Commit 997d5c3f authored Feb 18, 2015 by Eric Dumazet Committed by David S. Miller Feb 20, 2015

sock: sock_dequeue_err_skb() needs hard irq safety



Non NAPI drivers can call skb_tstamp_tx() and then sock_queue_err_skb()
from hard IRQ context.

Therefore, sock_dequeue_err_skb() needs to block hard irq or
corruptions or hangs can happen.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 364a9e93 ("sock: deduplicate errqueue dequeue")
Fixes: cb820f8e ("net: Provide a generic socket error queue delivery method for Tx time stamps.")
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 846cd667

net/core/skbuff.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -3621,13 +3621,14 @@ struct sk_buff sock_dequeue_err_skb(struct sock sk)
		{
		struct sk_buff_head *q = &sk->sk_error_queue;
		struct sk_buff skb, skb_next;
		unsigned long flags;
		int err = 0;

		spin_lock_bh(&q->lock);
		spin_lock_irqsave(&q->lock, flags);
		skb = __skb_dequeue(q);
		if (skb && (skb_next = skb_peek(q)))
		err = SKB_EXT_ERR(skb_next)->ee.ee_errno;
		spin_unlock_bh(&q->lock);
		spin_unlock_irqrestore(&q->lock, flags);

		sk->sk_err = err;
		if (err)