=====================================================
BUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _inline_copy_to_user include/linux/uaccess.h:196 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 _inline_copy_to_user include/linux/uaccess.h:196 [inline]
 _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:225 [inline]
 do_insn_ioctl+0x59c/0x6d0 drivers/comedi/comedi_fops.c:1678
 comedi_unlocked_ioctl+0xa5e/0x1f60 drivers/comedi/comedi_fops.c:2303
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0x23c/0x400 fs/ioctl.c:584
 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:584
 x64_sys_call+0x1cbc/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_free_hook mm/slub.c:2343 [inline]
 slab_free mm/slub.c:4680 [inline]
 kfree+0x252/0xec0 mm/slub.c:4879
 finish_writeback_work fs/fs-writeback.c:174 [inline]
 wb_do_writeback fs/fs-writeback.c:2304 [inline]
 wb_workfn+0x5b3/0x1910 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3319
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3400
 kthread+0xd59/0xf00 kernel/kthread.c:463
 ret_from_fork+0x1e3/0x310 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Bytes 4-59 of 60 are uninitialized
Memory access of size 60 starts at ffff8880561fc140
Data copied to user address 0000200000000080

CPU: 0 UID: 0 PID: 13411 Comm: syz.4.2136 Not tainted 6.17.0-rc1-syzkaller-00116-gd7ee5bdce789 #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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