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BUG: KASAN: use-after-free in __list_del_entry_valid+0x98/0x100 lib/list_debug.c:54
Read of size 8 at addr ffff8881c9bd0400 by task kworker/u4:14/3416

CPU: 0 PID: 3416 Comm: kworker/u4:14 Not tainted 5.4.68-syzkaller-00474-g2a7d52383a14 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: io_ring-wq io_sq_wq_submit_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b0/0x21e lib/dump_stack.c:118
 print_address_description+0x96/0x5d0 mm/kasan/report.c:374
 __kasan_report+0x14b/0x1c0 mm/kasan/report.c:506
 kasan_report+0x27/0x50 mm/kasan/common.c:634
 __list_del_entry_valid+0x98/0x100 lib/list_debug.c:54
 __list_del_entry include/linux/list.h:131 [inline]
 list_del_init include/linux/list.h:190 [inline]
 io_sq_wq_submit_work+0x7d5/0x1480 fs/io_uring.c:2272
 process_one_work+0x777/0xf90 kernel/workqueue.c:2274
 worker_thread+0xa8f/0x1430 kernel/workqueue.c:2420
 kthread+0x317/0x340 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Allocated by task 18861:
 save_stack mm/kasan/common.c:69 [inline]
 set_track mm/kasan/common.c:77 [inline]
 __kasan_kmalloc+0x117/0x1b0 mm/kasan/common.c:510
 slab_post_alloc_hook mm/slab.h:584 [inline]
 kmem_cache_alloc_bulk+0x1cf/0x250 mm/slub.c:3233
 io_get_req+0x27f/0x850 fs/io_uring.c:650
 io_submit_sqe+0x83/0xe90 fs/io_uring.c:2569
 io_ring_submit fs/io_uring.c:2957 [inline]
 __do_sys_io_uring_enter fs/io_uring.c:3834 [inline]
 __se_sys_io_uring_enter+0x8ce/0x1f80 fs/io_uring.c:3795
 do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 3416:
 save_stack mm/kasan/common.c:69 [inline]
 set_track mm/kasan/common.c:77 [inline]
 kasan_set_free_info mm/kasan/common.c:332 [inline]
 __kasan_slab_free+0x168/0x220 mm/kasan/common.c:471
 slab_free_hook mm/slub.c:1443 [inline]
 slab_free_freelist_hook+0xd0/0x150 mm/slub.c:1476
 slab_free mm/slub.c:3041 [inline]
 kmem_cache_free+0xac/0x5c0 mm/slub.c:3057
 io_put_req fs/io_uring.c:762 [inline]
 io_poll_complete_work+0x725/0x930 fs/io_uring.c:1835
 process_one_work+0x777/0xf90 kernel/workqueue.c:2274
 worker_thread+0xa8f/0x1430 kernel/workqueue.c:2420
 kthread+0x317/0x340 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff8881c9bd0300
 which belongs to the cache io_kiocb of size 264
The buggy address is located 256 bytes inside of
 264-byte region [ffff8881c9bd0300, ffff8881c9bd0408)
The buggy address belongs to the page:
page:ffffea000726f400 refcount:1 mapcount:0 mapping:ffff8881dab9b400 index:0x0 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 ffffea00073bd080 0000000e0000000e ffff8881dab9b400
raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881c9bd0300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881c9bd0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881c9bd0400: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff8881c9bd0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881c9bd0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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