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>
Sparse can help us find endianness bugs, but we need to make some
cleanups to be able to more easily spot real bugs.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
grec_nsrcs is in network order, we should convert to host horder in
br_multicast_igmp3_report()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The IGMP3 report parsing is looking at the wrong address for
group records. This patch fixes it.
Reported-by: Banyeer <banyeer@yahoo.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We never actually use iph again so this assignment can be removed.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since all callers of br_mdb_ip_get need to check whether the
hash table is NULL, this patch moves the check into the function.
This fixes the two callers (query/leave handler) that didn't
check it.
Reported-by: Michael Braun <michael-dev@fami-braun.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Thanks to Paul McKenny for pointing out that it is incorrect to use
synchronize_rcu_bh to ensure that pending callbacks have completed.
Instead we should use rcu_barrier_bh.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
As Paul McKenney correctly pointed out, __br_mdb_ip_get needs
to use the RCU list walking primitive in order to work correctly
on platforms where data-dependency ordering is not guaranteed.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We dereference "port" on the lines immediately before and immediately
after the test so port should hopefully never be null here.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows the user to control the hash elasticity/max
parameters. The elasticity setting does not take effect until
the next new multicast group is added. At which point it is
checked and if after rehashing it still can't be satisfied then
snooping will be disabled.
The max setting on the other hand takes effect immediately. It
must be a power of two and cannot be set to a value less than the
current number of multicast group entries. This is the only way
to shrink the multicast hash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows the user to disable IGMP snooping completely
through a sysfs toggle. It also allows the user to reenable
snooping when it has been automatically disabled due to hash
collisions. If the collisions have not been resolved however
the system will refuse to reenable snooping.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows the user to forcibly enable/disable ports as
having multicast routers attached. A port with a multicast router
will receive all multicast traffic.
The value 0 disables it completely. The default is 1 which lets
the system automatically detect the presence of routers (currently
this is limited to picking up queries), and 2 means that the port
will always receive all multicast traffic.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the core functionality of IGMP snooping support
without actually hooking it up. So this patch should be a no-op
as far as the bridge's external behaviour is concerned.
All the new code and data is controlled by the Kconfig option
BRIDGE_IGMP_SNOOPING. A run-time toggle is also available.
The multicast switching is done using an hash table that is
lockless on the read-side through RCU. On the write-side the
new multicast_lock is used for all operations. The hash table
supports dynamic growth/rehashing.
The hash table will be rehashed if any chain length exceeds a
preset limit. If rehashing does not reduce the maximum chain
length then snooping will be disabled.
These features may be added in future (in no particular order):
* IGMPv3 source support
* Non-querier router detection
* IPv6
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
