Buffer overflow in big endian

python · zooba · Feb 12, 2024 · Feb 2, 2024 · Feb 2, 2024 · Feb 2, 2024
commit 7b446485997c3d35db88c1c19bc03714132ee136
diff --git a/Objects/longobject.c b/Objects/longobject.c
@@ -1185,7 +1185,7 @@ PyLong_AsNativeBytes(PyObject* vv, void* buffer, size_t n, int endianness)
             }
             else {
                 memset(buffer, fill, n - sizeof(cv.b));
-                memcpy((char *)buffer + n - sizeof(cv.b), cv.b, n);
+                memcpy((char *)buffer + n - sizeof(cv.b), cv.b, sizeof(cv.b));
             }
 #endif
         }
-Original file line number
+Diff line change
@@ Expand Up @@
                 }
                 else {
                     memset(buffer, fill, n - sizeof(cv.b));
-                    memcpy((char *)buffer + n - sizeof(cv.b), cv.b, n);
+                    memcpy((char *)buffer + n - sizeof(cv.b), cv.b, sizeof(cv.b));
                 }
     #endif
             }
@@ Expand Down @@