$OpenBSD: patch-snmplib_snmp_api_c,v 1.6 2017/10/18 13:13:43 sthen Exp $

https://support.zabbix.com/browse/ZBX-12726
https://sourceforge.net/p/net-snmp/bugs/2803/

Index: snmplib/snmp_api.c
--- snmplib/snmp_api.c.orig
+++ snmplib/snmp_api.c
@@ -1548,6 +1548,9 @@ _sess_open(netsnmp_session * in_session)
             clientaddr_save =
                 netsnmp_ds_get_string(NETSNMP_DS_LIBRARY_ID,
                                       NETSNMP_DS_LIB_CLIENT_ADDR);
+            if (NULL != clientaddr_save)
+                clientaddr_save = strdup(clientaddr_save);
+
             netsnmp_ds_set_string(NETSNMP_DS_LIBRARY_ID,
                                   NETSNMP_DS_LIB_CLIENT_ADDR,
                                   in_session->localname);
@@ -1565,9 +1568,11 @@ _sess_open(netsnmp_session * in_session)
                                                NULL);
         }
 
-        if (NULL != clientaddr_save)
+        if (NULL != clientaddr_save) {
             netsnmp_ds_set_string(NETSNMP_DS_LIBRARY_ID,
                                   NETSNMP_DS_LIB_CLIENT_ADDR, clientaddr_save);
+            free(clientaddr_save);
+        }
     }
 
     if (transport == NULL) {
