Jails that keep hanging around
Pawel Jakub Dawidek
pjd at FreeBSD.org
Mon Feb 16 07:50:08 PST 2004
On Mon, Feb 16, 2004 at 06:12:18PM +0300, Maxim Konovalov wrote:
+> > +> What I really do not understand why we do not leak in non-jail
+> > +> environment?
+> >
+> > I'm sure we are, this is just hard to check, because we don't have
+> > list with allocated 'cred' structures.
+> >
+> > But try to do your test without a jail and track 2nd column in:
+> >
+> > # sysctl kern.malloc | grep cred
+> >
+> > Number of objects grows when I'm killing daemon while connection
+> > exists. I'm wondering if this cannot be used to some DoS attack.
+>
+> Can't reproduce:
+>
+> $ vmstat -m | grep cred
+> cred 38 5K 5K 22714 128
+>
+> [ serveral nc & telnet tests I port early in non-jail environment ]
+>
+> $ vmstat -m | grep cred
+> cred 38 5K 5K 22833 128
Probably, because no new cred structure is allocated when you run 'nc'
without a jail (only this one used by your shell is referenced again).
Try to do:
# su - <some_user> -c "/usr/local/bin/nc -p 1234 -l 127.0.0.1"
--
Pawel Jakub Dawidek http://www.FreeBSD.org
pjd at FreeBSD.org http://garage.freebsd.pl
FreeBSD committer Am I Evil? Yes, I Am!
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-current/attachments/20040216/eeb0c7f6/attachment.bin
More information about the freebsd-current
mailing list