syzbot

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BUG: KCSAN: data-race in qrtr_endpoint_unregister / qrtr_node_enqueue

write to 0xffff88811a5c3c20 of 8 bytes by task 3617 on cpu 1:
 qrtr_endpoint_unregister+0x96/0x390 net/qrtr/af_qrtr.c:633
 qrtr_tun_release+0x22/0x50 net/qrtr/tun.c:131
 __fput+0x298/0x650 fs/file_table.c:468
 ____fput+0x1c/0x30 fs/file_table.c:496
 task_work_run+0x12e/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811a5c3c20 of 8 bytes by task 3610 on cpu 0:
 qrtr_tx_wait net/qrtr/af_qrtr.c:290 [inline]
 qrtr_node_enqueue+0x504/0x710 net/qrtr/af_qrtr.c:348
 qrtr_bcast_enqueue+0xd5/0x140 net/qrtr/af_qrtr.c:891
 qrtr_sendmsg+0x4de/0x590 net/qrtr/af_qrtr.c:992
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x145/0x180 net/socket.c:729
 sock_write_iter+0x165/0x1b0 net/socket.c:1179
 io_write+0x60f/0xd40 io_uring/rw.c:1163
 __io_issue_sqe+0xfe/0x2e0 io_uring/io_uring.c:1773
 io_issue_sqe+0x53/0x970 io_uring/io_uring.c:1796
 io_queue_sqe io_uring/io_uring.c:2025 [inline]
 io_submit_sqe io_uring/io_uring.c:2285 [inline]
 io_submit_sqes+0x675/0x1060 io_uring/io_uring.c:2398
 __do_sys_io_uring_enter io_uring/io_uring.c:3465 [inline]
 __se_sys_io_uring_enter+0x1c1/0x1b70 io_uring/io_uring.c:3399
 __x64_sys_io_uring_enter+0x78/0x90 io_uring/io_uring.c:3399
 x64_sys_call+0x2de1/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:427
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff88811b21d040 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3610 Comm: syz.3.42 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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