out_stackdriver: fixed a memory leak (CID 508244)

[leonardo-albertovich]

No description provided.

[leonardo-albertovich]

@igorpeshansky I performed a cursory inspection to validate (and expand) the findings and patched the leaks I could confirm, however I'm not familiar with the stackdriver plugin and would greatly appreciate if someone from the team could verify this PR.

Additionally, It seems that source_location_file and source_location_function are also leaked, could you verify this?

[braydonk]

Thanks for fixing this. These cleanups were missed when I reviewed the PRs by external contributors, I should have caught them.

source_location_file and source_location_function don't look like they should be leaked, at least a look at the code indicates they should be cleaned up.

They are allocated here (not guarded by any condition):

fluent-bit/plugins/out_stackdriver/stackdriver.c

Lines 2328 to 2331 in d873502

	source_location_file = flb_sds_create("");
	source_location_line = 0;
	source_location_function = flb_sds_create("");
	source_location_extra_size = 0;

Then cleaned up here (also not guarded by any conditions):

fluent-bit/plugins/out_stackdriver/stackdriver.c

Lines 2461 to 2462 in d873502

	flb_sds_destroy(source_location_file);
	flb_sds_destroy(source_location_function);

[leonardo-albertovich]

I meant they would be leaked if this code path was taken.

[braydonk]

I didn't notice that, yeah you're right that's a leak.