From: Chris Mi <chrism@mellanox.com>
Date: Thu, 14 Dec 2017 09:09:00 +0000 (+0900)
Subject: tc: fix command "tc actions del" hang issue
X-Git-Tag: v4.15.0~75
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=83cf5bc73b858608d59c3c6126a9f37e793e15dd;p=thirdparty%2Fiproute2.git

tc: fix command "tc actions del" hang issue

If command is RTM_DELACTION, a non-NULL pointer is passed to rtnl_talk().
Then flag NLM_F_ACK is not set on n->nlmsg_flags and netlink_ack() will
not be called. Command tc will wait for the reply for ever.

Fixes: 86bf43c7c2fd ("lib/libnetlink: update rtnl_talk to support malloc buff at run time")
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Chris Mi <chrism@mellanox.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---

diff --git a/tc/m_action.c b/tc/m_action.c
index 8185819db..fc4223648 100644
--- a/tc/m_action.c
+++ b/tc/m_action.c
@@ -528,7 +528,7 @@ static int tc_action_gd(int cmd, unsigned int flags,
 
 	req.n.nlmsg_seq = rth.dump = ++rth.seq;
 
-	if (rtnl_talk(&rth, &req.n, &ans) < 0) {
+	if (rtnl_talk(&rth, &req.n, cmd == RTM_DELACTION ? NULL : &ans) < 0) {
 		fprintf(stderr, "We have an error talking to the kernel\n");
 		return 1;
 	}