linux-stable.git/net/bridge, branch v6.1.136 Linux kernel stable tree net: bridge: switchdev: do not notify new brentries as changed 2025-04-25T08:43:50+00:00 Jonas Gorski jonas.gorski@gmail.com 2025-04-14T20:00:20+00:00 f06b5b4225b869a881e930bf24303adefb98aa78 [ Upstream commit eb25de13bd9cf025413a04f25e715d0e99847e30 ] 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: 8d23a54f5bee ("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> 
[ Upstream commit eb25de13bd9cf025413a04f25e715d0e99847e30 ]

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: 8d23a54f5bee ("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>
ipv4: Convert ip_route_input() to dscp_t. 2025-03-07T15:56:44+00:00 Guillaume Nault gnault@redhat.com 2024-10-01T19:28:43+00:00 3e8520bca50199b3e5fcc4c569bb7b7033ba7d8a [ Upstream commit 7e863e5db6185b1add0df4cb01b31a4ed1c4b738 ] 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: 27843ce6ba3d ("ipvlan: ensure network headers are in skb linear part") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7e863e5db6185b1add0df4cb01b31a4ed1c4b738 ]

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: 27843ce6ba3d ("ipvlan: ensure network headers are in skb linear part")
Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: br_netfilter: fix panic with metadata_dst skb 2024-10-17T13:22:19+00:00 Andy Roulin aroulin@nvidia.com 2024-10-01T15:43:59+00:00 78ed917133b118661e1fe62d4a85d5d428ee9568 [ Upstream commit f9ff7665cd128012868098bbd07e28993e314fdb ] 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: 11538d039ac6 ("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> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit f9ff7665cd128012868098bbd07e28993e314fdb ]

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: 11538d039ac6 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: bridge: br_fdb_external_learn_add(): always set EXT_LEARN 2024-09-12T09:10:22+00:00 Jonas Gorski jonas.gorski@bisdn.de 2024-09-03T08:19:57+00:00 dc9dad0108f1daba0853c82e9962be62de4b21da [ Upstream commit bee2ef946d3184e99077be526567d791c473036f ] 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: 710ae7287737 ("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> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit bee2ef946d3184e99077be526567d791c473036f ]

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: 710ae7287737 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: nf_queue: drop packets with cloned unconfirmed conntracks 2024-08-29T15:30:25+00:00 Florian Westphal fw@strlen.de 2024-08-07T19:28:41+00:00 6dcc8ba8a6074bb79040f502dc66ad23a58a1c86 [ Upstream commit 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb ] 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: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb ]

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: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: bridge: mcast: wait for previous gc cycles when removing port 2024-08-14T11:52:43+00:00 Nikolay Aleksandrov razor@blackwall.org 2024-08-02T08:07:30+00:00 0d8b26e10e680c01522d7cc14abe04c3265a928f [ Upstream commit 92c4ee25208d0f35dafc3213cdf355fbe449e078 ] 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: e12cec65b554 ("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> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 92c4ee25208d0f35dafc3213cdf355fbe449e078 ]

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: e12cec65b554 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: bridge: mst: Check vlan state for egress decision 2024-08-03T06:49:09+00:00 Elliot Ayrey elliot.ayrey@alliedtelesis.co.nz 2024-07-12T01:31:33+00:00 0077b003e41e8f327568b53abca936ba895d1684 [ Upstream commit 0a1868b93fad5938dbcca77286b25bf211c49f7a ] 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: ec7328b59176 ("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> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 0a1868b93fad5938dbcca77286b25bf211c49f7a ]

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: ec7328b59176 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: bridge: mst: fix suspicious rcu usage in br_mst_set_state 2024-06-21T12:35:52+00:00 Nikolay Aleksandrov razor@blackwall.org 2024-06-09T10:36:54+00:00 caaa2129784a04dcade0ea92c12e6ff90bbd23d8 [ Upstream commit 546ceb1dfdac866648ec959cbc71d9525bd73462 ] I converted br_mst_set_state to RCU to avoid a vlan use-after-free but forgot to change the vlan group dereference helper. Switch to vlan group RCU deref helper to fix the suspicious rcu usage warning. Fixes: 3a7c1661ae13 ("net: bridge: mst: fix vlan use-after-free") Reported-by: syzbot+9bbe2de1bc9d470eb5fe@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=9bbe2de1bc9d470eb5fe Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://lore.kernel.org/r/20240609103654.914987-3-razor@blackwall.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 546ceb1dfdac866648ec959cbc71d9525bd73462 ]

I converted br_mst_set_state to RCU to avoid a vlan use-after-free
but forgot to change the vlan group dereference helper. Switch to vlan
group RCU deref helper to fix the suspicious rcu usage warning.

Fixes: 3a7c1661ae13 ("net: bridge: mst: fix vlan use-after-free")
Reported-by: syzbot+9bbe2de1bc9d470eb5fe@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=9bbe2de1bc9d470eb5fe
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20240609103654.914987-3-razor@blackwall.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: bridge: mst: pass vlan group directly to br_mst_vlan_set_state 2024-06-21T12:35:52+00:00 Nikolay Aleksandrov razor@blackwall.org 2024-06-09T10:36:53+00:00 09f4337c27f5bdeb8646a6db91488cc2f7d537ff [ Upstream commit 36c92936e868601fa1f43da6758cf55805043509 ] Pass the already obtained vlan group pointer to br_mst_vlan_set_state() instead of dereferencing it again. Each caller has already correctly dereferenced it for their context. This change is required for the following suspicious RCU dereference fix. No functional changes intended. Fixes: 3a7c1661ae13 ("net: bridge: mst: fix vlan use-after-free") Reported-by: syzbot+9bbe2de1bc9d470eb5fe@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=9bbe2de1bc9d470eb5fe Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://lore.kernel.org/r/20240609103654.914987-2-razor@blackwall.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 36c92936e868601fa1f43da6758cf55805043509 ]

Pass the already obtained vlan group pointer to br_mst_vlan_set_state()
instead of dereferencing it again. Each caller has already correctly
dereferenced it for their context. This change is required for the
following suspicious RCU dereference fix. No functional changes
intended.

Fixes: 3a7c1661ae13 ("net: bridge: mst: fix vlan use-after-free")
Reported-by: syzbot+9bbe2de1bc9d470eb5fe@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=9bbe2de1bc9d470eb5fe
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20240609103654.914987-2-razor@blackwall.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: bridge: mst: fix vlan use-after-free 2024-06-12T09:03:32+00:00 Nikolay Aleksandrov razor@blackwall.org 2024-05-13T11:06:27+00:00 8ca9a750fc711911ef616ceb627d07357b04545e [ Upstream commit 3a7c1661ae1383364cd6092d851f5e5da64d476b ] syzbot reported a suspicious rcu usage[1] in bridge's mst code. While fixing it I noticed that nothing prevents a vlan to be freed while walking the list from the same path (br forward delay timer). Fix the rcu usage and also make sure we are not accessing freed memory by making br_mst_vlan_set_state use rcu read lock. [1] WARNING: suspicious RCU usage 6.9.0-rc6-syzkaller #0 Not tainted ----------------------------- net/bridge/br_private.h:1599 suspicious rcu_dereference_protected() usage! ... stack backtrace: CPU: 1 PID: 8017 Comm: syz-executor.1 Not tainted 6.9.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712 nbp_vlan_group net/bridge/br_private.h:1599 [inline] br_mst_set_state+0x1ea/0x650 net/bridge/br_mst.c:105 br_set_state+0x28a/0x7b0 net/bridge/br_stp.c:47 br_forward_delay_timer_expired+0x176/0x440 net/bridge/br_stp_timer.c:88 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1793 expire_timers kernel/time/timer.c:1844 [inline] __run_timers kernel/time/timer.c:2418 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2429 run_timer_base kernel/time/timer.c:2438 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2448 __do_softirq+0x2c6/0x980 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758 Code: 2b 00 74 08 4c 89 f7 e8 ba d1 84 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90013657100 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920026cae2c RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8bcaca00 RDI: ffffffff8c1eaa60 RBP: ffffc90013657260 R08: ffffffff92efe507 R09: 1ffffffff25dfca0 R10: dffffc0000000000 R11: fffffbfff25dfca1 R12: 1ffff920026cae28 R13: dffffc0000000000 R14: ffffc90013657160 R15: 0000000000000246 Fixes: ec7328b59176 ("net: bridge: mst: Multiple Spanning Tree (MST) mode") Reported-by: syzbot+fa04eb8a56fd923fc5d8@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=fa04eb8a56fd923fc5d8 Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 3a7c1661ae1383364cd6092d851f5e5da64d476b ]

syzbot reported a suspicious rcu usage[1] in bridge's mst code. While
fixing it I noticed that nothing prevents a vlan to be freed while
walking the list from the same path (br forward delay timer). Fix the rcu
usage and also make sure we are not accessing freed memory by making
br_mst_vlan_set_state use rcu read lock.

[1]
 WARNING: suspicious RCU usage
 6.9.0-rc6-syzkaller #0 Not tainted
 -----------------------------
 net/bridge/br_private.h:1599 suspicious rcu_dereference_protected() usage!
 ...
 stack backtrace:
 CPU: 1 PID: 8017 Comm: syz-executor.1 Not tainted 6.9.0-rc6-syzkaller #0
 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
 Call Trace:
  <IRQ>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
  lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712
  nbp_vlan_group net/bridge/br_private.h:1599 [inline]
  br_mst_set_state+0x1ea/0x650 net/bridge/br_mst.c:105
  br_set_state+0x28a/0x7b0 net/bridge/br_stp.c:47
  br_forward_delay_timer_expired+0x176/0x440 net/bridge/br_stp_timer.c:88
  call_timer_fn+0x18e/0x650 kernel/time/timer.c:1793
  expire_timers kernel/time/timer.c:1844 [inline]
  __run_timers kernel/time/timer.c:2418 [inline]
  __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2429
  run_timer_base kernel/time/timer.c:2438 [inline]
  run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2448
  __do_softirq+0x2c6/0x980 kernel/softirq.c:554
  invoke_softirq kernel/softirq.c:428 [inline]
  __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
  sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
  </IRQ>
  <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758
 Code: 2b 00 74 08 4c 89 f7 e8 ba d1 84 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
 RSP: 0018:ffffc90013657100 EFLAGS: 00000206
 RAX: 0000000000000001 RBX: 1ffff920026cae2c RCX: 0000000000000001
 RDX: dffffc0000000000 RSI: ffffffff8bcaca00 RDI: ffffffff8c1eaa60
 RBP: ffffc90013657260 R08: ffffffff92efe507 R09: 1ffffffff25dfca0
 R10: dffffc0000000000 R11: fffffbfff25dfca1 R12: 1ffff920026cae28
 R13: dffffc0000000000 R14: ffffc90013657160 R15: 0000000000000246

Fixes: ec7328b59176 ("net: bridge: mst: Multiple Spanning Tree (MST) mode")
Reported-by: syzbot+fa04eb8a56fd923fc5d8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=fa04eb8a56fd923fc5d8
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>