From 0a9e18d65228376c332d7ec0f87a19b8042e8a43 Mon Sep 17 00:00:00 2001
From: Phil Sutter <psutter@redhat.com>
Date: Thu, 25 Oct 2018 12:24:30 +0200
Subject: [PATCH] libnetlink: don't return error on success

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1602555
Upstream Status: iproute2.git commit b45e300024bb0

commit b45e300024bb0936a41821ad75117dc08b65669f
Author: Stephen Hemminger <stephen@networkplumber.org>
Date:   Tue Sep 25 10:08:48 2018 +0200

    libnetlink: don't return error on success

    Change to error handling broke normal code.

    Fixes: c60389e4f9ea ("libnetlink: fix leak and using unused memory on error")
    Reported-by: David Ahern <dsahern@gmail.com>
    Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/libnetlink.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/lib/libnetlink.c b/lib/libnetlink.c
index 5868092..f18dcea 100644
--- a/lib/libnetlink.c
+++ b/lib/libnetlink.c
@@ -666,17 +666,20 @@ static int __rtnl_talk_iov(struct rtnl_handle *rtnl, struct iovec *iov,
 				if (!err->error)
 					/* check messages from kernel */
 					nl_dump_ext_ack(h, errfn);
+				else {
+					errno = -err->error;
 
-				if (rtnl->proto != NETLINK_SOCK_DIAG &&
-				    show_rtnl_err)
-					rtnl_talk_error(h, err, errfn);
+					if (rtnl->proto != NETLINK_SOCK_DIAG &&
+					    show_rtnl_err)
+						rtnl_talk_error(h, err, errfn);
+				}
 
-				errno = -err->error;
 				if (answer)
 					*answer = (struct nlmsghdr *)buf;
 				else
 					free(buf);
-				return -i;
+
+				return err->error ? -i : 0;
 			}
 
 			if (answer) {
-- 
1.8.3.1