| Message ID | 1508160032-21689-1-git-send-email-mgamal@redhat.com |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | xen-netfront, xen-netback: Use correct minimum MTU values | expand |
On Mon, Oct 16, 2017 at 03:20:32PM +0200, Mohammed Gamal wrote: > RFC791 specifies the minimum MTU to be 68, while xen-net{front|back} > drivers use a minimum value of 0. > > When set MTU to 0~67 with xen_net{front|back} driver, the network > will become unreachable immediately, the guest can no longer be pinged. > > xen_net{front|back} should not allow the user to set this value which causes > network problems. > > Reported-by: Chen Shi <cheshi@redhat.com> > Signed-off-by: Mohammed Gamal <mgamal@redhat.com> > --- > drivers/net/xen-netback/interface.c | 2 +- > drivers/net/xen-netfront.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c > index ee8ed9da..4491ca5 100644 > --- a/drivers/net/xen-netback/interface.c > +++ b/drivers/net/xen-netback/interface.c > @@ -486,7 +486,7 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, > > dev->tx_queue_len = XENVIF_QUEUE_LENGTH; > > - dev->min_mtu = 0; > + dev->min_mtu = ETH_MIN_MTU; > dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN; > > /* > diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c > index 523387e..8b8689c 100644 > --- a/drivers/net/xen-netfront.c > +++ b/drivers/net/xen-netfront.c > @@ -1316,7 +1316,7 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev) > netdev->features |= netdev->hw_features; > > netdev->ethtool_ops = &xennet_ethtool_ops; > - netdev->min_mtu = 0; > + netdev->min_mtu = ETH_MIN_MTU; > netdev->max_mtu = XEN_NETIF_MAX_TX_SIZE; > SET_NETDEV_DEV(netdev, &dev->dev); > > -- > 1.8.3.1 > Acked-by: Eduardo Otubo <otubo@redhat.com>
On Mon, Oct 16, 2017 at 03:20:32PM +0200, Mohammed Gamal wrote: > RFC791 specifies the minimum MTU to be 68, while xen-net{front|back} > drivers use a minimum value of 0. > > When set MTU to 0~67 with xen_net{front|back} driver, the network > will become unreachable immediately, the guest can no longer be pinged. > > xen_net{front|back} should not allow the user to set this value which causes > network problems. > > Reported-by: Chen Shi <cheshi@redhat.com> > Signed-off-by: Mohammed Gamal <mgamal@redhat.com> Acked-by: Wei Liu <wei.liu2@citrix.com> CC netfront maintainers
On 10/16/2017 11:05 AM, Wei Liu wrote: > On Mon, Oct 16, 2017 at 03:20:32PM +0200, Mohammed Gamal wrote: >> RFC791 specifies the minimum MTU to be 68, while xen-net{front|back} >> drivers use a minimum value of 0. >> >> When set MTU to 0~67 with xen_net{front|back} driver, the network >> will become unreachable immediately, the guest can no longer be pinged. >> >> xen_net{front|back} should not allow the user to set this value which causes >> network problems. >> >> Reported-by: Chen Shi <cheshi@redhat.com> >> Signed-off-by: Mohammed Gamal <mgamal@redhat.com> > Acked-by: Wei Liu <wei.liu2@citrix.com> > > CC netfront maintainers Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> I can take it via Xen tree unless there are objections. -boris
From: Boris Ostrovsky <boris.ostrovsky@oracle.com> Date: Mon, 16 Oct 2017 16:19:07 -0400 > On 10/16/2017 11:05 AM, Wei Liu wrote: >> On Mon, Oct 16, 2017 at 03:20:32PM +0200, Mohammed Gamal wrote: >>> RFC791 specifies the minimum MTU to be 68, while xen-net{front|back} >>> drivers use a minimum value of 0. >>> >>> When set MTU to 0~67 with xen_net{front|back} driver, the network >>> will become unreachable immediately, the guest can no longer be pinged. >>> >>> xen_net{front|back} should not allow the user to set this value which causes >>> network problems. >>> >>> Reported-by: Chen Shi <cheshi@redhat.com> >>> Signed-off-by: Mohammed Gamal <mgamal@redhat.com> >> Acked-by: Wei Liu <wei.liu2@citrix.com> >> >> CC netfront maintainers > > > Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> > > I can take it via Xen tree unless there are objections. No problem on my end.
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index ee8ed9da..4491ca5 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -486,7 +486,7 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, dev->tx_queue_len = XENVIF_QUEUE_LENGTH; - dev->min_mtu = 0; + dev->min_mtu = ETH_MIN_MTU; dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN; /* diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 523387e..8b8689c 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1316,7 +1316,7 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev) netdev->features |= netdev->hw_features; netdev->ethtool_ops = &xennet_ethtool_ops; - netdev->min_mtu = 0; + netdev->min_mtu = ETH_MIN_MTU; netdev->max_mtu = XEN_NETIF_MAX_TX_SIZE; SET_NETDEV_DEV(netdev, &dev->dev);
RFC791 specifies the minimum MTU to be 68, while xen-net{front|back} drivers use a minimum value of 0. When set MTU to 0~67 with xen_net{front|back} driver, the network will become unreachable immediately, the guest can no longer be pinged. xen_net{front|back} should not allow the user to set this value which causes network problems. Reported-by: Chen Shi <cheshi@redhat.com> Signed-off-by: Mohammed Gamal <mgamal@redhat.com> --- drivers/net/xen-netback/interface.c | 2 +- drivers/net/xen-netfront.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)