Fix edge-case resource leaks in PL/Python error reporting. PLy_elog_impl and its subroutine PLy_traceback intended to avoid leaking any PyObject reference counts, but their coverage of the matter was sadly incomplete. In particular, out-of-memory errors in most of the string-construction subroutines could lead to reference count leaks, because those calls were outside the PG_TRY blocks responsible for dropping reference counts.
Fix by (a) adjusting the scopes of the PG_TRY blocks, and (b) moving the responsibility for releasing the reference counts of the traceback-stack objects to PLy_elog_impl. This requires some additional "volatile" markers, but not too many. In passing, fix an ancient thinko: use of the "e_module_o" PyObject was guarded by "if (e_type_s)", where surely "if (e_module_o)" was meant. This would only have visible consequences if the "__name__" attribute were present but the "__module__" attribute wasn't, which apparently never happens; but someday it might. Rearranging the PG_TRY blocks requires indenting a fair amount of code one more tab stop, which I'll do separately for clarity. Author: Tom Lane <t...@sss.pgh.pa.us> Discussion: https://postgr.es/m/2954090.1748723...@sss.pgh.pa.us Backpatch-through: 13 Branch ------ REL_15_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/b56a92651ad43fbea087f7659f8d190825be80e2 Modified Files -------------- src/pl/plpython/plpy_elog.c | 105 +++++++++++++++++++++++--------------------- 1 file changed, 55 insertions(+), 50 deletions(-)
