syzbot

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BUG: KMSAN: use-after-free in __fput+0x42b/0xf20 fs/file_table.c:262
CPU: 1 PID: 26 Comm: kworker/1:1 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events delayed_fput
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:201
 __fput+0x42b/0xf20 fs/file_table.c:262
 delayed_fput+0x7a/0xe0 fs/file_table.c:309
 process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
 worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
 kthread+0x551/0x590 kernel/kthread.c:293
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:143 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:126
 kmsan_slab_free+0x6e/0xb0 mm/kmsan/kmsan_hooks.c:105
 slab_free_freelist_hook mm/slub.c:1581 [inline]
 slab_free mm/slub.c:3158 [inline]
 kmem_cache_free+0x2f7/0xd50 mm/slub.c:3174
 file_free_rcu+0x15d/0x190 fs/file_table.c:50
 rcu_do_batch kernel/rcu/tree.c:2428 [inline]
 rcu_core+0xf35/0x1e90 kernel/rcu/tree.c:2656
 rcu_core_si+0xe/0x10 kernel/rcu/tree.c:2665
 __do_softirq+0x2ea/0x7f5 kernel/softirq.c:299
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