From 95036ea25d47f0081bda2ba96ea327f3375cb6a4 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Thu, 22 Nov 2018 17:15:37 +0100 Subject: [3.7] bpo-9263: _PyObject_Dump() detects freed memory (GH-10061) (GH-10662) * bpo-9263: _PyObject_Dump() detects freed memory (GH-10061) _PyObject_Dump() now uses an heuristic to check if the object memory has been freed: log "" in that case. The heuristic rely on the debug hooks on Python memory allocators which fills the memory with DEADBYTE (0xDB) when memory is deallocated. Use PYTHONMALLOC=debug to always enable these debug hooks. (cherry picked from commit 82af0b63b07aa8d92b50098e382b458143cfc677) * bpo-9263: Fix _PyObject_Dump() for freed object (#10661) If _PyObject_Dump() detects that the object is freed, don't try to dump it (exit immediately). Enhance also _PyObject_IsFreed(): it now detects if the pointer itself looks like freed memory. (cherry picked from commit 2cf5d32fd9e61488e8b0be55a2e92a752ba8b06b) --- Include/object.h | 1 + Include/pymem.h | 4 +++- 2 files changed, 4 insertions(+), 1 deletion(-) (limited to 'Include') diff --git a/Include/object.h b/Include/object.h index c772deaf57..bcf78afe6b 100644 --- a/Include/object.h +++ b/Include/object.h @@ -521,6 +521,7 @@ struct _Py_Identifier; PyAPI_FUNC(int) PyObject_Print(PyObject *, FILE *, int); PyAPI_FUNC(void) _Py_BreakPoint(void); PyAPI_FUNC(void) _PyObject_Dump(PyObject *); +PyAPI_FUNC(int) _PyObject_IsFreed(PyObject *); #endif PyAPI_FUNC(PyObject *) PyObject_Repr(PyObject *); PyAPI_FUNC(PyObject *) PyObject_Str(PyObject *); diff --git a/Include/pymem.h b/Include/pymem.h index 8ee0efddca..ef6e0bb5e2 100644 --- a/Include/pymem.h +++ b/Include/pymem.h @@ -55,7 +55,9 @@ PyAPI_FUNC(int) PyTraceMalloc_Untrack( PyAPI_FUNC(PyObject*) _PyTraceMalloc_GetTraceback( unsigned int domain, uintptr_t ptr); -#endif /* !Py_LIMITED_API */ + +PyAPI_FUNC(int) _PyMem_IsFreed(void *ptr, size_t size); +#endif /* !defined(Py_LIMITED_API) */ /* BEWARE: -- cgit v1.2.1