diff options
author | Yang Yingliang <yangyingliang@huawei.com> | 2022-08-22 10:53:46 +0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2022-08-24 09:49:20 +0100 |
commit | d5485d9dd24e1d04e5509916515260186eb1455c (patch) | |
tree | 51de6d241f5d5dd53a5bfa36b5762eff45765f2c /net | |
parent | 550e9a4d858ff0bf872522eb4a802d549b45ac96 (diff) |
net: neigh: don't call kfree_skb() under spin_lock_irqsave()
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>
Diffstat (limited to 'net')
-rw-r--r-- | net/core/neighbour.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 5b669eb80270..78cc8fb68814 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -309,14 +309,17 @@ 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); struct net_device *dev = skb->dev; + if (net == NULL || net_eq(dev_net(dev), net)) { struct in_device *in_dev; @@ -326,13 +329,16 @@ static void pneigh_queue_purge(struct sk_buff_head *list, struct net *net) in_dev->arp_parms->qlen--; rcu_read_unlock(); __skb_unlink(skb, list); - - dev_put(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, |