From b27cbabee9a5980c8673c4fee4ea6f7e0c89bdbc Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Sun, 31 Jan 2021 14:04:02 +1300 Subject: [PATCH] Hold interrupts while running dsm_detach() callbacks. While cleaning up after a parallel query or parallel index creation that created temporary files, we could be interrupted by a statement timeout. The error handling path would then fail to clean up the files too, because the callback was already popped off the list. Prevent this hazard by holding interrupts while the cleanup code runs. Thanks to Heikki Linnakangas for this suggestion. Back-patch to all supported releases. Reported-by: Justin Pryzby Discussion: https://postgr.es/m/20191212180506.GR2082@telsasoft.com --- src/backend/storage/ipc/dsm.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/src/backend/storage/ipc/dsm.c b/src/backend/storage/ipc/dsm.c index ae82b4bdc0..23bf192727 100644 --- a/src/backend/storage/ipc/dsm.c +++ b/src/backend/storage/ipc/dsm.c @@ -771,8 +771,10 @@ dsm_detach(dsm_segment *seg) /* * Invoke registered callbacks. Just in case one of those callbacks * throws a further error that brings us back here, pop the callback - * before invoking it, to avoid infinite error recursion. + * before invoking it, to avoid infinite error recursion. Don't allow + * interrupts to prevent cleanup from running to completion. */ + HOLD_INTERRUPTS(); while (!slist_is_empty(&seg->on_detach)) { slist_node *node; @@ -788,6 +790,7 @@ dsm_detach(dsm_segment *seg) function(seg, arg); } + RESUME_INTERRUPTS(); /* * Try to remove the mapping, if one exists. Normally, there will be, but -- 2.20.1