================================================================== BUG: KCSAN: data-race in copy_process / free_pid read-write to 0xffffffff8685fc48 of 4 bytes by task 407 on cpu 0: free_pid+0x77/0x180 kernel/pid.c:126 free_pids+0x7a/0xb0 kernel/pid.c:159 release_task+0x9a9/0xb60 kernel/exit.c:296 wait_task_zombie kernel/exit.c:1264 [inline] wait_consider_task+0x114a/0x1660 kernel/exit.c:1491 do_wait_pid kernel/exit.c:1630 [inline] __do_wait+0x34a/0x510 kernel/exit.c:1665 do_wait+0xb7/0x260 kernel/exit.c:1706 kernel_wait+0x51/0xc0 kernel/exit.c:1882 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0x9c/0x160 kernel/umh.c:163 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3319 worker_thread+0x582/0x770 kernel/workqueue.c:3400 kthread+0x489/0x510 kernel/kthread.c:463 ret_from_fork+0x11f/0x1b0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 read to 0xffffffff8685fc48 of 4 bytes by task 382 on cpu 1: copy_process+0x14a6/0x2000 kernel/fork.c:2348 kernel_clone+0x16c/0x5c0 kernel/fork.c:2605 user_mode_thread+0x7d/0xb0 kernel/fork.c:2683 call_usermodehelper_exec_sync kernel/umh.c:132 [inline] call_usermodehelper_exec_work+0x7a/0x160 kernel/umh.c:163 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3319 worker_thread+0x582/0x770 kernel/workqueue.c:3400 kthread+0x489/0x510 kernel/kthread.c:463 ret_from_fork+0x11f/0x1b0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 value changed: 0x80000092 -> 0x80000091 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 382 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: events_unbound call_usermodehelper_exec_work ================================================================== netdevsim netdevsim4 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim1 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim1 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim1 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim1 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim2 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim2 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim2 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim2 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0