gh-151126: Fix missing memory error in os._path_splitroot (GH-151339)

sobolevn · miss-islington · commit ed1add46b16c · 2026-06-11T16:25:08.000Z
(cherry picked from commit 10595b1) Co-authored-by: sobolevn <mail@sobolevn.me>
diff --git a/Misc/NEWS.d/next/Library/2026-06-11-16-25-38.gh-issue-151126.bh_Usy.rst b/Misc/NEWS.d/next/Library/2026-06-11-16-25-38.gh-issue-151126.bh_Usy.rst
@@ -0,0 +1,2 @@
+Fix a crash when :exc:`MemoryError` in :func:`!os._path_splitroot`
+was not set properly.
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
@@ -5133,7 +5133,7 @@ os__path_splitroot_impl(PyObject *module, path_t *path)
 
     buffer = (wchar_t*)PyMem_Malloc(sizeof(wchar_t) * (wcslen(path->wide) + 1));
     if (!buffer) {
-        return NULL;
+        return PyErr_NoMemory();
     }
     wcscpy(buffer, path->wide);
     for (wchar_t *p = wcschr(buffer, L'/'); p; p = wcschr(p, L'/')) {

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	+Fix a crash when :exc:`MemoryError` in :func:`!os._path_splitroot`
	`2`	`+was not set properly.`
Original file line number	Diff line number	Diff line change
`@@ -5133,7 +5133,7 @@ os__path_splitroot_impl(PyObject module, path_t path)`
`5133`	`5133`
`5134`	`5134`	`buffer = (wchar_t)PyMem_Malloc(sizeof(wchar_t) (wcslen(path->wide) + 1));`
`5135`	`5135`	`if (!buffer) {`
`5136`		`- return NULL;`
	`5136`	`+ return PyErr_NoMemory();`
`5137`	`5137`	`}`
`5138`	`5138`	`wcscpy(buffer, path->wide);`
`5139`	`5139`	`for (wchar_t *p = wcschr(buffer, L'/'); p; p = wcschr(p, L'/')) {`