-stable review patch. If anyone has any objections, please let us know. --------------------- From: James Chapman Upstream commit: e653181dd6b3ad38ce14904351b03a5388f4b0f7 When walking a session's packet reorder queue, use skb_queue_walk_safe() since the list could be modified inside the loop. Rearrange the unlinking skbs from the reorder queue such that it is done while the queue lock is held in pppol2tp_recv_dequeue() when walking the skb list. A version of this patch was suggested by Jarek Poplawski. Signed-off-by: James Chapman Signed-off-by: David S. Miller Signed-off-by: Chris Wright --- drivers/net/pppol2tp.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) --- a/drivers/net/pppol2tp.c +++ b/drivers/net/pppol2tp.c @@ -342,10 +342,11 @@ static struct pppol2tp_tunnel *pppol2tp_ static void pppol2tp_recv_queue_skb(struct pppol2tp_session *session, struct sk_buff *skb) { struct sk_buff *skbp; + struct sk_buff *tmp; u16 ns = PPPOL2TP_SKB_CB(skb)->ns; spin_lock_bh(&session->reorder_q.lock); - skb_queue_walk(&session->reorder_q, skbp) { + skb_queue_walk_safe(&session->reorder_q, skbp, tmp) { if (PPPOL2TP_SKB_CB(skbp)->ns > ns) { __skb_insert(skb, skbp->prev, skbp, &session->reorder_q); PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG, @@ -371,10 +372,9 @@ static void pppol2tp_recv_dequeue_skb(st int length = PPPOL2TP_SKB_CB(skb)->length; struct sock *session_sock = NULL; - /* We're about to requeue the skb, so unlink it and return resources + /* We're about to requeue the skb, so return resources * to its current owner (a socket receive buffer). */ - skb_unlink(skb, &session->reorder_q); skb_orphan(skb); tunnel->stats.rx_packets++; @@ -469,6 +469,11 @@ static void pppol2tp_recv_dequeue(struct goto out; } } + __skb_unlink(skb, &session->reorder_q); + + /* Process the skb. We release the queue lock while we + * do so to let other contexts process the queue. + */ spin_unlock_bh(&session->reorder_q.lock); pppol2tp_recv_dequeue_skb(session, skb); spin_lock_bh(&session->reorder_q.lock); -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/