From: Michael Braun <michael-dev@fami-braun.de>
bridge: Fix br_forward crash in promiscuous mode
It's a linux-next kernel from 2010-03-12 on an x86 system and it
OOPs in the bridge module in br_pass_frame_up (called by
br_handle_frame_finish) because brdev cannot be dereferenced (its set to
a non-null value).
Adding some BUG_ON statements revealed that
BR_INPUT_SKB_CB(skb)->brdev == br-dev
(as set in br_handle_frame_finish first)
only holds until br_forward is called.
The next call to br_pass_frame_up then fails.
Digging deeper it seems that br_forward either frees the skb or passes
it to NF_HOOK which will in turn take care of freeing the skb. The
same is holds for br_pass_frame_ip. So it seems as if two independent
skb allocations are required. As far as I can see, commit
b33084be19 ("bridge: Avoid unnecessary
clone on forward path") removed skb duplication and so likely causes
this crash. This crash does not happen on 2.6.33.
I've therefore modified br_forward the same way br_flood has been
modified so that the skb is not freed if skb0 is going to be used
and I can confirm that the attached patch resolves the issue for me.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch finally hooks up the multicast snooping module to the
data path. In particular, all multicast packets passing through
the bridge are fed into the module and switched by it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the packet is delivered to the local bridge device we may
end up cloning it unnecessarily if no bridge port can receive
the packet in br_flood.
This patch avoids this by moving the skb_clone into br_flood.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows tail-call on the call to br_pass_frame_up
in br_handle_frame_finish. This is now possible because of the
previous patch to call br_pass_frame_up last.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
At the moment we deliver to the local bridge port via the function
br_pass_frame_up before all other ports. There is no requirement
for this.
For the purpose of IGMP snooping, it would be more convenient if
we did the local port last. Therefore this patch rearranges the
bridge input processing so that the local bridge port gets to see
the packet last (if at all).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the bridge catches all STP packets; even if STP is turned
off. This prevents other systems (which do have STP turned on)
from being able to detect loops in the network.
With this patch, if STP is off, then any packet sent to the STP
multicast group address is forwarded to all ports.
Based on earlier patch by Joakim Tjernlund with changes
to go through forwarding (not local chain), and optimization
that only last octet needs to be checked.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Any frame addressed to link-local addresses should be processed by local
receive path. The earlier code would process them only if STP was enabled.
Since there are other frames like LACP for bonding, we should always
process them.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes CVS keywords that weren't updated for a long time
from comments.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Even though bridges require 6 fields from struct net_device_stats,
the on-device stats are always there, so we may just use them.
The br_dev_get_stats is no longer required after this.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This hook is protected with the RCU, so simple
if (br_should_route_hook)
br_should_route_hook(...)
is not enough on some architectures.
Use the rcu_dereference/rcu_assign_pointer in this case.
Fixed Stephen's comment concerning using the typeof().
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
With all the users of the double pointers removed, this patch mops up by
finally replacing all occurances of sk_buff ** in the netfilter API by
sk_buff *.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Due to the special location of the bridging hook, it should never see a
shared packet anyway (certainly not with any in-kernel code). So it
makes sense to unshare the skb there if necessary as that will greatly
simplify the code below it (in particular, netfilter).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The clone argument is only used by one caller and that caller can clone
the packet itself. This patch moves the clone call into the caller and
kills the clone argument.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes some packet leakage in bridge. The bridging code was
allowing forward table entries to be generated even if a device was
being blocked. The fix is to not add forwarding database entries
unless the port is active.
The bug arose as part of the conversion to processing STP frames
through normal receive path (in 2.6.17).
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Acked-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If a bridge is not running STP, then it has no way to detect a cycle
in the network. But if it is not running STP and some other machine
or device is running STP, then if STP BPDU's get forwarded to it can
detect the cycle.
This is how the old 2.4 and early 2.6 code worked.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pause frames should never make it out of the network device into
the stack. But if a device was misconfigured, it might happen.
So drop pause frames in bridge.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The change to forward STP bpdu's (for usermode STP) through normal path,
changed the packet type in the process. Since link local stuff is multicast, it
should stay pkt_type = PACKET_MULTICAST. The code was probably copy/pasted
incorrectly from the bridge pseudo-device receive path.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
While in the STP learning state, don't route packets; wait until
forwarding delay has expired. The purpose of the forwarding delay
is to detect loops in the network, and if a brouter started up
and started forwarding, it could cause a flood.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Change the bridging hook to be simple function with return value
rather than modifying the skb argument. This could generate better
code and is cleaner.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Use logic operations rather than memcmp() to compare destination
address with link local multicast addresses.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It makes sense to add this simple statistic to keep track of received
multicast packets.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This change allows link local packets (like 802.3ad and Spanning Tree
Protocol) to be processed even when the bridge is not using the port.
It fixes the chicken-egg problem for bridging a bonded device, and
may also fix problems with spanning tree failover.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bridge's communicate with each other using Spanning Tree Protocol
over a standard multicast address. There are times when testing or
layering bridges over existing topologies or tunnels, when it is
useful to use alternative multicast addresses for STP packets.
The 802.1d standard has some unused addresses, that can be used for this.
This patch is restrictive in that it only allows one of the possible
addresses in the standard.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use LLC for the receive path of Spanning Tree Protocol packets.
This allows link local multicast packets to be received by
other protocols (if they care), and uses the existing LLC
code to get STP packets back into bridge code.
The bridge multicast address is also checked, so bridges using
other link local multicast addresses are ignored. This allows
for use of different multicast addresses to define separate STP
domains.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The netfilter hook that is used to receive frames doesn't need to be a
stub. It is only called in two ways, both of which ignore the return
value.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change Bridge receive path to correctly handle RCU removal of device
from bridge. Also fixes deadlock between carrier_check and del_nbp.
This replaces the previous deleted flag fix.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This uses is_multicast_ether_addr() because it has recently been
changed to do the same thing these seperate tests are doing.
Signed-off-by: Kris Katterjohn <kjak@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
While in the learning state, run filters but drop the result.
This prevents us from acquiring bad fdb entries in learning state.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use compare_ether_addr in bridge code.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This improves the bridge local receive path by avoiding going
through another softirq. The bridge receive path is already being called
from a netif_receive_skb() there is no point in going through another
receiveq round trip.
Recursion is limited because bridge can never be a port of a bridge
so handle_bridge() always returns.
Signed-off-by: David S. Miller <davem@davemloft.net>
Avoid poisoning of the bridge forwarding table by frames that have been
dropped by filtering. This prevents spoofed source addresses on hostile
side of bridge from causing packet leakage, a small but possible security
risk.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
