From 05e49cfc89e4f325eebbc62d24dd122e55f94c23 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Tue, 23 Aug 2022 10:46:59 -0700 Subject: [PATCH] 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: 5aa3afe107d9 ("net: make unregister netdev warning timeout configurable") Signed-off-by: Kuniyuki Iwashima Acked-by: Dmitry Vyukov Signed-off-by: David S. Miller --- net/core/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/dev.c b/net/core/dev.c index 8221322..56c8b09 100644 --- 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)); -- 2.7.4