Commit Graph

2488 Commits

Author SHA1 Message Date
YueHaibing
4d66f235c7 bridge: Remove unused declaration br_multicast_set_hash_max()
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>
2023-07-27 17:11:29 -07:00
Petr Machata
f2e2857b35 net: switchdev: Add a helper to replay objects on a bridge port
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>
2023-07-21 08:54:03 +01:00
Petr Machata
989280d6ea net: bridge: br_switchdev: Tolerate -EOPNOTSUPP when replaying MDB
There are two kinds of MDB entries to be replayed: port MDB entries, and
host MDB entries. They are both replayed by br_switchdev_mdb_replay(). If
the driver supports one kind, but lacks the other, the first -EOPNOTSUPP
returned terminates the whole replay, including any further still-supported
objects in the list.

For this to cause issues, there must be MDB entries for both the host and
the port being replayed. In that case, if the driver bails out from
handling the host entry, the port entries are never replayed. However, the
replay is currently only done when a switchdev port joins a bridge. There
would be no port memberships at that point. Thus despite being erroneous,
the code does not cause observable bugs.

This is not an issue with other object kinds either, because there, each
function replays one object kind. If a driver does not support that kind,
it makes sense to bail out early. -EOPNOTSUPP is then ignored in
nbp_switchdev_sync_objs().

For MDB, suppress the -EOPNOTSUPP error code in br_switchdev_mdb_replay()
already, so that the whole list gets replayed.

The reason we need this patch is that a future patch will introduce a
replay that should be used when a front-panel port netdevice is enslaved to
a bridge lower, in particular a LAG. The LAG netdevice can already have
both host and port MDB entries. The port entries need to be replayed so
that they are offloaded on the port that joins the LAG.

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>
2023-07-21 08:54:03 +01:00
Ido Schimmel
29cfb2aaa4 bridge: Add backup nexthop ID support
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>
2023-07-19 10:53:49 +01:00
Vladimir Oltean
6ca3c005d0 net: bridge: keep ports without IFF_UNICAST_FLT in BR_PROMISC mode
According to the synchronization rules for .ndo_get_stats() as seen in
Documentation/networking/netdevices.rst, acquiring a plain spin_lock()
should not be illegal, but the bridge driver implementation makes it so.

After running these commands, I am being faced with the following
lockdep splat:

$ ip link add link swp0 name macsec0 type macsec encrypt on && ip link set swp0 up
$ ip link add dev br0 type bridge vlan_filtering 1 && ip link set br0 up
$ ip link set macsec0 master br0 && ip link set macsec0 up

  ========================================================
  WARNING: possible irq lock inversion dependency detected
  6.4.0-04295-g31b577b4bd4a #603 Not tainted
  --------------------------------------------------------
  swapper/1/0 just changed the state of lock:
  ffff6bd348724cd8 (&br->lock){+.-.}-{3:3}, at: br_forward_delay_timer_expired+0x34/0x198
  but this lock took another, SOFTIRQ-unsafe lock in the past:
   (&ocelot->stats_lock){+.+.}-{3:3}

  and interrupts could create inverse lock ordering between them.

  other info that might help us debug this:
  Chain exists of:
    &br->lock --> &br->hash_lock --> &ocelot->stats_lock

   Possible interrupt unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(&ocelot->stats_lock);
                                 local_irq_disable();
                                 lock(&br->lock);
                                 lock(&br->hash_lock);
    <Interrupt>
      lock(&br->lock);

   *** DEADLOCK ***

(details about the 3 locks skipped)

swp0 is instantiated by drivers/net/dsa/ocelot/felix.c, and this
only matters to the extent that its .ndo_get_stats64() method calls
spin_lock(&ocelot->stats_lock).

Documentation/locking/lockdep-design.rst says:

| A lock is irq-safe means it was ever used in an irq context, while a lock
| is irq-unsafe means it was ever acquired with irq enabled.

(...)

| Furthermore, the following usage based lock dependencies are not allowed
| between any two lock-classes::
|
|    <hardirq-safe>   ->  <hardirq-unsafe>
|    <softirq-safe>   ->  <softirq-unsafe>

Lockdep marks br->hash_lock as softirq-safe, because it is sometimes
taken in softirq context (for example br_fdb_update() which runs in
NET_RX softirq), and when it's not in softirq context it blocks softirqs
by using spin_lock_bh().

Lockdep marks ocelot->stats_lock as softirq-unsafe, because it never
blocks softirqs from running, and it is never taken from softirq
context. So it can always be interrupted by softirqs.

There is a call path through which a function that holds br->hash_lock:
fdb_add_hw_addr() will call a function that acquires ocelot->stats_lock:
ocelot_port_get_stats64(). This can be seen below:

ocelot_port_get_stats64+0x3c/0x1e0
felix_get_stats64+0x20/0x38
dsa_slave_get_stats64+0x3c/0x60
dev_get_stats+0x74/0x2c8
rtnl_fill_stats+0x4c/0x150
rtnl_fill_ifinfo+0x5cc/0x7b8
rtmsg_ifinfo_build_skb+0xe4/0x150
rtmsg_ifinfo+0x5c/0xb0
__dev_notify_flags+0x58/0x200
__dev_set_promiscuity+0xa0/0x1f8
dev_set_promiscuity+0x30/0x70
macsec_dev_change_rx_flags+0x68/0x88
__dev_set_promiscuity+0x1a8/0x1f8
__dev_set_rx_mode+0x74/0xa8
dev_uc_add+0x74/0xa0
fdb_add_hw_addr+0x68/0xd8
fdb_add_local+0xc4/0x110
br_fdb_add_local+0x54/0x88
br_add_if+0x338/0x4a0
br_add_slave+0x20/0x38
do_setlink+0x3a4/0xcb8
rtnl_newlink+0x758/0x9d0
rtnetlink_rcv_msg+0x2f0/0x550
netlink_rcv_skb+0x128/0x148
rtnetlink_rcv+0x24/0x38

the plain English explanation for it is:

The macsec0 bridge port is created without p->flags & BR_PROMISC,
because it is what br_manage_promisc() decides for a VLAN filtering
bridge with a single auto port.

As part of the br_add_if() procedure, br_fdb_add_local() is called for
the MAC address of the device, and this results in a call to
dev_uc_add() for macsec0 while the softirq-safe br->hash_lock is taken.

Because macsec0 does not have IFF_UNICAST_FLT, dev_uc_add() ends up
calling __dev_set_promiscuity() for macsec0, which is propagated by its
implementation, macsec_dev_change_rx_flags(), to the lower device: swp0.
This triggers the call path:

dev_set_promiscuity(swp0)
-> rtmsg_ifinfo()
   -> dev_get_stats()
      -> ocelot_port_get_stats64()

with a calling context that lockdep doesn't like (br->hash_lock held).

Normally we don't see this, because even though many drivers that can be
bridge ports don't support IFF_UNICAST_FLT, we need a driver that

(a) doesn't support IFF_UNICAST_FLT, *and*
(b) it forwards the IFF_PROMISC flag to another driver, and
(c) *that* driver implements ndo_get_stats64() using a softirq-unsafe
    spinlock.

Condition (b) is necessary because the first __dev_set_rx_mode() calls
__dev_set_promiscuity() with "bool notify=false", and thus, the
rtmsg_ifinfo() code path won't be entered.

The same criteria also hold true for DSA switches which don't report
IFF_UNICAST_FLT. When the DSA master uses a spin_lock() in its
ndo_get_stats64() method, the same lockdep splat can be seen.

I think the deadlock possibility is real, even though I didn't reproduce
it, and I'm thinking of the following situation to support that claim:

fdb_add_hw_addr() runs on a CPU A, in a context with softirqs locally
disabled and br->hash_lock held, and may end up attempting to acquire
ocelot->stats_lock.

In parallel, ocelot->stats_lock is currently held by a thread B (say,
ocelot_check_stats_work()), which is interrupted while holding it by a
softirq which attempts to lock br->hash_lock.

Thread B cannot make progress because br->hash_lock is held by A. Whereas
thread A cannot make progress because ocelot->stats_lock is held by B.

When taking the issue at face value, the bridge can avoid that problem
by simply making the ports promiscuous from a code path with a saner
calling context (br->hash_lock not held). A bridge port without
IFF_UNICAST_FLT is going to become promiscuous as soon as we call
dev_uc_add() on it (which we do unconditionally), so why not be
preemptive and make it promiscuous right from the beginning, so as to
not be taken by surprise.

With this, we've broken the links between code that holds br->hash_lock
or br->lock and code that calls into the ndo_change_rx_flags() or
ndo_get_stats64() ops of the bridge port.

Fixes: 2796d0c648 ("bridge: Automatically manage port promiscuous mode.")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-07-03 09:11:34 +01:00
Ido Schimmel
7b4858df3b skbuff: bridge: Add layer 2 miss indication
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>
2023-05-30 23:37:00 -07:00
Arnd Bergmann
89dcd87ce5 bridge: always declare tunnel functions
When CONFIG_BRIDGE_VLAN_FILTERING is disabled, two functions are still
defined but have no prototype or caller. This causes a W=1 warning for
the missing prototypes:

net/bridge/br_netlink_tunnel.c:29:6: error: no previous prototype for 'vlan_tunid_inrange' [-Werror=missing-prototypes]
net/bridge/br_netlink_tunnel.c:199:5: error: no previous prototype for 'br_vlan_tunnel_info' [-Werror=missing-prototypes]

The functions are already contitional on CONFIG_BRIDGE_VLAN_FILTERING,
and I coulnd't easily figure out the right set of #ifdefs, so just
move the declarations out of the #ifdef to avoid the warning,
at a small cost in code size over a more elaborate fix.

Fixes: 188c67dd19 ("net: bridge: vlan options: add support for tunnel id dumping")
Fixes: 569da08228 ("net: bridge: vlan options: add support for tunnel mapping set/del")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230516194625.549249-3-arnd@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-17 21:28:58 -07:00
Eric Dumazet
4063384ef7 net: add vlan_get_protocol_and_depth() helper
Before blamed commit, pskb_may_pull() was used instead
of skb_header_pointer() in __vlan_get_protocol() and friends.

Few callers depended on skb->head being populated with MAC header,
syzbot caught one of them (skb_mac_gso_segment())

Add vlan_get_protocol_and_depth() to make the intent clearer
and use it where sensible.

This is a more generic fix than commit e9d3f80935
("net/af_packet: make sure to pull mac header") which was
dealing with a similar issue.

kernel BUG at include/linux/skbuff.h:2655 !
invalid opcode: 0000 [#1] SMP KASAN
CPU: 0 PID: 1441 Comm: syz-executor199 Not tainted 6.1.24-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
RIP: 0010:__skb_pull include/linux/skbuff.h:2655 [inline]
RIP: 0010:skb_mac_gso_segment+0x68f/0x6a0 net/core/gro.c:136
Code: fd 48 8b 5c 24 10 44 89 6b 70 48 c7 c7 c0 ae 0d 86 44 89 e6 e8 a1 91 d0 00 48 c7 c7 00 af 0d 86 48 89 de 31 d2 e8 d1 4a e9 ff <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41
RSP: 0018:ffffc90001bd7520 EFLAGS: 00010286
RAX: ffffffff8469736a RBX: ffff88810f31dac0 RCX: ffff888115a18b00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90001bd75e8 R08: ffffffff84697183 R09: fffff5200037adf9
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000012
R13: 000000000000fee5 R14: 0000000000005865 R15: 000000000000fed7
FS: 000055555633f300(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 0000000116fea000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
[<ffffffff847018dd>] __skb_gso_segment+0x32d/0x4c0 net/core/dev.c:3419
[<ffffffff8470398a>] skb_gso_segment include/linux/netdevice.h:4819 [inline]
[<ffffffff8470398a>] validate_xmit_skb+0x3aa/0xee0 net/core/dev.c:3725
[<ffffffff84707042>] __dev_queue_xmit+0x1332/0x3300 net/core/dev.c:4313
[<ffffffff851a9ec7>] dev_queue_xmit+0x17/0x20 include/linux/netdevice.h:3029
[<ffffffff851b4a82>] packet_snd net/packet/af_packet.c:3111 [inline]
[<ffffffff851b4a82>] packet_sendmsg+0x49d2/0x6470 net/packet/af_packet.c:3142
[<ffffffff84669a12>] sock_sendmsg_nosec net/socket.c:716 [inline]
[<ffffffff84669a12>] sock_sendmsg net/socket.c:736 [inline]
[<ffffffff84669a12>] __sys_sendto+0x472/0x5f0 net/socket.c:2139
[<ffffffff84669c75>] __do_sys_sendto net/socket.c:2151 [inline]
[<ffffffff84669c75>] __se_sys_sendto net/socket.c:2147 [inline]
[<ffffffff84669c75>] __x64_sys_sendto+0xe5/0x100 net/socket.c:2147
[<ffffffff8551d40f>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff8551d40f>] do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80
[<ffffffff85600087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: 469aceddfa ("vlan: consolidate VLAN parsing code and limit max parsing depth")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Cc: Willem de Bruijn <willemb@google.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-10 10:25:55 +01:00
Ido Schimmel
160656d720 bridge: Allow setting per-{Port, VLAN} neighbor suppression state
Add a new bridge port attribute that allows user space to enable
per-{Port, VLAN} neighbor suppression. Example:

 # bridge -d -j -p link show dev swp1 | jq '.[]["neigh_vlan_suppress"]'
 false
 # bridge link set dev swp1 neigh_vlan_suppress on
 # bridge -d -j -p link show dev swp1 | jq '.[]["neigh_vlan_suppress"]'
 true
 # bridge link set dev swp1 neigh_vlan_suppress off
 # bridge -d -j -p link show dev swp1 | jq '.[]["neigh_vlan_suppress"]'
 false

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-21 08:25:50 +01:00
Ido Schimmel
83f6d60079 bridge: vlan: Allow setting VLAN neighbor suppression state
Add a new VLAN attribute that allows user space to set the neighbor
suppression state of the port VLAN. Example:

 # bridge -d -j -p vlan show dev swp1 vid 10 | jq '.[]["vlans"][]["neigh_suppress"]'
 false
 # bridge vlan set vid 10 dev swp1 neigh_suppress on
 # bridge -d -j -p vlan show dev swp1 vid 10 | jq '.[]["vlans"][]["neigh_suppress"]'
 true
 # bridge vlan set vid 10 dev swp1 neigh_suppress off
 # bridge -d -j -p vlan show dev swp1 vid 10 | jq '.[]["vlans"][]["neigh_suppress"]'
 false

 # bridge vlan set vid 10 dev br0 neigh_suppress on
 Error: bridge: Can't set neigh_suppress for non-port vlans.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-21 08:25:50 +01:00
Ido Schimmel
412614b145 bridge: Add per-{Port, VLAN} neighbor suppression data path support
When the bridge is not VLAN-aware (i.e., VLAN ID is 0), determine if
neighbor suppression is enabled on a given bridge port solely based on
the existing 'BR_NEIGH_SUPPRESS' flag.

Otherwise, if the bridge is VLAN-aware, first check if per-{Port, VLAN}
neighbor suppression is enabled on the given bridge port using the
'BR_NEIGH_VLAN_SUPPRESS' flag. If so, look up the VLAN and check whether
it has neighbor suppression enabled based on the per-VLAN
'BR_VLFLAG_NEIGH_SUPPRESS_ENABLED' flag.

If the bridge is VLAN-aware, but the bridge port does not have
per-{Port, VLAN} neighbor suppression enabled, then fallback to
determine neighbor suppression based on the 'BR_NEIGH_SUPPRESS' flag.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-21 08:25:50 +01:00
Ido Schimmel
3aca683e06 bridge: Encapsulate data path neighbor suppression logic
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>
2023-04-21 08:25:50 +01:00
Ido Schimmel
6be42ed0a5 bridge: Take per-{Port, VLAN} neighbor suppression into account
The bridge driver gates the neighbor suppression code behind an internal
per-bridge flag called 'BROPT_NEIGH_SUPPRESS_ENABLED'. The flag is set
when at least one bridge port has neighbor suppression enabled.

As a preparation for per-{Port, VLAN} neighbor suppression, make sure
the global flag is also set if per-{Port, VLAN} neighbor suppression is
enabled. That is, when the 'BR_NEIGH_VLAN_SUPPRESS' flag is set on at
least one bridge port.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-21 08:25:49 +01:00
Ido Schimmel
a714e3ec23 bridge: Add internal flags for per-{Port, VLAN} neighbor suppression
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>
2023-04-21 08:25:49 +01:00
Ido Schimmel
e408336a69 bridge: Pass VLAN ID to br_flood()
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>
2023-04-21 08:25:49 +01:00
Ido Schimmel
013a7ce81d bridge: Reorder neighbor suppression check when flooding
The bridge does not flood ARP / NS packets for which a reply was sent to
bridge ports that have neighbor suppression enabled.

Subsequent patches are going to add per-{Port, VLAN} neighbor
suppression, which is going to make it more expensive to check whether
neighbor suppression is enabled since a VLAN lookup will be required.

Therefore, instead of unnecessarily performing this lookup for every
packet, only perform it for ARP / NS packets for which a reply was sent.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-21 08:25:49 +01:00
Jakub Kicinski
681c5b51dc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Adjacent changes:

net/mptcp/protocol.h
  63740448a3 ("mptcp: fix accept vs worker race")
  2a6a870e44 ("mptcp: stops worker on unaccepted sockets at listener close")
  ddb1a072f8 ("mptcp: move first subflow allocation at mpc access time")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-20 16:29:51 -07:00
Vladimir Oltean
927cdea5d2 net: bridge: switchdev: don't notify FDB entries with "master dynamic"
There is a structural problem in switchdev, where the flag bits in
struct switchdev_notifier_fdb_info (added_by_user, is_local etc) only
represent a simplified / denatured view of what's in struct
net_bridge_fdb_entry :: flags (BR_FDB_ADDED_BY_USER, BR_FDB_LOCAL etc).
Each time we want to pass more information about struct
net_bridge_fdb_entry :: flags to struct switchdev_notifier_fdb_info
(here, BR_FDB_STATIC), we find that FDB entries were already notified to
switchdev with no regard to this flag, and thus, switchdev drivers had
no indication whether the notified entries were static or not.

For example, this command:

ip link add br0 type bridge && ip link set swp0 master br0
bridge fdb add dev swp0 00:01:02:03:04:05 master dynamic

has never worked as intended with switchdev. It causes a struct
net_bridge_fdb_entry to be passed to br_switchdev_fdb_notify() which has
a single flag set: BR_FDB_ADDED_BY_USER.

This is further passed to the switchdev notifier chain, where interested
drivers have no choice but to assume this is a static (does not age) and
sticky (does not migrate) FDB entry. So currently, all drivers offload
it to hardware as such, as can be seen below ("offload" is set).

bridge fdb get 00:01:02:03:04:05 dev swp0 master
00:01:02:03:04:05 dev swp0 offload master br0

The software FDB entry expires $ageing_time centiseconds after the
kernel last sees a packet with this MAC SA, and the bridge notifies its
deletion as well, so it eventually disappears from hardware too.

This is a problem, because it is actually desirable to start offloading
"master dynamic" FDB entries correctly - they should expire $ageing_time
centiseconds after the *hardware* port last sees a packet with this
MAC SA - and this is how the current incorrect behavior was discovered.
With an offloaded data plane, it can be expected that software only sees
exception path packets, so an otherwise active dynamic FDB entry would
be aged out by software sooner than it should.

With the change in place, these FDB entries are no longer offloaded:

bridge fdb get 00:01:02:03:04:05 dev swp0 master
00:01:02:03:04:05 dev swp0 master br0

and this also constitutes a better way (assuming a backport to stable
kernels) for user space to determine whether the kernel has the
capability of doing something sane with these or not.

As opposed to "master dynamic" FDB entries, on the current behavior of
which no one currently depends on (which can be deduced from the lack of
kselftests), Ido Schimmel explains that entries with the "extern_learn"
flag (BR_FDB_ADDED_BY_EXT_LEARN) should still be notified to switchdev,
since the spectrum driver listens to them (and this is kind of okay,
because although they are treated identically to "static", they are
expected to not age, and to roam).

Fixes: 6b26b51b1d ("net: bridge: Add support for notifying devices about FDB add/del")
Link: https://lore.kernel.org/netdev/20230327115206.jk5q5l753aoelwus@skbuf/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20230418155902.898627-1-vladimir.oltean@nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-04-20 09:20:14 +02:00
Florian Westphal
94623f579c netfilter: br_netfilter: fix recent physdev match breakage
Recent attempt to ensure PREROUTING hook is executed again when a
decrypted ipsec packet received on a bridge passes through the network
stack a second time broke the physdev match in INPUT hook.

We can't discard the nf_bridge info strct from sabotage_in hook, as
this is needed by the physdev match.

Keep the struct around and handle this with another conditional instead.

Fixes: 2b272bb558 ("netfilter: br_netfilter: disable sabotage_in hook after first suppression")
Reported-and-tested-by: Farid BENAMROUCHE <fariouche@yahoo.fr>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-06 11:33:52 +02:00
Thomas Gleixner
bc9d3a9f2a net: dst: Switch to rcuref_t reference counting
Under high contention dst_entry::__refcnt becomes a significant bottleneck.

atomic_inc_not_zero() is implemented with a cmpxchg() loop, which goes into
high retry rates on contention.

Switch the reference count to rcuref_t which results in a significant
performance gain. Rename the reference count member to __rcuref to reflect
the change.

The gain depends on the micro-architecture and the number of concurrent
operations and has been measured in the range of +25% to +130% with a
localhost memtier/memcached benchmark which amplifies the problem
massively.

Running the memtier/memcached benchmark over a real (1Gb) network
connection the conversion on top of the false sharing fix for struct
dst_entry::__refcnt results in a total gain in the 2%-5% range over the
upstream baseline.

Reported-by: Wangyang Guo <wangyang.guo@intel.com>
Reported-by: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230307125538.989175656@linutronix.de
Link: https://lore.kernel.org/r/20230323102800.215027837@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 18:52:28 -07:00
Ido Schimmel
da654c80a0 rtnetlink: bridge: mcast: Relax group address validation in common code
In the upcoming VXLAN MDB implementation, the 0.0.0.0 and :: MDB entries
will act as catchall entries for unregistered IP multicast traffic in a
similar fashion to the 00:00:00:00:00:00 VXLAN FDB entry that is used to
transmit BUM traffic.

In deployments where inter-subnet multicast forwarding is used, not all
the VTEPs in a tenant domain are members in all the broadcast domains.
It is therefore advantageous to transmit BULL (broadcast, unknown
unicast and link-local multicast) and unregistered IP multicast traffic
on different tunnels. If the same tunnel was used, a VTEP only
interested in IP multicast traffic would also pull all the BULL traffic
and drop it as it is not a member in the originating broadcast domain
[1].

Prepare for this change by allowing the 0.0.0.0 group address in the
common rtnetlink MDB code and forbid it in the bridge driver. A similar
change is not needed for IPv6 because the common code only validates
that the group address is not the all-nodes address.

[1] https://datatracker.ietf.org/doc/html/draft-ietf-bess-evpn-irb-mcast#section-2.6

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-17 08:05:49 +00:00
Ido Schimmel
cc7f5022f8 rtnetlink: bridge: mcast: Move MDB handlers out of bridge driver
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>
2023-03-17 08:05:48 +00:00
Ido Schimmel
c009de1061 bridge: mcast: Implement MDB net device operations
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>
2023-03-17 08:05:48 +00:00
Eric Dumazet
b071af5235 neighbour: annotate lockless accesses to n->nud_state
We have many lockless accesses to n->nud_state.

Before adding another one in the following patch,
add annotations to readers and writers.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-15 00:37:32 -07:00
Xin Long
28e144cf5f netfilter: move br_nf_check_hbh_len to utils
Rename br_nf_check_hbh_len() to nf_ip6_check_hbh_len() and move it
to netfilter utils, so that it can be used by other modules, like
ovs and tc.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-03-08 14:25:40 +01:00
Xin Long
0b24bd71a6 netfilter: bridge: move pskb_trim_rcsum out of br_nf_check_hbh_len
br_nf_check_hbh_len() is a function to check the Hop-by-hop option
header, and shouldn't do pskb_trim_rcsum() there. This patch is to
pass pkt_len out to br_validate_ipv6() and do pskb_trim_rcsum()
after calling br_validate_ipv6() instead.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-03-08 14:25:40 +01:00
Xin Long
a7f1a2f43e netfilter: bridge: check len before accessing more nh data
In the while loop of br_nf_check_hbh_len(), similar to ip6_parse_tlv(),
before accessing 'nh[off + 1]', it should add a check 'len < 2'; and
before parsing IPV6_TLV_JUMBO, it should add a check 'optlen > len',
in case of overflows.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-03-08 14:25:39 +01:00
Xin Long
9ccff83b13 netfilter: bridge: call pskb_may_pull in br_nf_check_hbh_len
When checking Hop-by-hop option header, if the option data is in
nonlinear area, it should do pskb_may_pull instead of discarding
the skb as a bad IPv6 packet.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-03-08 14:25:38 +01:00
Sriram Yagnaraman
4386b92185 netfilter: bridge: introduce broute meta statement
nftables equivalent for ebtables -t broute.

Implement broute meta statement to set br_netfilter_broute flag
in skb to force a packet to be routed instead of being bridged.

Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-03-08 14:21:18 +01:00
Jakub Kicinski
fd2a55e74a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

1) Fix broken listing of set elements when table has an owner.

2) Fix conntrack refcount leak in ctnetlink with related conntrack
   entries, from Hangyu Hua.

3) Fix use-after-free/double-free in ctnetlink conntrack insert path,
   from Florian Westphal.

4) Fix ip6t_rpfilter with VRF, from Phil Sutter.

5) Fix use-after-free in ebtables reported by syzbot, also from Florian.

6) Use skb->len in xt_length to deal with IPv6 jumbo packets,
   from Xin Long.

7) Fix NETLINK_LISTEN_ALL_NSID with ctnetlink, from Florian Westphal.

8) Fix memleak in {ip_,ip6_,arp_}tables in ENOMEM error case,
   from Pavel Tikhomirov.

* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: x_tables: fix percpu counter block leak on error path when creating new netns
  netfilter: ctnetlink: make event listener tracking global
  netfilter: xt_length: use skb len to match in length_mt6
  netfilter: ebtables: fix table blob use-after-free
  netfilter: ip6t_rpfilter: Fix regression with VRF interfaces
  netfilter: conntrack: fix rmmod double-free race
  netfilter: ctnetlink: fix possible refcount leak in ctnetlink_create_conntrack()
  netfilter: nf_tables: allow to fetch set elements when table has an owner
====================

Link: https://lore.kernel.org/r/20230222092137.88637-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-22 21:25:23 -08:00
Florian Westphal
e58a171d35 netfilter: ebtables: fix table blob use-after-free
We are not allowed to return an error at this point.
Looking at the code it looks like ret is always 0 at this
point, but its not.

t = find_table_lock(net, repl->name, &ret, &ebt_mutex);

... this can return a valid table, with ret != 0.

This bug causes update of table->private with the new
blob, but then frees the blob right away in the caller.

Syzbot report:

BUG: KASAN: vmalloc-out-of-bounds in __ebt_unregister_table+0xc00/0xcd0 net/bridge/netfilter/ebtables.c:1168
Read of size 4 at addr ffffc90005425000 by task kworker/u4:4/74
Workqueue: netns cleanup_net
Call Trace:
 kasan_report+0xbf/0x1f0 mm/kasan/report.c:517
 __ebt_unregister_table+0xc00/0xcd0 net/bridge/netfilter/ebtables.c:1168
 ebt_unregister_table+0x35/0x40 net/bridge/netfilter/ebtables.c:1372
 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:169
 cleanup_net+0x4ee/0xb10 net/core/net_namespace.c:613
...

ip(6)tables appears to be ok (ret should be 0 at this point) but make
this more obvious.

Fixes: c58dd2dd44 ("netfilter: Can't fail and free after table replacement")
Reported-by: syzbot+f61594de72d6705aea03@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-02-22 00:22:31 +01:00
Thomas Weißschuh
e8c6cbd765 net: bridge: make kobj_type structure constant
Since commit ee6d3dd4ed ("driver core: make kobj_type constant.")
the driver core allows the usage of const struct kobj_type.

Take advantage of this to constify the structure definition to prevent
modification at runtime.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-14 20:48:08 -08:00
Ido Schimmel
170afa71e3 bridge: mcast: Move validation to a policy
Future patches are going to move parts of the bridge MDB code to the
common rtnetlink code in preparation for VXLAN MDB support. To
facilitate code sharing between both drivers, move the validation of the
top level attributes in RTM_{NEW,DEL}MDB messages to a policy that will
eventually be moved to the rtnetlink code.

Use 'NLA_NESTED' for 'MDBA_SET_ENTRY_ATTRS' instead of
NLA_POLICY_NESTED() as this attribute is going to be validated using
different policies in the underlying drivers.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-10 19:21:13 -08:00
Ido Schimmel
7ea829664d bridge: mcast: Remove pointless sequence generation counter assignment
The purpose of the sequence generation counter in the netlink callback
is to identify if a multipart dump is consistent or not by calling
nl_dump_check_consistent() whenever a message is generated.

The function is not invoked by the MDB code, rendering the sequence
generation counter assignment pointless. Remove it.

Note that even if the function was invoked, we still could not
accurately determine if the dump is consistent or not, as there is no
sequence generation counter for MDB entries, unlike nexthop objects, for
example.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-10 19:21:13 -08:00
Ido Schimmel
ccd7f25b5b bridge: mcast: Use correct define in MDB dump
'MDB_PG_FLAGS_PERMANENT' and 'MDB_PERMANENT' happen to have the same
value, but the latter is uAPI and cannot change, so use it when dumping
an MDB entry.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-10 19:21:13 -08:00
Petr Machata
a1aee20d5d net: bridge: Add netlink knobs for number / maximum MDB entries
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>
2023-02-06 08:48:26 +00:00
Petr Machata
b57e8d870d net: bridge: Maintain number of MDB entries in net_bridge_mcast_port
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>
2023-02-06 08:48:26 +00:00
Petr Machata
eceb30854f net: bridge: Change a cleanup in br_multicast_new_port_group() to goto
This function is getting more to clean up in the following patches.
Structuring the cleanups in one labeled block will allow reusing the same
cleanup from several places.

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>
2023-02-06 08:48:25 +00:00
Petr Machata
976b3858dd net: bridge: Add br_multicast_del_port_group()
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>
2023-02-06 08:48:25 +00:00
Petr Machata
1c85b80b20 net: bridge: Move extack-setting to br_multicast_new_port_group()
Now that br_multicast_new_port_group() takes an extack argument, move
setting the extack there. The downside is that the error messages end
up being less specific (the function cannot distinguish between (S,G)
and (*,G) groups). However, the alternative is to check in the caller
whether the callee set the extack, and if it didn't, set it. But that
is only done when the callee is not exactly known. (E.g. in case of a
notifier invocation.)

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>
2023-02-06 08:48:25 +00:00
Petr Machata
60977a0c63 net: bridge: Add extack to br_multicast_new_port_group()
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>
2023-02-06 08:48:25 +00:00
Petr Machata
c00041cf1c net: bridge: Set strict_start_type at two policies
Make any attributes newly-added to br_port_policy or vlan_tunnel_policy
parsed strictly, to prevent userspace from passing garbage. Note that this
patchset only touches the former policy. The latter was adjusted for
completeness' sake. There do not appear to be other _deprecated calls
with non-NULL policies.

Suggested-by: Ido Schimmel <idosch@nvidia.com>
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>
2023-02-06 08:48:25 +00:00
Jakub Kicinski
82b4a9412b Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
net/core/gro.c
  7d2c89b325 ("skb: Do mix page pool and page referenced frags in GRO")
  b1a78b9b98 ("net: add support for ipv4 big tcp")
https://lore.kernel.org/all/20230203094454.5766f160@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-02 14:49:55 -08:00
Leon Romanovsky
028fb19c6b netlink: provide an ability to set default extack message
In netdev common pattern, extack pointer is forwarded to the drivers
to be filled with error message. However, the caller can easily
overwrite the filled message.

Instead of adding multiple "if (!extack->_msg)" checks before any
NL_SET_ERR_MSG() call, which appears after call to the driver, let's
add new macro to common code.

[1] https://lore.kernel.org/all/Y9Irgrgf3uxOjwUm@unreal
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/6993fac557a40a1973dfa0095107c3d03d40bec1.1675171790.git.leon@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-01 21:04:09 -08:00
Xin Long
46abd17302 bridge: use skb_ip_totlen in br netfilter
These 3 places in bridge netfilter are called on RX path after GRO
and IPv4 TCP GSO packets may come through, so replace iph tot_len
accessing with skb_ip_totlen() in there.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-01 20:54:27 -08:00
Florian Westphal
2b272bb558 netfilter: br_netfilter: disable sabotage_in hook after first suppression
When using a xfrm interface in a bridged setup (the outgoing device is
bridged), the incoming packets in the xfrm interface are only tracked
in the outgoing direction.

$ brctl show
bridge name     interfaces
br_eth1         eth1

$ conntrack -L
tcp 115 SYN_SENT src=192... dst=192... [UNREPLIED] ...

If br_netfilter is enabled, the first (encrypted) packet is received onR
eth1, conntrack hooks are called from br_netfilter emulation which
allocates nf_bridge info for this skb.

If the packet is for local machine, skb gets passed up the ip stack.
The skb passes through ip prerouting a second time. br_netfilter
ip_sabotage_in supresses the re-invocation of the hooks.

After this, skb gets decrypted in xfrm layer and appears in
network stack a second time (after decryption).

Then, ip_sabotage_in is called again and suppresses netfilter
hook invocation, even though the bridge layer never called them
for the plaintext incarnation of the packet.

Free the bridge info after the first suppression to avoid this.

I was unable to figure out where the regression comes from, as far as i
can see br_netfilter always had this problem; i did not expect that skb
is looped again with different headers.

Fixes: c4b0e771f9 ("netfilter: avoid using skb->nf_bridge directly")
Reported-and-tested-by: Wolfgang Nothdurft <wolfgang@linogate.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-01-31 13:59:36 +01:00
Steven Rostedt (Google)
292a089d78 treewide: Convert del_timer*() to timer_shutdown*()
Due to several bugs caused by timers being re-armed after they are
shutdown and just before they are freed, a new state of timers was added
called "shutdown".  After a timer is set to this state, then it can no
longer be re-armed.

The following script was run to find all the trivial locations where
del_timer() or del_timer_sync() is called in the same function that the
object holding the timer is freed.  It also ignores any locations where
the timer->function is modified between the del_timer*() and the free(),
as that is not considered a "trivial" case.

This was created by using a coccinelle script and the following
commands:

    $ cat timer.cocci
    @@
    expression ptr, slab;
    identifier timer, rfield;
    @@
    (
    -       del_timer(&ptr->timer);
    +       timer_shutdown(&ptr->timer);
    |
    -       del_timer_sync(&ptr->timer);
    +       timer_shutdown_sync(&ptr->timer);
    )
      ... when strict
          when != ptr->timer
    (
            kfree_rcu(ptr, rfield);
    |
            kmem_cache_free(slab, ptr);
    |
            kfree(ptr);
    )

    $ spatch timer.cocci . > /tmp/t.patch
    $ patch -p1 < /tmp/t.patch

Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Pavel Machek <pavel@ucw.cz> [ LED ]
Acked-by: Kalle Valo <kvalo@kernel.org> [ wireless ]
Acked-by: Paolo Abeni <pabeni@redhat.com> [ networking ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-12-25 13:38:09 -08:00
Linus Torvalds
71a7507afb Driver Core changes for 6.2-rc1
Here is the set of driver core and kernfs changes for 6.2-rc1.
 
 The "big" change in here is the addition of a new macro,
 container_of_const() that will preserve the "const-ness" of a pointer
 passed into it.
 
 The "problem" of the current container_of() macro is that if you pass in
 a "const *", out of it can comes a non-const pointer unless you
 specifically ask for it.  For many usages, we want to preserve the
 "const" attribute by using the same call.  For a specific example, this
 series changes the kobj_to_dev() macro to use it, allowing it to be used
 no matter what the const value is.  This prevents every subsystem from
 having to declare 2 different individual macros (i.e.
 kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
 the const value at build time, which having 2 macros would not do
 either.
 
 The driver for all of this have been discussions with the Rust kernel
 developers as to how to properly mark driver core, and kobject, objects
 as being "non-mutable".  The changes to the kobject and driver core in
 this pull request are the result of that, as there are lots of paths
 where kobjects and device pointers are not modified at all, so marking
 them as "const" allows the compiler to enforce this.
 
 So, a nice side affect of the Rust development effort has been already
 to clean up the driver core code to be more obvious about object rules.
 
 All of this has been bike-shedded in quite a lot of detail on lkml with
 different names and implementations resulting in the tiny version we
 have in here, much better than my original proposal.  Lots of subsystem
 maintainers have acked the changes as well.
 
 Other than this change, included in here are smaller stuff like:
   - kernfs fixes and updates to handle lock contention better
   - vmlinux.lds.h fixes and updates
   - sysfs and debugfs documentation updates
   - device property updates
 
 All of these have been in the linux-next tree for quite a while with no
 problems, OTHER than some merge issues with other trees that should be
 obvious when you hit them (block tree deletes a driver that this tree
 modifies, iommufd tree modifies code that this tree also touches).  If
 there are merge problems with these trees, please let me know.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the set of driver core and kernfs changes for 6.2-rc1.

  The "big" change in here is the addition of a new macro,
  container_of_const() that will preserve the "const-ness" of a pointer
  passed into it.

  The "problem" of the current container_of() macro is that if you pass
  in a "const *", out of it can comes a non-const pointer unless you
  specifically ask for it. For many usages, we want to preserve the
  "const" attribute by using the same call. For a specific example, this
  series changes the kobj_to_dev() macro to use it, allowing it to be
  used no matter what the const value is. This prevents every subsystem
  from having to declare 2 different individual macros (i.e.
  kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
  the const value at build time, which having 2 macros would not do
  either.

  The driver for all of this have been discussions with the Rust kernel
  developers as to how to properly mark driver core, and kobject,
  objects as being "non-mutable". The changes to the kobject and driver
  core in this pull request are the result of that, as there are lots of
  paths where kobjects and device pointers are not modified at all, so
  marking them as "const" allows the compiler to enforce this.

  So, a nice side affect of the Rust development effort has been already
  to clean up the driver core code to be more obvious about object
  rules.

  All of this has been bike-shedded in quite a lot of detail on lkml
  with different names and implementations resulting in the tiny version
  we have in here, much better than my original proposal. Lots of
  subsystem maintainers have acked the changes as well.

  Other than this change, included in here are smaller stuff like:

   - kernfs fixes and updates to handle lock contention better

   - vmlinux.lds.h fixes and updates

   - sysfs and debugfs documentation updates

   - device property updates

  All of these have been in the linux-next tree for quite a while with
  no problems"

* tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits)
  device property: Fix documentation for fwnode_get_next_parent()
  firmware_loader: fix up to_fw_sysfs() to preserve const
  usb.h: take advantage of container_of_const()
  device.h: move kobj_to_dev() to use container_of_const()
  container_of: add container_of_const() that preserves const-ness of the pointer
  driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion.
  driver core: fix up missed scsi/cxlflash class.devnode() conversion.
  driver core: fix up some missing class.devnode() conversions.
  driver core: make struct class.devnode() take a const *
  driver core: make struct class.dev_uevent() take a const *
  cacheinfo: Remove of_node_put() for fw_token
  device property: Add a blank line in Kconfig of tests
  device property: Rename goto label to be more precise
  device property: Move PROPERTY_ENTRY_BOOL() a bit down
  device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*()
  kernfs: fix all kernel-doc warnings and multiple typos
  driver core: pass a const * into of_device_uevent()
  kobject: kset_uevent_ops: make name() callback take a const *
  kobject: kset_uevent_ops: make filter() callback take a const *
  kobject: make kobject_namespace take a const *
  ...
2022-12-16 03:54:54 -08:00
Ido Schimmel
61f2183512 bridge: mcast: Support replacement of MDB port group entries
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>
2022-12-12 15:33:37 -08:00
Ido Schimmel
1d7b66a7d9 bridge: mcast: Allow user space to specify MDB entry routing protocol
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>
2022-12-12 15:33:37 -08:00