unable to set allowed-ips

[Thomas Sattler]

Am 24.03.2017 um 02:15 schrieb Jason A. Donenfeld:
> Be sure userland wg(8) is built from the same source as kernel
> land wireguard module.

I'm not sure whether I understood that comment, but in case I did:
I cloned  https://git.zx2c4.com/WireGuard  and then run these two
commands:

  $ cd /usr/src/WireGuard/src/tools && make

and

  $ cd /usr/src/linux && 
/usr/src/WireGuard/contrib/kernel-tree/create-patch.sh | patch -sp1

The obvious difference seems to be that I used different compilers for
them:

  - sys-devel/gcc-4.9.4 for wg(8) and
  - cross-x86_64-pc-linux-gnu/gcc-4.9.4 for the kernel

Just in case the compiler is not the cause: Maybe my kernel config is
the problem? While I double checked to have everything activated that
was mentioned at https://www.wireguard.io/install (except IPv6 stuff)
there might be some other feature I have unset or set incompatible?

Thomas