[CRIU] Can't launch unshare with -U or -r as unprivileged user

[Allan Cecil]

On 06/04/2014 10:26 AM, Christopher Covington wrote:
> On 06/04/2014 01:16 PM, Christopher Covington wrote:
~snip~
>> So after my digression it comes back to the question of how to get `unshare
>> -r` to work. I noticed that in a kernel where CONFIG_USER_NS is not set, I was
>> getting the "Invalid argument" error there when trying stuff like `unshare -r
>> -- echo hello` or the example given in the patch introducing the -r option [1].
>>
>> 1. http://thread.gmane.org/gmane.linux.utilities.util-linux-ng/8317
>>
>> Is there a /boot/config or /proc/config.gz that you can use to confirm
>> CONFIG_USER_NS=y?
>>
>> Being entirely new to the subject, I found the following thread interesting
>> background information.
>>
>> https://lists.linux-foundation.org/pipermail/containers/2013-June/032727.html
> 
> Digging further, it looks like CONFIG_USER_NS was dropped in Ubuntu 12.10
> Quantal and reinstated in 14.04 Trusty. Maybe that upgrade to Mint 17 is a
> prerequisite?
> 
> https://bugs.launchpad.net/bugs/1191600
> https://wiki.ubuntu.com/Kernel/Configs/PreciseToQuantal
> https://wiki.ubuntu.com/Kernel/Configs/SaucyToTrusty
> 
> Christopher 

Hmm...  I did a cat /boot/config-3.11.0-19-generic | grep CONFIG_USER_NS and that flag was not found.  Assuming I have the right file I think I need to upgrade.  I just checked and this system is actually based on the Linux Mint Cinnamon edition (albeit with xfce installed), so I should be able to upgrade right away.  I will work on that this tonight or later this week and get back to you with the results of trying with a new kernel.  Thank you very much for your assistance,

A.C.
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