On Mon, Aug 24, 2020 at 12:01:27PM +0100, David Brownlee wrote: > > > I think the general consensus is that ffs can be inconsistent it ways > > > fsck is unable to detect. > > > > ...much less fix. Yes. When I was doing the program that eventually > > got massaged into resize_ffs, during development I had some filesystems > > that were definitely corrupted but that fsck was happy with. (I rather > > wish I'd saved some of them as test cases, but I didn't.)
I also once after abusing rename got a filesystem where fsck -y didn't converge; I had to newfs it. > Sounds like there is an in interesting fuzzing project in there for > someone - make a filesystem mage and the repeatedly damage it, then > see if fsck can fix it, then if you get a rump panic when moving > everything around, and then re-run fsck to see if it indicates any new > issues :) One can do that, but given that there are lots of edge cases and many of them will be hard to reach, formal verification might be more effective. -- David A. Holland dholl...@netbsd.org