From 34e02aa1fb0886d8e92ab00e3dc17d631487f92d Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Tue, 9 Oct 2012 20:35:53 +0000 Subject: [PATCH] vxlan: fix oops when give unknown ifindex If vxlan is created and the ifindex is passed; there are two cases which are incorrectly handled by the existing code. The ifindex could be zero (i.e. no device) or there could be no device with that ifindex. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- drivers/net/vxlan.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 763061d97921..607976c00162 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -1090,14 +1090,18 @@ static int vxlan_newlink(struct net *net, struct net_device *dev, if (data[IFLA_VXLAN_LOCAL]) vxlan->saddr = nla_get_be32(data[IFLA_VXLAN_LOCAL]); - if (data[IFLA_VXLAN_LINK]) { - vxlan->link = nla_get_u32(data[IFLA_VXLAN_LINK]); + if (data[IFLA_VXLAN_LINK] && + (vxlan->link = nla_get_u32(data[IFLA_VXLAN_LINK]))) { + struct net_device *lowerdev + = __dev_get_by_index(net, vxlan->link); - if (!tb[IFLA_MTU]) { - struct net_device *lowerdev; - lowerdev = __dev_get_by_index(net, vxlan->link); - dev->mtu = lowerdev->mtu - VXLAN_HEADROOM; + if (!lowerdev) { + pr_info("ifindex %d does not exist\n", vxlan->link); + return -ENODEV; } + + if (!tb[IFLA_MTU]) + dev->mtu = lowerdev->mtu - VXLAN_HEADROOM; } if (data[IFLA_VXLAN_TOS])