Created attachment 330900 [details] [review]
patch to fix heap overflow

I have discovered a heap overflow in gnome-session with the help of address sanitizer.

This is the code (main.c, function require_dbus_session):
        new_argv = g_malloc (argc + 3 * sizeof (*argv));

The intention is to allocate space for (argc + 3) pointers. However obviously a bracket is missing, therefore only argc bytes + 3 * pointer size gets allocated, which will be to small. Later on this leads to invalid memory writes.

The fix is trivial: Bracket around argc + 3. See attached patch. Affects current git code.