[lxc-devel] [PATCH] Support MS_SHARED /

[Alexander Vladimirov]

2013/1/8 Serge Hallyn <serge.hallyn at canonical.com>:
> Quoting Alexander Vladimirov (alexander.idkfa.vladimirov at gmail.com):
>> Just like on the host:
>> [idkfa at s10 ~]$ ls -la /dev/{null,tty,urandom,zero,full}
>> crw-rw-rw- 1 root root 1, 7 янв  6 13:30 /dev/full
>> crw-rw-rw- 1 root root 1, 3 янв  6 13:30 /dev/null
>> crw-rw-rw- 1 root tty  5, 0 янв  8 00:03 /dev/tty
>> crw-rw-rw- 1 root root 1, 9 янв  6 13:30 /dev/urandom
>> crw-rw-rw- 1 root root 1, 5 янв  6 13:30 /dev/zero
>>
>> For example
>
> You say "for example", implying there is another.  I don't see it though.
> What else is different?

I'm sure I have encountered error messages about /dev/null permissions
at some point, but I can't reproduce it atm

>> /dev/tty not being group-writable leads to the following
>> error when I login through ssh:
>>  sshd[79]: error: open /dev/tty failed - could not set controlling
>> tty: Permission denied
>
> Interesting.  Mine definately is owned by group tty, and it's not
> userspace changing it after boot, since even
>    lxc-start -n r2 -- /bin/sleep 100
> with lxc.autodev = 1 gets /dev/tty owned by group tty.  I don't
> understand why though as I don't see any place in src/lxc/conf.c where I
> chown it.

That is why I called permissions "strange", quick look at the source
made no insights on what's happening.

> Do you have the same result (just to help me figure out what's going on,
> not to suggest you should have to do this) if you add
>
> lxc.devttydir = lxc

Doing this just moves /dev/console into subdir, but /dev/console has
correct group and permissions regardless of this option.
For /dev/tty and other nodes in question that option does not change anything.

>
> thanks,
> -serge