gh-126238: Fix possible null pointer dereference of freevars in _PyCompile_LookupArg (#126239)

federicovalenso · blurb-it[bot] · ZeroIntensity · web-flow · commit 8525c9375f25 · 2024-11-05T20:34:33.000+03:00
* Replace Py_DECREF by Py_XDECREF

Co-authored-by: blurb-it[bot] &lt;43283697+blurb-it[bot]@users.noreply.github.com&gt;
Co-authored-by: Peter Bierma &lt;zintensitydev@gmail.com&gt;
diff --git a/Python/compile.c b/Python/compile.c
@@ -901,7 +901,7 @@ _PyCompile_LookupArg(compiler *c, PyCodeObject *co, PyObject *name)
             c->u->u_metadata.u_name,
             co->co_name,
             freevars);
-        Py_DECREF(freevars);
+        Py_XDECREF(freevars);
         return ERROR;
     }
     return arg;

Original file line number	Diff line number	Diff line change
`@@ -901,7 +901,7 @@ _PyCompile_LookupArg(compiler c, PyCodeObject co, PyObject *name)`
`901`	`901`	`c->u->u_metadata.u_name,`
`902`	`902`	`co->co_name,`
`903`	`903`	`freevars);`
`904`		`- Py_DECREF(freevars);`
	`904`	`+ Py_XDECREF(freevars);`
`905`	`905`	`return ERROR;`
`906`	`906`	`}`
`907`	`907`	`return arg;`