The attached patch allows unprivileged clients to export from or import
to the largeobject owned by themselves.
The current security policy does not allow them to import/export any
largeobjects without any clear reason.
NOTE: Export of the largeobject means that it dumps whole of the
largeobject into a local file, so SE-PostgreSQL checks both of
db_blob:{read export} on the largeobject and file:{write} on the
local file. Import is a reversal behavior.
KaiGai Kohei
996779dfad