kern/122047: [ext2fs] incorrect handling of UF_IMMUTABLE / UF_APPEND, flag on EXT2FS (maybe others)

[Bruce Evans]

On Mon, 2 Jun 2008, Julian Elischer wrote:

> Ighighi wrote:
>> On Linux, only the root user may set/clear the immutable/append flags
>> on ext2 filesystems... Shouldn't FreeBSD do this too, as a POLA?
>
> No I think it should preserver the BSD scheme where being able to
> change the immutable bits is controlled by the system secure level.
> (and your UID of course). At least I think that is what I would
> expect. (All file systems to behave about the same for a
> particular OS.

No, the securelevel already controls things, and the BSD scheme reduces
to only allowing root (strictly, processes with appropriate privilege,
as restricted by securelevel and jails etc, but never mere users), to
change immutable bits, because ext2fs doesn't have any user immutable
bits to change (except phantom bits due to bugs in the current FreeBSD
implementation).

Bruce