Potential memory leak in Parser/parser.c

[RuiliF]

Bug report

In Parse/parse.c, function _loop0_1_rule (line 23809), object _children

  if (_n == _children_capacity) {
      _children_capacity *= 2;
      void **_new_children = PyMem_Realloc(_children, _children_capacity*sizeof(void *));
      if (!_new_children) {
          p->error_indicator = 1;
          PyErr_NoMemory();
          p->level--;
          return NULL; 
      }     
      _children = _new_children;
  }     

If PyMem_Realloc fails, the original object will be kept untouched. Thus returning NULL without free'ing _children will cause a memory leak.

Your environment

Python 3.12

Linked PRs

• gh-101046: fix a potential memory leak in parser.c #101049
• gh-101046: Fix a potential memory leak in the parser when raising MemoryError #101051
• [3.11] gh-101046: Fix a potential memory leak in the parser when raising MemoryError (GH-101051) #101085
• [3.10] gh-101046: Fix a potential memory leak in the parser when raising MemoryError (GH-101051). #101086

[pablogsal]

Thanks for opening the issue @RuiliF, unfortunate #101049 just changes a single rule while all rules are subjected to this. I have created a PR fixing this correctly in #101051.