tree ebdd9dd63fce91fec7a5ba8a2f4e5d56738dac0b
parent 810d8cedcc880dca8b64e05fe1331ab5d4f8d992
author Nicolas Dichtel <nicolas.dichtel@6wind.com> 1397224278 +0200
committer David S. Miller <davem@davemloft.net> 1397336591 -0400

gre: don't allow to add the same tunnel twice

Before the patch, it was possible to add two times the same tunnel:
ip l a gre1 type gre remote 10.16.0.121 local 10.16.0.249
ip l a gre2 type gre remote 10.16.0.121 local 10.16.0.249

It was possible, because ip_tunnel_newlink() calls ip_tunnel_find() with the
argument dev->type, which was set only later (when calling ndo_init handler
in register_netdevice()). Let's set this type in the setup handler, which is
called before newlink handler.

Introduced by commit c54419321455 ("GRE: Refactor GRE tunneling code.").

CC: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>