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BUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak-after-free in copy_to_user_iter lib/iov_iter.c:24 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_ubuf include/linux/iov_iter.h:30 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance2 include/linux/iov_iter.h:302 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance include/linux/iov_iter.h:330 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _copy_to_iter+0xef3/0x33f0 lib/iov_iter.c:185
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:30 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:302 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 _copy_to_iter+0xef3/0x33f0 lib/iov_iter.c:185
 copy_page_to_iter+0x482/0x910 lib/iov_iter.c:362
 copy_folio_to_iter include/linux/uio.h:204 [inline]
 filemap_read+0x1cda/0x2300 mm/filemap.c:2799
 blkdev_read_iter+0x89f/0xb00 block/fops.c:859
 new_sync_read fs/read_write.c:491 [inline]
 vfs_read+0x8ed/0xf90 fs/read_write.c:572
 ksys_read fs/read_write.c:715 [inline]
 __do_sys_read fs/read_write.c:724 [inline]
 __se_sys_read fs/read_write.c:722 [inline]
 __x64_sys_read+0x1fb/0x4d0 fs/read_write.c:722
 x64_sys_call+0x2f9c/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_free_hook mm/slub.c:2456 [inline]
 slab_free_freelist_hook mm/slub.c:2559 [inline]
 slab_free_bulk mm/slub.c:6651 [inline]
 kmem_cache_free_bulk+0x1b74/0x2b20 mm/slub.c:7335
 kfree_bulk include/linux/slab.h:830 [inline]
 kvfree_rcu_bulk+0x12d/0x570 mm/slab_common.c:1522
 kfree_rcu_work+0x326/0x820 mm/slab_common.c:1600
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3346
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3427
 kthread+0xd5c/0xf00 kernel/kthread.c:463
 ret_from_fork+0x1f5/0x4c0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Bytes 884-887 of 4096 are uninitialized
Memory access of size 4096 starts at ffff88805165f000
Data copied to user address 00007f02751d3000

CPU: 1 UID: 0 PID: 6033 Comm: udevd Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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