dev: advertise the new ifindex when the netns iface changes
The goal is to let the user follow an interface that moves to another
netns.
CC: Jiri Benc <jbenc@redhat.com>
CC: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index f111557..e04af7b 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -988,6 +988,7 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev,
+ rtnl_xdp_size() /* IFLA_XDP */
+ nla_total_size(4) /* IFLA_EVENT */
+ nla_total_size(4) /* IFLA_NEW_NETNSID */
+ + nla_total_size(4) /* IFLA_NEW_IFINDEX */
+ nla_total_size(1) /* IFLA_PROTO_DOWN */
+ nla_total_size(4) /* IFLA_IF_NETNSID */
+ nla_total_size(4) /* IFLA_CARRIER_UP_COUNT */
@@ -1511,7 +1512,8 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,
struct net_device *dev, struct net *src_net,
int type, u32 pid, u32 seq, u32 change,
unsigned int flags, u32 ext_filter_mask,
- u32 event, int *new_nsid, int tgt_netnsid)
+ u32 event, int *new_nsid, int new_ifindex,
+ int tgt_netnsid)
{
struct ifinfomsg *ifm;
struct nlmsghdr *nlh;
@@ -1608,6 +1610,10 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,
if (new_nsid &&
nla_put_s32(skb, IFLA_NEW_NETNSID, *new_nsid) < 0)
goto nla_put_failure;
+ if (new_ifindex &&
+ nla_put_s32(skb, IFLA_NEW_IFINDEX, new_ifindex) < 0)
+ goto nla_put_failure;
+
rcu_read_lock();
if (rtnl_fill_link_af(skb, dev, ext_filter_mask))
@@ -1853,7 +1859,7 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, 0,
flags,
- ext_filter_mask, 0, NULL,
+ ext_filter_mask, 0, NULL, 0,
netnsid);
if (err < 0) {
@@ -3088,7 +3094,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh,
err = rtnl_fill_ifinfo(nskb, dev, net,
RTM_NEWLINK, NETLINK_CB(skb).portid,
nlh->nlmsg_seq, 0, 0, ext_filter_mask,
- 0, NULL, netnsid);
+ 0, NULL, 0, netnsid);
if (err < 0) {
/* -EMSGSIZE implies BUG in if_nlmsg_size */
WARN_ON(err == -EMSGSIZE);
@@ -3184,7 +3190,8 @@ static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
struct sk_buff *rtmsg_ifinfo_build_skb(int type, struct net_device *dev,
unsigned int change,
- u32 event, gfp_t flags, int *new_nsid)
+ u32 event, gfp_t flags, int *new_nsid,
+ int new_ifindex)
{
struct net *net = dev_net(dev);
struct sk_buff *skb;
@@ -3197,7 +3204,7 @@ struct sk_buff *rtmsg_ifinfo_build_skb(int type, struct net_device *dev,
err = rtnl_fill_ifinfo(skb, dev, dev_net(dev),
type, 0, 0, change, 0, 0, event,
- new_nsid, -1);
+ new_nsid, new_ifindex, -1);
if (err < 0) {
/* -EMSGSIZE implies BUG in if_nlmsg_size() */
WARN_ON(err == -EMSGSIZE);
@@ -3220,14 +3227,15 @@ void rtmsg_ifinfo_send(struct sk_buff *skb, struct net_device *dev, gfp_t flags)
static void rtmsg_ifinfo_event(int type, struct net_device *dev,
unsigned int change, u32 event,
- gfp_t flags, int *new_nsid)
+ gfp_t flags, int *new_nsid, int new_ifindex)
{
struct sk_buff *skb;
if (dev->reg_state != NETREG_REGISTERED)
return;
- skb = rtmsg_ifinfo_build_skb(type, dev, change, event, flags, new_nsid);
+ skb = rtmsg_ifinfo_build_skb(type, dev, change, event, flags, new_nsid,
+ new_ifindex);
if (skb)
rtmsg_ifinfo_send(skb, dev, flags);
}
@@ -3235,14 +3243,15 @@ static void rtmsg_ifinfo_event(int type, struct net_device *dev,
void rtmsg_ifinfo(int type, struct net_device *dev, unsigned int change,
gfp_t flags)
{
- rtmsg_ifinfo_event(type, dev, change, rtnl_get_event(0), flags, NULL);
+ rtmsg_ifinfo_event(type, dev, change, rtnl_get_event(0), flags,
+ NULL, 0);
}
void rtmsg_ifinfo_newnet(int type, struct net_device *dev, unsigned int change,
- gfp_t flags, int *new_nsid)
+ gfp_t flags, int *new_nsid, int new_ifindex)
{
rtmsg_ifinfo_event(type, dev, change, rtnl_get_event(0), flags,
- new_nsid);
+ new_nsid, new_ifindex);
}
static int nlmsg_populate_fdb_fill(struct sk_buff *skb,
@@ -4642,7 +4651,7 @@ static int rtnetlink_event(struct notifier_block *this, unsigned long event, voi
case NETDEV_CHANGELOWERSTATE:
case NETDEV_CHANGE_TX_QUEUE_LEN:
rtmsg_ifinfo_event(RTM_NEWLINK, dev, 0, rtnl_get_event(event),
- GFP_KERNEL, NULL);
+ GFP_KERNEL, NULL, 0);
break;
default:
break;