From ff3532f2655b79058fec035ca54fced69a483084 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 17 Jul 2015 22:38:44 +0200 Subject: [PATCH] sched: cls_flower: fix panic on filter replace The following test case causes a NULL pointer dereference in cls_flower: tc filter add dev foo parent 1: flower eth_type ipv4 action ok flowid 1:1 tc filter replace dev foo parent 1: pref 49152 handle 0x1 \ flower eth_type ipv6 action ok flowid 1:1 The problem is that commit 77b9900ef53a ("tc: introduce Flower classifier") accidentally swapped the arguments of list_replace_rcu(), the old element needs to be the first argument and the new element the second. Fixes: 77b9900ef53a ("tc: introduce Flower classifier") Signed-off-by: Daniel Borkmann Acked-by: Jiri Pirko Signed-off-by: David S. Miller --- net/sched/cls_flower.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index 9d37ccd95062..2f3d03f99487 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -499,7 +499,7 @@ static int fl_change(struct net *net, struct sk_buff *in_skb, *arg = (unsigned long) fnew; if (fold) { - list_replace_rcu(&fnew->list, &fold->list); + list_replace_rcu(&fold->list, &fnew->list); tcf_unbind_filter(tp, &fold->res); call_rcu(&fold->rcu, fl_destroy_filter); } else {