[#ZBX-8951] agent crashes on net.if.discovery

I have been implementing Zabbix in my organization and found/fixed a bug in agent version 2.4.0. The net.if.discovery item sometimes crashes the agent on HP-UX 11.31. I found the problem in src/libs/
zbxsysinfo/hpux/net.c

zbx_json_init(&j, ZBX_JSON_STAT_BUF_LEN);
zbx_json_addarray(&j, ZBX_PROTO_TAG_DATA);

What was happening was the buffer_size member of the zbx_json struct that were being passed to these functions was returning unusual values. After further digging I found that the buffer_size member was never assigned a value, so whatever was at that memory address was being used in the calls to the memory allocation functions. I included a block of code below that shows my change. I inserted lines 187 and 188.

#if HPUX_VERSION < 1131
   167        if_list = zbx_malloc(if_list, if_list_alloc);
   168        *if_list = '\0';
   169   
   170        if (FAIL == get_if_names(&if_list, &if_list_alloc, &if_list_offset))
   171        {
   172            SET_MSG_RESULT(result, zbx_strdup(NULL, "Cannot obtain network interface information."));
   173            zbx_free(if_list);
   174            return SYSINFO_RET_FAIL;
   175        }
   176   
   177        zbx_json_init(&j, ZBX_JSON_STAT_BUF_LEN);
   178   
   179        zbx_json_addarray(&j, ZBX_PROTO_TAG_DATA);
   180   
   181        if_name = if_list;
   182   
   183        while (NULL != if_name)
   184        {
   185            if (NULL != (if_name_end = strchr(if_name, ZBX_IF_SEP)))
   186                *if_name_end = '\0';
   187    #else
   188        zbx_json_init(&j, ZBX_JSON_STAT_BUF_LEN); /*I added this*/
   189        zbx_json_addarray(&j, ZBX_PROTO_TAG_DATA); /*I added this*/
   190        for (ni = if_nameindex(), i = 0; 0 != ni[i].if_index; i++)
   191        {
   192            if_name = ni[i].if_name;
   193    #endif
   194            zbx_json_addobject(&j, NULL);
   195            zbx_json_addstring(&j, "{#IFNAME}", if_name, ZBX_JSON_TYPE_STRING);
   196            zbx_json_close(&j);
   197    #if HPUX_VERSION < 1131
   198            if (NULL != if_name_end)
   199            {
   200                *if_name_end = ZBX_IF_SEP;
   201                if_name = if_name_end + 1;
   202            }
   203            else
   204                if_name = NULL;
   205    #endif

$ svn log -c 45668 ------------------------------------------------------------------------ r45668 | asaveljevs | 2014-05-20 14:13:39 +0300 (Tue, 20 May 2014) | 1 line ...GI..PS. [ZBXNEXT-2203] added information on the reason items become not supported ------------------------------------------------------------------------

[ZBX-8951] agent crashes on net.if.discovery Created: 2014 Oct 24 Updated: 2017 May 30 Resolved: 2014 Oct 29
Status:	Closed
Project:	ZABBIX BUGS AND ISSUES
Component/s:	Agent (G)
Affects Version/s:	2.4.0, 2.4.1
Fix Version/s:	2.4.2rc1, 2.5.0

[ZBX-8951] agent crashes on net.if.discovery Created: 2014 Oct 24 Updated: 2017 May 30 Resolved: 2014 Oct 29