From c2f17e827b419918c856131f592df9521e1a38e3 Mon Sep 17 00:00:00 2001 From: Hannes Frederic Sowa Date: Mon, 21 Oct 2013 06:17:15 +0200 Subject: [PATCH] ipv6: probe routes asynchronous in rt6_probe Routes need to be probed asynchronous otherwise the call stack gets exhausted when the kernel attemps to deliver another skb inline, like e.g. xt_TEE does, and we probe at the same time. We update neigh->updated still at once, otherwise we would send to many probes. Cc: Julian Anastasov Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- net/ipv6/route.c | 40 ++++++++++++++++++++++++++++++++-------- 1 file changed, 32 insertions(+), 8 deletions(-) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index c1ee3813e1ae..f54e3a101098 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -476,6 +476,24 @@ out: } #ifdef CONFIG_IPV6_ROUTER_PREF +struct __rt6_probe_work { + struct work_struct work; + struct in6_addr target; + struct net_device *dev; +}; + +static void rt6_probe_deferred(struct work_struct *w) +{ + struct in6_addr mcaddr; + struct __rt6_probe_work *work = + container_of(w, struct __rt6_probe_work, work); + + addrconf_addr_solict_mult(&work->target, &mcaddr); + ndisc_send_ns(work->dev, NULL, &work->target, &mcaddr, NULL); + dev_put(work->dev); + kfree(w); +} + static void rt6_probe(struct rt6_info *rt) { struct neighbour *neigh; @@ -499,17 +517,23 @@ static void rt6_probe(struct rt6_info *rt) if (!neigh || time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) { - struct in6_addr mcaddr; - struct in6_addr *target; + struct __rt6_probe_work *work; - if (neigh) { + work = kmalloc(sizeof(*work), GFP_ATOMIC); + + if (neigh && work) neigh->updated = jiffies; - write_unlock(&neigh->lock); - } - target = (struct in6_addr *)&rt->rt6i_gateway; - addrconf_addr_solict_mult(target, &mcaddr); - ndisc_send_ns(rt->dst.dev, NULL, target, &mcaddr, NULL); + if (neigh) + write_unlock(&neigh->lock); + + if (work) { + INIT_WORK(&work->work, rt6_probe_deferred); + work->target = rt->rt6i_gateway; + dev_hold(rt->dst.dev); + work->dev = rt->dst.dev; + schedule_work(&work->work); + } } else { out: write_unlock(&neigh->lock);