vlan: disable SIOCSHWTSTAMP in container

With NET_ADMIN enabled in container, a normal user could be mapped to root and is able to change the real device's rx filter via ioctl on vlan, which would affect the other ptp process on host. Fix it by disabling SIOCSHWTSTAMP in container. Fixes: a6111d3 ("vlan: Pass SIOC[SG]HWTSTAMP ioctls to real device") Signed-off-by: Hangbin Liu <[email protected]> Acked-by: Richard Cochran <[email protected]> Signed-off-by: David S. Miller <[email protected]>
ambv · May 9, 2019 · 873017a · 873017a
1 parent 6c2ea9e
commit 873017a
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
@@ -370,10 +370,12 @@ static int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 	ifrr.ifr_ifru = ifr->ifr_ifru;
 
 	switch (cmd) {
+	case SIOCSHWTSTAMP:
+		if (!net_eq(dev_net(dev), &init_net))
+			break;
 	case SIOCGMIIPHY:
 	case SIOCGMIIREG:
 	case SIOCSMIIREG:
-	case SIOCSHWTSTAMP:
 	case SIOCGHWTSTAMP:
 		if (netif_device_present(real_dev) && ops->ndo_do_ioctl)
 			err = ops->ndo_do_ioctl(real_dev, &ifrr, cmd);