From: Cong Wang <xiyou.wangcong@gmail.com>
Date: Wed, 29 Aug 2018 10:15:36 -0700
Subject: net_sched: add missing tcf_lock for act_connmark
Patch-mainline: v4.20-rc1
Git-commit: 506a03aa04deed321b26153aff4e61161aefa8af
References: bsc#1109837

According to the new locking rule, we have to take tcf_lock
for both ->init() and ->dump(), as RTNL will be removed.
However, it is missing for act_connmark.

Cc: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/sched/act_connmark.c |   11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

--- a/net/sched/act_connmark.c
+++ b/net/sched/act_connmark.c
@@ -143,8 +143,10 @@ static int tcf_connmark_init(struct net
 			return -EEXIST;
 		}
 		/* replacing action and zone */
+		spin_lock_bh(&ci->tcf_lock);
 		ci->tcf_action = parm->action;
 		ci->zone = parm->zone;
+		spin_unlock_bh(&ci->tcf_lock);
 		ret = 0;
 	}
 
@@ -156,16 +158,16 @@ static inline int tcf_connmark_dump(stru
 {
 	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_connmark_info *ci = to_connmark(a);
-
 	struct tc_connmark opt = {
 		.index   = ci->tcf_index,
 		.refcnt  = refcount_read(&ci->tcf_refcnt) - ref,
 		.bindcnt = atomic_read(&ci->tcf_bindcnt) - bind,
-		.action  = ci->tcf_action,
-		.zone   = ci->zone,
 	};
 	struct tcf_t t;
 
+	spin_lock_bh(&ci->tcf_lock);
+	opt.action = ci->tcf_action;
+	opt.zone = ci->zone;
 	if (nla_put(skb, TCA_CONNMARK_PARMS, sizeof(opt), &opt))
 		goto nla_put_failure;
 
@@ -173,9 +175,12 @@ static inline int tcf_connmark_dump(stru
 	if (nla_put_64bit(skb, TCA_CONNMARK_TM, sizeof(t), &t,
 			  TCA_CONNMARK_PAD))
 		goto nla_put_failure;
+	spin_unlock_bh(&ci->tcf_lock);
 
 	return skb->len;
+
 nla_put_failure:
+	spin_unlock_bh(&ci->tcf_lock);
 	nlmsg_trim(skb, b);
 	return -1;
 }