postgres.git / summary / log / commit / refs

commit    c0f53139611cf6b24175bea27bfbddb0ea5b7378
Author:   Tom Lane <tgl@sss.pgh.pa.us>
Date:     Thu Jul 20 18:23:46 2023 +0000

    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);


[parent: 7825a1b01e40]