bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:cf:08:c3:be:1e, vlan:0) ================================================================== BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick read-write to 0xffff8881000c5ed8 of 8 bytes by interrupt on cpu 1: wq_worker_tick+0x64/0x240 kernel/workqueue.c:1508 sched_tick+0xbc/0x1f0 kernel/sched/core.c:5678 update_process_times+0x15e/0x190 kernel/time/timer.c:2480 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:1930 [inline] __hrtimer_run_queues+0x276/0x4f0 kernel/time/hrtimer.c:1994 hrtimer_interrupt+0x261/0x850 kernel/time/hrtimer.c:2113 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] __sysvec_apic_timer_interrupt+0x5f/0x1c0 arch/x86/kernel/apic/apic.c:1067 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x32/0x80 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705 nf_hook_state_init include/linux/netfilter.h:170 [inline] ebt_broute+0xb2/0x340 net/bridge/netfilter/ebtable_broute.c:57 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:6089 __netif_receive_skb_one_core net/core/dev.c:6200 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] process_backlog+0x25b/0x670 net/core/dev.c:6666 __napi_poll+0x61/0x300 net/core/dev.c:7730 napi_poll net/core/dev.c:7793 [inline] net_rx_action+0x452/0x930 net/core/dev.c:7950 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+0x658/0x690 net/core/skbuff.c:697 alloc_skb include/linux/skbuff.h:1383 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline] nsim_dev_trap_report_work+0x18a/0x640 drivers/net/netdevsim/dev.c:922 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0x4f0/0x9c0 kernel/workqueue.c:3385 worker_thread+0x58a/0x780 kernel/workqueue.c:3466 kthread+0x22a/0x280 kernel/kthread.c:436 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 read-write to 0xffff8881000c5ed8 of 8 bytes by interrupt on cpu 0: wq_worker_tick+0x64/0x240 kernel/workqueue.c:1508 sched_tick+0xbc/0x1f0 kernel/sched/core.c:5678 update_process_times+0x15e/0x190 kernel/time/timer.c:2480 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:1930 [inline] __hrtimer_run_queues+0x276/0x4f0 kernel/time/hrtimer.c:1994 hrtimer_interrupt+0x261/0x850 kernel/time/hrtimer.c:2113 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] __sysvec_apic_timer_interrupt+0x5f/0x1c0 arch/x86/kernel/apic/apic.c:1067 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x32/0x80 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705 rt6_score_route+0x32/0x380 net/ipv6/route.c:753 find_match+0x109/0x780 net/ipv6/route.c:785 __find_rr_leaf+0x160/0x500 net/ipv6/route.c:868 find_rr_leaf net/ipv6/route.c:889 [inline] rt6_select net/ipv6/route.c:933 [inline] fib6_table_lookup+0x1db/0x610 net/ipv6/route.c:2251 ip6_pol_route+0xbf/0xeb0 net/ipv6/route.c:2287 ip6_pol_route_input+0x42/0x60 net/ipv6/route.c:2344 pol_lookup_func include/net/ip6_fib.h:667 [inline] fib6_rule_lookup+0x366/0x4c0 net/ipv6/fib6_rules.c:123 ip6_route_input_lookup net/ipv6/route.c:2356 [inline] ip6_route_input+0x512/0x620 net/ipv6/route.c:2659 ip6_rcv_finish_core net/ipv6/ip6_input.c:106 [inline] ip6_rcv_finish+0x1be/0x330 net/ipv6/ip6_input.c:117 ip_sabotage_in+0x13f/0x160 net/bridge/br_netfilter_hooks.c:984 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0x78/0x180 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK include/linux/netfilter.h:316 [inline] ipv6_rcv+0x12f/0x170 net/ipv6/ip6_input.c:351 __netif_receive_skb_one_core net/core/dev.c:6202 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] netif_receive_skb_internal net/core/dev.c:6401 [inline] netif_receive_skb+0xc5/0x4c0 net/core/dev.c:6460 br_netif_receive_skb net/bridge/br_input.c:30 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] br_pass_frame_up+0x23b/0x330 net/bridge/br_input.c:70 br_handle_frame_finish+0xe23/0x1080 net/bridge/br_input.c:-1 br_nf_hook_thresh+0x233/0x270 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x51d/0x540 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x1fa/0x2e0 net/bridge/br_netfilter_ipv6.c:183 br_nf_pre_routing+0x56a/0xbe0 net/bridge/br_netfilter_hooks.c:509 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:6089 __netif_receive_skb_one_core net/core/dev.c:6200 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] process_backlog+0x25b/0x670 net/core/dev.c:6666 __napi_poll+0x61/0x300 net/core/dev.c:7730 napi_poll net/core/dev.c:7793 [inline] net_rx_action+0x452/0x930 net/core/dev.c:7950 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+0x658/0x690 net/core/skbuff.c:697 alloc_skb include/linux/skbuff.h:1383 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline] nsim_dev_trap_report_work+0x18a/0x640 drivers/net/netdevsim/dev.c:922 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0x4f0/0x9c0 kernel/workqueue.c:3385 worker_thread+0x58a/0x780 kernel/workqueue.c:3466 kthread+0x22a/0x280 kernel/kthread.c:436 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 value changed: 0x0000000001d29d20 -> 0x0000000001d2c430 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 24175 Comm: kworker/u8:20 Tainted: G W syzkaller #0 PREEMPT(full) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events_unbound nsim_dev_trap_report_work ================================================================== net_ratelimit: 55344 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:cf:08:c3:be:1e, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:cf:08:c3:be:1e, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:cf:08:c3:be:1e, vlan:0) net_ratelimit: 63365 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:cf:08:c3:be:1e, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:cf:08:c3:be:1e, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:cf:08:c3:be:1e, vlan:0)