There is a bug in all range dumps that rely on br_vlan_can_enter_range()
when the PVID is a range starting VLAN, all following VLANs that match
its flags can enter the range, but when the range is filled in only the
PVID VLAN is dumped and the rest of the range is discarded because
br_vlan_fill_vids() checks for the PVID flag. Since the PVID VLAN can
be only one, we need to break ranges around it, the best way to do that
consistently for all is to alter br_vlan_can_enter_range() to take into
account the PVID and return false to break the range when it's matched.
Before the fix:
$ ip l add br0 type bridge vlan_filtering 1
$ ip l add dumdum type dummy
$ ip l set dumdum master br0
$ ip l set br0 up
$ ip l set dumdum up
$ bridge vlan add dev dumdum vid 1 pvid untagged master
$ bridge vlan add dev dumdum vid 2 untagged master
$ bridge vlan show dev dumdum # use legacy dump to show all vlans
port vlan-id
dumdum 1 PVID Egress Untagged
2 Egress Untagged
$ bridge -d vlan show dev dumdum # use the new dump (RTM_GETVLAN)
port vlan-id
dumdum 1 PVID Egress Untagged
state forwarding mcast_router 1
VLAN 2 is missing, and if there are more matching VLANs afterwards
they'd be missing too.
After the fix:
[ same setup steps ]
$ bridge vlan show dev dumdum
port vlan-id
dumdum 1 PVID Egress Untagged
2 Egress Untagged
$ bridge -d vlan show dev dumdum # use the new dump (RTM_GETVLAN)
port vlan-id
dumdum 1 PVID Egress Untagged
state forwarding mcast_router 1
2 Egress Untagged
state forwarding mcast_router 1
Fixes: 0ab5587951 ("net: bridge: vlan: add rtm range support")
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260721140922.682265-2-razor@blackwall.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use BR_PROMISC_BIT and set_bit(), clear_bit() and test_bit() lockless
functions.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260604141343.2124500-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The existing neighbor suppression unconditionally suppresses gratuitous
ARPs and unsolicited Neighbor Advertisements, which prevents fast
mobility of hosts between VTEPs.
Add the neigh_forward_grat option to allow selective control of gratuitous
neighbor announcements. When neigh_suppress is enabled but
neigh_forward_grat is disabled (default), gratuitous announcements are
suppressed. When neigh_forward_grat is enabled, gratuitous announcements
are forwarded while regular neighbor discovery remains suppressed.
The implementation provides per-output-port control by:
1. Adding a 'grat_arp' flag to BR_INPUT_SKB_CB to mark gratuitous ARPs and
unsolicited NAs.
2. Setting both grat_arp and proxyarp_replied flags in
br_do_proxy_suppress_arp() and br_do_suppress_nd() when gratuitous
packets are detected.
3. Checking neigh_forward_grat per output port during flooding:
- For gratuitous ARPs/NAs: suppress unless the output port has
neigh_forward_grat enabled.
- For regular ARPs/NDs: maintain existing behavior.
This allows gratuitous announcements from any input port to be selectively
forwarded based on each output port's individual neigh_forward_grat
setting, enabling gratuitous neighbor announcements to be flooded to the
VXLAN fabric.
Regular neighbor discovery (ARP requests, NS queries, solicited replies)
remains controlled by neigh_suppress and is unaffected.
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260511065936.4173106-4-danieller@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add internal flags for the neigh_forward_grat feature:
- BR_NEIGH_FORWARD_GRAT: Port-level flag
- BR_VLFLAG_NEIGH_FORWARD_GRAT_ENABLED: Per-VLAN flag
These will be used to control whether gratuitous ARP and unsolicited NA
packets are forwarded when neighbor suppression is enabled.
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260511065936.4173106-3-danieller@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The bridge-stp usermode helper is currently restricted to the initial
network namespace, preventing userspace STP daemons (e.g. mstpd) from
operating on bridges in other network namespaces. Since commit
ff62198553 ("bridge: Only call /sbin/bridge-stp for the initial
network namespace"), bridges in non-init namespaces silently fall
back to kernel STP with no way to use userspace STP.
Add a new bridge attribute IFLA_BR_STP_MODE that allows explicit
per-bridge control over STP mode selection:
BR_STP_MODE_AUTO (default) - Existing behavior: invoke the
/sbin/bridge-stp helper in init_net only; fall back to kernel STP
if it fails or in non-init namespaces.
BR_STP_MODE_USER - Directly enable userspace STP (BR_USER_STP)
without invoking the helper. Works in any network namespace.
Userspace is responsible for ensuring an STP daemon manages the
bridge.
BR_STP_MODE_KERNEL - Directly enable kernel STP (BR_KERNEL_STP)
without invoking the helper.
The mode can only be changed while STP is disabled, or set to the
same value (-EBUSY otherwise). IFLA_BR_STP_MODE is processed before
IFLA_BR_STP_STATE in br_changelink(), so both can be set atomically
in a single netlink message. The mode can also be changed in the
same message that disables STP.
The stp_mode struct field is u8 since all possible values fit, while
NLA_U32 is used for the netlink attribute since it occupies the same
space in the netlink message as NLA_U8.
A new stp_helper_active boolean tracks whether the /sbin/bridge-stp
helper was invoked during br_stp_start(), so that br_stp_stop() only
calls the helper for stop when it was called for start. This avoids
calling the helper asymmetrically when stp_mode changes between
start and stop.
Suggested-by: Ido Schimmel <idosch@nvidia.com>
Assisted-by: Claude:claude-opus-4-6
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Andy Roulin <aroulin@nvidia.com>
Link: https://patch.msgid.link/20260405205224.3163000-2-aroulin@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In network setup as below:
fastpath bypass
.----------------------------------------.
/ \
| IP - forwarding |
| / \ v
| / wan ...
| /
| |
| |
| brlan.1
| |
| +-------------------------------+
| | vlan 1 |
| | |
| | brlan (vlan-filtering) |
| | +---------------+
| | | DSA-SWITCH |
| | vlan 1 | |
| | to | |
| | untagged 1 vlan 1 |
| +---------------+---------------+
. / \
----->wlan1 lan0
. .
. ^
^ vlan 1 tagged packets
untagged packets
br_vlan_fill_forward_path_mode() sets DEV_PATH_BR_VLAN_UNTAG_HW when
filling in from brlan.1 towards wlan1. But it should be set to
DEV_PATH_BR_VLAN_UNTAG in this case. Using BR_VLFLAG_ADDED_BY_SWITCHDEV
is not correct. The dsa switchdev adds it as a foreign port.
The same problem for all foreignly added dsa vlans on the bridge.
First add the vlan, trying only native devices.
If this fails, we know this may be a vlan from a foreign device.
Use BR_VLFLAG_TAGGING_BY_SWITCHDEV to make sure DEV_PATH_BR_VLAN_UNTAG_HW
is set only when there if no foreign device involved.
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Eric Woudstra <ericwouds@gmail.com>
Link: https://patch.msgid.link/20260317110347.363875-1-ericwouds@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The br_vlan_opts_eq_range() function determines if consecutive VLANs can
be grouped together in a range for compact netlink notifications. It
currently checks state, tunnel info, and multicast router configuration,
but misses two categories of per-VLAN options that affect the output:
1. User-visible priv_flags (neigh_suppress, mcast_enabled)
2. Port multicast context (mcast_max_groups, mcast_n_groups)
When VLANs have different settings for these options, they are incorrectly
grouped into ranges, causing netlink notifications to report only one
VLAN's settings for the entire range.
Fix by checking priv_flags equality, but only for flags that affect netlink
output (BR_VLFLAG_NEIGH_SUPPRESS_ENABLED and BR_VLFLAG_MCAST_ENABLED),
and comparing multicast context (mcast_max_groups and mcast_n_groups).
Example showing the bugs before the fix:
$ bridge vlan set vid 10 dev dummy1 neigh_suppress on
$ bridge vlan set vid 11 dev dummy1 neigh_suppress off
$ bridge -d vlan show dev dummy1
port vlan-id
dummy1 10-11
... neigh_suppress on
$ bridge vlan set vid 10 dev dummy1 mcast_max_groups 100
$ bridge vlan set vid 11 dev dummy1 mcast_max_groups 200
$ bridge -d vlan show dev dummy1
port vlan-id
dummy1 10-11
... mcast_max_groups 100
After the fix, VLANs 10 and 11 are shown as separate entries with their
correct individual settings.
Fixes: a1aee20d5d ("net: bridge: Add netlink knobs for number / maximum MDB entries")
Fixes: 83f6d60079 ("bridge: vlan: Allow setting VLAN neighbor suppression state")
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260225143956.3995415-2-danieller@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sphinx reports kernel-doc warning:
WARNING: ./net/bridge/br_private.h:267 struct member 'tunnel_hash' not described in 'net_bridge_vlan_group'
Fix it by describing @tunnel_hash member.
Fixes: efa5356b0d ("bridge: per vlan dst_metadata netlink support")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20251218042936.24175-2-bagasdotme@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
syzbot reported[1] a use-after-free when deleting an expired fdb. It is
due to a race condition between learning still happening and a port being
deleted, after all its fdbs have been flushed. The port's state has been
toggled to disabled so no learning should happen at that time, but if we
have MST enabled, it will bypass the port's state, that together with VLAN
filtering disabled can lead to fdb learning at a time when it shouldn't
happen while the port is being deleted. VLAN filtering must be disabled
because we flush the port VLANs when it's being deleted which will stop
learning. This fix adds a check for the port's vlan group which is
initialized to NULL when the port is getting deleted, that avoids the port
state bypass. When MST is enabled there would be a minimal new overhead
in the fast-path because the port's vlan group pointer is cache-hot.
[1] https://syzkaller.appspot.com/bug?extid=dd280197f0f7ab3917be
Fixes: ec7328b591 ("net: bridge: mst: Multiple Spanning Tree (MST) mode")
Reported-by: syzbot+dd280197f0f7ab3917be@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/69088ffa.050a0220.29fc44.003d.GAE@google.com/
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20251105111919.1499702-2-razor@blackwall.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The previous patches introduced a new option, BR_BOOLOPT_FDB_LOCAL_VLAN_0.
When enabled, it has local FDB entries installed only on VLAN 0, instead of
duplicating them across all VLANs.
In this patch, add the corresponding UAPI toggle, and the code for turning
the feature on and off.
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/ea99bfb10f687fa58091e6e1c2f8acc33f47ca45.1757004393.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The following patches will gradually introduce the ability of the bridge
to look up local FDB entries on VLAN 0 instead of using the VLAN indicated
by a packet.
In this patch, just introduce the option itself, with which the feature
will be linked.
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/ab85e33ef41ed19a3deaef0ff7da26830da30642.1757004393.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When set multicast_query_interval to a large value, the local variable
'time' in br_multicast_send_query() may overflow. If the time is smaller
than jiffies, the timer will expire immediately, and then call mod_timer()
again, which creates a loop and may trigger the following soft lockup
issue.
watchdog: BUG: soft lockup - CPU#1 stuck for 221s! [rb_consumer:66]
CPU: 1 UID: 0 PID: 66 Comm: rb_consumer Not tainted 6.16.0+ #259 PREEMPT(none)
Call Trace:
<IRQ>
__netdev_alloc_skb+0x2e/0x3a0
br_ip6_multicast_alloc_query+0x212/0x1b70
__br_multicast_send_query+0x376/0xac0
br_multicast_send_query+0x299/0x510
br_multicast_query_expired.constprop.0+0x16d/0x1b0
call_timer_fn+0x3b/0x2a0
__run_timers+0x619/0x950
run_timer_softirq+0x11c/0x220
handle_softirqs+0x18e/0x560
__irq_exit_rcu+0x158/0x1a0
sysvec_apic_timer_interrupt+0x76/0x90
</IRQ>
This issue can be reproduced with:
ip link add br0 type bridge
echo 1 > /sys/class/net/br0/bridge/multicast_querier
echo 0xffffffffffffffff >
/sys/class/net/br0/bridge/multicast_query_interval
ip link set dev br0 up
The multicast_startup_query_interval can also cause this issue. Similar to
the commit 99b4061095 ("net: bridge: mcast: add and enforce query
interval minimum"), add check for the query interval maximum to fix this
issue.
Link: https://lore.kernel.org/netdev/20250806094941.1285944-1-wangliang74@huawei.com/
Link: https://lore.kernel.org/netdev/20250812091818.542238-1-wangliang74@huawei.com/
Fixes: d902eee43f ("bridge: Add multicast count/interval sysfs entries")
Suggested-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Wang Liang <wangliang74@huawei.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250813021054.1643649-1-wangliang74@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cross-merge networking fixes after downstream PR (net-6.15-rc8).
Conflicts:
80f2ab46c2 ("irdma: free iwdev->rf after removing MSI-X")
4bcc063939 ("ice, irdma: fix an off by one in error handling code")
c24a65b6a2 ("iidc/ice/irdma: Update IDC to support multiple consumers")
https://lore.kernel.org/20250513130630.280ee6c5@canb.auug.org.au
No extra adjacent changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When netfilter defrag hooks are loaded (due to the presence of conntrack
rules, for example), fragmented packets entering the bridge will be
defragged by the bridge's pre-routing hook (br_nf_pre_routing() ->
ipv4_conntrack_defrag()).
Later on, in the bridge's post-routing hook, the defragged packet will
be fragmented again. If the size of the largest fragment is larger than
what the kernel has determined as the destination MTU (using
ip_skb_dst_mtu()), the defragged packet will be dropped.
Before commit ac6627a28d ("net: ipv4: Consolidate ipv4_mtu and
ip_dst_mtu_maybe_forward"), ip_skb_dst_mtu() would return dst_mtu() as
the destination MTU. Assuming the dst entry attached to the packet is
the bridge's fake rtable one, this would simply be the bridge's MTU (see
fake_mtu()).
However, after above mentioned commit, ip_skb_dst_mtu() ends up
returning the route's MTU stored in the dst entry's metrics. Ideally, in
case the dst entry is the bridge's fake rtable one, this should be the
bridge's MTU as the bridge takes care of updating this metric when its
MTU changes (see br_change_mtu()).
Unfortunately, the last operation is a no-op given the metrics attached
to the fake rtable entry are marked as read-only. Therefore,
ip_skb_dst_mtu() ends up returning 1500 (the initial MTU value) and
defragged packets are dropped during fragmentation when dealing with
large fragments and high MTU (e.g., 9k).
Fix by moving the fake rtable entry's metrics to be per-bridge (in a
similar fashion to the fake rtable entry itself) and marking them as
writable, thereby allowing MTU changes to be reflected.
Fixes: 62fa8a846d ("net: Implement read-only protection and COW'ing of metrics.")
Fixes: 33eb9873a2 ("bridge: initialize fake_rtable metrics")
Reported-by: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
Closes: https://lore.kernel.org/netdev/PH0PR10MB4504888284FF4CBA648197D0ACB82@PH0PR10MB4504.namprd10.prod.outlook.com/
Tested-by: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250515084848.727706-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When the vlan STP state is changed, which could be manipulated by
"bridge vlan" commands, similar to port STP state, this also impacts
multicast behaviors such as igmp query. In the scenario of per-VLAN
snooping, there's a need to update the corresponding multicast context
to re-arm the port query timer when vlan state becomes "forwarding" etc.
Update br_vlan_set_state() function to enable vlan multicast context
in such scenario.
Before the patch, the IGMP query does not happen in the last step of the
following test sequence, i.e. no growth for tx counter:
# ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1 mcast_vlan_snooping 1 mcast_querier 1 mcast_stats_enabled 1
# bridge vlan global set vid 1 dev br1 mcast_snooping 1 mcast_querier 1 mcast_query_interval 100 mcast_startup_query_count 0
# ip link add name swp1 up master br1 type dummy
# sleep 1
# bridge vlan set vid 1 dev swp1 state 4
# ip -j -p stats show dev swp1 group xstats_slave subgroup bridge suite mcast | jq '.[]["multicast"]["igmp_queries"]["tx_v2"]'
1
# sleep 1
# ip -j -p stats show dev swp1 group xstats_slave subgroup bridge suite mcast | jq '.[]["multicast"]["igmp_queries"]["tx_v2"]'
1
# bridge vlan set vid 1 dev swp1 state 3
# sleep 2
# ip -j -p stats show dev swp1 group xstats_slave subgroup bridge suite mcast | jq '.[]["multicast"]["igmp_queries"]["tx_v2"]'
1
After the patch, the IGMP query happens in the last step of the test:
# ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1 mcast_vlan_snooping 1 mcast_querier 1 mcast_stats_enabled 1
# bridge vlan global set vid 1 dev br1 mcast_snooping 1 mcast_querier 1 mcast_query_interval 100 mcast_startup_query_count 0
# ip link add name swp1 up master br1 type dummy
# sleep 1
# bridge vlan set vid 1 dev swp1 state 4
# ip -j -p stats show dev swp1 group xstats_slave subgroup bridge suite mcast | jq '.[]["multicast"]["igmp_queries"]["tx_v2"]'
1
# sleep 1
# ip -j -p stats show dev swp1 group xstats_slave subgroup bridge suite mcast | jq '.[]["multicast"]["igmp_queries"]["tx_v2"]'
1
# bridge vlan set vid 1 dev swp1 state 3
# sleep 2
# ip -j -p stats show dev swp1 group xstats_slave subgroup bridge suite mcast | jq '.[]["multicast"]["igmp_queries"]["tx_v2"]'
3
Signed-off-by: Yong Wang <yongwang@nvidia.com>
Reviewed-by: Andy Roulin <aroulin@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Notify user space on mdb offload failure if
mdb_offload_fail_notification is enabled.
Signed-off-by: Joseph Huang <Joseph.Huang@garmin.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250411150323.1117797-4-Joseph.Huang@garmin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add MDB_FLAGS_OFFLOAD_FAILED and MDB_PG_FLAGS_OFFLOAD_FAILED to indicate
that an attempt to offload the MDB entry to switchdev has failed.
Signed-off-by: Joseph Huang <Joseph.Huang@garmin.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250411150323.1117797-2-Joseph.Huang@garmin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
SIOCBRDELIF is passed to dev_ioctl() first and later forwarded to
br_ioctl_call(), which causes unnecessary RTNL dance and the splat
below [0] under RTNL pressure.
Let's say Thread A is trying to detach a device from a bridge and
Thread B is trying to remove the bridge.
In dev_ioctl(), Thread A bumps the bridge device's refcnt by
netdev_hold() and releases RTNL because the following br_ioctl_call()
also re-acquires RTNL.
In the race window, Thread B could acquire RTNL and try to remove
the bridge device. Then, rtnl_unlock() by Thread B will release RTNL
and wait for netdev_put() by Thread A.
Thread A, however, must hold RTNL after the unlock in dev_ifsioc(),
which may take long under RTNL pressure, resulting in the splat by
Thread B.
Thread A (SIOCBRDELIF) Thread B (SIOCBRDELBR)
---------------------- ----------------------
sock_ioctl sock_ioctl
`- sock_do_ioctl `- br_ioctl_call
`- dev_ioctl `- br_ioctl_stub
|- rtnl_lock |
|- dev_ifsioc '
' |- dev = __dev_get_by_name(...)
|- netdev_hold(dev, ...) .
/ |- rtnl_unlock ------. |
| |- br_ioctl_call `---> |- rtnl_lock
Race | | `- br_ioctl_stub |- br_del_bridge
Window | | | |- dev = __dev_get_by_name(...)
| | | May take long | `- br_dev_delete(dev, ...)
| | | under RTNL pressure | `- unregister_netdevice_queue(dev, ...)
| | | | `- rtnl_unlock
\ | |- rtnl_lock <-' `- netdev_run_todo
| |- ... `- netdev_run_todo
| `- rtnl_unlock |- __rtnl_unlock
| |- netdev_wait_allrefs_any
|- netdev_put(dev, ...) <----------------'
Wait refcnt decrement
and log splat below
To avoid blocking SIOCBRDELBR unnecessarily, let's not call
dev_ioctl() for SIOCBRADDIF and SIOCBRDELIF.
In the dev_ioctl() path, we do the following:
1. Copy struct ifreq by get_user_ifreq in sock_do_ioctl()
2. Check CAP_NET_ADMIN in dev_ioctl()
3. Call dev_load() in dev_ioctl()
4. Fetch the master dev from ifr.ifr_name in dev_ifsioc()
3. can be done by request_module() in br_ioctl_call(), so we move
1., 2., and 4. to br_ioctl_stub().
Note that 2. is also checked later in add_del_if(), but it's better
performed before RTNL.
SIOCBRADDIF and SIOCBRDELIF have been processed in dev_ioctl() since
the pre-git era, and there seems to be no specific reason to process
them there.
[0]:
unregister_netdevice: waiting for wpan3 to become free. Usage count = 2
ref_tracker: wpan3@ffff8880662d8608 has 1/1 users at
__netdev_tracker_alloc include/linux/netdevice.h:4282 [inline]
netdev_hold include/linux/netdevice.h:4311 [inline]
dev_ifsioc+0xc6a/0x1160 net/core/dev_ioctl.c:624
dev_ioctl+0x255/0x10c0 net/core/dev_ioctl.c:826
sock_do_ioctl+0x1ca/0x260 net/socket.c:1213
sock_ioctl+0x23a/0x6c0 net/socket.c:1318
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl fs/ioctl.c:892 [inline]
__x64_sys_ioctl+0x1a4/0x210 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcb/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Fixes: 893b195875 ("net: bridge: fix ioctl locking")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Reported-by: yan kang <kangyan91@outlook.com>
Reported-by: yue sun <samsun1006219@gmail.com>
Closes: https://lore.kernel.org/netdev/SY8P300MB0421225D54EB92762AE8F0F2A1D32@SY8P300MB0421.AUSP300.PROD.OUTLOOK.COM/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250316192851.19781-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The skb_buff struct in br_is_nd_neigh_msg() is never modified. Mark it as
const.
Signed-off-by: Ted Chen <znscnchen@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250104083846.71612-1-znscnchen@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When bridge binding is enabled on a VLAN netdevice, its link state should
track bridge ports that are members of the corresponding VLAN. This works
for newly-added netdevices. However toggling the option does not have the
effect of enabling or disabling the behavior as appropriate.
In this patch, react to bridge_binding toggles on VLAN uppers.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/90a8ca8aea4d81378b29d75d9e562433e0d5c7ff.1734540770.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In a similar fashion to ndo_fdb_add, which was covered in the previous
patch, add the bool *notified argument to ndo_fdb_del. Callees that send a
notification on their own set the flag to true.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/06b1acf4953ef0a5ed153ef1f32d7292044f2be6.1731589511.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently when FDB entries are added to or deleted from a VXLAN netdevice,
the VXLAN driver emits one notification, including the VXLAN-specific
attributes. The core however always sends a notification as well, a generic
one. Thus two notifications are unnecessarily sent for these operations. A
similar situation comes up with bridge driver, which also emits
notifications on its own:
# ip link add name vx type vxlan id 1000 dstport 4789
# bridge monitor fdb &
[1] 1981693
# bridge fdb add de:ad:be:ef:13:37 dev vx self dst 192.0.2.1
de:ad:be:ef:13:37 dev vx dst 192.0.2.1 self permanent
de:ad:be:ef:13:37 dev vx self permanent
In order to prevent this duplicity, add a paremeter to ndo_fdb_add,
bool *notified. The flag is primed to false, and if the callee sends a
notification on its own, it sets it to true, thus informing the core that
it should not generate another notification.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/cbf6ae8195e85cbf922f8058ce4eba770f3b71ed.1731589511.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Since introduced, br_vlan_rtnl_init() has been ignoring the returned
value of rtnl_register_module(), which could fail silently.
Handling the error allows users to view a module as an all-or-nothing
thing in terms of the rtnetlink functionality. This prevents syzkaller
from reporting spurious errors from its tests, where OOM often occurs
and module is automatically loaded.
Let's handle the errors by rtnl_register_many().
Fixes: 8dcea18708 ("net: bridge: vlan: add rtm definitions and dump support")
Fixes: f26b296585 ("net: bridge: vlan: add new rtm message support")
Fixes: adb3ce9bcb ("net: bridge: vlan: add del rtm message support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The original idea of the delay_time check was to not apply multicast
snooping too early when an MLD querier appears. And to instead wait at
least for MLD reports to arrive before switching from flooding to group
based, MLD snooped forwarding, to avoid temporary packet loss.
However in a batman-adv mesh network it was noticed that after 248 days of
uptime 32bit MIPS based devices would start to signal that they had
stopped applying multicast snooping due to missing queriers - even though
they were the elected querier and still sending MLD queries themselves.
While time_is_before_jiffies() generally is safe against jiffies
wrap-arounds, like the code comments in jiffies.h explain, it won't
be able to track a difference larger than ULONG_MAX/2. With a 32bit
large jiffies and one jiffies tick every 10ms (CONFIG_HZ=100) on these MIPS
devices running OpenWrt this would result in a difference larger than
ULONG_MAX/2 after 248 (= 2^32/100/60/60/24/2) days and
time_is_before_jiffies() would then start to return false instead of
true. Leading to multicast snooping not being applied to multicast
packets anymore.
Fix this issue by using a proper timer_list object which won't have this
ULONG_MAX/2 difference limitation.
Fixes: b00589af3b ("bridge: disable snooping if there is no querier")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20240127175033.9640-1-linus.luessing@c0d3.blue
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Implement MDB bulk deletion support in the bridge driver, allowing MDB
entries to be deleted in bulk according to provided parameters.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement support for MDB get operation by looking up a matching MDB
entry, allocating the skb according to the entry's size and then filling
in the response. The operation is performed under the bridge multicast
lock to ensure that the entry does not change between the time the reply
size is determined and when the reply is filled in.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current name is going to conflict with the upcoming net device
operation for the MDB get operation.
Rename the function to br_mdb_entry_skb_get(). No functional changes
intended.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
A malicious actor behind one bridge port may spam the kernel with packets
with a random source MAC address, each of which will create an FDB entry,
each of which is a dynamic allocation in the kernel.
There are roughly 2^48 different MAC addresses, further limited by the
rhashtable they are stored in to 2^31. Each entry is of the type struct
net_bridge_fdb_entry, which is currently 128 bytes big. This means the
maximum amount of memory allocated for FDB entries is 2^31 * 128B =
256GiB, which is too much for most computers.
Mitigate this by maintaining a per bridge count of those automatically
generated entries in fdb_n_learned, and a limit in fdb_max_learned. If
the limit is hit new entries are not learned anymore.
For backwards compatibility the default setting of 0 disables the limit.
User-added entries by netlink or from bridge or bridge port addresses
are never blocked and do not count towards that limit.
Introduce a new fdb entry flag BR_FDB_DYNAMIC_LEARNED to keep track of
whether an FDB entry is included in the count. The flag is enabled for
dynamically learned entries, and disabled for all other entries. This
should be equivalent to BR_FDB_ADDED_BY_USER and BR_FDB_LOCAL being unset,
but contrary to the two flags it can be toggled atomically.
Atomicity is required here, as there are multiple callers that modify the
flags, but are not under a common lock (br_fdb_update is the exception
for br->hash_lock, br_fdb_external_learn_add for RTNL).
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Johannes Nixdorf <jnixdorf-oss@avm.de>
Link: https://lore.kernel.org/r/20231016-fdb_limit-v5-2-32cddff87758@avm.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The merge commit 9271686937 ("Merge branch 'br-flush-filtering'")
added support for FDB flushing in bridge driver. The following patches
will extend VXLAN driver to support FDB flushing as well. The netlink
message for bulk delete is shared between the drivers. With the existing
implementation, there is no way to prevent user from flushing with
attributes that are not supported per driver. For example, when VNI will
be added, user will not get an error for flush FDB entries in bridge
with VNI, although this attribute is not relevant for bridge.
As preparation for support of FDB flush in VXLAN driver, move the policy
to be handled in bridge driver, later a new policy for VXLAN will be
added in VXLAN driver. Do not pass 'vid' as part of ndo_fdb_del_bulk(),
as this field is relevant only for bridge.
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 19e3a9c90c ("net: bridge: convert multicast to generic rhashtable")
this is not used, so can remove it.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230726143141.11704-1-yuehaibing@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When a front panel joins a bridge via another netdevice (typically a LAG),
the driver needs to learn about the objects configured on the bridge port.
When the bridge port is offloaded by the driver for the first time, this
can be achieved by passing a notifier to switchdev_bridge_port_offload().
The notifier is then invoked for the individual objects (such as VLANs)
configured on the bridge, and can look for the interesting ones.
Calling switchdev_bridge_port_offload() when the second port joins the
bridge lower is unnecessary, but the replay is still needed. To that end,
add a new function, switchdev_bridge_port_replay(), which does only the
replay part of the _offload() function in exactly the same way as that
function.
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: Ivan Vecera <ivecera@redhat.com>
Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: Nikolay Aleksandrov <razor@blackwall.org>
Cc: bridge@lists.linux-foundation.org
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new bridge port attribute that allows attaching a nexthop object
ID to an skb that is redirected to a backup bridge port with VLAN
tunneling enabled.
Specifically, when redirecting a known unicast packet, read the backup
nexthop ID from the bridge port that lost its carrier and set it in the
bridge control block of the skb before forwarding it via the backup
port. Note that reading the ID from the bridge port should not result in
a cache miss as the ID is added next to the 'backup_port' field that was
already accessed. After this change, the 'state' field still stays on
the first cache line, together with other data path related fields such
as 'flags and 'vlgrp':
struct net_bridge_port {
struct net_bridge * br; /* 0 8 */
struct net_device * dev; /* 8 8 */
netdevice_tracker dev_tracker; /* 16 0 */
struct list_head list; /* 16 16 */
long unsigned int flags; /* 32 8 */
struct net_bridge_vlan_group * vlgrp; /* 40 8 */
struct net_bridge_port * backup_port; /* 48 8 */
u32 backup_nhid; /* 56 4 */
u8 priority; /* 60 1 */
u8 state; /* 61 1 */
u16 port_no; /* 62 2 */
/* --- cacheline 1 boundary (64 bytes) --- */
[...]
} __attribute__((__aligned__(8)));
When forwarding an skb via a bridge port that has VLAN tunneling
enabled, check if the backup nexthop ID stored in the bridge control
block is valid (i.e., not zero). If so, instead of attaching the
pre-allocated metadata (that only has the tunnel key set), allocate a
new metadata, set both the tunnel key and the nexthop object ID and
attach it to the skb.
By default, do not dump the new attribute to user space as a value of
zero is an invalid nexthop object ID.
The above is useful for EVPN multihoming. When one of the links
composing an Ethernet Segment (ES) fails, traffic needs to be redirected
towards the host via one of the other ES peers. For example, if a host
is multihomed to three different VTEPs, the backup port of each ES link
needs to be set to the VXLAN device and the backup nexthop ID needs to
point to an FDB nexthop group that includes the IP addresses of the
other two VTEPs. The VXLAN driver will extract the ID from the metadata
of the redirected skb, calculate its flow hash and forward it towards
one of the other VTEPs. If the ID does not exist, or represents an
invalid nexthop object, the VXLAN driver will drop the skb. This
relieves the bridge driver from the need to validate the ID.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
For EVPN non-DF (Designated Forwarder) filtering we need to be able to
prevent decapsulated traffic from being flooded to a multi-homed host.
Filtering of multicast and broadcast traffic can be achieved using the
following flower filter:
# tc filter add dev bond0 egress pref 1 proto all flower indev vxlan0 dst_mac 01:00:00:00:00:00/01:00:00:00:00:00 action drop
Unlike broadcast and multicast traffic, it is not currently possible to
filter unknown unicast traffic. The classification into unknown unicast
is performed by the bridge driver, but is not visible to other layers
such as tc.
Solve this by adding a new 'l2_miss' bit to the tc skb extension. Clear
the bit whenever a packet enters the bridge (received from a bridge port
or transmitted via the bridge) and set it if the packet did not match an
FDB or MDB entry. If there is no skb extension and the bit needs to be
cleared, then do not allocate one as no extension is equivalent to the
bit being cleared. The bit is not set for broadcast packets as they
never perform a lookup and therefore never incur a miss.
A bit that is set for every flooded packet would also work for the
current use case, but it does not allow us to differentiate between
registered and unregistered multicast traffic, which might be useful in
the future.
To keep the performance impact to a minimum, the marking of packets is
guarded by the 'tc_skb_ext_tc' static key. When 'false', the skb is not
touched and an skb extension is not allocated. Instead, only a
5 bytes nop is executed, as demonstrated below for the call site in
br_handle_frame().
Before the patch:
```
memset(skb->cb, 0, sizeof(struct br_input_skb_cb));
c37b09: 49 c7 44 24 28 00 00 movq $0x0,0x28(%r12)
c37b10: 00 00
p = br_port_get_rcu(skb->dev);
c37b12: 49 8b 44 24 10 mov 0x10(%r12),%rax
memset(skb->cb, 0, sizeof(struct br_input_skb_cb));
c37b17: 49 c7 44 24 30 00 00 movq $0x0,0x30(%r12)
c37b1e: 00 00
c37b20: 49 c7 44 24 38 00 00 movq $0x0,0x38(%r12)
c37b27: 00 00
```
After the patch (when static key is disabled):
```
memset(skb->cb, 0, sizeof(struct br_input_skb_cb));
c37c29: 49 c7 44 24 28 00 00 movq $0x0,0x28(%r12)
c37c30: 00 00
c37c32: 49 8d 44 24 28 lea 0x28(%r12),%rax
c37c37: 48 c7 40 08 00 00 00 movq $0x0,0x8(%rax)
c37c3e: 00
c37c3f: 48 c7 40 10 00 00 00 movq $0x0,0x10(%rax)
c37c46: 00
#ifdef CONFIG_HAVE_JUMP_LABEL_HACK
static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
{
asm_volatile_goto("1:"
c37c47: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
br_tc_skb_miss_set(skb, false);
p = br_port_get_rcu(skb->dev);
c37c4c: 49 8b 44 24 10 mov 0x10(%r12),%rax
```
Subsequent patches will extend the flower classifier to be able to match
on the new 'l2_miss' bit and enable / disable the static key when
filters that match on it are added / deleted.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently, there are various places in the bridge data path that check
whether neighbor suppression is enabled on a given bridge port.
As a preparation for per-{Port, VLAN} neighbor suppression, encapsulate
this logic in a function and pass the VLAN ID of the packet as an
argument.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add two internal flags that will be used to enable / disable per-{Port,
VLAN} neighbor suppression:
1. 'BR_NEIGH_VLAN_SUPPRESS': A per-port flag used to indicate that
per-{Port, VLAN} neighbor suppression is enabled on the bridge port.
When set, 'BR_NEIGH_SUPPRESS' has no effect.
2. 'BR_VLFLAG_NEIGH_SUPPRESS_ENABLED': A per-VLAN flag used to indicate
that neighbor suppression is enabled on the given VLAN.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Subsequent patches are going to add per-{Port, VLAN} neighbor
suppression, which will require br_flood() to potentially suppress ARP /
NS packets on a per-{Port, VLAN} basis.
As a preparation, pass the VLAN ID of the packet as another argument to
br_flood().
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, the bridge driver registers handlers for MDB netlink
messages, making it impossible for other drivers to implement MDB
support.
As a preparation for VXLAN MDB support, move the MDB handlers out of the
bridge driver to the core rtnetlink code. The rtnetlink code will call
into individual drivers by invoking their previously added MDB net
device operations.
Note that while the diffstat is large, the change is mechanical. It
moves code out of the bridge driver to rtnetlink code. Also note that a
similar change was made in 2012 with commit 77162022ab ("net: add
generic PF_BRIDGE:RTM_ FDB hooks") that moved FDB handlers out of the
bridge driver to the core rtnetlink code.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement the previously added MDB net device operations in the bridge
driver so that they could be invoked by core rtnetlink code in the next
patch.
The operations are identical to the existing br_mdb_{dump,add,del}
functions. The '_new' suffix will be removed in the next patch. The
functions are re-implemented in this patch to make the conversion in the
next patch easier to review.
Add dummy implementations when 'CONFIG_BRIDGE_IGMP_SNOOPING' is
disabled, so that an error will be returned to user space when it is
trying to add or delete an MDB entry. This is consistent with existing
behavior where the bridge driver does not even register rtnetlink
handlers for RTM_{NEW,DEL,GET}MDB messages when this Kconfig option is
disabled.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The previous patch added accounting for number of MDB entries per port and
per port-VLAN, and the logic to verify that these values stay within
configured bounds. However it didn't provide means to actually configure
those bounds or read the occupancy. This patch does that.
Two new netlink attributes are added for the MDB occupancy:
IFLA_BRPORT_MCAST_N_GROUPS for the per-port occupancy and
BRIDGE_VLANDB_ENTRY_MCAST_N_GROUPS for the per-port-VLAN occupancy.
And another two for the maximum number of MDB entries:
IFLA_BRPORT_MCAST_MAX_GROUPS for the per-port maximum, and
BRIDGE_VLANDB_ENTRY_MCAST_MAX_GROUPS for the per-port-VLAN one.
Note that the two new IFLA_BRPORT_ attributes prompt bumping of
RTNL_SLAVE_MAX_TYPE to size the slave attribute tables large enough.
The new attributes are used like this:
# ip link add name br up type bridge vlan_filtering 1 mcast_snooping 1 \
mcast_vlan_snooping 1 mcast_querier 1
# ip link set dev v1 master br
# bridge vlan add dev v1 vid 2
# bridge vlan set dev v1 vid 1 mcast_max_groups 1
# bridge mdb add dev br port v1 grp 230.1.2.3 temp vid 1
# bridge mdb add dev br port v1 grp 230.1.2.4 temp vid 1
Error: bridge: Port-VLAN is already in 1 groups, and mcast_max_groups=1.
# bridge link set dev v1 mcast_max_groups 1
# bridge mdb add dev br port v1 grp 230.1.2.3 temp vid 2
Error: bridge: Port is already in 1 groups, and mcast_max_groups=1.
# bridge -d link show
5: v1@v2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 master br [...]
[...] mcast_n_groups 1 mcast_max_groups 1
# bridge -d vlan show
port vlan-id
br 1 PVID Egress Untagged
state forwarding mcast_router 1
v1 1 PVID Egress Untagged
[...] mcast_n_groups 1 mcast_max_groups 1
2
[...] mcast_n_groups 0 mcast_max_groups 0
Signed-off-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The MDB maintained by the bridge is limited. When the bridge is configured
for IGMP / MLD snooping, a buggy or malicious client can easily exhaust its
capacity. In SW datapath, the capacity is configurable through the
IFLA_BR_MCAST_HASH_MAX parameter, but ultimately is finite. Obviously a
similar limit exists in the HW datapath for purposes of offloading.
In order to prevent the issue of unilateral exhaustion of MDB resources,
introduce two parameters in each of two contexts:
- Per-port and per-port-VLAN number of MDB entries that the port
is member in.
- Per-port and (when BROPT_MCAST_VLAN_SNOOPING_ENABLED is enabled)
per-port-VLAN maximum permitted number of MDB entries, or 0 for
no limit.
The per-port multicast context is used for tracking of MDB entries for the
port as a whole. This is available for all bridges.
The per-port-VLAN multicast context is then only available on
VLAN-filtering bridges on VLANs that have multicast snooping on.
With these changes in place, it will be possible to configure MDB limit for
bridge as a whole, or any one port as a whole, or any single port-VLAN.
Note that unlike the global limit, exhaustion of the per-port and
per-port-VLAN maximums does not cause disablement of multicast snooping.
It is also permitted to configure the local limit larger than hash_max,
even though that is not useful.
In this patch, introduce only the accounting for number of entries, and the
max field itself, but not the means to toggle the max. The next patch
introduces the netlink APIs to toggle and read the values.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since cleaning up the effects of br_multicast_new_port_group() just
consists of delisting and freeing the memory, the function
br_mdb_add_group_star_g() inlines the corresponding code. In the following
patches, number of per-port and per-port-VLAN MDB entries is going to be
maintained, and that counter will have to be updated. Because that logic
is going to be hidden in the br_multicast module, introduce a new hook
intended to again remove a newly-created group.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make it possible to set an extack in br_multicast_new_port_group().
Eventually, this function will check for per-port and per-port-vlan
MDB maximums, and will use the extack to communicate the reason for
the bounce.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that user space can specify additional attributes of port group
entries such as filter mode and source list, it makes sense to allow
user space to atomically modify these attributes by replacing entries
instead of forcing user space to delete the entries and add them back.
Replace MDB port group entries when the 'NLM_F_REPLACE' flag is
specified in the netlink message header.
When a (*, G) entry is replaced, update the following attributes: Source
list, state, filter mode, protocol and flags. If the entry is temporary
and in EXCLUDE mode, reset the group timer to the group membership
interval. If the entry is temporary and in INCLUDE mode, reset the
source timers of associated sources to the group membership interval.
Examples:
# bridge mdb replace dev br0 port dummy10 grp 239.1.1.1 permanent source_list 192.0.2.1,192.0.2.2 filter_mode include
# bridge -d -s mdb show
dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.2 permanent filter_mode include proto static 0.00
dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.1 permanent filter_mode include proto static 0.00
dev br0 port dummy10 grp 239.1.1.1 permanent filter_mode include source_list 192.0.2.2/0.00,192.0.2.1/0.00 proto static 0.00
# bridge mdb replace dev br0 port dummy10 grp 239.1.1.1 permanent source_list 192.0.2.1,192.0.2.3 filter_mode exclude proto zebra
# bridge -d -s mdb show
dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.3 permanent filter_mode include proto zebra blocked 0.00
dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.1 permanent filter_mode include proto zebra blocked 0.00
dev br0 port dummy10 grp 239.1.1.1 permanent filter_mode exclude source_list 192.0.2.3/0.00,192.0.2.1/0.00 proto zebra 0.00
# bridge mdb replace dev br0 port dummy10 grp 239.1.1.1 temp source_list 192.0.2.4,192.0.2.3 filter_mode include proto bgp
# bridge -d -s mdb show
dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.4 temp filter_mode include proto bgp 0.00
dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.3 temp filter_mode include proto bgp 0.00
dev br0 port dummy10 grp 239.1.1.1 temp filter_mode include source_list 192.0.2.4/259.44,192.0.2.3/259.44 proto bgp 0.00
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add the 'MDBE_ATTR_RTPORT' attribute to allow user space to specify the
routing protocol of the MDB port group entry. Enforce a minimum value of
'RTPROT_STATIC' to prevent user space from using protocol values that
should only be set by the kernel (e.g., 'RTPROT_KERNEL'). Maintain
backward compatibility by defaulting to 'RTPROT_STATIC'.
The protocol is already visible to user space in RTM_NEWMDB responses
and notifications via the 'MDBA_MDB_EATTR_RTPROT' attribute.
The routing protocol allows a routing daemon to distinguish between
entries configured by it and those configured by the administrator. Once
MDB flush is supported, the protocol can be used as a criterion
according to which the flush is performed.
Examples:
# bridge mdb add dev br0 port dummy10 grp 239.1.1.1 permanent proto kernel
Error: integer out of range.
# bridge mdb add dev br0 port dummy10 grp 239.1.1.1 permanent proto static
# bridge mdb add dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.1 permanent proto zebra
# bridge mdb add dev br0 port dummy10 grp 239.1.1.2 permanent source_list 198.51.100.1,198.51.100.2 filter_mode include proto 250
# bridge -d mdb show
dev br0 port dummy10 grp 239.1.1.2 src 198.51.100.2 permanent filter_mode include proto 250
dev br0 port dummy10 grp 239.1.1.2 src 198.51.100.1 permanent filter_mode include proto 250
dev br0 port dummy10 grp 239.1.1.2 permanent filter_mode include source_list 198.51.100.2/0.00,198.51.100.1/0.00 proto 250
dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.1 permanent filter_mode include proto zebra
dev br0 port dummy10 grp 239.1.1.1 permanent filter_mode exclude proto static
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In preparation for allowing user space to add (*, G) entries with a
source list and associated filter mode, add the necessary plumbing to
handle such requests.
Extend the MDB configuration structure with a currently empty source
array and filter mode that is currently hard coded to EXCLUDE.
Add the source entries and the corresponding (S, G) entries before
making the new (*, G) port group entry visible to the data path.
Handle the creation of each source entry in a similar fashion to how it
is created from the data path in response to received Membership
Reports: Create the source entry, arm the source timer (if needed), add
a corresponding (S, G) forwarding entry and finally mark the source
entry as installed (by user space).
Add the (S, G) entry by populating an MDB configuration structure and
calling br_mdb_add_group_sg() as if a new entry is created by user
space, with the sole difference that the 'src_entry' field is set to
make sure that the group timer of such entries is never armed.
Note that it is not currently possible to add more than 32 source
entries to a port group entry. If this proves to be a problem we can
either increase 'PG_SRC_ENT_LIMIT' or avoid forcing a limit on entries
created by user space.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
