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So replace kfree_skb() > with dev_kfree_skb_irq() under spin_lock_irqsave(). > > Fixes: 66ba215cb513 ("neigh: fix possible DoS due to net iface start/stop loop") > Signed-off-by: Yang Yingliang > --- > net/core/neighbour.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/core/neighbour.c b/net/core/neighbour.c > index 5b669eb80270..167826200f3e 100644 > --- a/net/core/neighbour.c > +++ b/net/core/neighbour.c > @@ -328,7 +328,7 @@ static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net) > __skb_unlink(skb, list); > > dev_put(dev); > - kfree_skb(skb); > + dev_kfree_skb_irq(skb); > } > skb = skb_next; > } Technically this is pretty much correct, but would it be better to move all skb to purge into the new list and after that purge them at once? what about something like this? diff --git a/net/core/neighbour.c b/net/core/neighbour.c index aa16a8017c5e..f7e30daa46ae 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -311,6 +311,9 @@ static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net)  {         unsigned long flags;         struct sk_buff *skb; +       struct sk_buff_head tmp; + +       skb_queue_head_init(&tmp);         spin_lock_irqsave(&list->lock, flags);         skb = skb_peek(list); @@ -318,12 +321,16 @@ static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net)                 struct sk_buff *skb_next = skb_peek_next(skb, list);                 if (net == NULL || net == dev_net(skb->dev)) {                         __skb_unlink(skb, list); -                       dev_put(skb->dev); -                       kfree_skb(skb); +                       __skb_queue_tail(&tmp, skb);                 }                 skb = skb_next;         } while (skb != NULL);         spin_unlock_irqrestore(&list->lock, flags); + +       while ((skb = __skb_dequeue(&tmp)) != NULL) { +               dev_put(skb->dev); +               kfree_skb(skb); +       }  } iris ~/src/linux-2.6 $