plugin_proxy: destroy used buffer on exit

[nokute78]

plugin_proxy leaks several times. I fixed.

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Testing
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• Example configuration file for the change
• [N/A] Debug log output from testing the change

• Attached Valgrind output that shows no leaks or memory corruption was found

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Configuration file

It is same as #3863 (comment)

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[nokute78]

The below is an output of valgrind current master

Leak of name and description

30e0bab is to fix.
The name and description are should not use heap since almost plugin uses const char*.

==9145== 8 bytes in 1 blocks are definitely lost in loss record 3 of 17
==9145==    at 0x483B7F3: malloc (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
==9145==    by 0x1D4937: flb_malloc (flb_mem.h:62)
==9145==    by 0x1D4A00: flb_strdup (flb_str.h:37)
==9145==    by 0x1D4D74: flb_proxy_register_output (flb_plugin_proxy.c:107)
==9145==    by 0x1D4EF6: flb_plugin_proxy_register (flb_plugin_proxy.c:181)
==9145==    by 0x1D50AB: flb_plugin_proxy_create (flb_plugin_proxy.c:248)
==9145==    by 0x1C66CF: flb_plugin_load_router (flb_plugin.c:311)
==9145==    by 0x1C694F: flb_plugin_load_config_file (flb_plugin.c:379)
==9145==    by 0x1B2CD4: flb_config_set_property (flb_config.c:515)
==9145==    by 0x192696: flb_service_conf (fluent-bit.c:759)
==9145==    by 0x193356: flb_main (fluent-bit.c:1142)
==9145==    by 0x193533: main (fluent-bit.c:1221)
==9145== 
==9145== 11 bytes in 1 blocks are definitely lost in loss record 4 of 17
==9145==    at 0x483B7F3: malloc (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
==9145==    by 0x1D4937: flb_malloc (flb_mem.h:62)
==9145==    by 0x1D4A00: flb_strdup (flb_str.h:37)
==9145==    by 0x1D4D8C: flb_proxy_register_output (flb_plugin_proxy.c:108)
==9145==    by 0x1D4EF6: flb_plugin_proxy_register (flb_plugin_proxy.c:181)
==9145==    by 0x1D50AB: flb_plugin_proxy_create (flb_plugin_proxy.c:248)
==9145==    by 0x1C66CF: flb_plugin_load_router (flb_plugin.c:311)
==9145==    by 0x1C694F: flb_plugin_load_config_file (flb_plugin.c:379)
==9145==    by 0x1B2CD4: flb_config_set_property (flb_config.c:515)
==9145==    by 0x192696: flb_service_conf (fluent-bit.c:759)
==9145==    by 0x193356: flb_main (fluent-bit.c:1142)
==9145==    by 0x193533: main (fluent-bit.c:1221)

Leak of flb_plugin_proxy_def

1a359fd is to fix.
The struct is not saved as a member of plugin instance.
I added it to flb_plugin_proxy and released on destructor.

==9145== 51 (32 direct, 19 indirect) bytes in 1 blocks are definitely lost in loss record 9 of 17
==9145==    at 0x483B7F3: malloc (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
==9145==    by 0x1D4937: flb_malloc (flb_mem.h:62)
==9145==    by 0x1D4E59: flb_plugin_proxy_register (flb_plugin_proxy.c:152)
==9145==    by 0x1D50AB: flb_plugin_proxy_create (flb_plugin_proxy.c:248)
==9145==    by 0x1C66CF: flb_plugin_load_router (flb_plugin.c:311)
==9145==    by 0x1C694F: flb_plugin_load_config_file (flb_plugin.c:379)
==9145==    by 0x1B2CD4: flb_config_set_property (flb_config.c:515)
==9145==    by 0x192696: flb_service_conf (fluent-bit.c:759)
==9145==    by 0x193356: flb_main (fluent-bit.c:1142)
==9145==    by 0x193533: main (fluent-bit.c:1221)
==9145== 

Leak of flb_plugin_proxy

6d27f38 is to fix.
Invoking destruct function.

==9145== 176 (72 direct, 104 indirect) bytes in 1 blocks are definitely lost in loss record 12 of 17
==9145==    at 0x483B7F3: malloc (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
==9145==    by 0x1D4937: flb_malloc (flb_mem.h:62)
==9145==    by 0x1D4FE0: flb_plugin_proxy_create (flb_plugin_proxy.c:226)
==9145==    by 0x1C66CF: flb_plugin_load_router (flb_plugin.c:311)
==9145==    by 0x1C694F: flb_plugin_load_config_file (flb_plugin.c:379)
==9145==    by 0x1B2CD4: flb_config_set_property (flb_config.c:515)
==9145==    by 0x192696: flb_service_conf (fluent-bit.c:759)
==9145==    by 0x193356: flb_main (fluent-bit.c:1142)
==9145==    by 0x193533: main (fluent-bit.c:1221)

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[github-actions]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[github-actions]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.