From ff25276de997f41197ebab91935627c249a30fc4 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Fri, 10 Aug 2018 20:51:45 +0300 Subject: [PATCH] net: sched: act_ipt: remove dependency on rtnl lock Use tcf spinlock to protect ipt action private data from concurrent modification during dump. Ipt init already takes tcf spinlock when modifying ipt state. Signed-off-by: Vlad Buslov Signed-off-by: David S. Miller --- net/sched/act_ipt.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c index 0dc787a57798..e149f0e66cb6 100644 --- a/net/sched/act_ipt.c +++ b/net/sched/act_ipt.c @@ -288,6 +288,7 @@ static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, * for foolproof you need to not assume this */ + spin_lock_bh(&ipt->tcf_lock); t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC); if (unlikely(!t)) goto nla_put_failure; @@ -307,10 +308,12 @@ static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, if (nla_put_64bit(skb, TCA_IPT_TM, sizeof(tm), &tm, TCA_IPT_PAD)) goto nla_put_failure; + spin_unlock_bh(&ipt->tcf_lock); kfree(t); return skb->len; nla_put_failure: + spin_unlock_bh(&ipt->tcf_lock); nlmsg_trim(skb, b); kfree(t); return -1; -- 2.30.2