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However, the subsequent call to put_ifaddrmsg() uses ifa->flags again instead of the already read local variable. This re-read is unnecessary because no other thread can modify ifa->flags between the initial READ_ONCE() and the subsequent use in put_ifaddrmsg(). Signed-off-by: Zilin Guan --- net/ipv6/addrconf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 94dceac52884..c4b080471b39 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -5143,7 +5143,7 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, return -EMSGSIZE; =20 flags =3D READ_ONCE(ifa->flags); - put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope), + put_ifaddrmsg(nlh, ifa->prefix_len, flags, rt_scope(ifa->scope), ifa->idev->dev->ifindex); =20 if (args->netnsid >=3D 0 && --=20 2.34.1