The patch below does not apply to the 4.4-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 610f8c0fc8d46e0933955ce13af3d64484a4630a Mon Sep 17 00:00:00 2001
From: Hristo Venev <hristo@xxxxxxxxxx>
Date: Mon, 12 Apr 2021 20:41:16 +0300
Subject: [PATCH] net: sit: Unregister catch-all devices
A sit interface created without a local or a remote address is linked
into the `sit_net::tunnels_wc` list of its original namespace. When
deleting a network namespace, delete the devices that have been moved.
The following script triggers a null pointer dereference if devices
linked in a deleted `sit_net` remain:
for i in `seq 1 30`; do
ip netns add ns-test
ip netns exec ns-test ip link add dev veth0 type veth peer veth1
ip netns exec ns-test ip link add dev sit$i type sit dev veth0
ip netns exec ns-test ip link set dev sit$i netns $$
ip netns del ns-test
done
for i in `seq 1 30`; do
ip link del dev sit$i
done
Fixes: 5e6700b3bf98f ("sit: add support of x-netns")
Signed-off-by: Hristo Venev <hristo@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 63ccd9f2dccc..9fdccf0718b5 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -1867,9 +1867,9 @@ static void __net_exit sit_destroy_tunnels(struct net *net,
if (dev->rtnl_link_ops == &sit_link_ops)
unregister_netdevice_queue(dev, head);
- for (prio = 1; prio < 4; prio++) {
+ for (prio = 0; prio < 4; prio++) {
int h;
- for (h = 0; h < IP6_SIT_HASH_SIZE; h++) {
+ for (h = 0; h < (prio ? IP6_SIT_HASH_SIZE : 1); h++) {
struct ip_tunnel *t;
t = rtnl_dereference(sitn->tunnels[prio][h]);
