From: Victor Nogueira <victor@xxxxxxxxxxxx> [ Upstream commit e8d3d78c19be0264a5692bed477c303523aead31 ] In the case of an update, when TCA_U32_LINK is set, u32_set_parms will decrement the refcount of the ht_down (struct tc_u_hnode) pointer present in the older u32 filter which we are replacing. However, if u32_replace_hw_knode errors out, the update command fails and that ht_down pointer continues decremented. To fix that, when u32_replace_hw_knode fails, check if ht_down's refcount was decremented and undo the decrement. Fixes: d34e3e181395 ("net: cls_u32: Add support for skip-sw flag to tc u32 classifier.") Signed-off-by: Victor Nogueira <victor@xxxxxxxxxxxx> Acked-by: Jamal Hadi Salim <jhs@xxxxxxxxxxxx> Reviewed-by: Pedro Tammela <pctammela@xxxxxxxxxxxx> Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/sched/cls_u32.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c index 7cfbcd5180841..1280736a7b92e 100644 --- a/net/sched/cls_u32.c +++ b/net/sched/cls_u32.c @@ -926,6 +926,13 @@ static int u32_change(struct net *net, struct sk_buff *in_skb, if (err) { u32_unbind_filter(tp, new, tb); + if (tb[TCA_U32_LINK]) { + struct tc_u_hnode *ht_old; + + ht_old = rtnl_dereference(n->ht_down); + if (ht_old) + ht_old->refcnt++; + } __u32_destroy_key(new); return err; } -- 2.39.2