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BUG: KCSAN: data-race in can_can_gw_rcv / can_can_gw_rcv

read-write to 0xffff888100173800 of 4 bytes by interrupt on cpu 1:
 can_can_gw_rcv+0x863/0x870 net/can/gw.c:572
 deliver net/can/af_can.c:575 [inline]
 can_rcv_filter+0xc3/0x480 net/can/af_can.c:602
 can_receive+0x13e/0x190 net/can/af_can.c:674
 can_rcv+0x17d/0x1f0 net/can/af_can.c:699
 __netif_receive_skb_one_core net/core/dev.c:6202 [inline]
 __netif_receive_skb net/core/dev.c:6315 [inline]
 process_backlog+0x363/0x670 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
 run_ksoftirqd+0x1c/0x30 kernel/softirq.c:1076
 smpboot_thread_fn+0x32a/0x510 kernel/smpboot.c:160
 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 0xffff888100173800 of 4 bytes by interrupt on cpu 0:
 can_can_gw_rcv+0x863/0x870 net/can/gw.c:572
 deliver net/can/af_can.c:575 [inline]
 can_rcv_filter+0xc3/0x480 net/can/af_can.c:602
 can_receive+0x13e/0x190 net/can/af_can.c:674
 can_rcv+0x17d/0x1f0 net/can/af_can.c:699
 __netif_receive_skb_one_core net/core/dev.c:6202 [inline]
 __netif_receive_skb net/core/dev.c:6315 [inline]
 process_backlog+0x363/0x670 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]
 alloc_uevent_skb+0x5c/0x120 lib/kobject_uevent.c:289
 uevent_net_broadcast_tagged lib/kobject_uevent.c:352 [inline]
 kobject_uevent_net_broadcast+0xfb/0x410 lib/kobject_uevent.c:415
 kobject_uevent_env+0x43d/0x570 lib/kobject_uevent.c:611
 kobject_uevent+0x1d/0x30 lib/kobject_uevent.c:659
 device_add+0x41f/0x790 drivers/base/core.c:3672
 netdev_register_kobject+0x109/0x230 net/core/net-sysfs.c:2343
 register_netdevice+0xaaf/0x1160 net/core/dev.c:11420
 __ip_tunnel_create+0x31d/0x430 net/ipv4/ip_tunnel.c:268
 ip_tunnel_init_net+0x210/0x490 net/ipv4/ip_tunnel.c:1147
 erspan_init_net+0x35/0x40 net/ipv4/ip_gre.c:1780
 ops_init+0x22a/0x2e0 net/core/net_namespace.c:137
 setup_net+0x9f/0x230 net/core/net_namespace.c:446
 copy_net_ns+0x310/0x450 net/core/net_namespace.c:579
 create_new_namespaces+0x20e/0x440 kernel/nsproxy.c:132
 copy_namespaces+0x1ad/0x210 kernel/nsproxy.c:195
 copy_process+0x10ae/0x23a0 kernel/fork.c:2265
 kernel_clone+0x1a5/0x5e0 kernel/fork.c:2723
 __do_sys_clone kernel/fork.c:2864 [inline]
 __se_sys_clone kernel/fork.c:2848 [inline]
 __x64_sys_clone+0x143/0x180 kernel/fork.c:2848
 x64_sys_call+0x1222/0x3020 arch/x86/include/generated/asm/syscalls_64.h:57
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00002ddd -> 0x00002dde

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 8815 Comm: syz.3.1876 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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