### Description

I just update kamailio 5.2.1 to 5.4.1. then there are some crashs from keepalive module.

### Troubleshooting 

#### Reproduction

#### Debugging Data

``` Thread 1 (Thread 0x2b4d0df90d00 (LWP 30239)): #0 0x00000000004ef1a7 in atomic_cmpxchg_int (var=0x0, old=0, new_v=1) at core/mem/../atomic/atomic_x86.h:224 #1 0x00000000004ef21a in futex_get (lock=0x0) at core/mem/../futexlock.h:99 #2 0x00000000004f339a in timer_add_safe (tl=0x2b4d13af7928, delta=8) at core/timer.c:543 #3 0x00002b4d133b32c3 in ka_add_dest (uri=0x7ffe571d1440, owner=0x7ffe571d1430, flags=0, ping_interval=3, statechanged_clb=0x0, response_clb=0x0, user_attr=0x0) at keepalive_api.c:120 #4 0x00002b4d133b95ff in ka_mod_add_destination (type=2147483649, val=0x2b4d0ed29300) at keepalive_mod.c:244 #5 0x00000000006615b8 in set_mod_param_regex (regex=0x2b4d0ed29130 "keepalive", name=0x2b4d0ed29218 "destination", type=1, val=0x2b4d0ed29300) at core/modparam.c:125 #6 0x00000000007becec in yyparse () at core/cfg.y:1842 #7 0x000000000042f216 in main (argc=5, argv=0x7ffe571d2578) at main.c:2320 #3 0x00002b4d133b32c3 in ka_add_dest (uri=0x7ffe571d1440, owner=0x7ffe571d1430, flags=0, ping_interval=3, statechanged_clb=0x0, response_clb=0x0, user_attr=0x0) at keepalive_api.c:120 120 if(timer_add(dest->timer, MS_TO_TICKS(KA_FIRST_TRY_DELAY)) < 0){ $2 = {next = 0x0, prev = 0x0, expire = 0, initial_timeout = 0, data = 0x2b4d13af7738, f = 0x2b4d133b4fbf <ka_check_timer>, flags = 0, slow_idx = 0} _uri = {user = {s = 0x0, len = 0}, passwd = {s = 0x0, len = 0}, host = {s = 0x2b4d13af783c "172.18.67.47", len = 12}, port = {s = 0x0, len = 0}, params = {s = 0x0, len = 0}, sip_params = {s = 0x0, len = 0}, headers = {s = 0x0, len = 0}, port_no = 0, proto = 0, type = SIP_URI_T, flags = (unknown: 0), transport = {s = 0x0, len = 0}, ttl = {s = 0x0, len = 0}, user_param = {s = 0x0, len = 0}, maddr = {s = 0x0, len = 0}, method = {s = 0x0, len = 0}, lr = {s = 0x0, len = 0}, r2 = {s = 0x0, len = 0}, gr = {s = 0x0, len = 0}, transport_val = {s = 0x0, len = 0}, ttl_val = {s = 0x0, len = 0}, user_param_val = { s = 0x0, len = 0}, maddr_val = {s = 0x0, len = 0}, method_val = {s = 0x0, len = 0}, lr_val = {s = 0x0, len = 0}, r2_val = {s = 0x0, len = 0}, gr_val = {s = 0x0, len = 0}} dest = 0x2b4d13af7738 hollow = 0x0 __FUNCTION__ = "ka_add_dest" #2 0x00000000004f339a in timer_add_safe (tl=0x2b4d13af7928, delta=8) at core/timer.c:543 543 LOCK_TIMER_LIST(); ret = 0 __FUNCTION__ = "timer_add_safe"

```

#### Log Messages

``` Sep 14 15:49:34 localhost kamailio: INFO: pv [pv_shv.c:60]: shvar_init_locks(): locks array size 16 Sep 14 15:49:34 localhost kernel: kamailio[30186]: segfault at 0 ip 00000000004ef1a7 sp 00007ffdd2db9170 error 6 in kamailio[400000+4ae000] ```

#### SIP Traffic

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

### Possible Solutions

### Additional Information

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

``` (paste your output here) ```

* **Operating System**:

``` Linux version 3.10.0-327.el7.x86_64 (builder@kbuilder.dev.centos.org) (gcc version 4.8.3 20140911 (Red Hat 4.8.3-9) (GCC) ) #1 SMP Thu Nov 19 22:10:57 UTC 2015 ```