4.4-stable review patch. If anyone has any objections, please let me know.
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From: Nicolas Dichtel nicolas.dichtel@6wind.com
[ Upstream commit 35b827b6d06199841a83839e8bb69c0cd13a28be ]
It's not supported right now (the goal of the initial patch was to support 'ip link del' only).
Before the patch: $ ip link add foo type tun [ 239.632660] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 [snip] [ 239.636410] RIP: 0010:register_netdevice+0x8e/0x3a0
This panic occurs because dev->netdev_ops is not set by tun_setup(). But to have something usable, it will require more than just setting netdev_ops.
Fixes: f019a7a594d9 ("tun: Implement ip link del tunXXX") CC: Eric W. Biederman ebiederm@xmission.com Signed-off-by: Nicolas Dichtel nicolas.dichtel@6wind.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/tun.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1475,9 +1475,9 @@ static void tun_setup(struct net_device */ static int tun_validate(struct nlattr *tb[], struct nlattr *data[]) { - if (!data) - return 0; - return -EINVAL; + /* NL_SET_ERR_MSG(extack, + "tun/tap creation via rtnetlink is not supported."); */ + return -EOPNOTSUPP; }
static struct rtnl_link_ops tun_link_ops __read_mostly = {