[PATCH 4.16 35/48] net-sysfs: Fix memory leak in XPS configuration

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.16-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Alexander Duyck <alexander.h.duyck@intel.com>

[ Upstream commit 664088f8d68178809b848ca450f2797efb34e8e7 ]

This patch reorders the error cases in showing the XPS configuration so
that we hold off on memory allocation until after we have verified that we
can support XPS on a given ring.

Fixes: 184c449f91fe ("net: Add support for XPS with QoS via traffic classes")
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/core/net-sysfs.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -1214,9 +1214,6 @@ static ssize_t xps_cpus_show(struct netd
 	cpumask_var_t mask;
 	unsigned long index;
 
-	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
-		return -ENOMEM;
-
 	index = get_netdev_queue_index(queue);
 
 	if (dev->num_tc) {
@@ -1226,6 +1223,9 @@ static ssize_t xps_cpus_show(struct netd
 			return -EINVAL;
 	}
 
+	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
+		return -ENOMEM;
+
 	rcu_read_lock();
 	dev_maps = rcu_dereference(dev->xps_maps);
 	if (dev_maps) {