diff options
| author | Edward Cree <ecree@solarflare.com> | 2018-07-09 18:10:02 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-07-09 14:55:53 -0700 |
| commit | 9f17dbf04ddf55ae48f5bbafea4c4920ea943215 (patch) | |
| tree | 0e2468ae6bb598bdba17d3679d74c9b00a8034b6 /include | |
| parent | 8c057efaebb557b60ba514b5e39e8000a1eab0f1 (diff) | |
| download | linux-9f17dbf04ddf55ae48f5bbafea4c4920ea943215.tar.bz2 | |
netfilter: fix use-after-free in NF_HOOK_LIST
nf_hook() can free the skb, so we need to remove it from the list before
calling, and add passed skbs to a sublist afterwards.
Fixes: 17266ee93984 ("net: ipv4: listified version of ip_rcv")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/netfilter.h | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index 5a5e0a2ab2a3..23b48de8c2e2 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -294,12 +294,16 @@ NF_HOOK_LIST(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, int (*okfn)(struct net *, struct sock *, struct sk_buff *)) { struct sk_buff *skb, *next; + struct list_head sublist; + INIT_LIST_HEAD(&sublist); list_for_each_entry_safe(skb, next, head, list) { - int ret = nf_hook(pf, hook, net, sk, skb, in, out, okfn); - if (ret != 1) - list_del(&skb->list); + list_del(&skb->list); + if (nf_hook(pf, hook, net, sk, skb, in, out, okfn) == 1) + list_add_tail(&skb->list, &sublist); } + /* Put passed packets back on main list */ + list_splice(&sublist, head); } /* Call setsockopt() */ |