[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Bug#985689: Needs CONFIG_UNICODE to mount ext4 fs with case-insensitivity feature



* On 3/22/21 9:40 AM, Bastian Blank wrote:
> Control: tags -1 moreinfo
> 
> On Mon, Mar 22, 2021 at 08:40:34AM +0100, Mihai Moldovan wrote:
>> Currently, mounting an EXT4-formatted volume with the case-insensitivity feature
>> is impossible since CONFIG_UNICODE is not enabled in the kernel configuration.
> 
> Why would anyone want to do that?

That point is debatable. I'd like to enable it in case I'd ever need it and it's
pretty safe to do so. Even if the feature is enabled in ext4, it won't actually
be used unless explicitly enabled on a per-directory basis. It won't just make
the whole file system case-insensitive, but can be useful in niche situations
like improved wine compatibility.

In any case, I fear that the better argument (since others seem to lead to a
holy war/gut feeling route) is that e2fsprogs can create such a file system (-O
casefold), so it would be illogical to have a kernel which is not being able to
mount such a volume.


>> My best guess is that the chance of regressions is very low.
> 
> In recent history it's just CVE-2021-21300.

Which was a bug in git, not the kernel side of things, as far as I can see.

The issue is that, currently, you can create such a file system and even if the
feature is not actually used (since no directory within the volume enables
case-insensitivity), the stock Debian kernel won't be able mount it.

File systems like FAT aren't just disabled in the kernel configuration just
because they happen to be case-insensitive by design.



Mihai

Attachment: OpenPGP_signature
Description: OpenPGP digital signature


Reply to: