Hello! In continuation of the topic I would like to suggest solution. This patch adds several checks to the vulnerable functions above.
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index d85e313908..102d0e1574 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -3043,6 +3043,9 @@ CommitTransactionCommand(void)
 	TransactionState s = CurrentTransactionState;
 	SavedTransactionCharacteristics savetc;
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	SaveTransactionCharacteristics(&savetc);
 
 	switch (s->blockState)
@@ -5500,6 +5503,9 @@ ShowTransactionStateRec(const char *str, TransactionState s)
 {
 	StringInfoData buf;
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	initStringInfo(&buf);
 
 	if (s->nChildXids > 0)
diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index 7acf654bf8..58a1d70b8a 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -76,6 +76,7 @@
 #include "commands/trigger.h"
 #include "commands/typecmds.h"
 #include "funcapi.h"
+#include "miscadmin.h"
 #include "nodes/nodeFuncs.h"
 #include "parser/parsetree.h"
 #include "rewrite/rewriteRemove.h"
@@ -524,6 +525,11 @@ findDependentObjects(const ObjectAddress *object,
 	if (stack_address_present_add_flags(object, objflags, stack))
 		return;
 
+	/* since this function recurses, it could be driven to stack overflow,
+	 * because of the deep dependency tree, not only due to dependency loops.
+	 */
+	check_stack_depth();
+
 	/*
 	 * It's also possible that the target object has already been completely
 	 * processed and put into targetObjects.  If so, again we just add the
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index 4f006820b8..a88550913d 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -552,6 +552,9 @@ CheckAttributeType(const char *attname,
 	char		att_typtype = get_typtype(atttypid);
 	Oid			att_typelem;
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	if (att_typtype == TYPTYPE_PSEUDO)
 	{
 		/*
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 7c697a285b..f22da79c65 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -6684,6 +6684,9 @@ ATExecAddColumn(List **wqueue, AlteredTableInfo *tab, Relation rel,
 	TupleDesc	tupdesc;
 	FormData_pg_attribute *aattr[] = {&attribute};
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	/* At top level, permission check was done in ATPrepCmd, else do it */
 	if (recursing)
 		ATSimplePermissions((*cmd)->subtype, rel, ATT_TABLE | ATT_FOREIGN_TABLE);
@@ -8383,6 +8386,10 @@ ATExecDropColumn(List **wqueue, Relation rel, const char *colName,
 
 	/* Initialize addrs on the first invocation */
 	Assert(!recursing || addrs != NULL);
+
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	if (!recursing)
 		addrs = new_object_addresses();
 
@@ -10839,6 +10846,9 @@ ATExecAlterConstrRecurse(Constraint *cmdcon, Relation conrel, Relation tgrel,
 	Oid			refrelid;
 	bool		changed = false;
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	currcon = (Form_pg_constraint) GETSTRUCT(contuple);
 	conoid = currcon->oid;
 	refrelid = currcon->confrelid;
@@ -11839,6 +11849,9 @@ ATExecDropConstraint(Relation rel, const char *constrName,
 	bool		is_no_inherit_constraint = false;
 	char		contype;
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	/* At top level, permission check was done in ATPrepCmd, else do it */
 	if (recursing)
 		ATSimplePermissions(AT_DropConstraint, rel, ATT_TABLE | ATT_FOREIGN_TABLE);
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index aa584848cf..77a5eb526c 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -2318,6 +2318,10 @@ static Node *
 eval_const_expressions_mutator(Node *node,
 							   eval_const_expressions_context *context)
 {
+
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	if (node == NULL)
 		return NULL;
 	switch (nodeTag(node))
diff --git a/src/backend/utils/adt/jsonpath_exec.c b/src/backend/utils/adt/jsonpath_exec.c
index b561f0e7e8..dc7ab387ea 100644
--- a/src/backend/utils/adt/jsonpath_exec.c
+++ b/src/backend/utils/adt/jsonpath_exec.c
@@ -1232,6 +1232,9 @@ executeBoolItem(JsonPathExecContext *cxt, JsonPathItem *jsp,
 	JsonPathBool res;
 	JsonPathBool res2;
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	if (!canHaveNext && jspHasNext(jsp))
 		elog(ERROR, "boolean jsonpath item cannot have next item");
 
diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c
index 0b00802df7..cc06c00a49 100644
--- a/src/backend/utils/mmgr/mcxt.c
+++ b/src/backend/utils/mmgr/mcxt.c
@@ -392,6 +392,9 @@ MemoryContextDelete(MemoryContext context)
 	/* And not CurrentMemoryContext, either */
 	Assert(context != CurrentMemoryContext);
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	/* save a function call in common case where there are no children */
 	if (context->firstchild != NULL)
 		MemoryContextDeleteChildren(context);
@@ -750,6 +753,9 @@ MemoryContextStatsInternal(MemoryContext context, int level,
 
 	Assert(MemoryContextIsValid(context));
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	/* Examine the context itself */
 	context->methods->stats(context,
 							print ? MemoryContextStatsPrint : NULL,
@@ -915,6 +921,9 @@ MemoryContextCheck(MemoryContext context)
 
 	Assert(MemoryContextIsValid(context));
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	context->methods->check(context);
 	for (child = context->firstchild; child != NULL; child = child->nextchild)
 		MemoryContextCheck(child);

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