net: Fix a data-race around netdev_unregister_timeout_secs.

While reading netdev_unregister_timeout_secs, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 5aa3afe ("net: make unregister netdev warning timeout configurable") Signed-off-by: Kuniyuki Iwashima <[email protected]> Acked-by: Dmitry Vyukov <[email protected]> Signed-off-by: David S. Miller <[email protected]>
majek · Aug 24, 2022 · 05e49cf · 05e49cf
1 parent 8db24af
commit 05e49cf
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/net/core/dev.c b/net/core/dev.c
@@ -10284,7 +10284,7 @@ static struct net_device *netdev_wait_allrefs_any(struct list_head *list)
 				return dev;
 
 		if (time_after(jiffies, warning_time +
-			       netdev_unregister_timeout_secs * HZ)) {
+			       READ_ONCE(netdev_unregister_timeout_secs) * HZ)) {
 			list_for_each_entry(dev, list, todo_list) {
 				pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
 					 dev->name, netdev_refcnt_read(dev));