From 2e9526b352061ee0fd2a1580a2e3a5af960dabc4 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Fri, 30 Oct 2009 05:51:48 +0000 Subject: [PATCH] gre: Fix dev_addr clobbering for gretap Nathan Neulinger noticed that gretap devices get their MAC address from the local IP address, which results in invalid MAC addresses half of the time. This is because gretap is still using the tunnel netdev ops rather than the correct tap netdev ops struct. This patch also fixes changelink to not clobber the MAC address for the gretap case. Signed-off-by: Herbert Xu Acked-by: Stephen Hemminger Tested-by: Nathan Neulinger Signed-off-by: David S. Miller --- net/ipv4/ip_gre.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 41ada9904d3..14333385262 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -1464,7 +1464,7 @@ static void ipgre_tap_setup(struct net_device *dev) ether_setup(dev); - dev->netdev_ops = &ipgre_netdev_ops; + dev->netdev_ops = &ipgre_tap_netdev_ops; dev->destructor = free_netdev; dev->iflink = 0; @@ -1525,25 +1525,29 @@ static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[], if (t->dev != dev) return -EEXIST; } else { - unsigned nflags = 0; - t = nt; - if (ipv4_is_multicast(p.iph.daddr)) - nflags = IFF_BROADCAST; - else if (p.iph.daddr) - nflags = IFF_POINTOPOINT; + if (dev->type != ARPHRD_ETHER) { + unsigned nflags = 0; - if ((dev->flags ^ nflags) & - (IFF_POINTOPOINT | IFF_BROADCAST)) - return -EINVAL; + if (ipv4_is_multicast(p.iph.daddr)) + nflags = IFF_BROADCAST; + else if (p.iph.daddr) + nflags = IFF_POINTOPOINT; + + if ((dev->flags ^ nflags) & + (IFF_POINTOPOINT | IFF_BROADCAST)) + return -EINVAL; + } ipgre_tunnel_unlink(ign, t); t->parms.iph.saddr = p.iph.saddr; t->parms.iph.daddr = p.iph.daddr; t->parms.i_key = p.i_key; - memcpy(dev->dev_addr, &p.iph.saddr, 4); - memcpy(dev->broadcast, &p.iph.daddr, 4); + if (dev->type != ARPHRD_ETHER) { + memcpy(dev->dev_addr, &p.iph.saddr, 4); + memcpy(dev->broadcast, &p.iph.daddr, 4); + } ipgre_tunnel_link(ign, t); netdev_state_change(dev); } -- 2.39.3