net: core: fix use-after-free in __netif_receive_skb_list_core

__netif_receive_skb_core can free the skb, so we have to use the dequeue-
 enqueue model when calling it from __netif_receive_skb_list_core.

Fixes: 88eb1944e1 ("net: core: propagate SKB lists through packet_type lookup")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Edward Cree 2018-07-09 18:10:19 +01:00 committed by David S. Miller
parent 9f17dbf04d
commit 9af86f9338

View File

@ -4830,23 +4830,28 @@ static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemallo
struct list_head sublist;
struct sk_buff *skb, *next;
INIT_LIST_HEAD(&sublist);
list_for_each_entry_safe(skb, next, head, list) {
struct net_device *orig_dev = skb->dev;
struct packet_type *pt_prev = NULL;
list_del(&skb->list);
__netif_receive_skb_core(skb, pfmemalloc, &pt_prev);
if (!pt_prev)
continue;
if (pt_curr != pt_prev || od_curr != orig_dev) {
/* dispatch old sublist */
list_cut_before(&sublist, head, &skb->list);
__netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr);
/* start new sublist */
INIT_LIST_HEAD(&sublist);
pt_curr = pt_prev;
od_curr = orig_dev;
}
list_add_tail(&skb->list, &sublist);
}
/* dispatch final sublist */
__netif_receive_skb_list_ptype(head, pt_curr, od_curr);
__netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr);
}
static int __netif_receive_skb(struct sk_buff *skb)