path: root/net/ipv4/xfrm4_policy.c
diff options
authorXin Long <lucien.xin@gmail.com>2018-02-14 19:06:02 +0800
committerSteffen Klassert <steffen.klassert@secunet.com>2018-02-16 07:03:33 +0100
commit510c321b557121861601f9d259aadd65aa274f35 (patch)
treecbd373ad6a3c9fe47ba6826ceda698055ae2a4a3 /net/ipv4/xfrm4_policy.c
parentxfrm_user: uncoditionally validate esn replay attribute struct (diff)
xfrm: reuse uncached_list to track xdsts
In early time, when freeing a xdst, it would be inserted into dst_garbage.list first. Then if it's refcnt was still held somewhere, later it would be put into dst_busy_list in dst_gc_task(). When one dev was being unregistered, the dev of these dsts in dst_busy_list would be set with loopback_dev and put this dev. So that this dev's removal wouldn't get blocked, and avoid the kmsg warning: kernel:unregister_netdevice: waiting for veth0 to become \ free. Usage count = 2 However after Commit 52df157f17e5 ("xfrm: take refcnt of dst when creating struct xfrm_dst bundle"), the xdst will not be freed with dst gc, and this warning happens. To fix it, we need to find these xdsts that are still held by others when removing the dev, and free xdst's dev and set it with loopback_dev. But unfortunately after flow_cache for xfrm was deleted, no list tracks them anymore. So we need to save these xdsts somewhere to release the xdst's dev later. To make this easier, this patch is to reuse uncached_list to track xdsts, so that the dev refcnt can be released in the event NETDEV_UNREGISTER process of fib_netdev_notifier. Thanks to Florian, we could move forward this fix quickly. Fixes: 52df157f17e5 ("xfrm: take refcnt of dst when creating struct xfrm_dst bundle") Reported-by: Jianlin Shi <jishi@redhat.com> Reported-by: Hangbin Liu <liuhangbin@gmail.com> Tested-by: Eyal Birger <eyal.birger@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Diffstat (limited to 'net/ipv4/xfrm4_policy.c')
1 files changed, 3 insertions, 1 deletions
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 05017e2c849c..8d33f7b311f4 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -102,6 +102,7 @@ static int xfrm4_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
xdst->u.rt.rt_pmtu = rt->rt_pmtu;
xdst->u.rt.rt_table_id = rt->rt_table_id;
+ rt_add_uncached_list(&xdst->u.rt);
return 0;
@@ -241,7 +242,8 @@ static void xfrm4_dst_destroy(struct dst_entry *dst)
struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+ if (xdst->u.rt.rt_uncached_list)
+ rt_del_uncached_list(&xdst->u.rt);