From 41a230fef787315d982dd915ef2a33a136e9a1d5 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Tue, 29 Oct 2019 01:24:32 +0800 Subject: vxlan: check tun_info options_len properly [ Upstream commit eadf52cf1852196a1363044dcda22fa5d7f296f7 ] This patch is to improve the tun_info options_len by dropping the skb when TUNNEL_VXLAN_OPT is set but options_len is less than vxlan_metadata. This can void a potential out-of-bounds access on ip_tun_info. Fixes: ee122c79d422 ("vxlan: Flow based tunneling") Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/vxlan.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers/net/vxlan.c') diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 2fbaa279988e..6d26bbd190dd 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -2169,8 +2169,11 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, vni = tunnel_id_to_key32(info->key.tun_id); ifindex = 0; dst_cache = &info->dst_cache; - if (info->options_len) + if (info->options_len) { + if (info->options_len < sizeof(*md)) + goto drop; md = ip_tunnel_info_opts(info); + } ttl = info->key.ttl; tos = info->key.tos; label = info->key.label; -- cgit v1.2.3 From 9ab07796de822dced31e4522ee1b4691b14c3cf9 Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Tue, 18 Dec 2018 13:16:00 +0000 Subject: vxlan: Fix error path in __vxlan_dev_create() [ Upstream commit 6db9246871394b3a136cd52001a0763676563840 ] When a failure occurs in rtnl_configure_link(), the current code calls unregister_netdevice() to roll back the earlier call to register_netdevice(), and jumps to errout, which calls vxlan_fdb_destroy(). However unregister_netdevice() calls transitively ndo_uninit, which is vxlan_uninit(), and that already takes care of deleting the default FDB entry by calling vxlan_fdb_delete_default(). Since the entry added earlier in __vxlan_dev_create() is exactly the default entry, the cleanup code in the errout block always leads to double free and thus a panic. Besides, since vxlan_fdb_delete_default() always destroys the FDB entry with notification enabled, the deletion of the default entry is notified even before the addition was notified. Instead, move the unregister_netdevice() call after the manual destroy, which solves both problems. Fixes: 0241b836732f ("vxlan: fix default fdb entry netlink notify ordering during netdev create") Signed-off-by: Petr Machata Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/vxlan.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'drivers/net/vxlan.c') diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 6d26bbd190dd..153a81ece9fe 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -3217,6 +3217,7 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev, struct vxlan_net *vn = net_generic(net, vxlan_net_id); struct vxlan_dev *vxlan = netdev_priv(dev); struct vxlan_fdb *f = NULL; + bool unregister = false; int err; err = vxlan_dev_configure(net, dev, conf, false, extack); @@ -3242,12 +3243,11 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev, err = register_netdevice(dev); if (err) goto errout; + unregister = true; err = rtnl_configure_link(dev, NULL); - if (err) { - unregister_netdevice(dev); + if (err) goto errout; - } /* notify default fdb entry */ if (f) @@ -3255,9 +3255,16 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev, list_add(&vxlan->next, &vn->vxlan_list); return 0; + errout: + /* unregister_netdevice() destroys the default FDB entry with deletion + * notification. But the addition notification was not sent yet, so + * destroy the entry by hand here. + */ if (f) vxlan_fdb_destroy(vxlan, f, false); + if (unregister) + unregister_netdevice(dev); return err; } -- cgit v1.2.3