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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2021-07-07 15:21:25 -0400 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2021-07-07 15:21:25 -0400 |
| commit | b9734c13f168ef0d487aa122e486ca9b6dd6aa59 (patch) | |
| tree | 0076995b29ba2dd520431156e29b276d7c56d8fb /contrib/postgres_fdw/postgres_fdw.c | |
| parent | 9d2a7757347cb1adb48599fce4dcde0f1fc9e9ae (diff) | |
| download | postgresql-b9734c13f168ef0d487aa122e486ca9b6dd6aa59.tar.gz postgresql-b9734c13f168ef0d487aa122e486ca9b6dd6aa59.zip | |
Fix crash in postgres_fdw for provably-empty remote UPDATE/DELETE.
In 86dc90056, I'd written find_modifytable_subplan with the assumption
that if the immediate child of a ModifyTable is a Result, it must be
a projecting Result with a subplan. However, if the UPDATE or DELETE
has a provably-constant-false WHERE clause, that's not so: we'll
generate a dummy subplan with a childless Result. Add the missing
null-check so we don't crash on such cases.
Per report from Alexander Pyhalov.
Discussion: https://postgr.es/m/b9a6f53549456b2f3e2fd150dcd79d72@postgrespro.ru
Diffstat (limited to 'contrib/postgres_fdw/postgres_fdw.c')
| -rw-r--r-- | contrib/postgres_fdw/postgres_fdw.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 5cf10402a20..f15c97ad7a4 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -2370,7 +2370,9 @@ find_modifytable_subplan(PlannerInfo *root, if (subplan_index < list_length(appendplan->appendplans)) subplan = (Plan *) list_nth(appendplan->appendplans, subplan_index); } - else if (IsA(subplan, Result) && IsA(outerPlan(subplan), Append)) + else if (IsA(subplan, Result) && + outerPlan(subplan) != NULL && + IsA(outerPlan(subplan), Append)) { Append *appendplan = (Append *) outerPlan(subplan); |