diff options
| author | Yang Yingliang <yangyingliang@huawei.com> | 2022-08-22 10:53:46 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-09-05 10:27:48 +0200 |
| commit | 0052348329c94f6c608ff0d5372c48e3ab1f4ba8 (patch) | |
| tree | 1cd27a3f21b1856deb17615a76f02b94b7ca7e3a | |
| parent | 25a80e728412739bf39f02d834c7688a1c1abe07 (diff) | |
net: neigh: don't call kfree_skb() under spin_lock_irqsave()
commit d5485d9dd24e1d04e5509916515260186eb1455c upstream.
It is not allowed to call kfree_skb() from hardware interrupt
context or with interrupts being disabled. So add all skb to
a tmp list, then free them after spin_unlock_irqrestore() at
once.
Fixes: 66ba215cb513 ("neigh: fix possible DoS due to net iface start/stop loop")
Suggested-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/core/neighbour.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 6056b8e54565..aa81aead0a65 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -282,21 +282,27 @@ static int neigh_del_timer(struct neighbour *n) static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net) { + struct sk_buff_head tmp; unsigned long flags; struct sk_buff *skb; + skb_queue_head_init(&tmp); spin_lock_irqsave(&list->lock, flags); skb = skb_peek(list); while (skb != NULL) { struct sk_buff *skb_next = skb_peek_next(skb, list); if (net == NULL || net_eq(dev_net(skb->dev), net)) { __skb_unlink(skb, list); - dev_put(skb->dev); - kfree_skb(skb); + __skb_queue_tail(&tmp, skb); } skb = skb_next; } spin_unlock_irqrestore(&list->lock, flags); + + while ((skb = __skb_dequeue(&tmp))) { + dev_put(skb->dev); + kfree_skb(skb); + } } static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev, |