[ac29]

I think its fair to call it 0%. Auditing a large, modern code base is going to be impossible for a single person. For example, the Linux kernel is 27.8M lines of code (as of Jan 2020, [0]). Yes, a lot of that code is for drivers you wont use, or platforms you aren't running on. But still, no one person is going to be able to get through all of it with enough attention to detail to notice things like subtle race conditions, especially if they were inserted maliciously.

[0] https://www.phoronix.com/scan.php?page=news_item&px=Linux-Gi...