Re: [PATCH iproute2 v1] ip netns: allow negative nsid

[Christian Brauner <christian.brauner@canonical.com>]

On Thu, Feb 8, 2018 at 5:01 PM, Stephen Hemminger
<stephen@networkplumber.org> wrote:
> On Tue,  6 Feb 2018 19:39:31 +0100
> Christian Brauner <christian.brauner@ubuntu.com> wrote:
>
>> If the kernel receives a negative nsid it will automatically assign the
>> next available nsid. In this case alloc_netid() will set min and max to
>> 0 for ird_alloc(). And when max == 0 idr_alloc() will interpret this as
>> the maxium range, i.e. specific to nsids it will try to find an id in
>> the range [0,INT_MAX). This is intentionally supported in the kernel for
>> nsids. Commit acbe9118ce8086f765ffb0da15f80c7c01a8903a regressed ip
>> netns in that respect although previously the use-case was either
>> accidentally supported or opaquely supported such that it triggered the
>> original commit. From what I can gather it went as follows before:
>> atoi() was called with a string indicating a negative value which caused
>> it to return -1 which was passed to the kernel. Let's make it less
>> opaque by introducing the keyword "auto":
>>
>> ip netns set <netns-name> auto
>>
>> will cause nsid to be set to -1 and the kernel will select an available
>> nsid.
>>
>> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
>
> Applied thank you.
> I did have to fix spelling and format of commit reference in
> the commit description. If you run checkpatch on patches to
> iproute you would have caught that.

Ah, sorry about that. Didn't think about applying checkpatch to iproute
patches as well. Won't happen again!

Thanks for applying.
Christian