bridge: Fix the way to check if a local fdb entry can be deleted

We should take into account the followings when deleting a local fdb
entry.

- nbp_vlan_find() can be used only when vid != 0 to chec

bridge: Fix the way to check if a local fdb entry can be deleted

We should take into account the followings when deleting a local fdb
entry.

- nbp_vlan_find() can be used only when vid != 0 to check if an entry is
deletable, because a fdb entry with vid 0 can exist at any time while
nbp_vlan_find() always return false with vid 0.

Example of problematic case:
ip link set eth0 address 12:34:56:78:90:ab
ip link set eth1 address 12:34:56:78:90:ab
brctl addif br0 eth0
brctl addif br0 eth1
ip link set eth0 address aa:bb:cc:dd:ee:ff
Then, the fdb entry 12:34:56:78:90:ab will be deleted even though the
bridge port eth1 still has that address.

- The port to which the bridge device is attached might needs a local entry
if its mac address is set manually.

Example of problematic case:
ip link set eth0 address 12:34:56:78:90:ab
brctl addif br0 eth0
ip link set br0 address 12:34:56:78:90:ab
ip link set eth0 address aa:bb:cc:dd:ee:ff
Then, the fdb still must have the entry 12:34:56:78:90:ab, but it will be
deleted.

We can use br->dev->addr_assign_type to check if the address is manually
set or not, but I propose another approach.

Since we delete and insert local entries whenever changing mac address
of the bridge device, we can change dst of the entry to NULL regardless of
addr_assign_type when deleting an entry associated with a certain port,
and if it is found to be unnecessary later, then delete it.
That is, if changing mac address of a port, the entry might be changed
to its dst being NULL first, but is eventually deleted when recalculating
and changing bridge id.

This approach is especially useful when we want to share the code with
deleting vlan in which the bridge device might want such an entry regardless
of addr_assign_type, and makes things easy because we don't have to consider
if mac address of the bridge device will be changed or not at the time we
delete a local entry of a port, which means fdb code will not be bothered
even if the bridge id calculating logic is changed in the future.

Also, this change reduces inconsistent state, where frames whose dst is the
mac address of the bridge, can't reach the bridge because of premature fdb
entry deletion. This change reduces the possibility that the bridge device
replies unreachable mac address to arp requests, which could occur during
the short window between calling del_nbp() and br_stp_recalculate_bridge_id()
in br_del_if(). This will effective after br_fdb_delete_by_port() starts to
use the same code by following patch.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: Fix the way to find old local fdb entries in br_fdb_changeaddr

br_fdb_changeaddr() assumes that there is at most one local entry per port
per vlan. It used to be true, but since commit 36fd2

bridge: Fix the way to find old local fdb entries in br_fdb_changeaddr

br_fdb_changeaddr() assumes that there is at most one local entry per port
per vlan. It used to be true, but since commit 36fd2b63e3b4 ("bridge: allow
creating/deleting fdb entries via netlink"), it has not been so.
Therefore, the function might fail to search a correct previous address
to be deleted and delete an arbitrary local entry if user has added local
entries manually.

Example of problematic case:
ip link set eth0 address ee:ff:12:34:56:78
brctl addif br0 eth0
bridge fdb add 12:34:56:78:90:ab dev eth0 master
ip link set eth0 address aa:bb:cc:dd:ee:ff
Then, the address 12:34:56:78:90:ab might be deleted instead of
ee:ff:12:34:56:78, the original mac address of eth0.

Address this issue by introducing a new flag, added_by_user, to struct
net_bridge_fdb_entry.

Note that br_fdb_delete_by_port() has to set added_by_user to 0 in cases
like:
ip link set eth0 address 12:34:56:78:90:ab
ip link set eth1 address aa:bb:cc:dd:ee:ff
brctl addif br0 eth0
bridge fdb add aa:bb:cc:dd:ee:ff dev eth0 master
brctl addif br0 eth1
brctl delif br0 eth0
In this case, kernel should delete the user-added entry aa:bb:cc:dd:ee:ff,
but it also should have been added by "brctl addif br0 eth1" originally,
so we don't delete it and treat it a new kernel-created entry.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

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bridge: move br_net_exit() to br.c

And it can become static.

Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gm

bridge: move br_net_exit() to br.c

And it can become static.

Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: unify the pcpu_tstats and br_cpu_netstats as one

They are same, so unify them as one, pcpu_sw_netstats.

Define pcpu_sw_netstat in netdevice.h, remove pcpu_tstats
from if_tunnel and remove br_c

net: unify the pcpu_tstats and br_cpu_netstats as one

They are same, so unify them as one, pcpu_sw_netstats.

Define pcpu_sw_netstat in netdevice.h, remove pcpu_tstats
from if_tunnel and remove br_cpu_netstats from br_private.h

Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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bridge: add space before '(/{', after ',', etc.

Spaces required before the open parenthesis '(', before the open
brace '{', after that ',' and around that '?/:'.

Signed-off-by: Tan Xiaojun <tanxiao

bridge: add space before '(/{', after ',', etc.

Spaces required before the open parenthesis '(', before the open
brace '{', after that ',' and around that '?/:'.

Signed-off-by: Tan Xiaojun <tanxiaojun@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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br: fix use of ->rx_handler_data in code executed on non-rx_handler path

br_stp_rcv() is reached by non-rx_handler path. That means there is no
guarantee that dev is bridge port and therefore simple

br: fix use of ->rx_handler_data in code executed on non-rx_handler path

br_stp_rcv() is reached by non-rx_handler path. That means there is no
guarantee that dev is bridge port and therefore simple NULL check of
->rx_handler_data is not enough. There is need to check if dev is really
bridge port and since only rcu read lock is held here, do it by checking
->rx_handler pointer.

Note that synchronize_net() in netdev_rx_handler_unregister() ensures
this approach as valid.

Introduced originally by:
commit f350a0a87374418635689471606454abc7beaa3a
"bridge: use rx_handler_data pointer to store net_bridge_port pointer"

Fixed but not in the best way by:
commit b5ed54e94d324f17c97852296d61a143f01b227a
"bridge: fix RCU races with bridge port"

Reintroduced by:
commit 716ec052d2280d511e10e90ad54a86f5b5d4dcc2
"bridge: fix NULL pointer deref of br_port_get_rcu"

Please apply to stable trees as well. Thanks.

RH bugzilla reference: https://bugzilla.redhat.com/show_bug.cgi?id=1025770

Reported-by: Laine Stump <laine@redhat.com>
Debugged-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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bridge: pass correct vlan id to multicast code

Currently multicast code attempts to extrace the vlan id from
the skb even when vlan filtering is disabled. This can lead
to mdb entries being created

bridge: pass correct vlan id to multicast code

Currently multicast code attempts to extrace the vlan id from
the skb even when vlan filtering is disabled. This can lead
to mdb entries being created with the wrong vlan id.
Pass the already extracted vlan id to the multicast
filtering code to make the correct id is used in
creation as well as lookup.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Acked-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

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Revert "bridge: only expire the mdb entry when query is received"

While this commit was a good attempt to fix issues occuring when no
multicast querier is present, this commit still has two more iss

Revert "bridge: only expire the mdb entry when query is received"

While this commit was a good attempt to fix issues occuring when no
multicast querier is present, this commit still has two more issues:

1) There are cases where mdb entries do not expire even if there is a
querier present. The bridge will unnecessarily continue flooding
multicast packets on the according ports.

2) Never removing an mdb entry could be exploited for a Denial of
Service by an attacker on the local link, slowly, but steadily eating up
all memory.

Actually, this commit became obsolete with
"bridge: disable snooping if there is no querier" (b00589af3b)
which included fixes for a few more cases.

Therefore reverting the following commits (the commit stated in the
commit message plus three of its follow up fixes):

====================
Revert "bridge: update mdb expiration timer upon reports."
This reverts commit f144febd93d5ee534fdf23505ab091b2b9088edc.
Revert "bridge: do not call setup_timer() multiple times"
This reverts commit 1faabf2aab1fdaa1ace4e8c829d1b9cf7bfec2f1.
Revert "bridge: fix some kernel warning in multicast timer"
This reverts commit c7e8e8a8f7a70b343ca1e0f90a31e35ab2d16de1.
Revert "bridge: only expire the mdb entry when query is received"
This reverts commit 9f00b2e7cf241fa389733d41b615efdaa2cb0f5b.
====================

CC: Cong Wang <amwang@redhat.com>
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Reviewed-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: 8021q/bluetooth/bridge/can/ceph: Remove extern from function prototypes

There are a mix of function prototypes with and without extern
in the kernel sources. Standardize on not using extern fo

net: 8021q/bluetooth/bridge/can/ceph: Remove extern from function prototypes

There are a mix of function prototypes with and without extern
in the kernel sources. Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler. Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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bridge: Fix the way the PVID is referenced

We are using the VLAN_TAG_PRESENT bit to detect whether the PVID is
set or not at br_get_pvid(), while we don't care about the bit in
adding/deleting the P

bridge: Fix the way the PVID is referenced

We are using the VLAN_TAG_PRESENT bit to detect whether the PVID is
set or not at br_get_pvid(), while we don't care about the bit in
adding/deleting the PVID, which makes it impossible to forward any
incomming untagged frame with vlan_filtering enabled.

Since vid 0 cannot be used for the PVID, we can use vid 0 to indicate
that the PVID is not set, which is slightly more efficient than using
the VLAN_TAG_PRESENT.

Fix the problem by getting rid of using the VLAN_TAG_PRESENT.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Reviewed-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: fix NULL pointer deref of br_port_get_rcu

The NULL deref happens when br_handle_frame is called between these
2 lines of del_nbp:
dev->priv_flags &= ~IFF_BRIDGE_PORT;
/* --> br_handle_fram

bridge: fix NULL pointer deref of br_port_get_rcu

The NULL deref happens when br_handle_frame is called between these
2 lines of del_nbp:
dev->priv_flags &= ~IFF_BRIDGE_PORT;
/* --> br_handle_frame is called at this time */
netdev_rx_handler_unregister(dev);

In br_handle_frame the return of br_port_get_rcu(dev) is dereferenced
without check but br_port_get_rcu(dev) returns NULL if:
!(dev->priv_flags & IFF_BRIDGE_PORT)

Eric Dumazet pointed out the testing of IFF_BRIDGE_PORT is not necessary
here since we're in rcu_read_lock and we have synchronize_net() in
netdev_rx_handler_unregister. So remove the testing of IFF_BRIDGE_PORT
and by the previous patch, make sure br_port_get_rcu is called in
bridging code.

Signed-off-by: Hong Zhiguo <zhiguohong@tencent.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: use br_port_get_rtnl within rtnl lock

current br_port_get_rcu is problematic in bridging path
(NULL deref). Change these calls in netlink path first.

Signed-off-by: Hong Zhiguo <zhiguohong@

bridge: use br_port_get_rtnl within rtnl lock

current br_port_get_rcu is problematic in bridging path
(NULL deref). Change these calls in netlink path first.

Signed-off-by: Hong Zhiguo <zhiguohong@tencent.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: Clamp forward_delay when enabling STP

At some point limits were added to forward_delay. However, the
limits are only enforced when STP is enabled. This created a
scenario where you could h

bridge: Clamp forward_delay when enabling STP

At some point limits were added to forward_delay. However, the
limits are only enforced when STP is enabled. This created a
scenario where you could have a value outside the allowed range
while STP is disabled, which then stuck around even after STP
is enabled.

This patch fixes this by clamping the value when we enable STP.

I had to move the locking around a bit to ensure that there is
no window where someone could insert a value outside the range
while we're in the middle of enabling STP.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Cheers,
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: apply multicast snooping to IPv6 link-local, too

The multicast snooping code should have matured enough to be safely
applicable to IPv6 link-local multicast addresses (excluding the
link-loc

bridge: apply multicast snooping to IPv6 link-local, too

The multicast snooping code should have matured enough to be safely
applicable to IPv6 link-local multicast addresses (excluding the
link-local all nodes address, ff02::1), too.

Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

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bridge: separate querier and query timer into IGMP/IPv4 and MLD/IPv6 ones

Currently we would still potentially suffer multicast packet loss if there
is just either an IGMP or an MLD querier: For the

bridge: separate querier and query timer into IGMP/IPv4 and MLD/IPv6 ones

Currently we would still potentially suffer multicast packet loss if there
is just either an IGMP or an MLD querier: For the former case, we would
possibly drop IPv6 multicast packets, for the latter IPv4 ones. This is
because we are currently assuming that if either an IGMP or MLD querier
is present that the other one is present, too.

This patch makes the behaviour and fix added in
"bridge: disable snooping if there is no querier" (b00589af3b04)
to also work if there is either just an IGMP or an MLD querier on the
link: It refines the deactivation of the snooping to be protocol
specific by using separate timers for the snooped IGMP and MLD queries
as well as separate timers for our internal IGMP and MLD queriers.

Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: fix rcu check warning in multicast port group

Use of RCU here with out marked pointer and function doesn't match prototype
with sparse.

Signed-off-by: Stephen Hemminger <stephen@networkplum

bridge: fix rcu check warning in multicast port group

Use of RCU here with out marked pointer and function doesn't match prototype
with sparse.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: disable snooping if there is no querier

If there is no querier on a link then we won't get periodic reports and
therefore won't be able to learn about multicast listeners behind ports,
poten

bridge: disable snooping if there is no querier

If there is no querier on a link then we won't get periodic reports and
therefore won't be able to learn about multicast listeners behind ports,
potentially leading to lost multicast packets, especially for multicast
listeners that joined before the creation of the bridge.

These lost multicast packets can appear since c5c23260594
("bridge: Add multicast_querier toggle and disable queries by default")
in particular.

With this patch we are flooding multicast packets if our querier is
disabled and if we didn't detect any other querier.

A grace period of the Maximum Response Delay of the querier is added to
give multicast responses enough time to arrive and to be learned from
before disabling the flooding behaviour again.

Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: cleanup netpoll code

This started out with fixing a sparse warning, then I realized that
the wrapper function br_netpoll_info could just be collapsed away
by rolling it into the enable code.

bridge: cleanup netpoll code

This started out with fixing a sparse warning, then I realized that
the wrapper function br_netpoll_info could just be collapsed away
by rolling it into the enable code.

Also, eliminate unnecessary goto's

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: Add a flag to control unicast packet flood.

Add a flag to control flood of unicast traffic. By default, flood is
on and the bridge will flood unicast traffic if it doesn't know
the destinat

bridge: Add a flag to control unicast packet flood.

Add a flag to control flood of unicast traffic. By default, flood is
on and the bridge will flood unicast traffic if it doesn't know
the destination. When the flag is turned off, unicast traffic
without an FDB will not be forwarded to the specified port.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: Add flag to control mac learning.

Allow user to control whether mac learning is enabled on the port.
By default, mac learning is enabled. Disabling mac learning will
cause new dynamic FDB e

bridge: Add flag to control mac learning.

Allow user to control whether mac learning is enabled on the port.
By default, mac learning is enabled. Disabling mac learning will
cause new dynamic FDB entries to not be created for a particular port.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: only expire the mdb entry when query is received

Currently we arm the expire timer when the mdb entry is added,
however, this causes problem when there is no querier sent
out after that.

So

bridge: only expire the mdb entry when query is received

Currently we arm the expire timer when the mdb entry is added,
however, this causes problem when there is no querier sent
out after that.

So we should only arm the timer when a corresponding query is
received, as suggested by Herbert.

And he also mentioned "if there is no querier then group
subscriptions shouldn't expire. There has to be at least one querier
in the network for this thing to work. Otherwise it just degenerates
into a non-snooping switch, which is OK."

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Adam Baker <linux@baker-net.org.uk>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

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bridge: use the bridge IP addr as source addr for querier

Quote from Adam:
"If it is believed that the use of 0.0.0.0
as the IP address is what is causing strange behaviour on other devices
then is

bridge: use the bridge IP addr as source addr for querier

Quote from Adam:
"If it is believed that the use of 0.0.0.0
as the IP address is what is causing strange behaviour on other devices
then is there a good reason that a bridge rather than a router shouldn't
be the active querier? If not then using the bridge IP address and
having the querier enabled by default may be a reasonable solution
(provided that our querier obeys the election rules and shuts up if it
sees a query from a lower IP address that isn't 0.0.0.0). Just because a
device is the elected querier for IGMP doesn't appear to mean it is
required to perform any other routing functions."

And introduce a new troggle for it, as suggested by Herbert.

Suggested-by: Adam Baker <linux@baker-net.org.uk>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Adam Baker <linux@baker-net.org.uk>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

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bridge: make user modified path cost sticky

Keep a STP port path cost value if it was set by a user.
Don't replace it with the link-speed based path cost
whenever the link goes down and comes back u

bridge: make user modified path cost sticky

Keep a STP port path cost value if it was set by a user.
Don't replace it with the link-speed based path cost
whenever the link goes down and comes back up.

Reported-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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bridge: add missing vid to br_mdb_get()

Obviously, vid should be considered when searching for multicast
group.

Cc: Vlad Yasevich <vyasevic@redhat.com>
Cc: Stephen Hemminger <stephen@networkplumber

bridge: add missing vid to br_mdb_get()

Obviously, vid should be considered when searching for multicast
group.

Cc: Vlad Yasevich <vyasevic@redhat.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

bridge: Separate egress policy bitmap

Add an ability to configure a separate "untagged" egress
policy to the VLAN information of the bridge. This superseeds PVID
policy and makes PVID ingress-only.

bridge: Separate egress policy bitmap

Add an ability to configure a separate "untagged" egress
policy to the VLAN information of the bridge. This superseeds PVID
policy and makes PVID ingress-only. The policy is configured with a
new flag and is represented as a port bitmap per vlan. Egress frames
with a VLAN id in "untagged" policy bitmap would egress
the port without VLAN header.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...