This update for libosip2 fixes the following issues:

Changes in libosip2:

- CVE-2017-7853: In libosip2 in GNU 5.0.0, a malformed SIP message can lead to a heap buffer overflow in the msg_osip_body_parse() function defined in osipparser2/osip_message_parse.c, resulting in a remote DoS. (boo#1034570)
- CVE-2016-10326: In libosip2 in GNU oSIP 4.1.0, a malformed SIP message can lead to a heap buffer overflow in the osip_body_to_str() function defined in osipparser2/osip_body.c, resulting in a remote DoS. (boo#1034571)
- CVE-2016-10325: In libosip2 in GNU oSIP 4.1.0, a malformed SIP message can lead to a heap buffer overflow in the _osip_message_to_str() function defined in osipparser2/osip_message_to_str.c, resulting in a remote DoS. (boo#1034572)
- CVE-2016-10324: In libosip2 in GNU oSIP 4.1.0, a malformed SIP message can lead to a heap buffer overflow in the osip_clrncpy() function defined in osipparser2/osip_port.c. (boo#1034574)