From 5b5f99b186906d198f4455b3add911c87ab361fc Mon Sep 17 00:00:00 2001
From: Zhike Wang <wangzhike@jd.com>
Date: Mon, 11 Mar 2019 03:15:54 -0700
Subject: net_sched: return correct value for *notify* functions
It is confusing to directly use return value of netlink_send()/
netlink_unicast() as the return value of *notify*, as it may be not
error at all.
Example: in tc_del_tfilter(), after calling tfilter_del_notify(), it will
goto errout if (err). However, the netlink_send()/netlink_unicast() will
return positive value even for successful case. So it may not call
tcf_chain_tp_remove() and so on to clean up the resource, as a result,
resource is leaked.
It may be easier to only check the return value of tfilter_del_nofiy(),
but it is more clean to correct all related functions.
Co-developed-by: Zengmo Gao <gaozengmo@jd.com>
Signed-off-by: Zhike Wang <wangzhike@jd.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/sched/sch_api.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
(limited to 'net/sched/sch_api.c')
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index 352b46f98440..fb8f138b9776 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1824,6 +1824,7 @@ static int tclass_notify(struct net *net, struct sk_buff *oskb,
{
struct sk_buff *skb;
u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
+ int err = 0;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
@@ -1834,8 +1835,11 @@ static int tclass_notify(struct net *net, struct sk_buff *oskb,
return -EINVAL;
}
- return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
- n->nlmsg_flags & NLM_F_ECHO);
+ err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
+ n->nlmsg_flags & NLM_F_ECHO);
+ if (err > 0)
+ err = 0;
+ return err;
}
static int tclass_del_notify(struct net *net,
@@ -1866,8 +1870,11 @@ static int tclass_del_notify(struct net *net,
return err;
}
- return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
- n->nlmsg_flags & NLM_F_ECHO);
+ err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
+ n->nlmsg_flags & NLM_F_ECHO);
+ if (err > 0)
+ err = 0;
+ return err;
}
#ifdef CONFIG_NET_CLS
--
cgit v1.2.3