Thread: pgsql: Fix resource leak when a FDW's ForeignAsyncRequest function fail
pgsql: Fix resource leak when a FDW's ForeignAsyncRequest function fail
From
Heikki Linnakangas
Date:
Fix resource leak when a FDW's ForeignAsyncRequest function fails If an error is thrown after calling CreateWaitEventSet(), the memory of a WaitEventSet is free'd as it's allocated in the short-lived memory context, but the file descriptor (on epoll- or kqueue-based systems) or handles (on Windows) that it contains are leaked. Use PG_TRY-FINALLY to ensure it gets freed. (On master, I will apply a better fix, using ResourceOwners to track the WaitEventSet, but that's not backpatchable.) The added test doesn't check for leaking resources, so it passed even before this commit. But at least it covers the code path. In the passing, fix misleading comment on what the 'nevents' argument to WaitEventSetWait means. Report by Alexander Lakhin, analysis and suggestion for the fix by Tom Lane. Fixes bug #17828. Backpatch to v14 where async execution was introduced, but master gets a different fix. Discussion: https://www.postgresql.org/message-id/17828-122da8cba23236be@postgresql.org Discussion: https://www.postgresql.org/message-id/472235.1678387869@sss.pgh.pa.us Branch ------ REL_15_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/481d7d1c01c6335661dd2ccf505298e4b91ee12a Modified Files -------------- contrib/postgres_fdw/expected/postgres_fdw.out | 7 +++ contrib/postgres_fdw/sql/postgres_fdw.sql | 6 +++ src/backend/executor/nodeAppend.c | 66 +++++++++++++++----------- 3 files changed, 50 insertions(+), 29 deletions(-)