Subject: mknod not working inside guest even with MKNOD bcap
From: Thomas Weber <l_vserver@mail2news.4t2.com>
Date: Tue, 01 Dec 2009 08:24:34 +0100

Hello,

playing around I found that I can't use mknod inside a vserver. If I set
MKNOD in bcapabilities this seems to have no effect.


# vattribute --xid 179 --get
bcapabilities:
CHOWN,DAC_OVERRIDE,DAC_READ_SEARCH,FOWNER,FSETID,KILL,SETGID,SETUID,NET_BIND_SERVICE,SYS_CHROOT,SYS_PTRACE,SYS_BOOT,SYS_TTY_CONFIG,MKNOD,LEASE,AUDIT_WRITE
ccapabilities:
set_utsname,raw_icmp
flags:
fakeinit,virt_uptime,hide_netif,state_init,state_admin,sc_helper

inside the guest I always get:
# mknod TEST b 200 200
mknod: `TEST': Operation not permitted

setting / resetting SYS_NICE via
vattribute --xid 179 --bcap SYS_NICE

just works fine.

I've testet on:
2.6.31.6-vs2.3.0.36.24 #2 SMP Thu Nov 26 19:48:40 CET 2009 x86_64 GNU/Linux
util-vserver 0.30.216~r2842-2x1

2.6.27.8-vs2.3.0.36.2 #1 SMP Wed Dec 10 19:36:03 CET 2008 x86_64 GNU/Linux
util-vserver 0.30.214-4backport1x

2.6.22.19-vs23034 #1 SMP Tue Apr 1 02:01:28 CEST 2008 x86_64 GNU/Linux
util-vserver 0.30.214-4backport1x

2.6.31.6-vs2.3.0.36.23 #1 SMP Tue Nov 10 04:18:26 CET 2009 i686 GNU/Linux
util-vserver 0.30.216~r2772-6

all exposing the same behaviour.
Am I missing something?

  Tom