Re: [PATCH v2] inotify: Convert to using per-namespace limits

[Eric W. Biederman]

Nikolay Borisov <kernel@xxxxxxxx> writes:

> On 10/11/2016 10:36 AM, Nikolay Borisov wrote:
>> This patchset converts inotify to using the newly introduced
>> per-userns sysctl infrastructure.
>> 
>> Currently the inotify instances/watches are being accounted in the
>> user_struct structure. This means that in setups where multiple
>> users in unprivileged containers map to the same underlying
>> real user (i.e. pointing to the same user_struct) the inotify limits
>> are going to be shared as well, allowing one user(or application) to exhaust
>> all others limits.
>> 
>> Fix this by switching the inotify sysctls to using the
>> per-namespace/per-user limits. This will allow the server admin to
>> set sensible global limits, which can further be tuned inside every
>> individual user namespace. Additionally, in order to preserve the
>> sysctl ABI make the existing inotify instances/watches sysctls
>> modify the values of the initial user namespace.
>> 
>> Signed-off-by: Nikolay Borisov <kernel@xxxxxxxx>
>> ---
>> 
>> So here is a revised version which retains the existing sysctls,
>> and hooks them to the init_user_ns values. 
>
> Gentle ping, now that rc1 has shipped and Jan's sysctl concern hopefully
> resolved.

I plan to give this a once over and merge this.  I have a very funny
pile of serious bug fixes that jumped on my at the beginning of this
development cycle and a cold so I am getting to this more slowly than I
would like.

Eric