==================================================================
BUG: KCSAN: data-race in alloc_pid / copy_process

read-write to 0xffffffff8665d858 of 4 bytes by task 9562 on cpu 1:
 alloc_pid+0x542/0x6f0 kernel/pid.c:284
 copy_process+0xe72/0x1f90 kernel/fork.c:2388
 kernel_clone+0x167/0x5e0 kernel/fork.c:2784
 user_mode_thread+0x7d/0xb0 kernel/fork.c:2862
 call_usermodehelper_exec_work+0x41/0x150 kernel/umh.c:172
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310
 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffffffff8665d858 of 4 bytes by task 50 on cpu 0:
 copy_process+0x1799/0x1f90 kernel/fork.c:2527
 kernel_clone+0x167/0x5e0 kernel/fork.c:2784
 user_mode_thread+0x7d/0xb0 kernel/fork.c:2862
 call_usermodehelper_exec_work+0x41/0x150 kernel/umh.c:172
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310
 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x800000c3 -> 0x800000c4

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 50 Comm: kworker/u8:3 Tainted: G        W          6.12.0-rc5-syzkaller-00005-ge42b1a9a2557 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_unbound call_usermodehelper_exec_work
==================================================================
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered forwarding state