bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) ================================================================== BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick read-write to 0xffff8881000738b8 of 8 bytes by interrupt on cpu 0: wq_worker_tick+0x60/0x230 kernel/workqueue.c:1474 sched_tick+0xd7/0x210 kernel/sched/core.c:5550 update_process_times+0x15e/0x190 kernel/time/timer.c:2479 tick_sched_handle kernel/time/tick-sched.c:298 [inline] tick_nohz_handler+0x275/0x3d0 kernel/time/tick-sched.c:319 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x20f/0x590 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x269/0x810 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x5f/0x1d0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x32/0x80 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 check_kcov_mode kernel/kcov.c:183 [inline] write_comp_data kernel/kcov.c:246 [inline] __sanitizer_cov_trace_const_cmp1+0x2e/0x90 kernel/kcov.c:300 skb_ext_exist include/linux/skbuff.h:5063 [inline] skb_ext_find include/linux/skbuff.h:5074 [inline] nf_bridge_info_get include/linux/netfilter_bridge.h:30 [inline] br_nf_pre_routing_ipv6+0xe0/0x2e0 net/bridge/br_netfilter_ipv6.c:178 br_nf_pre_routing+0x52b/0xbd0 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0x85f/0xa60 net/bridge/br_input.c:442 __netif_receive_skb_core+0x5b1/0x1950 net/core/dev.c:6039 __netif_receive_skb_one_core net/core/dev.c:6150 [inline] __netif_receive_skb net/core/dev.c:6265 [inline] process_backlog+0x25b/0x670 net/core/dev.c:6617 __napi_poll+0x5f/0x310 net/core/dev.c:7681 napi_poll net/core/dev.c:7744 [inline] net_rx_action+0x452/0x930 net/core/dev.c:7896 handle_softirqs+0xb9/0x280 kernel/softirq.c:622 do_softirq+0x45/0x60 kernel/softirq.c:523 __local_bh_enable_ip+0x70/0x80 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] __alloc_skb+0x477/0x4b0 net/core/skbuff.c:674 alloc_skb include/linux/skbuff.h:1383 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:818 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:875 [inline] nsim_dev_trap_report_work+0x18a/0x630 drivers/net/netdevsim/dev.c:921 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0x4cd/0x9d0 kernel/workqueue.c:3340 worker_thread+0x6bc/0x8b0 kernel/workqueue.c:3421 kthread+0x488/0x510 kernel/kthread.c:463 ret_from_fork+0x148/0x280 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 read-write to 0xffff8881000738b8 of 8 bytes by interrupt on cpu 1: wq_worker_tick+0x60/0x230 kernel/workqueue.c:1474 sched_tick+0xd7/0x210 kernel/sched/core.c:5550 update_process_times+0x15e/0x190 kernel/time/timer.c:2479 tick_sched_handle kernel/time/tick-sched.c:298 [inline] tick_nohz_handler+0x275/0x3d0 kernel/time/tick-sched.c:319 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x20f/0x590 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x269/0x810 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x5f/0x1d0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x32/0x80 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 __sanitizer_cov_trace_const_cmp4+0x8/0x90 kernel/kcov.c:315 ipv4_is_multicast include/linux/in.h:45 [inline] ip_route_input_slow net/ipv4/route.c:2295 [inline] ip_route_input_rcu+0x604/0x1c10 net/ipv4/route.c:2543 ip_route_input_noref+0x5f/0x90 net/ipv4/route.c:2554 arp_process+0x65f/0xf40 net/ipv4/arp.c:841 NF_HOOK+0x128/0x160 include/linux/netfilter.h:318 arp_rcv+0x218/0x2c0 net/ipv4/arp.c:996 __netif_receive_skb_one_core net/core/dev.c:6152 [inline] __netif_receive_skb net/core/dev.c:6265 [inline] process_backlog+0x363/0x670 net/core/dev.c:6617 __napi_poll+0x5f/0x310 net/core/dev.c:7681 napi_poll net/core/dev.c:7744 [inline] net_rx_action+0x452/0x930 net/core/dev.c:7896 handle_softirqs+0xb9/0x280 kernel/softirq.c:622 do_softirq+0x45/0x60 kernel/softirq.c:523 __local_bh_enable_ip+0x70/0x80 kernel/softirq.c:450 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline] _raw_spin_unlock_bh+0x18/0x20 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:890 [inline] nsim_dev_trap_report_work+0x52b/0x630 drivers/net/netdevsim/dev.c:921 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0x4cd/0x9d0 kernel/workqueue.c:3340 worker_thread+0x6bc/0x8b0 kernel/workqueue.c:3421 kthread+0x488/0x510 kernel/kthread.c:463 ret_from_fork+0x148/0x280 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 value changed: 0x00000000014af690 -> 0x00000000014b1da0 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 5093 Comm: kworker/u8:26 Tainted: G W syzkaller #0 PREEMPT(voluntary) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: events_unbound nsim_dev_trap_report_work ================================================================== net_ratelimit: 56617 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) net_ratelimit: 66401 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)