syzbot

==================================================================
BUG: KCSAN: data-race in can_rcv_filter / can_rx_register

read-write to 0xffff88810507e020 of 4 bytes by task 8625 on cpu 1:
 can_rx_register+0x46c/0x4d0 net/can/af_can.c:479
 bcm_rx_setup+0xb0d/0xe10 net/can/bcm.c:1300
 bcm_sendmsg+0x1b2/0x480 net/can/bcm.c:1427
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x145/0x180 net/socket.c:742
 ____sys_sendmsg+0x31e/0x4a0 net/socket.c:2592
 ___sys_sendmsg+0x17b/0x1d0 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+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810507e020 of 4 bytes by interrupt on cpu 0:
 can_rcv_filter+0x40/0x4f0 net/can/af_can.c:586
 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:6139 [inline]
 __netif_receive_skb+0x120/0x270 net/core/dev.c:6252
 process_backlog+0x228/0x420 net/core/dev.c:6604
 __napi_poll+0x5f/0x300 net/core/dev.c:7668
 napi_poll net/core/dev.c:7731 [inline]
 net_rx_action+0x425/0x8c0 net/core/dev.c:7883
 handle_softirqs+0xba/0x290 kernel/softirq.c:622
 run_ksoftirqd+0x1c/0x30 kernel/softirq.c:1063
 smpboot_thread_fn+0x32b/0x530 kernel/smpboot.c:160
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 14 Comm: ksoftirqd/0 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
==================================================================