Re: The very definition of technical debt
From what I understand here is what happened.
Linus first noticed a bug that was a side effect of this underlying error and attempted to fix it. He rolled it back due to the S/390 build failing and just said screw it since the bug he was experiencing wasn't actually doing anything bad at the time. This was all before Copy On Write was implemented into the kernel so there wasn't any vulnerability yet. Fast forward 10 years and COW is now implemented in the kernel around this buggy code. Someone found the bug and used it in combination with COW to produce this exploit in the wild. Then it was noticed and patched. I don't think Linus would have just left a bug like that sit for 10 years unless it was pretty trivial and at the time couldn't cause anything malicious.
Biting the hand that feeds IT
