Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760655AbZKZPW4 (ORCPT ); Thu, 26 Nov 2009 10:22:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755510AbZKZPWz (ORCPT ); Thu, 26 Nov 2009 10:22:55 -0500 Received: from moutng.kundenserver.de ([212.227.126.187]:61473 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755310AbZKZPWy (ORCPT ); Thu, 26 Nov 2009 10:22:54 -0500 From: Arnd Bergmann To: Patrick McHardy , David Miller Subject: Re: [PATCH 1/4] veth: move loopback logic to common location Date: Thu, 26 Nov 2009 16:21:27 +0100 User-Agent: KMail/1.12.2 (Linux/2.6.31-14-generic; KDE/4.3.2; x86_64; ; ) Cc: "Eric W. Biederman" , virtualization@lists.linux-foundation.org, Herbert Xu , Eric Dumazet , Anna Fischer , netdev@vger.kernel.org, bridge@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Mark Smith , Gerhard Stenzel , Jens Osterkamp , Patrick Mullaney , Stephen Hemminger References: <1259024166-28158-1-git-send-email-arnd@arndb.de> <4B0C2824.5010502@trash.net> In-Reply-To: <4B0C2824.5010502@trash.net> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Message-Id: <200911261621.28298.arnd@arndb.de> X-Provags-ID: V01U2FsdGVkX1/Uej0ynUK29XrlYgHQ1YpNOsEgpphLBPUmGqN qFAMMzcBsJZ74k4G3JbZ690l99JBKKwayuvTCRuLnzIspqzLkQ 3geC6zX0/FIn3uKHyTzuQ== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4254 Lines: 132 On Tuesday 24 November 2009, Patrick McHardy wrote: > Eric W. Biederman wrote: > > I don't quite follow what you intend with dev_queue_xmit when the macvlan > > is in one namespace and the real physical device is in another. Are > > you mentioning that the packet classifier runs in the namespace where > > the primary device lives with packets from a different namespace? > > Exactly. And I think we should make sure that the namespace of > the macvlan device can't (deliberately or accidentally) cause > misclassification. This is independent of my series and a preexisting problem, right? Which fields do you think need to be reset to maintain namespace isolation for the outbound path in macvlan? --- net: maintain namespace isolation between vlan and real device In the vlan and macvlan drivers, the start_xmit function forwards data to the dev_queue_xmit function for another device, which may potentially belong to a different namespace. To make sure that classification stays within a single namespace, this resets the potentially critical fields. Signed-off-by: Arnd Bergmann --- drivers/net/macvlan.c | 2 +- include/linux/netdevice.h | 9 +++++++++ net/8021q/vlan_dev.c | 2 +- net/core/dev.c | 26 ++++++++++++++++++++++---- 4 files changed, 33 insertions(+), 6 deletions(-) diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 322112c..edcebf1 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -269,7 +269,7 @@ static int macvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev) } xmit_world: - skb->dev = vlan->lowerdev; + skb_set_dev(skb, vlan->lowerdev); return dev_queue_xmit(skb); } diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 9428793..fdf4a1a 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1009,6 +1009,15 @@ static inline bool netdev_uses_dsa_tags(struct net_device *dev) return 0; } +#ifdef CONFIG_NET_NS +static inline void skb_set_dev(struct sk_buff *skb, struct net_device *dev) +{ + skb->dev = dev; +} +#else /* CONFIG_NET_NS */ +void skb_set_dev(struct sk_buff *skb, struct net_device *dev); +#endif + static inline bool netdev_uses_trailer_tags(struct net_device *dev) { #ifdef CONFIG_NET_DSA_TAG_TRAILER diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c index de0dc6b..51fcfff 100644 --- a/net/8021q/vlan_dev.c +++ b/net/8021q/vlan_dev.c @@ -323,7 +323,7 @@ static netdev_tx_t vlan_dev_hard_start_xmit(struct sk_buff *skb, } - skb->dev = vlan_dev_info(dev)->real_dev; + skb_set_dev(skb, vlan_dev_info(dev)->real_dev); len = skb->len; ret = dev_queue_xmit(skb); diff --git a/net/core/dev.c b/net/core/dev.c index f8baa15..7179b58 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1448,13 +1448,10 @@ int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) if (skb->len > (dev->mtu + dev->hard_header_len)) return NET_RX_DROP; - skb_dst_drop(skb); + skb_set_dev(skb, dev); skb->tstamp.tv64 = 0; skb->pkt_type = PACKET_HOST; skb->protocol = eth_type_trans(skb, dev); - skb->mark = 0; - secpath_reset(skb); - nf_reset(skb); return netif_rx(skb); } EXPORT_SYMBOL_GPL(dev_forward_skb); @@ -1614,6 +1611,27 @@ static bool dev_can_checksum(struct net_device *dev, struct sk_buff *skb) return false; } +/** + * skb_dev_set -- assign a buffer to a new device + * @skb: buffer for the new device + * @dev: network device + * + * If an skb is owned by a device already, we have to reset + * all data private to the namespace a device belongs to + * before assigning it a new device. + */ +void skb_set_dev(struct sk_buff *skb, struct net_device *dev) +{ + if (skb->dev && !net_eq(dev_net(skb->dev), dev_net(dev))) { + secpath_reset(skb); + skb_dst_drop(skb); + nf_reset(skb); + skb->mark = 0; + } + skb->dev = dev; +} +EXPORT_SYMBOL(skb_set_dev); + /* * Invalidate hardware checksum when packet is to be mangled, and * complete checksum manually on outgoing path. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/