-
Problem report
-
Resolution: Fixed
-
Trivial
-
3.4.0alpha1
-
GNU/Linux (Debian testing)
-
Sprint 25, Sprint 26
-
2
1. Compile Zabbix with GCC 6.2 with "-fsanitize=leak" option:
$ CFLAGS="-g -O2 -fsanitize=leak" ./configure --enable-server --enable-proxy --enable-agent --enable-ipv6 --with-net-snmp --with-unixodbc --with-libxml2 --with-libcurl --with-openipmi --with-ldap --with-postgresql --with-openssl --prefix=`pwd`
2. Create an item which is checked by starting a separate thread on the agent - it could be 'vfs.fs.size', 'vfs.fs.inode' or 'vfs.dir.size'.
3. Observe in zabbix_agentd.log:
512:20170120:130846.116 Requested [vfs.dir.size[/home/zabbix34/ZBXNEXT-491/ZBXNEXT-491-2]]
512:20170120:130846.116 In zbx_execute_threaded_metric() key:'vfs.dir.size'
554:20170120:130846.118 executing in data process for key:'vfs.dir.size'
=================================================================
==554==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 24 byte(s) in 1 object(s) allocated from:
#0 0x7fd3022fdc7f in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/liblsan.so.0+0xcc7f)
#1 0x55fe97829677 in zbx_malloc2 /home/zabbix34/ZBXNEXT-491/trunk/src/libs/zbxcommon/misc.c:467
SUMMARY: LeakSanitizer: 24 byte(s) leaked in 1 allocation(s).
512:20170120:130846.168 End of zbx_execute_threaded_metric():1 'Data gathering process terminated with error.'
512:20170120:130846.168 Sending back [ZBX_NOTSUPPORTED: Data gathering process terminated with error.]
4. To confirm where the leak comes from, make a small change and recompile:
Index: src/zabbix_agent/zabbix_agentd.c
===================================================================
--- src/zabbix_agent/zabbix_agentd.c (revision 65211)
+++ src/zabbix_agent/zabbix_agentd.c (working copy)
@@ -953,7 +953,7 @@
{
zbx_thread_args_t *thread_args;
- thread_args = (zbx_thread_args_t *)zbx_malloc(NULL, sizeof(zbx_thread_args_t));
+ thread_args = (zbx_thread_args_t *)malloc(sizeof(zbx_thread_args_t));
if (FAIL == get_process_info_by_thread(i + 1, &thread_args->process_type, &thread_args->process_num))
{
5. Now in zabbix_agentd.log:
1361:20170120:132246.341 Requested [vfs.dir.size[/home/zabbix34/ZBXNEXT-491/ZBXNEXT-491-2]]
1361:20170120:132246.341 In zbx_execute_threaded_metric() key:'vfs.dir.size'
1504:20170120:132246.342 executing in data process for key:'vfs.dir.size'
=================================================================
==1504==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 96 byte(s) in 4 object(s) allocated from:
#0 0x7fbb1ca4ac7f in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/liblsan.so.0+0xcc7f)
#1 0x5641e090a140 in MAIN_ZABBIX_ENTRY /home/zabbix34/ZBXNEXT-491/trunk/src/zabbix_agent/zabbix_agentd.c:956
SUMMARY: LeakSanitizer: 96 byte(s) leaked in 4 allocation(s).
1361:20170120:132246.371 End of zbx_execute_threaded_metric():1 'Data gathering process terminated with error.'
1361:20170120:132246.371 Sending back [ZBX_NOTSUPPORTED: Data gathering process terminated with error.]