syzbot

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BUG: KCSAN: data-race in kick_pool / wq_worker_running

read-write to 0xffff888237d2a8e4 of 4 bytes by task 3411 on cpu 1:
 wq_worker_running+0x9b/0x120 kernel/workqueue.c:1434
 synchronize_rcu_expedited+0x5f8/0x770 kernel/rcu/tree_exp.h:976
 synchronize_rcu+0x35/0x2e0 kernel/rcu/tree.c:3389
 xfrm_state_gc_task+0x98/0x590 net/xfrm/xfrm_state.c:633
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405
 worker_thread+0x569/0x750 kernel/workqueue.c:3486
 kthread+0x221/0x270 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 to 0xffff888237d2a8e4 of 4 bytes by task 15118 on cpu 0:
 need_more_worker kernel/workqueue.c:952 [inline]
 kick_pool+0x49/0x2d0 kernel/workqueue.c:1274
 __queue_work+0x8e9/0xb90 kernel/workqueue.c:2402
 queue_work_on+0xa9/0x140 kernel/workqueue.c:2452
 queue_work include/linux/workqueue.h:699 [inline]
 schedule_work include/linux/workqueue.h:760 [inline]
 __xfrm_state_destroy net/xfrm/xfrm_state.c:807 [inline]
 xfrm_state_put include/net/xfrm.h:940 [inline]
 xfrm_state_find+0x1dc6/0x33a0 net/xfrm/xfrm_state.c:1639
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2516 [inline]
 xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:2567 [inline]
 xfrm_resolve_and_create_bundle+0x574/0x1f10 net/xfrm/xfrm_policy.c:2865
 xfrm_lookup_with_ifid+0x448/0x1570 net/xfrm/xfrm_policy.c:3199
 xfrm_lookup net/xfrm/xfrm_policy.c:3330 [inline]
 xfrm_lookup_route+0x3a/0x110 net/xfrm/xfrm_policy.c:3341
 ip6_dst_lookup_flow+0xc4/0xf0 net/ipv6/ip6_output.c:1297
 rawv6_sendmsg+0xbd3/0x1150 net/ipv6/raw.c:895
 inet_sendmsg+0xc5/0xd0 net/ipv4/af_inet.c:865
 sock_sendmsg_nosec net/socket.c:776 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x4e8/0x580 net/socket.c:2684
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2738
 __sys_sendmmsg+0x185/0x320 net/socket.c:2827
 __do_sys_sendmmsg net/socket.c:2854 [inline]
 __se_sys_sendmmsg net/socket.c:2851 [inline]
 __x64_sys_sendmmsg+0x57/0x70 net/socket.c:2851
 x64_sys_call+0x27aa/0x3020 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 15118 Comm: syz.8.11744 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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