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BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: use-after-free in atomic64_read include/asm-generic/atomic-instrumented.h:837 [inline]
BUG: KASAN: use-after-free in atomic_long_read include/asm-generic/atomic-long.h:29 [inline]
BUG: KASAN: use-after-free in __mutex_unlock_slowpath+0x8e/0x610 kernel/locking/mutex.c:1227
Read of size 8 at addr ffff8880512e4008 by task iou-sqp-25887/25894

CPU: 1 PID: 25894 Comm: iou-sqp-25887 Not tainted 5.12.0-rc1-next-20210304-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0xfa/0x151 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232
 __kasan_report mm/kasan/report.c:399 [inline]
 kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
 check_region_inline mm/kasan/generic.c:180 [inline]
 kasan_check_range+0x13d/0x180 mm/kasan/generic.c:186
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic64_read include/asm-generic/atomic-instrumented.h:837 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:29 [inline]
 __mutex_unlock_slowpath+0x8e/0x610 kernel/locking/mutex.c:1227
 io_sq_thread+0x1292/0x1a50 fs/io_uring.c:6766
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Allocated by task 25887:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:427 [inline]
 ____kasan_kmalloc mm/kasan/common.c:506 [inline]
 ____kasan_kmalloc mm/kasan/common.c:465 [inline]
 __kasan_kmalloc+0x99/0xc0 mm/kasan/common.c:515
 kmalloc include/linux/slab.h:556 [inline]
 kzalloc include/linux/slab.h:686 [inline]
 io_get_sq_data fs/io_uring.c:7169 [inline]
 io_sq_offload_create fs/io_uring.c:7863 [inline]
 io_uring_create fs/io_uring.c:9417 [inline]
 io_uring_setup+0x1621/0x2950 fs/io_uring.c:9500
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 25887:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357
 ____kasan_slab_free mm/kasan/common.c:360 [inline]
 ____kasan_slab_free mm/kasan/common.c:325 [inline]
 __kasan_slab_free+0xf5/0x130 mm/kasan/common.c:367
 kasan_slab_free include/linux/kasan.h:199 [inline]
 slab_free_hook mm/slub.c:1562 [inline]
 slab_free_freelist_hook+0x72/0x1b0 mm/slub.c:1600
 slab_free mm/slub.c:3161 [inline]
 kfree+0xe5/0x7b0 mm/slub.c:4215
 io_put_sq_data fs/io_uring.c:7108 [inline]
 io_sq_thread_finish+0x3af/0x480 fs/io_uring.c:7131
 io_sq_offload_create fs/io_uring.c:7917 [inline]
 io_uring_create fs/io_uring.c:9417 [inline]
 io_uring_setup+0x228f/0x2950 fs/io_uring.c:9500
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Last potentially related work creation:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:345
 kvfree_call_rcu+0x74/0x8c0 kernel/rcu/tree.c:3597
 neigh_destroy+0x3ff/0x5f0 net/core/neighbour.c:858
 neigh_release include/net/neighbour.h:425 [inline]
 neigh_cleanup_and_release+0x1fd/0x340 net/core/neighbour.c:103
 neigh_periodic_work+0x63c/0x9e0 net/core/neighbour.c:940
 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

The buggy address belongs to the object at ffff8880512e4000
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 8 bytes inside of
 1024-byte region [ffff8880512e4000, ffff8880512e4400)
The buggy address belongs to the page:
page:0000000043e68d55 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x512e0
head:0000000043e68d55 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010841dc0
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880512e3f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880512e3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880512e4000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff8880512e4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880512e4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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