The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 69e766612c4bcb79e19cebed9eed61d4222c1d47 Mon Sep 17 00:00:00 2001
From: Jiri Benc <jbenc@xxxxxxxxxx>
Date: Sun, 2 Jul 2017 19:00:57 +0200
Subject: [PATCH] vxlan: fix hlist corruption
It's not a good idea to add the same hlist_node to two different hash lists.
This leads to various hard to debug memory corruptions.
Fixes: b1be00a6c39f ("vxlan: support both IPv4 and IPv6 sockets in a single vxlan device")
Signed-off-by: Jiri Benc <jbenc@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 47d6e65851aa..b04e103350fb 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -229,25 +229,25 @@ static struct vxlan_sock *vxlan_find_sock(struct net *net, sa_family_t family,
static struct vxlan_dev *vxlan_vs_find_vni(struct vxlan_sock *vs, int ifindex,
__be32 vni)
{
- struct vxlan_dev *vxlan;
+ struct vxlan_dev_node *node;
/* For flow based devices, map all packets to VNI 0 */
if (vs->flags & VXLAN_F_COLLECT_METADATA)
vni = 0;
- hlist_for_each_entry_rcu(vxlan, vni_head(vs, vni), hlist) {
- if (vxlan->default_dst.remote_vni != vni)
+ hlist_for_each_entry_rcu(node, vni_head(vs, vni), hlist) {
+ if (node->vxlan->default_dst.remote_vni != vni)
continue;
if (IS_ENABLED(CONFIG_IPV6)) {
- const struct vxlan_config *cfg = &vxlan->cfg;
+ const struct vxlan_config *cfg = &node->vxlan->cfg;
if ((cfg->flags & VXLAN_F_IPV6_LINKLOCAL) &&
cfg->remote_ifindex != ifindex)
continue;
}
- return vxlan;
+ return node->vxlan;
}
return NULL;
@@ -2387,17 +2387,22 @@ static void vxlan_vs_del_dev(struct vxlan_dev *vxlan)
struct vxlan_net *vn = net_generic(vxlan->net, vxlan_net_id);
spin_lock(&vn->sock_lock);
- hlist_del_init_rcu(&vxlan->hlist);
+ hlist_del_init_rcu(&vxlan->hlist4.hlist);
+#if IS_ENABLED(CONFIG_IPV6)
+ hlist_del_init_rcu(&vxlan->hlist6.hlist);
+#endif
spin_unlock(&vn->sock_lock);
}
-static void vxlan_vs_add_dev(struct vxlan_sock *vs, struct vxlan_dev *vxlan)
+static void vxlan_vs_add_dev(struct vxlan_sock *vs, struct vxlan_dev *vxlan,
+ struct vxlan_dev_node *node)
{
struct vxlan_net *vn = net_generic(vxlan->net, vxlan_net_id);
__be32 vni = vxlan->default_dst.remote_vni;
+ node->vxlan = vxlan;
spin_lock(&vn->sock_lock);
- hlist_add_head_rcu(&vxlan->hlist, vni_head(vs, vni));
+ hlist_add_head_rcu(&node->hlist, vni_head(vs, vni));
spin_unlock(&vn->sock_lock);
}
@@ -2849,6 +2854,7 @@ static int __vxlan_sock_add(struct vxlan_dev *vxlan, bool ipv6)
{
struct vxlan_net *vn = net_generic(vxlan->net, vxlan_net_id);
struct vxlan_sock *vs = NULL;
+ struct vxlan_dev_node *node;
if (!vxlan->cfg.no_share) {
spin_lock(&vn->sock_lock);
@@ -2866,12 +2872,16 @@ static int __vxlan_sock_add(struct vxlan_dev *vxlan, bool ipv6)
if (IS_ERR(vs))
return PTR_ERR(vs);
#if IS_ENABLED(CONFIG_IPV6)
- if (ipv6)
+ if (ipv6) {
rcu_assign_pointer(vxlan->vn6_sock, vs);
- else
+ node = &vxlan->hlist6;
+ } else
#endif
+ {
rcu_assign_pointer(vxlan->vn4_sock, vs);
- vxlan_vs_add_dev(vs, vxlan);
+ node = &vxlan->hlist4;
+ }
+ vxlan_vs_add_dev(vs, vxlan, node);
return 0;
}
diff --git a/include/net/vxlan.h b/include/net/vxlan.h
index b816a0a6686e..326e8498b10e 100644
--- a/include/net/vxlan.h
+++ b/include/net/vxlan.h
@@ -221,9 +221,17 @@ struct vxlan_config {
bool no_share;
};
+struct vxlan_dev_node {
+ struct hlist_node hlist;
+ struct vxlan_dev *vxlan;
+};
+
/* Pseudo network device */
struct vxlan_dev {
- struct hlist_node hlist; /* vni hash table */
+ struct vxlan_dev_node hlist4; /* vni hash table for IPv4 socket */
+#if IS_ENABLED(CONFIG_IPV6)
+ struct vxlan_dev_node hlist6; /* vni hash table for IPv6 socket */
+#endif
struct list_head next; /* vxlan's per namespace list */
struct vxlan_sock __rcu *vn4_sock; /* listening socket for IPv4 */
#if IS_ENABLED(CONFIG_IPV6)