From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755961Ab3FLN4h (ORCPT ); Wed, 12 Jun 2013 09:56:37 -0400 Received: from mail-lb0-f175.google.com ([209.85.217.175]:34868 "EHLO mail-lb0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753181Ab3FLN4f (ORCPT ); Wed, 12 Jun 2013 09:56:35 -0400 Message-ID: <51B87E0D.8040009@cogentembedded.com> Date: Wed, 12 Jun 2013 17:56:29 +0400 From: Sergei Shtylyov User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 MIME-Version: 1.0 To: "Michael S. Tsirkin" CC: linux-kernel@vger.kernel.org, "David S. Miller" , Roopa Prabhu , John Fastabend , Patrick McHardy , netdev@vger.kernel.org Subject: Re: [PATCH net] macvlan: don't touch promisc without passthrough References: <1371035949-29471-1-git-send-email-mst@redhat.com> In-Reply-To: <1371035949-29471-1-git-send-email-mst@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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" > CC: Roopa Prabhu > Cc: John Fastabend > Signed-off-by: Michael S. Tsirkin > --- > 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