Issue #18203: Replace malloc() with PyMem_RawMalloc() at Python initialization

* Replace malloc() with PyMem_RawMalloc()
* Replace PyMem_Malloc() with PyMem_RawMalloc() where the GIL is not held.
* _Py_char2wchar() now returns a buffer allocated by PyMem_RawMalloc(), instead
  of PyMem_Malloc()

Python/fileutils.c

@@ -229,7 +229,7 @@ decode_ascii_surrogateescape(const char *arg, size_t *size)
    Use _Py_wchar2char() to encode the character string back to a byte string.
 
    Return a pointer to a newly allocated wide character string (use
-   PyMem_Free() to free the memory) and write the number of written wide
+   PyMem_RawFree() to free the memory) and write the number of written wide
    characters excluding the null character into *size if size is not NULL, or
    NULL on error (decoding or memory allocation error). If size is not NULL,
    *size is set to (size_t)-1 on memory error and (size_t)-2 on decoding
@@ -283,7 +283,7 @@ _Py_char2wchar(const char* arg, size_t *size)
     argsize = mbstowcs(NULL, arg, 0);
 #endif
     if (argsize != (size_t)-1) {
-        res = (wchar_t *)PyMem_Malloc((argsize+1)*sizeof(wchar_t));
+        res = (wchar_t *)PyMem_RawMalloc((argsize+1)*sizeof(wchar_t));
         if (!res)
             goto oom;
         count = mbstowcs(res, arg, argsize+1);
@@ -300,7 +300,7 @@ _Py_char2wchar(const char* arg, size_t *size)
                 return res;
             }
         }
-        PyMem_Free(res);
+        PyMem_RawFree(res);
     }
     /* Conversion failed. Fall back to escaping with surrogateescape. */
 #ifdef HAVE_MBRTOWC
@@ -309,7 +309,7 @@ _Py_char2wchar(const char* arg, size_t *size)
     /* Overallocate; as multi-byte characters are in the argument, the
        actual output could use less memory. */
     argsize = strlen(arg) + 1;
-    res = (wchar_t*)PyMem_Malloc(argsize*sizeof(wchar_t));
+    res = (wchar_t*)PyMem_RawMalloc(argsize*sizeof(wchar_t));
     if (!res)
         goto oom;
     in = (unsigned char*)arg;
@@ -325,7 +325,7 @@ _Py_char2wchar(const char* arg, size_t *size)
                since we provide everything that we have -
                unless there is a bug in the C library, or I
                misunderstood how mbrtowc works. */
-            PyMem_Free(res);
+            PyMem_RawFree(res);
             if (size != NULL)
                 *size = (size_t)-2;
             return NULL;
@@ -648,12 +648,12 @@ _Py_wreadlink(const wchar_t *path, wchar_t *buf, size_t bufsiz)
         return -1;
     }
     if (bufsiz <= r1) {
-        PyMem_Free(wbuf);
+        PyMem_RawFree(wbuf);
         errno = EINVAL;
         return -1;
     }
     wcsncpy(buf, wbuf, bufsiz);
-    PyMem_Free(wbuf);
+    PyMem_RawFree(wbuf);
     return (int)r1;
 }
 #endif
@@ -689,12 +689,12 @@ _Py_wrealpath(const wchar_t *path,
         return NULL;
     }
     if (resolved_path_size <= r) {
-        PyMem_Free(wresolved_path);
+        PyMem_RawFree(wresolved_path);
         errno = EINVAL;
         return NULL;
     }
     wcsncpy(resolved_path, wresolved_path, resolved_path_size);
-    PyMem_Free(wresolved_path);
+    PyMem_RawFree(wresolved_path);
     return resolved_path;
 }
 #endif
@@ -720,11 +720,11 @@ _Py_wgetcwd(wchar_t *buf, size_t size)
     if (wname == NULL)
         return NULL;
     if (size <= len) {
-        PyMem_Free(wname);
+        PyMem_RawFree(wname);
         return NULL;
     }
     wcsncpy(buf, wname, size);
-    PyMem_Free(wname);
+    PyMem_RawFree(wname);
     return buf;
 #endif
 }

Python/pystate.c

@@ -6,11 +6,11 @@
 /* --------------------------------------------------------------------------
 CAUTION
 
-Always use malloc() and free() directly in this file.  A number of these
-functions are advertised as safe to call when the GIL isn't held, and in
-a debug build Python redirects (e.g.) PyMem_NEW (etc) to Python's debugging
-obmalloc functions.  Those aren't thread-safe (they rely on the GIL to avoid
-the expense of doing their own locking).
+Always use PyMem_RawMalloc() and PyMem_RawFree() directly in this file.  A
+number of these functions are advertised as safe to call when the GIL isn't
+held, and in a debug build Python redirects (e.g.) PyMem_NEW (etc) to Python's
+debugging obmalloc functions.  Those aren't thread-safe (they rely on the GIL
+to avoid the expense of doing their own locking).
 -------------------------------------------------------------------------- */
 
 #ifdef HAVE_DLOPEN
@@ -60,7 +60,7 @@ PyInterpreterState *
 PyInterpreterState_New(void)
 {
     PyInterpreterState *interp = (PyInterpreterState *)
-                                 malloc(sizeof(PyInterpreterState));
+                                 PyMem_RawMalloc(sizeof(PyInterpreterState));
 
     if (interp != NULL) {
         HEAD_INIT();
@@ -148,7 +148,7 @@ PyInterpreterState_Delete(PyInterpreterState *interp)
         Py_FatalError("PyInterpreterState_Delete: remaining threads");
     *p = interp->next;
     HEAD_UNLOCK();
-    free(interp);
+    PyMem_RawFree(interp);
 #ifdef WITH_THREAD
     if (interp_head == NULL && head_mutex != NULL) {
         PyThread_free_lock(head_mutex);
@@ -168,7 +168,7 @@ threadstate_getframe(PyThreadState *self)
 static PyThreadState *
 new_threadstate(PyInterpreterState *interp, int init)
 {
-    PyThreadState *tstate = (PyThreadState *)malloc(sizeof(PyThreadState));
+    PyThreadState *tstate = (PyThreadState *)PyMem_RawMalloc(sizeof(PyThreadState));
 
     if (_PyThreadState_GetFrame == NULL)
         _PyThreadState_GetFrame = threadstate_getframe;
@@ -365,7 +365,7 @@ tstate_delete_common(PyThreadState *tstate)
     if (tstate->next)
         tstate->next->prev = tstate->prev;
     HEAD_UNLOCK();
-    free(tstate);
+    PyMem_RawFree(tstate);
 }
 
 
@@ -432,7 +432,7 @@ _PyThreadState_DeleteExcept(PyThreadState *tstate)
     for (p = garbage; p; p = next) {
         next = p->next;
         PyThreadState_Clear(p);
-        free(p);
+        PyMem_RawFree(p);
     }
 }
 

Python/thread.c

@@ -231,7 +231,7 @@ find_key(int key, void *value)
         assert(p == NULL);
         goto Done;
     }
-    p = (struct key *)malloc(sizeof(struct key));
+    p = (struct key *)PyMem_RawMalloc(sizeof(struct key));
     if (p != NULL) {
         p->id = id;
         p->key = key;
@@ -270,7 +270,7 @@ PyThread_delete_key(int key)
     while ((p = *q) != NULL) {
         if (p->key == key) {
             *q = p->next;
-            free((void *)p);
+            PyMem_RawFree((void *)p);
             /* NB This does *not* free p->value! */
         }
         else
@@ -324,7 +324,7 @@ PyThread_delete_key_value(int key)
     while ((p = *q) != NULL) {
         if (p->key == key && p->id == id) {
             *q = p->next;
-            free((void *)p);
+            PyMem_RawFree((void *)p);
             /* NB This does *not* free p->value! */
             break;
         }
@@ -357,7 +357,7 @@ PyThread_ReInitTLS(void)
     while ((p = *q) != NULL) {
         if (p->id != id) {
             *q = p->next;
-            free((void *)p);
+            PyMem_RawFree((void *)p);
             /* NB This does *not* free p->value! */
         }
         else