From 8712c58ab896f072cf95e3ffa3ceac1fa10f6295 Mon Sep 17 00:00:00 2001 From: Bogdan Purcareata Date: Thu, 14 Nov 2013 12:31:55 +0200 Subject: [PATCH] setup_netdev: re-read ifindex in LXC_NET_PHYS case When moving an interface from the host netns to a container's, the ifindex might not remain the same. This happens when the index of the host interface is already assigned to another interface in the new netns. For veth/vlan/macvlan, virtual interfaces are first created on the host, and then moved in the container. Since they are created after all other interfaces are discovered, there is no chance for its assigned ifindex to be already present in a freshly created netns, since its a greater number. However, when moving a physical interface, there is a chance that its ifindex in the host netns is not free in the new netns. The patch forces ifindex re-read for the LXC_NET_PHYS case to update the lxc_netdev structure. Signed-off-by: Bogdan Purcareata Signed-off-by: Serge Hallyn --- src/lxc/conf.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/src/lxc/conf.c b/src/lxc/conf.c index 6b3f318..08b0d0f 100644 --- a/src/lxc/conf.c +++ b/src/lxc/conf.c @@ -1846,6 +1846,14 @@ static int setup_netdev(struct lxc_netdev *netdev) return 0; } + /* get the new ifindex in case of physical netdev */ + if (netdev->type == LXC_NET_PHYS) + if (!(netdev->ifindex = if_nametoindex(netdev->link))) { + ERROR("failed to get ifindex for %s", + netdev->link); + return -1; + } + /* retrieve the name of the interface */ if (!if_indextoname(netdev->ifindex, current_ifname)) { ERROR("no interface corresponding to index '%d'", -- 1.7.11.7