Re: 2.6.25 Kernel - Problems with capabilities

[Andrew Morgan <morgan@kernel.org>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

serge@hallyn.com wrote:
| Quoting David (david@unsolicited.net):
|> Casey Schaufler wrote:
|>> Do you have a libcap that reflects the change from 32 capabilities
|>> to 64? You'll be looking for libcap.so.2.06 or thereabouts.
|>>
|> Adding libcap-2.08 and recompiling ntpd has fixed the issue, and I'm now
|> running normally, thanks!
|
| I don't understand why, though.  Looking at the ntpd code (ntp-4.2.4p4)
| it just does a cap_set_proc(cap_from_text("X=epi"));  It should simply
| be sending in the _LINUX_CAPABILITY_VERSION which shipped with libcap,
| which should have been _V1, and the kernel should honor that so long as
| you didn't try to send in caps > 31, which ntpd wasn't.
|
|> Was this userspace visible change planned in advance for 2.6.25 ? ...
as I
|> guess a few other people with venerable old userspace components may
come
|> across this issue.
|>
|> Cheers
|> David
|
| It's been in the works a long time and we thought we'd done pretty
| well with backward compatibility.  I really don't see why you had
| that failure!

I'm confused (and somewhat concerned) about this too. 32-bit capability
apps should act fine. The only thing you might notice is a strange
comment about it in /var/log/messages.

David, can you run strace on the failing program (configuration)?

[I'll see if I can read the complete thread on one of the archives and
see if anything else sticks out.]

Thanks

Andrew

|
| Do you know which version of libcap you had before?
|
| thanks,
| -serge
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFIC+NP+bHCR3gb8jsRAjunAKDXe/fDfwIJWi6wgtpdxZefbRq5SACffb1+
pQNi1C/8PPGWYpUXFxizUuI=
=LHl0
-----END PGP SIGNATURE-----