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BUG: KCSAN: data-race in bcm_rx_setup / bcm_rx_update_and_send

write to 0xffff88811ab24050 of 16 bytes by task 5054 on cpu 1:
 bcm_rx_setup+0x7dd/0xe00 net/can/bcm.c:1260
 bcm_sendmsg+0x1bb/0x4a0 net/can/bcm.c:1427
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x145/0x170 net/socket.c:742
 ____sys_sendmsg+0x31e/0x4a0 net/socket.c:2592
 ___sys_sendmsg+0x195/0x1e0 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+0xd4/0x160 net/socket.c:2681
 x64_sys_call+0x17ba/0x3000 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811ab24050 of 16 bytes by interrupt on cpu 0:
 bcm_rx_changed net/can/bcm.c:501 [inline]
 bcm_rx_update_and_send+0x392/0x420 net/can/bcm.c:553
 bcm_rx_handler+0x2b0/0x580 net/can/bcm.c:739
 deliver net/can/af_can.c:575 [inline]
 can_rcv_filter+0x3c6/0x4f0 net/can/af_can.c:636
 can_receive+0xfb/0x1c0 net/can/af_can.c:662
 canfd_rcv+0xed/0x190 net/can/af_can.c:705
 __netif_receive_skb_one_core net/core/dev.c:6152 [inline]
 __netif_receive_skb+0x120/0x270 net/core/dev.c:6265
 process_backlog+0x228/0x420 net/core/dev.c:6617
 __napi_poll+0x5f/0x300 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 kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x39/0xc0 kernel/softirq.c:723
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 finish_task_switch+0x82/0x280 kernel/sched/core.c:5114
 context_switch kernel/sched/core.c:5259 [inline]
 __schedule+0x82d/0xc90 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x5e/0xd0 kernel/sched/core.c:6960
 futex_do_wait kernel/futex/waitwake.c:358 [inline]
 __futex_wait+0x121/0x260 kernel/futex/waitwake.c:687
 futex_wait+0x9c/0x1d0 kernel/futex/waitwake.c:715
 do_futex+0x2bf/0x380 kernel/futex/syscalls.c:130
 __do_sys_futex kernel/futex/syscalls.c:207 [inline]
 __se_sys_futex+0x2f6/0x370 kernel/futex/syscalls.c:188
 __x64_sys_futex+0x78/0x90 kernel/futex/syscalls.c:188
 x64_sys_call+0x2bc2/0x3000 arch/x86/include/generated/asm/syscalls_64.h:203
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5056 Comm: syz.4.451 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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