Commit Graph

2603 Commits

Author SHA1 Message Date
Zhengchuan Liang 81af4137a3 net: bridge: use a stable FDB dst snapshot in RCU readers
[ Upstream commit df46016532 ]

Local FDB entries can be rewritten in place by `fdb_delete_local()`, which
updates `f->dst` to another port or to `NULL` while keeping the entry
alive. Several bridge RCU readers inspect `f->dst`, including
`br_fdb_fillbuf()` through the `brforward_read()` sysfs path.

These readers currently load `f->dst` multiple times and can therefore
observe inconsistent values across the check and later dereference.
In `br_fdb_fillbuf()`, this means a concurrent local-FDB update can change
`f->dst` after the NULL check and before the `port_no` dereference,
leading to a NULL-ptr-deref.

Fix this by taking a single `READ_ONCE()` snapshot of `f->dst` in each
affected RCU reader and using that snapshot for the rest of the access
sequence. Also publish the in-place `f->dst` updates in `fdb_delete_local()`
with `WRITE_ONCE()` so the readers and writer use matching access patterns.

Fixes: 960b589f86 ("bridge: Properly check if local fdb entry can be deleted in br_fdb_change_mac_address")
Cc: stable@kernel.org
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Co-developed-by: Yuan Tan <yuantan098@gmail.com>
Signed-off-by: Yuan Tan <yuantan098@gmail.com>
Suggested-by: Xin Liu <bird@lzu.edu.cn>
Tested-by: Ren Wei <enjou1224z@gmail.com>
Signed-off-by: Zhengchuan Liang <zcliangcn@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/6570fabb85ecadb8baaf019efe856f407711c7b9.1776043229.git.zcliangcn@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
[ kept `*idx < cb->args[2]` instead of `*idx < ctx->fdb_idx` ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07 06:09:46 +02:00
Yang Yang c49b9256bb bridge: br_nd_send: validate ND option lengths
commit 850837965a upstream.

br_nd_send() walks ND options according to option-provided lengths.
A malformed option can make the parser advance beyond the computed
option span or use a too-short source LLADDR option payload.

Validate option lengths against the remaining NS option area before
advancing, and only read source LLADDR when the option is large enough
for an Ethernet address.

Fixes: ed842faeb2 ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports")
Cc: stable@vger.kernel.org
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Tested-by: Ao Zhou <n05ec@lzu.edu.cn>
Co-developed-by: Yuan Tan <tanyuan98@outlook.com>
Signed-off-by: Yuan Tan <tanyuan98@outlook.com>
Suggested-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Yang Yang <n05ec@lzu.edu.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260326034441.2037420-3-n05ec@lzu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-11 14:24:46 +02:00
Yang Yang 2ba4caba42 bridge: br_nd_send: linearize skb before parsing ND options
[ Upstream commit a01aee7caf ]

br_nd_send() parses neighbour discovery options from ns->opt[] and
assumes that these options are in the linear part of request.

Its callers only guarantee that the ICMPv6 header and target address
are available, so the option area can still be non-linear. Parsing
ns->opt[] in that case can access data past the linear buffer.

Linearize request before option parsing and derive ns from the linear
network header.

Fixes: ed842faeb2 ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports")
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Tested-by: Ao Zhou <n05ec@lzu.edu.cn>
Co-developed-by: Yuan Tan <tanyuan98@outlook.com>
Signed-off-by: Yuan Tan <tanyuan98@outlook.com>
Suggested-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Yang Yang <n05ec@lzu.edu.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260326034441.2037420-2-n05ec@lzu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-11 14:24:32 +02:00
Hyunwoo Kim e89dbd2736 bridge: cfm: Fix race condition in peer_mep deletion
[ Upstream commit 3715a00855 ]

When a peer MEP is being deleted, cancel_delayed_work_sync() is called
on ccm_rx_dwork before freeing. However, br_cfm_frame_rx() runs in
softirq context under rcu_read_lock (without RTNL) and can re-schedule
ccm_rx_dwork via ccm_rx_timer_start() between cancel_delayed_work_sync()
returning and kfree_rcu() being called.

The following is a simple race scenario:

           cpu0                                     cpu1

mep_delete_implementation()
  cancel_delayed_work_sync(ccm_rx_dwork);
                                           br_cfm_frame_rx()
                                             // peer_mep still in hlist
                                             if (peer_mep->ccm_defect)
                                               ccm_rx_timer_start()
                                                 queue_delayed_work(ccm_rx_dwork)
  hlist_del_rcu(&peer_mep->head);
  kfree_rcu(peer_mep, rcu);
                                           ccm_rx_work_expired()
                                             // on freed peer_mep

To prevent this, cancel_delayed_work_sync() is replaced with
disable_delayed_work_sync() in both peer MEP deletion paths, so
that subsequent queue_delayed_work() calls from br_cfm_frame_rx()
are silently rejected.

The cc_peer_disable() helper retains cancel_delayed_work_sync()
because it is also used for the CC enable/disable toggle path where
the work must remain re-schedulable.

Fixes: dc32cbb3db ("bridge: cfm: Kernel space implementation of CFM. CCM frame RX added.")
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/abBgYT5K_FI9rD1a@v4bel
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-25 11:08:52 +01:00
Fernando Fernandez Mancera aa73deb3b6 net: bridge: fix nd_tbl NULL dereference when IPv6 is disabled
[ Upstream commit e5e8906305 ]

When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
initialized because inet6_init() exits before ndisc_init() is called
which initializes it. Then, if neigh_suppress is enabled and an ICMPv6
Neighbor Discovery packet reaches the bridge, br_do_suppress_nd() will
dereference ipv6_stub->nd_tbl which is NULL, passing it to
neigh_lookup(). This causes a kernel NULL pointer dereference.

 BUG: kernel NULL pointer dereference, address: 0000000000000268
 Oops: 0000 [#1] PREEMPT SMP NOPTI
 [...]
 RIP: 0010:neigh_lookup+0x16/0xe0
 [...]
 Call Trace:
  <IRQ>
  ? neigh_lookup+0x16/0xe0
  br_do_suppress_nd+0x160/0x290 [bridge]
  br_handle_frame_finish+0x500/0x620 [bridge]
  br_handle_frame+0x353/0x440 [bridge]
  __netif_receive_skb_core.constprop.0+0x298/0x1110
  __netif_receive_skb_one_core+0x3d/0xa0
  process_backlog+0xa0/0x140
  __napi_poll+0x2c/0x170
  net_rx_action+0x2c4/0x3a0
  handle_softirqs+0xd0/0x270
  do_softirq+0x3f/0x60

Fix this by replacing IS_ENABLED(IPV6) call with ipv6_mod_enabled() in
the callers. This is in essence disabling NS/NA suppression when IPv6 is
disabled.

Fixes: ed842faeb2 ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports")
Reported-by: Guruprasad C P <gurucp2005@gmail.com>
Closes: https://lore.kernel.org/netdev/CAHXs0ORzd62QOG-Fttqa2Cx_A_VFp=utE2H2VTX5nqfgs7LDxQ@mail.gmail.com/
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260304120357.9778-1-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-13 17:20:45 +01:00
Nikolay Aleksandrov 724a405ce0 net: bridge: mcast: always update mdb_n_entries for vlan contexts
[ Upstream commit 8b769e311a ]

syzbot triggered a warning[1] about the number of mdb entries in a context.
It turned out that there are multiple ways to trigger that warning today
(some got added during the years), the root cause of the problem is that
the increase is done conditionally, and over the years these different
conditions increased so there were new ways to trigger the warning, that is
to do a decrease which wasn't paired with a previous increase.

For example one way to trigger it is with flush:
 $ ip l add br0 up type bridge vlan_filtering 1 mcast_snooping 1
 $ ip l add dumdum up master br0 type dummy
 $ bridge mdb add dev br0 port dumdum grp 239.0.0.1 permanent vid 1
 $ ip link set dev br0 down
 $ ip link set dev br0 type bridge mcast_vlan_snooping 1
   ^^^^ this will enable snooping, but will not update mdb_n_entries
        because in __br_multicast_enable_port_ctx() we check !netif_running
 $ bridge mdb flush dev br0
   ^^^ this will trigger the warning because it will delete the pg which
       we added above, which will try to decrease mdb_n_entries

Fix the problem by removing the conditional increase and always keep the
count up-to-date while the vlan exists. In order to do that we have to
first initialize it on port-vlan context creation, and then always increase
or decrease the value regardless of mcast options. To keep the current
behaviour we have to enforce the mdb limit only if the context is port's or
if the port-vlan's mcast snooping is enabled.

[1]
 ------------[ cut here ]------------
 n == 0
 WARNING: net/bridge/br_multicast.c:718 at br_multicast_port_ngroups_dec_one net/bridge/br_multicast.c:718 [inline], CPU#0: syz.4.4607/22043
 WARNING: net/bridge/br_multicast.c:718 at br_multicast_port_ngroups_dec net/bridge/br_multicast.c:771 [inline], CPU#0: syz.4.4607/22043
 WARNING: net/bridge/br_multicast.c:718 at br_multicast_del_pg+0x1bbe/0x1e20 net/bridge/br_multicast.c:825, CPU#0: syz.4.4607/22043
 Modules linked in:
 CPU: 0 UID: 0 PID: 22043 Comm: syz.4.4607 Not tainted syzkaller #0 PREEMPT(full)
 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
 RIP: 0010:br_multicast_port_ngroups_dec_one net/bridge/br_multicast.c:718 [inline]
 RIP: 0010:br_multicast_port_ngroups_dec net/bridge/br_multicast.c:771 [inline]
 RIP: 0010:br_multicast_del_pg+0x1bbe/0x1e20 net/bridge/br_multicast.c:825
 Code: 41 5f 5d e9 04 7a 48 f7 e8 3f 73 5c f7 90 0f 0b 90 e9 cf fd ff ff e8 31 73 5c f7 90 0f 0b 90 e9 16 fd ff ff e8 23 73 5c f7 90 <0f> 0b 90 e9 60 fd ff ff e8 15 73 5c f7 eb 05 e8 0e 73 5c f7 48 8b
 RSP: 0018:ffffc9000c207220 EFLAGS: 00010293
 RAX: ffffffff8a68042d RBX: ffff88807c6f1800 RCX: ffff888066e90000
 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
 RBP: 0000000000000000 R08: ffff888066e90000 R09: 000000000000000c
 R10: 000000000000000c R11: 0000000000000000 R12: ffff8880303ef800
 R13: dffffc0000000000 R14: ffff888050eb11c4 R15: 1ffff1100a1d6238
 FS:  00007fa45921b6c0(0000) GS:ffff8881256f5000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fa4591f9ff8 CR3: 0000000081df2000 CR4: 00000000003526f0
 Call Trace:
  <TASK>
  br_mdb_flush_pgs net/bridge/br_mdb.c:1525 [inline]
  br_mdb_flush net/bridge/br_mdb.c:1544 [inline]
  br_mdb_del_bulk+0x5e2/0xb20 net/bridge/br_mdb.c:1561
  rtnl_mdb_del+0x48a/0x640 net/core/rtnetlink.c:-1
  rtnetlink_rcv_msg+0x77e/0xbe0 net/core/rtnetlink.c:6967
  netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
  netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
  netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
  netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
  sock_sendmsg_nosec net/socket.c:727 [inline]
  __sock_sendmsg net/socket.c:742 [inline]
  ____sys_sendmsg+0xa68/0xad0 net/socket.c:2592
  ___sys_sendmsg+0x2a5/0x360 net/socket.c:2646
  __sys_sendmsg net/socket.c:2678 [inline]
  __do_sys_sendmsg net/socket.c:2683 [inline]
  __se_sys_sendmsg net/socket.c:2681 [inline]
  __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
  entry_SYSCALL_64_after_hwframe+0x77/0x7f
 RIP: 0033:0x7fa45839aeb9
 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
 RSP: 002b:00007fa45921b028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 00007fa458615fa0 RCX: 00007fa45839aeb9
 RDX: 0000000000000000 RSI: 00002000000000c0 RDI: 0000000000000004
 RBP: 00007fa458408c1f R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007fa458616038 R14: 00007fa458615fa0 R15: 00007fff0b59fae8
 </TASK>

Fixes: b57e8d870d ("net: bridge: Maintain number of MDB entries in net_bridge_mcast_port")
Reported-by: syzbot+d5d1b7343531d17bd3c5@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/aYrWbRp83MQR1ife@debil/T/#t
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Link: https://patch.msgid.link/20260213070031.1400003-2-nikolay@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-04 07:20:37 -05:00
Daniel Gomez 3521db9fcb netfilter: replace -EEXIST with -EBUSY
[ Upstream commit 2bafeb8d2f ]

The -EEXIST error code is reserved by the module loading infrastructure
to indicate that a module is already loaded. When a module's init
function returns -EEXIST, userspace tools like kmod interpret this as
"module already loaded" and treat the operation as successful, returning
0 to the user even though the module initialization actually failed.

Replace -EEXIST with -EBUSY to ensure correct error reporting in the module
initialization path.

Affected modules:
  * ebtable_broute ebtable_filter ebtable_nat arptable_filter
  * ip6table_filter ip6table_mangle ip6table_nat ip6table_raw
  * ip6table_security iptable_filter iptable_mangle iptable_nat
  * iptable_raw iptable_security

Signed-off-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-11 13:40:21 +01:00
Martin Kaiser ce9f1bdd4b net: bridge: fix static key check
[ Upstream commit cc0cf10fda ]

Fix the check if netfilter's static keys are available. netfilter defines
and exports static keys if CONFIG_JUMP_LABEL is enabled. (HAVE_JUMP_LABEL
is never defined.)

Fixes: 971502d77f ("bridge: netfilter: unroll NF_HOOK helper in bridge input path")
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Reviewed-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260127101925.1754425-1-martin@kaiser.cx
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-06 16:55:42 +01:00
Ido Schimmel bdced577da bridge: mcast: Fix use-after-free during router port configuration
commit 7544f3f5b0 upstream.

The bridge maintains a global list of ports behind which a multicast
router resides. The list is consulted during forwarding to ensure
multicast packets are forwarded to these ports even if the ports are not
member in the matching MDB entry.

When per-VLAN multicast snooping is enabled, the per-port multicast
context is disabled on each port and the port is removed from the global
router port list:

 # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1
 # ip link add name dummy1 up master br1 type dummy
 # ip link set dev dummy1 type bridge_slave mcast_router 2
 $ bridge -d mdb show | grep router
 router ports on br1: dummy1
 # ip link set dev br1 type bridge mcast_vlan_snooping 1
 $ bridge -d mdb show | grep router

However, the port can be re-added to the global list even when per-VLAN
multicast snooping is enabled:

 # ip link set dev dummy1 type bridge_slave mcast_router 0
 # ip link set dev dummy1 type bridge_slave mcast_router 2
 $ bridge -d mdb show | grep router
 router ports on br1: dummy1

Since commit 4b30ae9adb ("net: bridge: mcast: re-implement
br_multicast_{enable, disable}_port functions"), when per-VLAN multicast
snooping is enabled, multicast disablement on a port will disable the
per-{port, VLAN} multicast contexts and not the per-port one. As a
result, a port will remain in the global router port list even after it
is deleted. This will lead to a use-after-free [1] when the list is
traversed (when adding a new port to the list, for example):

 # ip link del dev dummy1
 # ip link add name dummy2 up master br1 type dummy
 # ip link set dev dummy2 type bridge_slave mcast_router 2

Similarly, stale entries can also be found in the per-VLAN router port
list. When per-VLAN multicast snooping is disabled, the per-{port, VLAN}
contexts are disabled on each port and the port is removed from the
per-VLAN router port list:

 # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1 mcast_vlan_snooping 1
 # ip link add name dummy1 up master br1 type dummy
 # bridge vlan add vid 2 dev dummy1
 # bridge vlan global set vid 2 dev br1 mcast_snooping 1
 # bridge vlan set vid 2 dev dummy1 mcast_router 2
 $ bridge vlan global show dev br1 vid 2 | grep router
       router ports: dummy1
 # ip link set dev br1 type bridge mcast_vlan_snooping 0
 $ bridge vlan global show dev br1 vid 2 | grep router

However, the port can be re-added to the per-VLAN list even when
per-VLAN multicast snooping is disabled:

 # bridge vlan set vid 2 dev dummy1 mcast_router 0
 # bridge vlan set vid 2 dev dummy1 mcast_router 2
 $ bridge vlan global show dev br1 vid 2 | grep router
       router ports: dummy1

When the VLAN is deleted from the port, the per-{port, VLAN} multicast
context will not be disabled since multicast snooping is not enabled
on the VLAN. As a result, the port will remain in the per-VLAN router
port list even after it is no longer member in the VLAN. This will lead
to a use-after-free [2] when the list is traversed (when adding a new
port to the list, for example):

 # ip link add name dummy2 up master br1 type dummy
 # bridge vlan add vid 2 dev dummy2
 # bridge vlan del vid 2 dev dummy1
 # bridge vlan set vid 2 dev dummy2 mcast_router 2

Fix these issues by removing the port from the relevant (global or
per-VLAN) router port list in br_multicast_port_ctx_deinit(). The
function is invoked during port deletion with the per-port multicast
context and during VLAN deletion with the per-{port, VLAN} multicast
context.

Note that deleting the multicast router timer is not enough as it only
takes care of the temporary multicast router states (1 or 3) and not the
permanent one (2).

[1]
BUG: KASAN: slab-out-of-bounds in br_multicast_add_router.part.0+0x3f1/0x560
Write of size 8 at addr ffff888004a67328 by task ip/384
[...]
Call Trace:
 <TASK>
 dump_stack_lvl+0x6f/0xa0
 print_address_description.constprop.0+0x6f/0x350
 print_report+0x108/0x205
 kasan_report+0xdf/0x110
 br_multicast_add_router.part.0+0x3f1/0x560
 br_multicast_set_port_router+0x74e/0xac0
 br_setport+0xa55/0x1870
 br_port_slave_changelink+0x95/0x120
 __rtnl_newlink+0x5e8/0xa40
 rtnl_newlink+0x627/0xb00
 rtnetlink_rcv_msg+0x6fb/0xb70
 netlink_rcv_skb+0x11f/0x350
 netlink_unicast+0x426/0x710
 netlink_sendmsg+0x75a/0xc20
 __sock_sendmsg+0xc1/0x150
 ____sys_sendmsg+0x5aa/0x7b0
 ___sys_sendmsg+0xfc/0x180
 __sys_sendmsg+0x124/0x1c0
 do_syscall_64+0xbb/0x360
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

[2]
BUG: KASAN: slab-use-after-free in br_multicast_add_router.part.0+0x378/0x560
Read of size 8 at addr ffff888009f00840 by task bridge/391
[...]
Call Trace:
 <TASK>
 dump_stack_lvl+0x6f/0xa0
 print_address_description.constprop.0+0x6f/0x350
 print_report+0x108/0x205
 kasan_report+0xdf/0x110
 br_multicast_add_router.part.0+0x378/0x560
 br_multicast_set_port_router+0x6f9/0xac0
 br_vlan_process_options+0x8b6/0x1430
 br_vlan_rtm_process_one+0x605/0xa30
 br_vlan_rtm_process+0x396/0x4c0
 rtnetlink_rcv_msg+0x2f7/0xb70
 netlink_rcv_skb+0x11f/0x350
 netlink_unicast+0x426/0x710
 netlink_sendmsg+0x75a/0xc20
 __sock_sendmsg+0xc1/0x150
 ____sys_sendmsg+0x5aa/0x7b0
 ___sys_sendmsg+0xfc/0x180
 __sys_sendmsg+0x124/0x1c0
 do_syscall_64+0xbb/0x360
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

Fixes: 2796d846d7 ("net: bridge: vlan: convert mcast router global option to per-vlan entry")
Fixes: 4b30ae9adb ("net: bridge: mcast: re-implement br_multicast_{enable, disable}_port functions")
Reported-by: syzbot+7bfa4b72c6a5da128d32@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/684c18bd.a00a0220.279073.000b.GAE@google.com/T/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250619182228.1656906-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-23 11:18:42 +01:00
Eric Dumazet 6dabb5b89c net: bridge: annotate data-races around fdb->{updated,used}
[ Upstream commit b25a0b4a21 ]

fdb->updated and fdb->used are read and written locklessly.

Add READ_ONCE()/WRITE_ONCE() annotations.

Fixes: 31cbc39b63 ("net: bridge: add option to allow activity notifications for any fdb entries")
Reported-by: syzbot+bfab43087ad57222ce96@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/695e3d74.050a0220.1c677c.035f.GAE@google.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260108093806.834459-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-23 11:18:37 +01:00
Alexandre Knecht 269c9283ff bridge: fix C-VLAN preservation in 802.1ad vlan_tunnel egress
[ Upstream commit 3128df6be1 ]

When using an 802.1ad bridge with vlan_tunnel, the C-VLAN tag is
incorrectly stripped from frames during egress processing.

br_handle_egress_vlan_tunnel() uses skb_vlan_pop() to remove the S-VLAN
from hwaccel before VXLAN encapsulation. However, skb_vlan_pop() also
moves any "next" VLAN from the payload into hwaccel:

    /* move next vlan tag to hw accel tag */
    __skb_vlan_pop(skb, &vlan_tci);
    __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);

For QinQ frames where the C-VLAN sits in the payload, this moves it to
hwaccel where it gets lost during VXLAN encapsulation.

Fix by calling __vlan_hwaccel_clear_tag() directly, which clears only
the hwaccel S-VLAN and leaves the payload untouched.

This path is only taken when vlan_tunnel is enabled and tunnel_info
is configured, so 802.1Q bridges are unaffected.

Tested with 802.1ad bridge + VXLAN vlan_tunnel, verified C-VLAN
preserved in VXLAN payload via tcpdump.

Fixes: 11538d039a ("bridge: vlan dst_metadata hooks in ingress and egress paths")
Signed-off-by: Alexandre Knecht <knecht.alexandre@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20251228020057.2788865-1-knecht.alexandre@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:23 +01:00
Thadeu Lima de Souza Cascardo 4888e1dcc3 net: Remove RTNL dance for SIOCBRADDIF and SIOCBRDELIF.
commit ed3ba9b6e2 upstream.

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>
[cascardo: fixed conflict at dev_ifsioc]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11 15:25:21 +01:00
Bagas Sanjaya 18b6574d4c net: bridge: Describe @tunnel_hash member in net_bridge_vlan_group struct
[ Upstream commit f79f9b7ace ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-08 10:14:34 +01:00
Nikolay Aleksandrov 29d4429a99 net: bridge: fix MST static key usage
[ Upstream commit ee87c63f9b ]

As Ido pointed out, the static key usage in MST is buggy and should use
inc/dec instead of enable/disable because we can have multiple bridges
with MST enabled which means a single bridge can disable MST for all.
Use static_branch_inc/dec to avoid that. When destroying a bridge decrement
the key if MST was enabled.

Fixes: ec7328b591 ("net: bridge: mst: Multiple Spanning Tree (MST) mode")
Reported-by: Ido Schimmel <idosch@nvidia.com>
Closes: https://lore.kernel.org/netdev/20251104120313.1306566-1-razor@blackwall.org/T/#m6888d87658f94ed1725433940f4f4ebb00b5a68b
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20251105111919.1499702-3-razor@blackwall.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-13 15:34:39 -05:00
Nikolay Aleksandrov bf3843183b net: bridge: fix use-after-free due to MST port state bypass
[ Upstream commit 8dca36978a ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-13 15:34:39 -05:00
Petr Machata 50952c6c3c net: bridge: Install FDB for bridge MAC on VLAN 0
[ Upstream commit cd9a9562b2 ]

Currently, after the bridge is created, the FDB does not hold an FDB entry
for the bridge MAC on VLAN 0:

 # ip link add name br up type bridge
 # ip -br link show dev br
 br               UNKNOWN        92:19:8c:4e:01:ed <BROADCAST,MULTICAST,UP,LOWER_UP>
 # bridge fdb show | grep 92:19:8c:4e:01:ed
 92:19:8c:4e:01:ed dev br vlan 1 master br permanent

Later when the bridge MAC is changed, or in fact when the address is given
during netdevice creation, the entry appears:

 # ip link add name br up address 00:11:22:33:44:55 type bridge
 # bridge fdb show | grep 00:11:22:33:44:55
 00:11:22:33:44:55 dev br vlan 1 master br permanent
 00:11:22:33:44:55 dev br master br permanent

However when the bridge address is set by the user to the current bridge
address before the first port is enslaved, none of the address handlers
gets invoked, because the address is not actually changed. The address is
however marked as NET_ADDR_SET. Then when a port is enslaved, the address
is not changed, because it is NET_ADDR_SET. Thus the VLAN 0 entry is not
added, and it has not been added previously either:

 # ip link add name br up type bridge
 # ip -br link show dev br
 br               UNKNOWN        7e:f0:a8:1a:be:c2 <BROADCAST,MULTICAST,UP,LOWER_UP>
 # ip link set dev br addr 7e:f0:a8:1a:be:c2
 # ip link add name v up type veth
 # ip link set dev v master br
 # ip -br link show dev br
 br               UNKNOWN        7e:f0:a8:1a:be:c2 <BROADCAST,MULTICAST,UP,LOWER_UP>
 # bridge fdb | grep 7e:f0:a8:1a:be:c2
 7e:f0:a8:1a:be:c2 dev br vlan 1 master br permanent

Then when the bridge MAC is used as DMAC, and br_handle_frame_finish()
looks up an FDB entry with VLAN=0, it doesn't find any, and floods the
traffic instead of passing it up.

Fix this by simply adding the VLAN 0 FDB entry for the bridge itself always
on netdevice creation. This also makes the behavior consistent with how
ports are treated: ports always have an FDB entry for each member VLAN as
well as VLAN 0.

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/415202b2d1b9b0899479a502bbe2ba188678f192.1758550408.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-13 15:34:29 -05:00
Ido Schimmel d7e41e51c4 bridge: Redirect to backup port when port is administratively down
[ Upstream commit 3d05b24429 ]

If a backup port is configured for a bridge port, the bridge will
redirect known unicast traffic towards the backup port when the primary
port is administratively up but without a carrier. This is useful, for
example, in MLAG configurations where a system is connected to two
switches and there is a peer link between both switches. The peer link
serves as the backup port in case one of the switches loses its
connection to the multi-homed system.

In order to avoid flooding when the primary port loses its carrier, the
bridge does not flush dynamic FDB entries pointing to the port upon STP
disablement, if the port has a backup port.

The above means that known unicast traffic destined to the primary port
will be blackholed when the port is put administratively down, until the
FDB entries pointing to it are aged-out.

Given that the current behavior is quite weird and unlikely to be
depended on by anyone, amend the bridge to redirect to the backup port
also when the primary port is administratively down and not only when it
does not have a carrier.

The change is motivated by a report from a user who expected traffic to
be redirected to the backup port when the primary port was put
administratively down while debugging a network issue.

Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250812080213.325298-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-13 15:34:12 -05:00
Eric Woudstra dae85dc6ad bridge: br_vlan_fill_forward_path_pvid: use br_vlan_group_rcu()
[ Upstream commit bbf0c98b3a ]

net/bridge/br_private.h:1627 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
7 locks held by socat/410:
 #0: ffff88800d7a9c90 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_stream_connect+0x43/0xa0
 #1: ffffffff9a779900 (rcu_read_lock){....}-{1:3}, at: __ip_queue_xmit+0x62/0x1830
 [..]
 #6: ffffffff9a779900 (rcu_read_lock){....}-{1:3}, at: nf_hook.constprop.0+0x8a/0x440

Call Trace:
 lockdep_rcu_suspicious.cold+0x4f/0xb1
 br_vlan_fill_forward_path_pvid+0x32c/0x410 [bridge]
 br_fill_forward_path+0x7a/0x4d0 [bridge]

Use to correct helper, non _rcu variant requires RTNL mutex.

Fixes: bcf2766b13 ("net: bridge: resolve forwarding path for VLAN tag actions in bridge devices")
Signed-off-by: Eric Woudstra <ericwouds@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-19 16:33:42 +02:00
Petr Machata 40600cddf4 net: bridge: Bounce invalid boolopts
[ Upstream commit 8625f5748f ]

The bridge driver currently tolerates options that it does not recognize.
Instead, it should bounce them.

Fixes: a428afe82f ("net: bridge: add support for user-controlled bool options")
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/e6fdca3b5a8d54183fbda075daffef38bdd7ddce.1757070067.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-09-19 16:35:48 +02:00
Wang Liang c47ca77fee netfilter: br_netfilter: do not check confirmed bit in br_nf_local_in() after confirm
[ Upstream commit 479a54ab92 ]

When send a broadcast packet to a tap device, which was added to a bridge,
br_nf_local_in() is called to confirm the conntrack. If another conntrack
with the same hash value is added to the hash table, which can be
triggered by a normal packet to a non-bridge device, the below warning
may happen.

  ------------[ cut here ]------------
  WARNING: CPU: 1 PID: 96 at net/bridge/br_netfilter_hooks.c:632 br_nf_local_in+0x168/0x200
  CPU: 1 UID: 0 PID: 96 Comm: tap_send Not tainted 6.17.0-rc2-dirty #44 PREEMPT(voluntary)
  RIP: 0010:br_nf_local_in+0x168/0x200
  Call Trace:
   <TASK>
   nf_hook_slow+0x3e/0xf0
   br_pass_frame_up+0x103/0x180
   br_handle_frame_finish+0x2de/0x5b0
   br_nf_hook_thresh+0xc0/0x120
   br_nf_pre_routing_finish+0x168/0x3a0
   br_nf_pre_routing+0x237/0x5e0
   br_handle_frame+0x1ec/0x3c0
   __netif_receive_skb_core+0x225/0x1210
   __netif_receive_skb_one_core+0x37/0xa0
   netif_receive_skb+0x36/0x160
   tun_get_user+0xa54/0x10c0
   tun_chr_write_iter+0x65/0xb0
   vfs_write+0x305/0x410
   ksys_write+0x60/0xd0
   do_syscall_64+0xa4/0x260
   entry_SYSCALL_64_after_hwframe+0x77/0x7f
   </TASK>
  ---[ end trace 0000000000000000 ]---

To solve the hash conflict, nf_ct_resolve_clash() try to merge the
conntracks, and update skb->_nfct. However, br_nf_local_in() still use the
old ct from local variable 'nfct' after confirm(), which leads to this
warning.

If confirm() does not insert the conntrack entry and return NF_DROP, the
warning may also occur. There is no need to reserve the WARN_ON_ONCE, just
remove it.

Link: https://lore.kernel.org/netdev/20250820043329.2902014-1-wangliang74@huawei.com/
Fixes: 62e7151ae3 ("netfilter: bridge: confirm multicast packets before passing them up the stack")
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Wang Liang <wangliang74@huawei.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-09-09 18:58:06 +02:00
Wang Liang bdb19cd0de net: bridge: fix soft lockup in br_multicast_query_expired()
[ Upstream commit d1547bf460 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-28 16:31:12 +02:00
Joseph Huang 71f435f846 net: bridge: Do not offload IGMP/MLD messages
[ Upstream commit 683dc24da8 ]

Do not offload IGMP/MLD messages as it could lead to IGMP/MLD Reports
being unintentionally flooded to Hosts. Instead, let the bridge decide
where to send these IGMP/MLD messages.

Consider the case where the local host is sending out reports in response
to a remote querier like the following:

       mcast-listener-process (IP_ADD_MEMBERSHIP)
          \
          br0
         /   \
      swp1   swp2
        |     |
  QUERIER     SOME-OTHER-HOST

In the above setup, br0 will want to br_forward() reports for
mcast-listener-process's group(s) via swp1 to QUERIER; but since the
source hwdom is 0, the report is eligible for tx offloading, and is
flooded by hardware to both swp1 and swp2, reaching SOME-OTHER-HOST as
well. (Example and illustration provided by Tobias.)

Fixes: 472111920f ("net: bridge: switchdev: allow the TX data plane forwarding to be offloaded")
Signed-off-by: Joseph Huang <Joseph.Huang@garmin.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250716153551.1830255-1-Joseph.Huang@garmin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-24 08:56:35 +02:00
Yong Wang 78f768e36c net: bridge: mcast: re-implement br_multicast_{enable, disable}_port functions
[ Upstream commit 4b30ae9adb ]

When a bridge port STP state is changed from BLOCKING/DISABLED to
FORWARDING, the port's igmp query timer will NOT re-arm itself if the
bridge has been configured as per-VLAN multicast snooping.

Solve this by choosing the correct multicast context(s) to enable/disable
port multicast based on whether per-VLAN multicast snooping is enabled or
not, i.e. using per-{port, VLAN} context in case of per-VLAN multicast
snooping by re-implementing br_multicast_enable_port() and
br_multicast_disable_port() functions.

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
 # bridge link set dev swp1 state 0
 # 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 link set 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
 # bridge link set dev swp1 state 0
 # 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 link set 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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-27 11:11:33 +01:00
Yong Wang 23d336e8a2 net: bridge: mcast: update multicast contex when vlan state is changed
[ Upstream commit 6c131043ea ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-27 11:11:33 +01:00
Huajian Yang de6edd3237 netfilter: bridge: Move specific fragmented packet to slow_path instead of dropping it
[ Upstream commit aa04c6f45b ]

The config NF_CONNTRACK_BRIDGE will change the bridge forwarding for
fragmented packets.

The original bridge does not know that it is a fragmented packet and
forwards it directly, after NF_CONNTRACK_BRIDGE is enabled, function
nf_br_ip_fragment and br_ip6_fragment will check the headroom.

In original br_forward, insufficient headroom of skb may indeed exist,
but there's still a way to save the skb in the device driver after
dev_queue_xmit.So droping the skb will change the original bridge
forwarding in some cases.

Fixes: 3c171f496e ("netfilter: bridge: add connection tracking system")
Signed-off-by: Huajian Yang <huajianyang@asrmicro.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:31:46 +02:00
Ido Schimmel 233a227a31 bridge: netfilter: Fix forwarding of fragmented packets
[ Upstream commit 91b6dbced0 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29 11:03:16 +02:00
Petr Machata 58cdd1ee65 bridge: mdb: Allow replace of a host-joined group
[ Upstream commit d9e9f6d7b7 ]

Attempts to replace an MDB group membership of the host itself are
currently bounced:

 # ip link add name br up type bridge vlan_filtering 1
 # bridge mdb replace dev br port br grp 239.0.0.1 vid 2
 # bridge mdb replace dev br port br grp 239.0.0.1 vid 2
 Error: bridge: Group is already joined by host.

A similar operation done on a member port would succeed. Ignore the check
for replacement of host group memberships as well.

The bit of code that this enables is br_multicast_host_join(), which, for
already-joined groups only refreshes the MC group expiration timer, which
is desirable; and a userspace notification, also desirable.

Change a selftest that exercises this code path from expecting a rejection
to expecting a pass. The rest of MDB selftests pass without modification.

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/e5c5188b9787ae806609e7ca3aa2a0a501b9b5c4.1738685648.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29 11:03:01 +02:00
Jonas Gorski d9ecaee617 net: bridge: switchdev: do not notify new brentries as changed
[ Upstream commit eb25de13bd ]

When adding a bridge vlan that is pvid or untagged after the vlan has
already been added to any other switchdev backed port, the vlan change
will be propagated as changed, since the flags change.

This causes the vlan to not be added to the hardware for DSA switches,
since the DSA handler ignores any vlans for the CPU or DSA ports that
are changed.

E.g. the following order of operations would work:

$ ip link add swbridge type bridge vlan_filtering 1 vlan_default_pvid 0
$ ip link set lan1 master swbridge
$ bridge vlan add dev swbridge vid 1 pvid untagged self
$ bridge vlan add dev lan1 vid 1 pvid untagged

but this order would break:

$ ip link add swbridge type bridge vlan_filtering 1 vlan_default_pvid 0
$ ip link set lan1 master swbridge
$ bridge vlan add dev lan1 vid 1 pvid untagged
$ bridge vlan add dev swbridge vid 1 pvid untagged self

Additionally, the vlan on the bridge itself would become undeletable:

$ bridge vlan
port              vlan-id
lan1              1 PVID Egress Untagged
swbridge          1 PVID Egress Untagged
$ bridge vlan del dev swbridge vid 1 self
$ bridge vlan
port              vlan-id
lan1              1 PVID Egress Untagged
swbridge          1 Egress Untagged

since the vlan was never added to DSA's vlan list, so deleting it will
cause an error, causing the bridge code to not remove it.

Fix this by checking if flags changed only for vlans that are already
brentry and pass changed as false for those that become brentries, as
these are a new vlan (member) from the switchdev point of view.

Since *changed is set to true for becomes_brentry = true regardless of
would_change's value, this will not change any rtnetlink notification
delivery, just the value passed on to switchdev in vlan->changed.

Fixes: 8d23a54f5b ("net: bridge: switchdev: differentiate new VLANs from changed ones")
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250414200020.192715-1-jonas.gorski@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-25 10:47:45 +02:00
Guillaume Nault 97c455c3c2 ipv4: Convert ip_route_input() to dscp_t.
[ Upstream commit 7e863e5db6 ]

Pass a dscp_t variable to ip_route_input(), instead of a plain u8, to
prevent accidental setting of ECN bits in ->flowi4_tos.

Callers of ip_route_input() to consider are:

  * input_action_end_dx4_finish() and input_action_end_dt4() in
    net/ipv6/seg6_local.c. These functions set the tos parameter to 0,
    which is already a valid dscp_t value, so they don't need to be
    adjusted for the new prototype.

  * icmp_route_lookup(), which already has a dscp_t variable to pass as
    parameter. We just need to remove the inet_dscp_to_dsfield()
    conversion.

  * br_nf_pre_routing_finish(), ip_options_rcv_srr() and ip4ip6_err(),
    which get the DSCP directly from IPv4 headers. Define a helper to
    read the .tos field of struct iphdr as dscp_t, so that these
    function don't have to do the conversion manually.

While there, declare *iph as const in br_nf_pre_routing_finish(),
declare its local variables in reverse-christmas-tree order and move
the "err = ip_route_input()" assignment out of the conditional to avoid
checkpatch warning.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/e9d40781d64d3d69f4c79ac8a008b8d67a033e8d.1727807926.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 27843ce6ba ("ipvlan: ensure network headers are in skb linear part")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-07 18:25:29 +01:00
Kuniyuki Iwashima cba5e43b0b bridge: Handle error of rtnl_register_module().
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>
2024-10-10 15:39:35 +02:00
Andy Roulin f9ff7665cd netfilter: br_netfilter: fix panic with metadata_dst skb
Fix a kernel panic in the br_netfilter module when sending untagged
traffic via a VxLAN device.
This happens during the check for fragmentation in br_nf_dev_queue_xmit.

It is dependent on:
1) the br_netfilter module being loaded;
2) net.bridge.bridge-nf-call-iptables set to 1;
3) a bridge with a VxLAN (single-vxlan-device) netdevice as a bridge port;
4) untagged frames with size higher than the VxLAN MTU forwarded/flooded

When forwarding the untagged packet to the VxLAN bridge port, before
the netfilter hooks are called, br_handle_egress_vlan_tunnel is called and
changes the skb_dst to the tunnel dst. The tunnel_dst is a metadata type
of dst, i.e., skb_valid_dst(skb) is false, and metadata->dst.dev is NULL.

Then in the br_netfilter hooks, in br_nf_dev_queue_xmit, there's a check
for frames that needs to be fragmented: frames with higher MTU than the
VxLAN device end up calling br_nf_ip_fragment, which in turns call
ip_skb_dst_mtu.

The ip_dst_mtu tries to use the skb_dst(skb) as if it was a valid dst
with valid dst->dev, thus the crash.

This case was never supported in the first place, so drop the packet
instead.

PING 10.0.0.2 (10.0.0.2) from 0.0.0.0 h1-eth0: 2000(2028) bytes of data.
[  176.291791] Unable to handle kernel NULL pointer dereference at
virtual address 0000000000000110
[  176.292101] Mem abort info:
[  176.292184]   ESR = 0x0000000096000004
[  176.292322]   EC = 0x25: DABT (current EL), IL = 32 bits
[  176.292530]   SET = 0, FnV = 0
[  176.292709]   EA = 0, S1PTW = 0
[  176.292862]   FSC = 0x04: level 0 translation fault
[  176.293013] Data abort info:
[  176.293104]   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[  176.293488]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[  176.293787]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[  176.293995] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000043ef5000
[  176.294166] [0000000000000110] pgd=0000000000000000,
p4d=0000000000000000
[  176.294827] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[  176.295252] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel veth
br_netfilter bridge stp llc ipv6 crct10dif_ce
[  176.295923] CPU: 0 PID: 188 Comm: ping Not tainted
6.8.0-rc3-g5b3fbd61b9d1 #2
[  176.296314] Hardware name: linux,dummy-virt (DT)
[  176.296535] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS
BTYPE=--)
[  176.296808] pc : br_nf_dev_queue_xmit+0x390/0x4ec [br_netfilter]
[  176.297382] lr : br_nf_dev_queue_xmit+0x2ac/0x4ec [br_netfilter]
[  176.297636] sp : ffff800080003630
[  176.297743] x29: ffff800080003630 x28: 0000000000000008 x27:
ffff6828c49ad9f8
[  176.298093] x26: ffff6828c49ad000 x25: 0000000000000000 x24:
00000000000003e8
[  176.298430] x23: 0000000000000000 x22: ffff6828c4960b40 x21:
ffff6828c3b16d28
[  176.298652] x20: ffff6828c3167048 x19: ffff6828c3b16d00 x18:
0000000000000014
[  176.298926] x17: ffffb0476322f000 x16: ffffb7e164023730 x15:
0000000095744632
[  176.299296] x14: ffff6828c3f1c880 x13: 0000000000000002 x12:
ffffb7e137926a70
[  176.299574] x11: 0000000000000001 x10: ffff6828c3f1c898 x9 :
0000000000000000
[  176.300049] x8 : ffff6828c49bf070 x7 : 0008460f18d5f20e x6 :
f20e0100bebafeca
[  176.300302] x5 : ffff6828c7f918fe x4 : ffff6828c49bf070 x3 :
0000000000000000
[  176.300586] x2 : 0000000000000000 x1 : ffff6828c3c7ad00 x0 :
ffff6828c7f918f0
[  176.300889] Call trace:
[  176.301123]  br_nf_dev_queue_xmit+0x390/0x4ec [br_netfilter]
[  176.301411]  br_nf_post_routing+0x2a8/0x3e4 [br_netfilter]
[  176.301703]  nf_hook_slow+0x48/0x124
[  176.302060]  br_forward_finish+0xc8/0xe8 [bridge]
[  176.302371]  br_nf_hook_thresh+0x124/0x134 [br_netfilter]
[  176.302605]  br_nf_forward_finish+0x118/0x22c [br_netfilter]
[  176.302824]  br_nf_forward_ip.part.0+0x264/0x290 [br_netfilter]
[  176.303136]  br_nf_forward+0x2b8/0x4e0 [br_netfilter]
[  176.303359]  nf_hook_slow+0x48/0x124
[  176.303803]  __br_forward+0xc4/0x194 [bridge]
[  176.304013]  br_flood+0xd4/0x168 [bridge]
[  176.304300]  br_handle_frame_finish+0x1d4/0x5c4 [bridge]
[  176.304536]  br_nf_hook_thresh+0x124/0x134 [br_netfilter]
[  176.304978]  br_nf_pre_routing_finish+0x29c/0x494 [br_netfilter]
[  176.305188]  br_nf_pre_routing+0x250/0x524 [br_netfilter]
[  176.305428]  br_handle_frame+0x244/0x3cc [bridge]
[  176.305695]  __netif_receive_skb_core.constprop.0+0x33c/0xecc
[  176.306080]  __netif_receive_skb_one_core+0x40/0x8c
[  176.306197]  __netif_receive_skb+0x18/0x64
[  176.306369]  process_backlog+0x80/0x124
[  176.306540]  __napi_poll+0x38/0x17c
[  176.306636]  net_rx_action+0x124/0x26c
[  176.306758]  __do_softirq+0x100/0x26c
[  176.307051]  ____do_softirq+0x10/0x1c
[  176.307162]  call_on_irq_stack+0x24/0x4c
[  176.307289]  do_softirq_own_stack+0x1c/0x2c
[  176.307396]  do_softirq+0x54/0x6c
[  176.307485]  __local_bh_enable_ip+0x8c/0x98
[  176.307637]  __dev_queue_xmit+0x22c/0xd28
[  176.307775]  neigh_resolve_output+0xf4/0x1a0
[  176.308018]  ip_finish_output2+0x1c8/0x628
[  176.308137]  ip_do_fragment+0x5b4/0x658
[  176.308279]  ip_fragment.constprop.0+0x48/0xec
[  176.308420]  __ip_finish_output+0xa4/0x254
[  176.308593]  ip_finish_output+0x34/0x130
[  176.308814]  ip_output+0x6c/0x108
[  176.308929]  ip_send_skb+0x50/0xf0
[  176.309095]  ip_push_pending_frames+0x30/0x54
[  176.309254]  raw_sendmsg+0x758/0xaec
[  176.309568]  inet_sendmsg+0x44/0x70
[  176.309667]  __sys_sendto+0x110/0x178
[  176.309758]  __arm64_sys_sendto+0x28/0x38
[  176.309918]  invoke_syscall+0x48/0x110
[  176.310211]  el0_svc_common.constprop.0+0x40/0xe0
[  176.310353]  do_el0_svc+0x1c/0x28
[  176.310434]  el0_svc+0x34/0xb4
[  176.310551]  el0t_64_sync_handler+0x120/0x12c
[  176.310690]  el0t_64_sync+0x190/0x194
[  176.311066] Code: f9402e61 79402aa2 927ff821 f9400023 (f9408860)
[  176.315743] ---[ end trace 0000000000000000 ]---
[  176.316060] Kernel panic - not syncing: Oops: Fatal exception in
interrupt
[  176.316371] Kernel Offset: 0x37e0e3000000 from 0xffff800080000000
[  176.316564] PHYS_OFFSET: 0xffff97d780000000
[  176.316782] CPU features: 0x0,88000203,3c020000,0100421b
[  176.317210] Memory Limit: none
[  176.317527] ---[ end Kernel panic - not syncing: Oops: Fatal
Exception in interrupt ]---\

Fixes: 11538d039a ("bridge: vlan dst_metadata hooks in ingress and egress paths")
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Andy Roulin <aroulin@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20241001154400.22787-2-aroulin@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-04 11:54:52 -07:00
Linus Torvalds 8c245fe7dd Merge tag 'net-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Paolo Abeni:
 "Including fixes from ieee802154, bluetooth and netfilter.

  Current release - regressions:

   - eth: mlx5: fix wrong reserved field in hca_cap_2 in mlx5_ifc

   - eth: am65-cpsw: fix forever loop in cleanup code

  Current release - new code bugs:

   - eth: mlx5: HWS, fixed double-free in error flow of creating SQ

  Previous releases - regressions:

   - core: avoid potential underflow in qdisc_pkt_len_init() with UFO

   - core: test for not too small csum_start in virtio_net_hdr_to_skb()

   - vrf: revert "vrf: remove unnecessary RCU-bh critical section"

   - bluetooth:
       - fix uaf in l2cap_connect
       - fix possible crash on mgmt_index_removed

   - dsa: improve shutdown sequence

   - eth: mlx5e: SHAMPO, fix overflow of hd_per_wq

   - eth: ip_gre: fix drops of small packets in ipgre_xmit

  Previous releases - always broken:

   - core: fix gso_features_check to check for both
     dev->gso_{ipv4_,}max_size

   - core: fix tcp fraglist segmentation after pull from frag_list

   - netfilter: nf_tables: prevent nf_skb_duplicated corruption

   - sctp: set sk_state back to CLOSED if autobind fails in
     sctp_listen_start

   - mac802154: fix potential RCU dereference issue in
     mac802154_scan_worker

   - eth: fec: restart PPS after link state change"

* tag 'net-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (48 commits)
  sctp: set sk_state back to CLOSED if autobind fails in sctp_listen_start
  dt-bindings: net: xlnx,axi-ethernet: Add missing reg minItems
  doc: net: napi: Update documentation for napi_schedule_irqoff
  net/ncsi: Disable the ncsi work before freeing the associated structure
  net: phy: qt2025: Fix warning: unused import DeviceId
  gso: fix udp gso fraglist segmentation after pull from frag_list
  bridge: mcast: Fail MDB get request on empty entry
  vrf: revert "vrf: Remove unnecessary RCU-bh critical section"
  net: ethernet: ti: am65-cpsw: Fix forever loop in cleanup code
  net: phy: realtek: Check the index value in led_hw_control_get
  ppp: do not assume bh is held in ppp_channel_bridge_input()
  selftests: rds: move include.sh to TEST_FILES
  net: test for not too small csum_start in virtio_net_hdr_to_skb()
  net: gso: fix tcp fraglist segmentation after pull from frag_list
  ipv4: ip_gre: Fix drops of small packets in ipgre_xmit
  net: stmmac: dwmac4: extend timeout for VLAN Tag register busy bit check
  net: add more sanity checks to qdisc_pkt_len_init()
  net: avoid potential underflow in qdisc_pkt_len_init() with UFO
  net: ethernet: ti: cpsw_ale: Fix warning on some platforms
  net: microchip: Make FDMA config symbol invisible
  ...
2024-10-03 09:44:00 -07:00
Ido Schimmel 555f45d24b bridge: mcast: Fail MDB get request on empty entry
When user space deletes a port from an MDB entry, the port is removed
synchronously. If this was the last port in the entry and the entry is
not joined by the host itself, then the entry is scheduled for deletion
via a timer.

The above means that it is possible for the MDB get netlink request to
retrieve an empty entry which is scheduled for deletion. This is
problematic as after deleting the last port in an entry, user space
cannot rely on a non-zero return code from the MDB get request as an
indication that the port was successfully removed.

Fix by returning an error when the entry's port list is empty and the
entry is not joined by the host.

Fixes: 68b380a395 ("bridge: mcast: Add MDB get support")
Reported-by: Jamie Bainbridge <jamie.bainbridge@gmail.com>
Closes: https://lore.kernel.org/netdev/c92569919307749f879b9482b0f3e125b7d9d2e3.1726480066.git.jamie.bainbridge@gmail.com/
Tested-by: Jamie Bainbridge <jamie.bainbridge@gmail.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20240929123640.558525-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-02 17:26:57 -07:00
Al Viro 5f60d5f6bb move asm/unaligned.h to linux/unaligned.h
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.

auto-generated by the following:

for i in `git grep -l -w asm/unaligned.h`; do
	sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
	sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
2024-10-02 17:23:23 -04:00
Ido Schimmel 1f23a1909d netfilter: br_netfilter: Unmask upper DSCP bits in br_nf_pre_routing_finish()
Unmask upper DSCP bits when calling ip_route_output() so that in the
future it could perform the FIB lookup according to the full DSCP value.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-09-09 14:14:52 +01:00
Jakub Kicinski f723224742 Merge tag 'nf-next-24-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

Patch #1 adds ctnetlink support for kernel side filtering for
	 deletions, from Changliang Wu.

Patch #2 updates nft_counter support to Use u64_stats_t,
	 from Sebastian Andrzej Siewior.

Patch #3 uses kmemdup_array() in all xtables frontends,
	 from Yan Zhen.

Patch #4 is a oneliner to use ERR_CAST() in nf_conntrack instead
	 opencoded casting, from Shen Lichuan.

Patch #5 removes unused argument in nftables .validate interface,
	 from Florian Westphal.

Patch #6 is a oneliner to correct a typo in nftables kdoc,
	 from Simon Horman.

Patch #7 fixes missing kdoc in nftables, also from Simon.

Patch #8 updates nftables to handle timeout less than CONFIG_HZ.

Patch #9 rejects element expiration if timeout is zero,
	 otherwise it is silently ignored.

Patch #10 disallows element expiration larger than timeout.

Patch #11 removes unnecessary READ_ONCE annotation while mutex is held.

Patch #12 adds missing READ_ONCE/WRITE_ONCE annotation in dynset.

Patch #13 annotates data-races around element expiration.

Patch #14 allocates timeout and expiration in one single set element
	  extension, they are tighly couple, no reason to keep them
	  separated anymore.

Patch #15 updates nftables to interpret zero timeout element as never
	  times out. Note that it is already possible to declare sets
	  with elements that never time out but this generalizes to all
	  kind of set with timeouts.

Patch #16 supports for element timeout and expiration updates.

* tag 'nf-next-24-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: set element timeout update support
  netfilter: nf_tables: zero timeout means element never times out
  netfilter: nf_tables: consolidate timeout extension for elements
  netfilter: nf_tables: annotate data-races around element expiration
  netfilter: nft_dynset: annotate data-races around set timeout
  netfilter: nf_tables: remove annotation to access set timeout while holding lock
  netfilter: nf_tables: reject expiration higher than timeout
  netfilter: nf_tables: reject element expiration with no timeout
  netfilter: nf_tables: elements with timeout below CONFIG_HZ never expire
  netfilter: nf_tables: Add missing Kernel doc
  netfilter: nf_tables: Correct spelling in nf_tables.h
  netfilter: nf_tables: drop unused 3rd argument from validate callback ops
  netfilter: conntrack: Convert to use ERR_CAST()
  netfilter: Use kmemdup_array instead of kmemdup for multiple allocation
  netfilter: nft_counter: Use u64_stats_t for statistic.
  netfilter: ctnetlink: support CTA_FILTER for flush
====================

Link: https://patch.msgid.link/20240905232920.5481-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-06 18:39:31 -07:00
Jakub Kicinski 502cc061de Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/phy/phy_device.c
  2560db6ede ("net: phy: Fix missing of_node_put() for leds")
  1dce520abd ("net: phy: Use for_each_available_child_of_node_scoped()")
https://lore.kernel.org/20240904115823.74333648@canb.auug.org.au

Adjacent changes:

drivers/net/ethernet/xilinx/xilinx_axienet.h
drivers/net/ethernet/xilinx/xilinx_axienet_main.c
  858430db28 ("net: xilinx: axienet: Fix race in axienet_stop")
  76abb5d675 ("net: xilinx: axienet: Add statistics support")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-05 20:37:20 -07:00
Jonas Gorski bee2ef946d net: bridge: br_fdb_external_learn_add(): always set EXT_LEARN
When userspace wants to take over a fdb entry by setting it as
EXTERN_LEARNED, we set both flags BR_FDB_ADDED_BY_EXT_LEARN and
BR_FDB_ADDED_BY_USER in br_fdb_external_learn_add().

If the bridge updates the entry later because its port changed, we clear
the BR_FDB_ADDED_BY_EXT_LEARN flag, but leave the BR_FDB_ADDED_BY_USER
flag set.

If userspace then wants to take over the entry again,
br_fdb_external_learn_add() sees that BR_FDB_ADDED_BY_USER and skips
setting the BR_FDB_ADDED_BY_EXT_LEARN flags, thus silently ignores the
update.

Fix this by always allowing to set BR_FDB_ADDED_BY_EXT_LEARN regardless
if this was a user fdb entry or not.

Fixes: 710ae72877 ("net: bridge: Mark FDB entries that were added by user as such")
Signed-off-by: Jonas Gorski <jonas.gorski@bisdn.de>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20240903081958.29951-1-jonas.gorski@bisdn.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-04 16:36:21 -07:00
Alexander Lobakin 05c1280a2b netdev_features: convert NETIF_F_NETNS_LOCAL to dev->netns_local
"Interface can't change network namespaces" is rather an attribute,
not a feature, and it can't be changed via Ethtool.
Make it a "cold" private flag instead of a netdev_feature and free
one more bit.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-09-03 11:36:43 +02:00
Alexander Lobakin 00d066a4d4 netdev_features: convert NETIF_F_LLTX to dev->lltx
NETIF_F_LLTX can't be changed via Ethtool and is not a feature,
rather an attribute, very similar to IFF_NO_QUEUE (and hot).
Free one netdev_features_t bit and make it a "hot" private flag.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-09-03 11:36:43 +02:00
Florian Westphal eaf9b2c875 netfilter: nf_tables: drop unused 3rd argument from validate callback ops
Since commit a654de8fdc ("netfilter: nf_tables: fix chain dependency validation")
the validate() callback no longer needs the return pointer argument.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-09-03 10:47:17 +02:00
Yan Zhen 20eb5e7cb7 netfilter: Use kmemdup_array instead of kmemdup for multiple allocation
When we are allocating an array, using kmemdup_array() to take care about
multiplication and possible overflows.

Also it makes auditing the code easier.

Signed-off-by: Yan Zhen <yanzhen@vivo.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-09-03 10:47:16 +02:00
Florian Westphal 7ea0522ef8 netfilter: nf_tables: pass context structure to nft_parse_register_load
Mechanical transformation, no logical changes intended.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-08-20 12:37:24 +02:00
Florian Westphal 7d8dc1c7be netfilter: nf_queue: drop packets with cloned unconfirmed conntracks
Conntrack assumes an unconfirmed entry (not yet committed to global hash
table) has a refcount of 1 and is not visible to other cores.

With multicast forwarding this assumption breaks down because such
skbs get cloned after being picked up, i.e.  ct->use refcount is > 1.

Likewise, bridge netfilter will clone broad/mutlicast frames and
all frames in case they need to be flood-forwarded during learning
phase.

For ip multicast forwarding or plain bridge flood-forward this will
"work" because packets don't leave softirq and are implicitly
serialized.

With nfqueue this no longer holds true, the packets get queued
and can be reinjected in arbitrary ways.

Disable this feature, I see no other solution.

After this patch, nfqueue cannot queue packets except the last
multicast/broadcast packet.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-08-14 23:37:23 +02:00
Nikolay Aleksandrov 92c4ee2520 net: bridge: mcast: wait for previous gc cycles when removing port
syzbot hit a use-after-free[1] which is caused because the bridge doesn't
make sure that all previous garbage has been collected when removing a
port. What happens is:
      CPU 1                   CPU 2
 start gc cycle           remove port
                         acquire gc lock first
 wait for lock
                         call br_multicasg_gc() directly
 acquire lock now but    free port
 the port can be freed
 while grp timers still
 running

Make sure all previous gc cycles have finished by using flush_work before
freeing the port.

[1]
  BUG: KASAN: slab-use-after-free in br_multicast_port_group_expired+0x4c0/0x550 net/bridge/br_multicast.c:861
  Read of size 8 at addr ffff888071d6d000 by task syz.5.1232/9699

  CPU: 1 PID: 9699 Comm: syz.5.1232 Not tainted 6.10.0-rc5-syzkaller-00021-g24ca36a562d6 #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
  Call Trace:
   <IRQ>
   __dump_stack lib/dump_stack.c:88 [inline]
   dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
   print_address_description mm/kasan/report.c:377 [inline]
   print_report+0xc3/0x620 mm/kasan/report.c:488
   kasan_report+0xd9/0x110 mm/kasan/report.c:601
   br_multicast_port_group_expired+0x4c0/0x550 net/bridge/br_multicast.c:861
   call_timer_fn+0x1a3/0x610 kernel/time/timer.c:1792
   expire_timers kernel/time/timer.c:1843 [inline]
   __run_timers+0x74b/0xaf0 kernel/time/timer.c:2417
   __run_timer_base kernel/time/timer.c:2428 [inline]
   __run_timer_base kernel/time/timer.c:2421 [inline]
   run_timer_base+0x111/0x190 kernel/time/timer.c:2437

Reported-by: syzbot+263426984509be19c9a0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=263426984509be19c9a0
Fixes: e12cec65b5 ("net: bridge: mcast: destroy all entries via gc")
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20240802080730.3206303-1-razor@blackwall.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-05 16:33:56 -07:00
Joel Granados 78eb4ea25c sysctl: treewide: constify the ctl_table argument of proc_handlers
const qualify the struct ctl_table argument in the proc_handler function
signatures. This is a prerequisite to moving the static ctl_table
structs into .rodata data which will ensure that proc_handler function
pointers cannot be modified.

This patch has been generated by the following coccinelle script:

```
  virtual patch

  @r1@
  identifier ctl, write, buffer, lenp, ppos;
  identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)";
  @@

  int func(
  - struct ctl_table *ctl
  + const struct ctl_table *ctl
    ,int write, void *buffer, size_t *lenp, loff_t *ppos);

  @r2@
  identifier func, ctl, write, buffer, lenp, ppos;
  @@

  int func(
  - struct ctl_table *ctl
  + const struct ctl_table *ctl
    ,int write, void *buffer, size_t *lenp, loff_t *ppos)
  { ... }

  @r3@
  identifier func;
  @@

  int func(
  - struct ctl_table *
  + const struct ctl_table *
    ,int , void *, size_t *, loff_t *);

  @r4@
  identifier func, ctl;
  @@

  int func(
  - struct ctl_table *ctl
  + const struct ctl_table *ctl
    ,int , void *, size_t *, loff_t *);

  @r5@
  identifier func, write, buffer, lenp, ppos;
  @@

  int func(
  - struct ctl_table *
  + const struct ctl_table *
    ,int write, void *buffer, size_t *lenp, loff_t *ppos);

```

* Code formatting was adjusted in xfs_sysctl.c to comply with code
  conventions. The xfs_stats_clear_proc_handler,
  xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where
  adjusted.

* The ctl_table argument in proc_watchdog_common was const qualified.
  This is called from a proc_handler itself and is calling back into
  another proc_handler, making it necessary to change it as part of the
  proc_handler migration.

Co-developed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Co-developed-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Joel Granados <j.granados@samsung.com>
2024-07-24 20:59:29 +02:00
Jakub Kicinski 51b35d4f9d Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in late fixes to prepare for the 6.11 net-next PR.

Conflicts:
  93c3a96c30 ("net: pse-pd: Do not return EOPNOSUPP if config is null")
  4cddb0f15e ("net: ethtool: pse-pd: Fix possible null-deref")
  30d7b67277 ("net: ethtool: Add new power limit get and set features")
https://lore.kernel.org/20240715123204.623520bb@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-15 13:19:17 -07:00
Elliot Ayrey 0a1868b93f net: bridge: mst: Check vlan state for egress decision
If a port is blocking in the common instance but forwarding in an MST
instance, traffic egressing the bridge will be dropped because the
state of the common instance is overriding that of the MST instance.

Fix this by skipping the port state check in MST mode to allow
checking the vlan state via br_allowed_egress(). This is similar to
what happens in br_handle_frame_finish() when checking ingress
traffic, which was introduced in the change below.

Fixes: ec7328b591 ("net: bridge: mst: Multiple Spanning Tree (MST) mode")
Signed-off-by: Elliot Ayrey <elliot.ayrey@alliedtelesis.co.nz>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-07-15 13:40:28 +01:00
Sebastian Andrzej Siewior c67ef53a88 netfilter: br_netfilter: Use nested-BH locking for brnf_frag_data_storage.
brnf_frag_data_storage is a per-CPU variable and relies on disabled BH
for its locking. Without per-CPU locking in local_bh_disable() on
PREEMPT_RT this data structure requires explicit locking.

Add a local_lock_t to the data structure and use local_lock_nested_bh()
for locking. This change adds only lockdep coverage and does not alter
the functional behaviour for !PREEMPT_RT.

Cc: Florian Westphal <fw@strlen.de>
Cc: Jozsef Kadlecsik <kadlec@netfilter.org>
Cc: Nikolay Aleksandrov <razor@blackwall.org>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: bridge@lists.linux.dev
Cc: coreteam@netfilter.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20240620132727.660738-8-bigeasy@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-24 16:41:23 -07:00
Jakub Kicinski 4c7d3d79c7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

No conflicts, no adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-13 13:13:46 -07:00