I find a potential bug caused by a improper call to pfree in PostgresSQL 14.1, which is in backend/utils/adt/jsonb_gin.c
Specifically, at line 1116, the pointer 'stack' is assigned with the address of a local variable 'tail'. At line 1163, pfree() is called to free 'stack'. However, pfree is designed to free the memory in heap rather than stack.