diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index d961e6c2d09d..480c906cb374 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1582,8 +1582,8 @@ skip_routeinfo:
 		memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
 		mtu = ntohl(n);
 
-		if (in6_dev->ra_mtu != mtu) {
-			in6_dev->ra_mtu = mtu;
+		if (READ_ONCE(in6_dev->ra_mtu) != mtu) {
+			WRITE_ONCE(in6_dev->ra_mtu, mtu);
 			send_ifinfo_notify = true;
 		}