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| author | Cong Wang <cong.wang@bytedance.com> | 2020-11-20 19:43:17 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-12-02 08:49:44 +0100 |
| commit | 6ec51459df7117dbe9b1fef2174951f80877a850 (patch) | |
| tree | 2fdba2da3264b1a0c24a458e5448688d38be5868 | |
| parent | ee791835b3ec78178ca4c592368fa26d48dea5fa (diff) | |
| download | linux-6ec51459df7117dbe9b1fef2174951f80877a850.tar.gz | |
netfilter: clear skb->next in NF_HOOK_LIST()
NF_HOOK_LIST() uses list_del() to remove skb from the linked list,
however, it is not sufficient as skb->next still points to other
skb. We should just call skb_list_del_init() to clear skb->next,
like the rest places which using skb list.
This has been fixed in upstream by commit ca58fbe06c54
("netfilter: add and use nf_hook_slow_list()").
Fixes: 9f17dbf04ddf ("netfilter: fix use-after-free in NF_HOOK_LIST")
Reported-by: liuzx@knownsec.com
Tested-by: liuzx@knownsec.com
Cc: Florian Westphal <fw@strlen.de>
Cc: Edward Cree <ecree@solarflare.com>
Cc: stable@vger.kernel.org # between 4.19 and 5.4
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | include/linux/netfilter.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index 77ebb61faf4863..4c0e6539effddb 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -316,7 +316,7 @@ NF_HOOK_LIST(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, INIT_LIST_HEAD(&sublist); list_for_each_entry_safe(skb, next, head, list) { - list_del(&skb->list); + skb_list_del_init(skb); if (nf_hook(pf, hook, net, sk, skb, in, out, okfn) == 1) list_add_tail(&skb->list, &sublist); } |