bpo-34523, bpo-35322: Fix unicode_encode_locale() (GH-10759) (GH-10761)

vstinner · web-flow · commit 85ab974f78c0 · 2018-11-28T12:42:40.000+01:00
Fix memory leak in PyUnicode_EncodeLocale() and PyUnicode_EncodeFSDefault() on error handling. Fix unicode_encode_locale() error handling. (cherry picked from commit bde9d6b)
diff --git a/Misc/NEWS.d/next/C API/2018-11-28-03-20-36.bpo-35322.Qcqsag.rst b/Misc/NEWS.d/next/C API/2018-11-28-03-20-36.bpo-35322.Qcqsag.rst
@@ -0,0 +1,2 @@
+Fix memory leak in :c:func:`PyUnicode_EncodeLocale` and
+:c:func:`PyUnicode_EncodeFSDefault` on error handling.
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
@@ -3391,10 +3391,9 @@ unicode_encode_locale(PyObject *unicode, const char *errors,
         return NULL;
     }
 
-    Py_ssize_t wlen2 = wcslen(wstr);
-    if (wlen2 != wlen) {
-        PyMem_Free(wstr);
+    if ((size_t)wlen != wcslen(wstr)) {
         PyErr_SetString(PyExc_ValueError, "embedded null character");
+        PyMem_Free(wstr);
         return NULL;
     }
 
@@ -3403,6 +3402,8 @@ unicode_encode_locale(PyObject *unicode, const char *errors,
     const char *reason;
     int res = _Py_EncodeLocaleEx(wstr, &str, &error_pos, &reason,
                                  current_locale, surrogateescape);
+    PyMem_Free(wstr);
+
     if (res != 0) {
         if (res == -2) {
             PyObject *exc;
@@ -3415,15 +3416,12 @@ unicode_encode_locale(PyObject *unicode, const char *errors,
                 PyCodec_StrictErrors(exc);
                 Py_DECREF(exc);
             }
-            return NULL;
         }
         else {
             PyErr_NoMemory();
-            PyMem_Free(wstr);
-            return NULL;
         }
+        return NULL;
     }
-    PyMem_Free(wstr);
 
     PyObject *bytes = PyBytes_FromString(str);
     PyMem_RawFree(str);

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	+Fix memory leak in :c:func:`PyUnicode_EncodeLocale` and
	`2`	+:c:func:`PyUnicode_EncodeFSDefault` on error handling.
Original file line number	Diff line number	Diff line change
`@@ -3391,10 +3391,9 @@ unicode_encode_locale(PyObject unicode, const char errors,`
`3391`	`3391`	`return NULL;`
`3392`	`3392`	`}`
`3393`	`3393`
`3394`		`- Py_ssize_t wlen2 = wcslen(wstr);`
`3395`		`- if (wlen2 != wlen) {`
`3396`		`- PyMem_Free(wstr);`
	`3394`	`+ if ((size_t)wlen != wcslen(wstr)) {`
`3397`	`3395`	`PyErr_SetString(PyExc_ValueError, "embedded null character");`
	`3396`	`+ PyMem_Free(wstr);`
`3398`	`3397`	`return NULL;`
`3399`	`3398`	`}`
`3400`	`3399`
`@@ -3403,6 +3402,8 @@ unicode_encode_locale(PyObject unicode, const char errors,`
`3403`	`3402`	`const char *reason;`
`3404`	`3403`	`int res = _Py_EncodeLocaleEx(wstr, &str, &error_pos, &reason,`
`3405`	`3404`	`current_locale, surrogateescape);`
	`3405`	`+ PyMem_Free(wstr);`
	`3406`	`+`
`3406`	`3407`	`if (res != 0) {`
`3407`	`3408`	`if (res == -2) {`
`3408`	`3409`	`PyObject *exc;`
`@@ -3415,15 +3416,12 @@ unicode_encode_locale(PyObject unicode, const char errors,`
`3415`	`3416`	`PyCodec_StrictErrors(exc);`
`3416`	`3417`	`Py_DECREF(exc);`
`3417`	`3418`	`}`
`3418`		`- return NULL;`
`3419`	`3419`	`}`
`3420`	`3420`	`else {`
`3421`	`3421`	`PyErr_NoMemory();`
`3422`		`- PyMem_Free(wstr);`
`3423`		`- return NULL;`
`3424`	`3422`	`}`
	`3423`	`+ return NULL;`
`3425`	`3424`	`}`
`3426`		`- PyMem_Free(wstr);`
`3427`	`3425`
`3428`	`3426`	`PyObject *bytes = PyBytes_FromString(str);`
`3429`	`3427`	`PyMem_RawFree(str);`