Unfortunately it seems that I didn't properly test the case of
an expired external querier in the recent multicast bridge series.
The setup of the timer in that case is completely broken and leads
to a NULL-pointer dereference. This patch fixes it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sending general queries was implemented as an optimisation to speed
up convergence on start-up. In order to prevent interference with
multicast routers a zero source address has to be used.
Unfortunately these packets appear to cause some multicast-aware
switches to misbehave, e.g., by disrupting multicast packets to us.
Since the multicast snooping feature still functions without sending
our own queries, this patch will change the default to not send
queries.
For those that need queries in order to speed up convergence on start-up,
a toggle is provided to restore the previous behaviour.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
As it stands when we discover that a real querier (one that queries
with a non-zero source address) we stop querying. However, even
after said querier has fallen off the edge of the earth, we will
never restart querying (unless the bridge itself is restarted).
This patch fixes this by kicking our own querier into gear when
the timer for other queriers expire.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the helper br_multicast_start_querier so that
the code which starts the queriers in br_multicast_toggle can
be reused elsewhere.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use of "unsigned int" is preferred to bare "unsigned" in net tree.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As it stands the bridge IGMP snooping system will respond to
group leave messages with queries for remaining membership.
This is both unnecessary and undesirable. First of all any
multicast routers present should be doing this rather than us.
What's more the queries that we send may end up upsetting other
multicast snooping swithces in the system that are buggy.
In fact, we can simply remove the code that send these queries
because the existing membership expiry mechanism doesn't rely
on them anyway.
So this patch simply removes all code associated with group
queries in response to group leave messages.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
otherwise source IPv6 address of ICMPV6_MGM_QUERY packet
might be random junk if IPv6 is disabled on interface or
link-local address is not yet ready (DAD).
Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of testing defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While parsing through IPv6 extension headers, fragment headers are
skipped making them invisible to the caller. This reports the
fragment offset of the last header in order to make it possible to
determine whether the packet is fragmented and, if so whether it is
a first or last fragment.
Signed-off-by: Jesse Gross <jesse@nicira.com>
C assignment can handle struct in6_addr copying.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bridge multicast snooping of ICMPv6 would incorrectly report a checksum problem
when used with Ethernet devices like sky2 that use CHECKSUM_COMPLETE.
When bytes are removed from skb, the computed checksum needs to be adjusted.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Tested-by: Martin Volf <martin.volf.42@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
multicast_lock is taken in softirq context, so we should use
spin_lock_bh() in userspace.
call-chain in softirq context:
run_timer_softirq()
br_multicast_query_expired()
call-chain in userspace:
sysfs_write_file()
store_multicast_snooping()
br_multicast_toggle()
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
br_multicast_ipv6_rcv() can call pskb_trim_rcsum() and therefore skb
head can be reallocated.
Cache icmp6_type field instead of dereferencing twice the struct
icmp6hdr pointer.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Checksum of ICMPv6 is not properly computed because the pseudo header is not used.
Thus, the MLD packet gets dropped by the bridge.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Reported-by: Ang Way Chuang <wcang@sfc.wide.ad.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bridge currently floods packets to groups that we have never
seen before to all ports. This is not required by RFC4541 and
in fact it is not desirable in environment where traffic to
unregistered group is always present.
This patch changes the behaviour so that we only send traffic
to unregistered groups to ports marked as routers.
The user can always force flooding behaviour to any given port
by marking it as a router.
Note that this change does not apply to traffic to 224.0.0.X
as traffic to those groups must always be flooded to all ports.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Upon reception of a MGM report packet the kernel sets the mrouters_only flag
in a skb that is a clone of the original skb, which means that the bridge
loses track of MGM packets (cb buffers are tied to a specific skb and not
shared) and it ends up forwading join requests to the bridge interface.
This can cause unexpected membership timeouts and intermitent/permanent loss
of connectivity as described in RFC 4541 [2.1.1. IGMP Forwarding Rules]:
A snooping switch should forward IGMP Membership Reports only to
those ports where multicast routers are attached.
[...]
Sending membership reports to other hosts can result, for IGMPv1
and IGMPv2, in unintentionally preventing a host from joining a
specific multicast group.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>
Upon reception of a IGMP/IGMPv2 membership report the kernel sets the
mrouters_only flag in a skb that may be a clone of the original skb, which
means that sometimes the bridge loses track of membership report packets (cb
buffers are tied to a specific skb and not shared) and it ends up forwading
join requests to the bridge interface.
This can cause unexpected membership timeouts and intermitent/permanent loss
of connectivity as described in RFC 4541 [2.1.1. IGMP Forwarding Rules]:
A snooping switch should forward IGMP Membership Reports only to
those ports where multicast routers are attached.
[...]
Sending membership reports to other hosts can result, for IGMPv1
and IGMPv2, in unintentionally preventing a host from joining a
specific multicast group.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Tested-by: Hayato Kakuta <kakuta.hayato@oss.ntt.co.jp>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>
Add const qualifiers to structs iphdr, ipv6hdr and in6_addr pointers
where possible, to make code intention more obvious.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
"len = ntohs(ip6h->payload_len)" does not include the length of the ipv6
header itself, which the rest of this function assumes, though.
This leads to a length check less restrictive as it should be in the
following line for one thing. For another, it very likely leads to an
integer underrun when substracting the offset and therefore to a very
high new value of 'len' due to its unsignedness. This will ultimately
lead to the pskb_trim_rcsum() practically never being called, even in
the cases where it should.
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ipv6_dev_get_saddr() is currently called with an uninitialized
destination address. Although in tests it usually seemed to nevertheless
always fetch the right source address, there seems to be a possible race
condition.
Therefore this commit changes this, first setting the destination
address and only after that fetching the source address.
Reported-by: Jan Beulich <JBeulich@novell.com>
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the bridge multicast snooping feature periodically issues
IPv6 general multicast listener queries to sense the absence of a
listener.
For this, it uses :: as its source address - however RFC 2710 requires:
"To be valid, the Query message MUST come from a link-local IPv6 Source
Address". Current Linux kernel versions seem to follow this requirement
and ignore our bogus MLD queries.
With this commit a link local address from the bridge interface is being
used to issue the MLD query, resulting in other Linux devices which are
multicast listeners in the network to respond with a MLD response (which
was not the case before).
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Map the IPv6 header's destination multicast address to an ethernet
source address instead of the MLD queries multicast address.
For instance for a general MLD query (multicast address in the MLD query
set to ::), this would wrongly be mapped to 33:33:00:00:00:00, although
an MLD queries destination MAC should always be 33:33:00:00:00:01 which
matches the IPv6 header's multicast destination ff02::1.
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the multicast bridge snooping support is not active for
link local multicast. I assume this has been done to leave
important multicast data untouched, like IPv6 Neighborhood Discovery.
In larger, bridged, local networks it could however be desirable to
optimize for instance local multicast audio/video streaming too.
With the transient flag in IPv6 multicast addresses we have an easy
way to optimize such multimedia traffic without tempering with the
high priority multicast data from well-known addresses.
This patch alters the multicast bridge snooping for IPv6, to take
effect for transient multicast addresses instead of non-link-local
addresses.
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The nsrcs number is 2 Byte wide, therefore we need to call ntohs()
before using it.
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
We actually want a pointer to the grec_nsrcr and not the following
field. Otherwise we can get very high values for *nsrcs as the first two
bytes of the IPv6 multicast address are being used instead, leading to
a failing pskb_may_pull() which results in MLDv2 reports not being
parsed.
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The protocol type for IPv6 entries in the hash table for multicast
bridge snooping is falsely set to ETH_P_IP, marking it as an IPv4
address, instead of setting it to ETH_P_IPV6, which results in negative
look-ups in the hash table later.
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
As it turns out we never need to walk through the list of multicast
groups subscribed by the bridge interface itself (the only time we'd
want to do that is when we shut down the bridge, in which case we
simply walk through all multicast groups), we don't really need to
keep an hlist for mp->mglist.
This means that we can replace it with just a single bit to indicate
whether the bridge interface is subscribed to a group.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a couple of spots where we are supposed to modify the port
group timer (p->timer) we instead modify the bridge interface
group timer (mp->timer).
The effect of this is mostly harmless. However, it can cause
port subscriptions to be longer than they should be, thus making
snooping less effective.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The list mp->mglist is used to indicate whether a multicast group
is active on the bridge interface itself as opposed to one of the
constituent interfaces in the bridge.
Unfortunately the operation that adds the mp->mglist node to the
list neglected to check whether it has already been added. This
leads to list corruption in the form of nodes pointing to itself.
Normally this would be quite obvious as it would cause an infinite
loop when walking the list. However, as this list is never actually
walked (which means that we don't really need it, I'll get rid of
it in a subsequent patch), this instead is hidden until we perform
a delete operation on the affected nodes.
As the same node may now be pointed to by more than one node, the
delete operations can then cause modification of freed memory.
This was observed in practice to cause corruption in 512-byte slabs,
most commonly leading to crashes in jbd2.
Thanks to Josef Bacik for pointing me in the right direction.
Reported-by: Ian Page Hands <ihands@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes a missing ntohs() for bridge IPv6 multicast snooping.
Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
If br_multicast_new_group returns NULL, we would return 0 (no error) to
the caller of br_multicast_add_group, which is not what we want. Instead
br_multicast_new_group should return ERR_PTR(-ENOMEM) in this case.
Also propagate the error number returned by br_mdb_rehash properly.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add modern __rcu annotatations to bridge multicast table.
Use newer hlist macros to avoid direct access to hlist internals.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently you cannot disable multicast snooping while a device is
down. There is no good reason for this restriction and this patch
removes it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6_skip_exthdr() can return error code that is below zero.
'offset' is unsigned, so it makes no sense.
ipv6_skip_exthdr() returns 'int' so we can painlessly change type of
offset to int.
Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On Tue, Jul 06, 2010 at 08:48:35AM +0800, Herbert Xu wrote:
>
> bridge: Restore NULL check in br_mdb_ip_get
Resend with proper attribution.
bridge: Restore NULL check in br_mdb_ip_get
Somewhere along the line the NULL check in br_mdb_ip_get went
AWOL, causing crashes when we receive an IGMP packet with no
multicast table allocated.
This patch restores it and ensures all br_mdb_*_get functions
use it.
Reported-by: Frank Arnold <frank.arnold@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Thanks,
Signed-off-by: David S. Miller <davem@davemloft.net>
Use one set of macro's for all bridge messages.
Note: can't use netdev_XXX macro's because bridge is purely
virtual and has no device parent.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The recently introduced bridge mulitcast port group list was only
partially using RCU correctly. It was missing rcu_dereference()
and missing the necessary barrier on deletion.
The code should have used one of the standard list methods (list or hlist)
instead of open coding a RCU based link list.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
By coding slightly differently, there are only two cases
to deal with: add at head and add after previous entry.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit ff65e8275f.
As explained by Stephen Hemminger, the traversal doesn't require
RCU handling as we hold a lock.
The list addition et al. calls, on the other hand, do.
Signed-off-by: David S. Miller <davem@davemloft.net>
I prefer that the hlist be only accessed through the hlist macro
objects. Explicit twiddling of links (especially with RCU) exposes
the code to future bugs.
Compile tested only.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based upon a report from Stephen Rothwell:
--------------------
net/bridge/br_multicast.c: In function 'br_ip6_multicast_alloc_query':
net/bridge/br_multicast.c:469: error: implicit declaration of function 'csum_ipv6_magic'
Introduced by commit 08b202b672 ("bridge
br_multicast: IPv6 MLD support") from the net tree.
csum_ipv6_magic is declared in net/ip6_checksum.h ...
--------------------
Signed-off-by: David S. Miller <davem@davemloft.net>
Even with commit 32dec5dd02 ("bridge
br_multicast: Don't refer to BR_INPUT_SKB_CB(skb)->mrouters_only
without IGMP snooping."), BR_INPUT_SKB_CB(skb)->mrouters_only is
not appropriately initialized if IGMP/MLD snooping support is
compiled and disabled, so we can see garbage.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce struct br_ip{} to store ip address and protocol
and make functions more generic so that we can support
both IPv4 and IPv6 with less pain.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
