Tried MANY combinations of setting the variable in different places, different length of variable names, including different characters.

#### Reproduction

test_crash.cfg

``` #!KAMAILIO

debug=8 fork=yes children=1 async_workers=1

listen=udp:127.0.0.1:12345

loadmodule "kex.so" loadmodule "mi_fifo.so" loadmodule "tm.so" loadmodule "tmx.so" loadmodule "sl.so" loadmodule "uac.so" loadmodule "rr.so" loadmodule "pv.so" loadmodule "async.so" loadmodule "xlog.so"

modparam("mi_fifo", "fifo_name", "./kamailio.fifo")

include_file "test_crash_included.cfg"

info.var = 1 desc "Info Variable"

request_route { if(@cfg_get.info.var == 1) { # This gets printed xlog("Variable is 1 in request route\n"); } if(@cfg_get.info.var_from_other_file == 1) { # This gets printed xlog("Variable from other file is 1 in request route\n"); }

if(t_newtran()) { async_task_route("ASYNC_REQUEST_ROUTE"); } exit; }

route[ASYNC_REQUEST_ROUTE] { if(@cfg_get.info.var == 1) { # This doesn't get printed xlog("Variable is 1 in async route\n"); } else { # This assignment fails with error: # 5(19705) ERROR: <core> [lvalue.c:405]: lval_assign(): assignment failed at pos: (48,39-48,39) $var(test) = @cfg_get.info.var; xlog("Variable is $var(test)\n"); } # Crash occurs on this line if(@cfg_get.info.var_from_other_file == 1) { xlog("Variable from other file is 1 in async route\n"); }

t_reply("200", "OK"); } ```

test_crash_included.cfg

``` #!KAMAILIO

info.var_from_other_file = 1 desc "Var from other file"

```

#### Debugging Data

<!-- If you got a core dump, use gdb to extract troubleshooting data - full backtrace, local variables and the list of the code at the issue location.

gdb /path/to/kamailio /path/to/corefile bt full info locals list

If you are familiar with gdb, feel free to attach more of what you consider to be relevant. -->

``` (paste your debugging data here) ```

#### Log Messages

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``` (paste your log messages here) ```

#### SIP Traffic

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``` (paste your sip traffic here) ```

### Possible Solutions

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### Additional Information

* **Kamailio Version** - output of `kamailio -v`

``` version: kamailio 4.4.2 (x86_64/linux) 892ad6 flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144, MAX_LISTEN 16, MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: 892ad6 compiled on 18:41:47 Dec 4 2017 with x86_64-unknown-linux-gnu-gcc 4.9.4 ```

* **Operating System**:

<!-- Details about the operating system, the type: Linux (e.g.,: Debian 8.4, Ubuntu 16.04, CentOS 7.1, ...), MacOS, xBSD, Solaris, ...; Kernel details (output of `uname -a`) -->

``` Linux ip-172-31-126-249 4.4.23-31.54.amzn1.x86_64 #1 SMP Tue Oct 18 22:02:09 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux ```