bpo-45375: Fix off by one error in buffer allocation (GH-28764)

zooba · web-flow · commit 6c942a86a4fb · 2021-10-06T20:09:33.000+01:00
diff --git a/PC/getpathp.c b/PC/getpathp.c
@@ -266,7 +266,7 @@ canonicalize(wchar_t *buffer, const wchar_t *path)
     }
 
     if (PathIsRelativeW(path)) {
-        wchar_t buff[MAXPATHLEN];
+        wchar_t buff[MAXPATHLEN + 1];
         if (!GetCurrentDirectoryW(MAXPATHLEN, buff)) {
             return _PyStatus_ERR("unable to find current working directory");
         }

Original file line number	Diff line number	Diff line change
`@@ -266,7 +266,7 @@ canonicalize(wchar_t buffer, const wchar_t path)`
`266`	`266`	`}`
`267`	`267`
`268`	`268`	`if (PathIsRelativeW(path)) {`
`269`		`- wchar_t buff[MAXPATHLEN];`
	`269`	`+ wchar_t buff[MAXPATHLEN + 1];`
`270`	`270`	`if (!GetCurrentDirectoryW(MAXPATHLEN, buff)) {`
`271`	`271`	`return _PyStatus_ERR("unable to find current working directory");`
`272`	`272`	`}`