summaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorAntoine Tenart <atenart@kernel.org>2020-12-23 22:23:23 +0100
committerJakub Kicinski <kuba@kernel.org>2020-12-28 13:26:46 -0800
commit4ae2bb81649dc03dfc95875f02126b14b773f7ab (patch)
tree5894ca9c9d9f474c897e198b9429bf2abc947bc9 /net
parent2d57b4f142e0b03e854612b8e28978935414bced (diff)
net-sysfs: take the rtnl lock when accessing xps_rxqs_map and num_tc
Accesses to dev->xps_rxqs_map (when using dev->num_tc) should be protected by the rtnl lock, like we do for netif_set_xps_queue. I didn't see an actual bug being triggered, but let's be safe here and take the rtnl lock while accessing the map in sysfs. Fixes: 8af2c06ff4b1 ("net-sysfs: Add interface for Rx queue(s) map per Tx queue") Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
-rw-r--r--net/core/net-sysfs.c23
1 files changed, 18 insertions, 5 deletions
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 62ca2f2c0ee6..daf502c13d6d 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -1429,22 +1429,29 @@ static struct netdev_queue_attribute xps_cpus_attribute __ro_after_init
static ssize_t xps_rxqs_show(struct netdev_queue *queue, char *buf)
{
+ int j, len, ret, num_tc = 1, tc = 0;
struct net_device *dev = queue->dev;
struct xps_dev_maps *dev_maps;
unsigned long *mask, index;
- int j, len, num_tc = 1, tc = 0;
index = get_netdev_queue_index(queue);
+ if (!rtnl_trylock())
+ return restart_syscall();
+
if (dev->num_tc) {
num_tc = dev->num_tc;
tc = netdev_txq_to_tc(dev, index);
- if (tc < 0)
- return -EINVAL;
+ if (tc < 0) {
+ ret = -EINVAL;
+ goto err_rtnl_unlock;
+ }
}
mask = bitmap_zalloc(dev->num_rx_queues, GFP_KERNEL);
- if (!mask)
- return -ENOMEM;
+ if (!mask) {
+ ret = -ENOMEM;
+ goto err_rtnl_unlock;
+ }
rcu_read_lock();
dev_maps = rcu_dereference(dev->xps_rxqs_map);
@@ -1470,10 +1477,16 @@ static ssize_t xps_rxqs_show(struct netdev_queue *queue, char *buf)
out_no_maps:
rcu_read_unlock();
+ rtnl_unlock();
+
len = bitmap_print_to_pagebuf(false, buf, mask, dev->num_rx_queues);
bitmap_free(mask);
return len < PAGE_SIZE ? len : -EINVAL;
+
+err_rtnl_unlock:
+ rtnl_unlock();
+ return ret;
}
static ssize_t xps_rxqs_store(struct netdev_queue *queue, const char *buf,