fix leak in _PyCode_Update

iritkatriel · gvanrossum · commit 715e2b86e2d8 · 2021-07-24T12:04:39.000+02:00
diff --git a/Objects/codeobject.c b/Objects/codeobject.c
@@ -296,7 +296,7 @@ _PyCode_Validate(struct _PyCodeConstructor *con)
 }
 
 static void
-init_code(PyCodeObject *co, struct _PyCodeConstructor *con)
+init_code(PyCodeObject *co, struct _PyCodeConstructor *con, bool is_new)
 {
     if (con->localsplusnames) {
         int nlocalsplus = (int)PyTuple_GET_SIZE(con->localsplusnames);
@@ -318,6 +318,11 @@ init_code(PyCodeObject *co, struct _PyCodeConstructor *con)
         co->co_nfreevars = 0;
     }
 
+    if(!is_new) {
+        Py_XDECREF(co->co_filename);
+        Py_XDECREF(co->co_name);
+        Py_XDECREF(co->co_qualname);
+    }
     Py_INCREF(con->filename);
     co->co_filename = con->filename;
     Py_INCREF(con->name);
@@ -420,7 +425,8 @@ _PyCode_New(struct _PyCodeConstructor *con)
         PyErr_NoMemory();
         return NULL;
     }
-    init_code(co, con);
+
+    init_code(co, con, true);
 
     return co;
 }
@@ -442,7 +448,7 @@ _PyCode_Update(struct _PyCodeConstructor *con, PyCodeObject *code)
         con->columntable = Py_None;
     }
 
-    init_code(code, con);  // TODO: This leaks!
+    init_code(code, con, false);
 
     return code;
 }

Original file line number	Diff line number	Diff line change
`@@ -296,7 +296,7 @@ _PyCode_Validate(struct _PyCodeConstructor *con)`
`296`	`296`	`}`
`297`	`297`
`298`	`298`	`static void`
`299`		`-init_code(PyCodeObject co, struct _PyCodeConstructor con)`
	`299`	`+init_code(PyCodeObject co, struct _PyCodeConstructor con, bool is_new)`
`300`	`300`	`{`
`301`	`301`	`if (con->localsplusnames) {`
`302`	`302`	`int nlocalsplus = (int)PyTuple_GET_SIZE(con->localsplusnames);`
`@@ -318,6 +318,11 @@ init_code(PyCodeObject co, struct _PyCodeConstructor con)`
`318`	`318`	`co->co_nfreevars = 0;`
`319`	`319`	`}`
`320`	`320`
	`321`	`+ if(!is_new) {`
	`322`	`+ Py_XDECREF(co->co_filename);`
	`323`	`+ Py_XDECREF(co->co_name);`
	`324`	`+ Py_XDECREF(co->co_qualname);`
	`325`	`+ }`
`321`	`326`	`Py_INCREF(con->filename);`
`322`	`327`	`co->co_filename = con->filename;`
`323`	`328`	`Py_INCREF(con->name);`
`@@ -420,7 +425,8 @@ _PyCode_New(struct _PyCodeConstructor *con)`
`420`	`425`	`PyErr_NoMemory();`
`421`	`426`	`return NULL;`
`422`	`427`	`}`
`423`		`- init_code(co, con);`
	`428`	`+`
	`429`	`+ init_code(co, con, true);`
`424`	`430`
`425`	`431`	`return co;`
`426`	`432`	`}`
`@@ -442,7 +448,7 @@ _PyCode_Update(struct _PyCodeConstructor con, PyCodeObject code)`
`442`	`448`	`con->columntable = Py_None;`
`443`	`449`	`}`
`444`	`450`
`445`		`- init_code(code, con); // TODO: This leaks!`
	`451`	`+ init_code(code, con, false);`
`446`	`452`
`447`	`453`	`return code;`
`448`	`454`	`}`