Re: RFC: from FIBMAP to FIONDEV

Re: RFC: from FIBMAP to FIONDEV

[Jason Lunz]

I'm looking for a way to do FIBMAP on linux 2.4 without being root, and
I learned from the archive that it's restricted for security reasons,
and that it's obsolete anyway.  I found this discussion about a
replacement called FIONDEV:

http://uwsg.iu.edu/hypermail/linux/kernel/9906.1/0817.html

However, I can't find any reference to FIONDEV in current 2.4 sources.
Was anything similar ever coded? Is there a better way then FIBMAP to
get the lba of a file, or are we still stuck with having to have
CAP_SYS_RAWIO in order to do that? This is something that all linux dvd
programs need to do in order to decrypt DVD, and it'd be nice if they
didn't all have to run as root. :)

Jason

Re: RFC: from FIBMAP to FIONDEV

[Alan Cox]

> I'm looking for a way to do FIBMAP on linux 2.4 without being root, and
> I learned from the archive that it's restricted for security reasons,
> and that it's obsolete anyway.  I found this discussion about a
> replacement called FIONDEV:

FIBMAP can be handled per fs by auditing the code paths. First job would be
to push the security check into each fs, then audit the fs's and then change
them. But its really a 2.5 job since any third party fs might spontaneously
become insecure oitherwise