From c0f53139611cf6b24175bea27bfbddb0ea5b7378 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 20 Jul 2023 14:23:46 -0400 Subject: [PATCH] Guard against null plan pointer in CachedPlanIsSimplyValid(). If both the passed-in plan pointer and plansource->gplan are NULL, CachedPlanIsSimplyValid would think that the plan pointer is possibly-valid and try to dereference it. For the one extant call site in plpgsql, this situation doesn't normally happen which is why we've not noticed. However, it appears to be possible if the previous use of the cached plan failed, as per report from Justin Pryzby. Add an extra check to prevent crashing. Back-patch to v13 where this code was added. Discussion: https://postgr.es/m/ZLlV+STFz1l/WhAQ@telsasoft.com --- src/backend/utils/cache/plancache.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/backend/utils/cache/plancache.c b/src/backend/utils/cache/plancache.c index 3d3f7a9beae..56c84e1e629 100644 --- a/src/backend/utils/cache/plancache.c +++ b/src/backend/utils/cache/plancache.c @@ -1440,7 +1440,9 @@ CachedPlanIsSimplyValid(CachedPlanSource *plansource, CachedPlan *plan, * that here we *do* check plansource->is_valid, so as to force plan * rebuild if that's become false. */ - if (!plansource->is_valid || plan != plansource->gplan || !plan->is_valid) + if (!plansource->is_valid || + plan == NULL || plan != plansource->gplan || + !plan->is_valid) return false; Assert(plan->magic == CACHEDPLAN_MAGIC);