If I understand it correctly, it is even worse, because malloc could return not NULL and still throw an exception when you try to write to the 'allocated' memor

If I understand it correctly, it is even worse, because malloc could return not NULL and still throw an exception when you try to write to the 'allocated' memory. See for example https://linuxembedded.fr/2020/01/overcommit-memory-in-linux https://linuxembedded.fr/2020/01/overcommit-memory-in-linux