Messages in this thread | | | Date | Wed, 12 Jun 2013 17:56:29 +0400 | From | Sergei Shtylyov <> | Subject | Re: [PATCH net] macvlan: don't touch promisc without passthrough |
| |
Hello.
On 12-06-2013 15:34, Michael S. Tsirkin wrote:
> commit df8ef8f3aaa6692970a436204c4429210addb23a in linux 3.5 added a way
Please also specify that commit's summary line in parens.
> to control NOPROMISC macvlan flag through netlink.
> However, with a non passthrough device we don't set promisc on open or > clear it on stop, even if NOPROMISC is off. As a result:
> If userspace clears NOPROMISC on open, then does not clear it on a > netlink command, promisc counter is not decremented on stop and there > will be no way to clear it once macvlan is detached.
> If userspace does not clear NOPROMISC on open, then sets NOPROMISC on a > netlink command, promisc counter will be decremented from 0 and overflow > to fffffffff with no way to clear promisc afterwards.
> To fix, simply ignore NOPROMISC flag in a netlink command for > non-passthrough devices, same as we do at open/stop.
> While at it - since we touch this code anyway - check > dev_set_promiscuity return code and pass it to users (though an error > here is unlikely).
> Cc: "David S. Miller" <davem@davemloft.net> > CC: Roopa Prabhu <roprabhu@cisco.com> > Cc: John Fastabend <john.r.fastabend@intel.com> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > ---
> Please review, and consider for 3.10 and -stable.
> drivers/net/macvlan.c | 19 ++++++++++++------- > 1 file changed, 12 insertions(+), 7 deletions(-)
> diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c > index 1c502bb..8812402 100644 > --- a/drivers/net/macvlan.c > +++ b/drivers/net/macvlan.c > @@ -853,18 +853,23 @@ static int macvlan_changelink(struct net_device *dev, > struct nlattr *tb[], struct nlattr *data[]) > { > struct macvlan_dev *vlan = netdev_priv(dev); > - if (data && data[IFLA_MACVLAN_MODE]) > - vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]); > + > if (data && data[IFLA_MACVLAN_FLAGS]) { > __u16 flags = nla_get_u16(data[IFLA_MACVLAN_FLAGS]); > bool promisc = (flags ^ vlan->flags) & MACVLAN_FLAG_NOPROMISC; > - > - if (promisc && (flags & MACVLAN_FLAG_NOPROMISC)) > - dev_set_promiscuity(vlan->lowerdev, -1); > - else if (promisc && !(flags & MACVLAN_FLAG_NOPROMISC)) > - dev_set_promiscuity(vlan->lowerdev, 1); > + if (vlan->port->passthru && promisc) { > + int err;
Emoty line, like you did abobe, wouldn't hurt here, after declaration.
> + if (flags & MACVLAN_FLAG_NOPROMISC) > + err = dev_set_promiscuity(vlan->lowerdev, -1); > + else > + err = dev_set_promiscuity(vlan->lowerdev, 1); > + if (err < 0) > + return err; > + }
WBR, Sergei
| |