Re: [syzbot] [hfs?] WARNING in hfs_write_inode

From: Viacheslav Dubeyko
Date: Thu Jan 05 2023 - 11:45:45 EST




> On Jan 5, 2023, at 7:46 AM, Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
>
> On Wed, Jan 04, 2023 at 08:37:16PM -0800, Viacheslav Dubeyko wrote:
>> Also, as far as I can see, available volume in report (mount_0.gz) somehow corrupted already:
>
> Syzbot generates deliberately-corrupted (aka fuzzed) filesystem images.
> So basically, you can't trust anything you read from the disc.
>

If the volume has been deliberately corrupted, then no guarantee that file system
driver will behave nicely. Technically speaking, inode write operation should never
happened for corrupted volume because the corruption should be detected during
b-tree node initialization time. If we would like to achieve such nice state of HFS/HFS+
drivers, then it requires a lot of refactoring/implementation efforts. I am not sure that
it is worth to do because not so many guys really use HFS/HFS+ as the main file
system under Linux.

Thanks,
Slava.