bin/51619

[Lukas Ertl]

On Thu, 8 May 2003, Kirk McKusick wrote:

> Your proposed patch would work much better. There is a small
> possibility that it would stomp a boot block that just happened
> to have the filesystem magic number at that location, but the
> chances of that seem pretty remote. It does not address the
> alternate superblock issue. The first UFS1 alternate is 32
> sectors (16K) in from the beginning of the disk. That alternate
> also remains untouched by UFS2. So, someone manually running
> fsck will be given the opportunity to look for alternate
> superblocks and will find that one and *still* end up messing
> up the filesystem.

Well, Unix always gives you enough rope to hang yourself :-)

> Indeed to be completely safe, you would need to look up every alternate
> superblock and zero out its magic number (see the last for-loop in
> mkfs() for details on how this is done).

Ok Kirk, thanks for your patience so far. I'm trying to come up with an
extended patch tomorrow.

best regards,
le

-- 
Lukas Ertl                             eMail: l.ertl at univie.ac.at
UNIX-Systemadministrator               Tel.:  (+43 1) 4277-14073
Zentraler Informatikdienst (ZID)       Fax.:  (+43 1) 4277-9140
der Universität Wien                   http://mailbox.univie.ac.at/~le/