linux-stable.git/net/bridge, branch v3.16.6

bridge: Fix br_should_learn to check vlan_enabled

2014-10-15T10:05:28+00:00

[ Upstream commit c095f248e63ada504dd90c90baae673ae10ee3fe ]

As Toshiaki Makita pointed out, the BRIDGE_INPUT_SKB_CB will
not be initialized in br_should_learn() as that function
is called only from br_handle_local_finish().  That is
an input handler for link-local ethernet traffic so it perfectly
correct to check br->vlan_enabled here.

Reported-by: Toshiaki Makita
Fixes: 20adfa1 bridge: Check if vlan filtering is enabled only once.
Signed-off-by: Vladislav Yasevich 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: Check if vlan filtering is enabled only once.

2014-10-15T10:05:28+00:00

[ Upstream commit 20adfa1a81af00bf2027644507ad4fa9cd2849cf ]

The bridge code checks if vlan filtering is enabled on both
ingress and egress.   When the state flip happens, it
is possible for the bridge to currently be forwarding packets
and forwarding behavior becomes non-deterministic.  Bridge
may drop packets on some interfaces, but not others.

This patch solves this by caching the filtered state of the
packet into skb_cb on ingress.  The skb_cb is guaranteed to
not be over-written between the time packet entres bridge
forwarding path and the time it leaves it.  On egress, we
can then check the cached state to see if we need to
apply filtering information.

Signed-off-by: Vladislav Yasevich 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Always untag vlan-tagged traffic on input.

2014-10-15T10:05:26+00:00

[ Upstream commit 0d5501c1c828fb97d02af50aa9d2b1a5498b94e4 ]

Currently the functionality to untag traffic on input resides
as part of the vlan module and is build only when VLAN support
is enabled in the kernel.  When VLAN is disabled, the function
vlan_untag() turns into a stub and doesn't really untag the
packets.  This seems to create an interesting interaction
between VMs supporting checksum offloading and some network drivers.

There are some drivers that do not allow the user to change
tx-vlan-offload feature of the driver.  These drivers also seem
to assume that any VLAN-tagged traffic they transmit will
have the vlan information in the vlan_tci and not in the vlan
header already in the skb.  When transmitting skbs that already
have tagged data with partial checksum set, the checksum doesn't
appear to be updated correctly by the card thus resulting in a
failure to establish TCP connections.

The following is a packet trace taken on the receiver where a
sender is a VM with a VLAN configued.  The host VM is running on
doest not have VLAN support and the outging interface on the
host is tg3:
10:12:43.503055 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q
(0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27243,
offset 0, flags [DF], proto TCP (6), length 60)
    10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect
-> 0x48d9), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val
4294837885 ecr 0,nop,wscale 7], length 0
10:12:44.505556 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q
(0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27244,
offset 0, flags [DF], proto TCP (6), length 60)
    10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect
-> 0x44ee), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val
4294838888 ecr 0,nop,wscale 7], length 0

This connection finally times out.

I've only access to the TG3 hardware in this configuration thus have
only tested this with TG3 driver.  There are a lot of other drivers
that do not permit user changes to vlan acceleration features, and
I don't know if they all suffere from a similar issue.

The patch attempt to fix this another way.  It moves the vlan header
stipping code out of the vlan module and always builds it into the
kernel network core.  This way, even if vlan is not supported on
a virtualizatoin host, the virtual machines running on top of such
host will still work with VLANs enabled.

CC: Patrick McHardy 
CC: Nithin Nayak Sujir 
CC: Michael Chan 
CC: Jiri Pirko 
Signed-off-by: Vladislav Yasevich 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: fix compile error when compiling without IPv6 support

2014-06-12T18:00:24+00:00

Some fields in "struct net_bridge" aren't available when compiling the
kernel without IPv6 support. Therefore adding a check/macro to skip the
complaining code sections in that case.

Introduced by 2cd4143192e8c60f66cb32c3a30c76d0470a372d
("bridge: memorize and export selected IGMP/MLD querier port")

Reported-by: kbuild test robot 
Signed-off-by: Linus Lüssing 
Signed-off-by: David S. Miller

bridge: fix smatch warning / potential null pointer dereference

2014-06-12T18:00:24+00:00

"New smatch warnings:
  net/bridge/br_multicast.c:1368 br_ip6_multicast_query() error:
    we previously assumed 'group' could be null (see line 1349)"

In the rare (sort of broken) case of a query having a Maximum
Response Delay of zero, we could create a potential null pointer
dereference.

Fixing this by skipping the multicast specific MLD Query parsing again
if no multicast group address is available.

Introduced by dc4eb53a996a78bfb8ea07b47423ff5a3aadc362
("bridge: adhere to querier election mechanism specified by RFCs")

Reported-by: Dan Carpenter 
Signed-off-by: Linus Lüssing 
Signed-off-by: David S. Miller

bridge: Support 802.1ad vlan filtering

2014-06-11T22:22:53+00:00

This enables us to change the vlan protocol for vlan filtering.
We come to be able to filter frames on the basis of 802.1ad vlan tags
through a bridge.

This also changes br->group_addr if it has not been set by user.
This is needed for an 802.1ad bridge.
(See IEEE 802.1Q-2011 8.13.5.)

Furthermore, this sets br->group_fwd_mask_required so that an 802.1ad
bridge can forward the Nearest Customer Bridge group addresses except
for br->group_addr, which should be passed to higher layer.

To change the vlan protocol, write a protocol in sysfs:
# echo 0x88a8 > /sys/class/net/br0/bridge/vlan_protocol

Signed-off-by: Toshiaki Makita 
Signed-off-by: David S. Miller

bridge: Prepare for forwarding another bridge group addresses

2014-06-11T22:22:53+00:00

If a bridge is an 802.1ad bridge, it must forward another bridge group
addresses (the Nearest Customer Bridge group addresses).
(For details, see IEEE 802.1Q-2011 8.6.3.)

As user might not want group_fwd_mask to be modified by enabling 802.1ad,
introduce a new mask, group_fwd_mask_required, which indicates addresses
the bridge wants to forward. This will be set by enabling 802.1ad.

Signed-off-by: Toshiaki Makita 
Signed-off-by: David S. Miller

bridge: Prepare for 802.1ad vlan filtering support

2014-06-11T22:22:53+00:00

This enables a bridge to have vlan protocol informantion and allows vlan
tag manipulation (retrieve, insert and remove tags) according to the vlan
protocol.

Signed-off-by: Toshiaki Makita 
Signed-off-by: David S. Miller

bridge: Add 802.1ad tx vlan acceleration

2014-06-11T22:22:53+00:00

Bridge device doesn't need to embed S-tag into skb->data.

Signed-off-by: Toshiaki Makita 
Signed-off-by: David S. Miller

bridge: memorize and export selected IGMP/MLD querier port

2014-06-11T06:50:47+00:00

Adding bridge support to the batman-adv multicast optimization requires
batman-adv knowing about the existence of bridged-in IGMP/MLD queriers
to be able to reliably serve any multicast listener behind this same
bridge.

Signed-off-by: Linus Lüssing 
Signed-off-by: David S. Miller