Avoid NULL dereference for ordered aggregates - #337
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Summary
chfdw_check_for_ordered_aggregate()calledget_extension_name()and thenstrcmp()without handling aggregates that are not owned by an extension. Planning an extensionless ordered-set aggregate could therefore dereference NULL and crash the backend.This change returns false for invalid or missing extension OIDs, frees the extension name, and adds a regression covering a local ordered-set aggregate. The regression confirms that the aggregate stays local while the foreign scan retrieves its input column.
Testing
pg-build-testmake installcheck REGRESS=functions