Check for stack overrun in standard_ProcessUtility().

ProcessUtility can recurse, and indeed can be driven to infinite
recursion, so it ought to have a check_stack_depth() call.  This
covers the reported bug (portal trying to execute itself) and a bunch
of other cases that could perhaps arise somewhere.

Per bug #15428 from Malthe Borch.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/15428-b3c2915ec470b033@postgresql.org

diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 4640225dd487efd4ba596c297b7ac6fa5d53930e..ca36572cd36d4c7488e320d64a7884f0e92f4593 100644 (file)
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -332,6 +332,9 @@ standard_ProcessUtility(Node *parsetree,
 {
        bool            isTopLevel = (context == PROCESS_UTILITY_TOPLEVEL);
 
+       /* This can recurse, so check for excessive recursion */
+       check_stack_depth();
+
        check_xact_readonly(parsetree);
 
        if (completionTag)