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BUG: KASAN: use-after-free in debugfs_remove+0x10d/0x130 /fs/debugfs/inode.c:687
Read of size 8 at addr ffff88808d6504e0 by task kworker/1:0/19

CPU: 1 PID: 19 Comm: kworker/1:0 Not tainted 4.19.60 #33
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events __blk_release_queue
Call Trace:
 __dump_stack /lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 /lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d /mm/kasan/report.c:256
 kasan_report_error /mm/kasan/report.c:354 [inline]
 kasan_report /mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x8c/0x2ba /mm/kasan/report.c:396
 __asan_report_load8_noabort+0x14/0x20 /mm/kasan/report.c:433
 debugfs_remove+0x10d/0x130 /fs/debugfs/inode.c:687
 blk_trace_free+0x38/0x140 /kernel/trace/blktrace.c:312
 blk_trace_cleanup /kernel/trace/blktrace.c:339 [inline]
 __blk_trace_remove+0x78/0xa0 /kernel/trace/blktrace.c:352
 blk_trace_shutdown+0x67/0x90 /kernel/trace/blktrace.c:752
 __blk_release_queue+0x225/0x4f0 /block/blk-sysfs.c:852
 process_one_work+0x989/0x1750 /kernel/workqueue.c:2153
 worker_thread+0x98/0xe40 /kernel/workqueue.c:2296
 kthread+0x354/0x420 /kernel/kthread.c:246
 ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:415

Allocated by task 10944:
 save_stack+0x45/0xd0 /mm/kasan/kasan.c:448
 set_track /mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc /mm/kasan/kasan.c:553 [inline]
 kasan_kmalloc+0xce/0xf0 /mm/kasan/kasan.c:531
 kasan_slab_alloc+0xf/0x20 /mm/kasan/kasan.c:490
 kmem_cache_alloc+0x12e/0x700 /mm/slab.c:3559
 __d_alloc+0x2e/0x9c0 /fs/dcache.c:1610
 d_alloc+0x4d/0x280 /fs/dcache.c:1694
 d_alloc_parallel+0xf4/0x1bb0 /fs/dcache.c:2441
 __lookup_slow+0x1ab/0x500 /fs/namei.c:1654
 lookup_one_len+0x16d/0x1a0 /fs/namei.c:2543
 start_creating /fs/debugfs/inode.c:313 [inline]
 start_creating+0xbf/0x1e0 /fs/debugfs/inode.c:289
 __debugfs_create_file+0x65/0x400 /fs/debugfs/inode.c:352
 debugfs_create_file+0x5a/0x70 /fs/debugfs/inode.c:404
 do_blk_trace_setup+0x376/0xb90 /kernel/trace/blktrace.c:528
 __blk_trace_setup+0xe3/0x190 /kernel/trace/blktrace.c:577
 blk_trace_ioctl+0x170/0x300 /kernel/trace/blktrace.c:716
 blkdev_ioctl+0x126/0x1ac0 /block/ioctl.c:587
 block_ioctl+0xee/0x130 /fs/block_dev.c:1891
 vfs_ioctl /fs/ioctl.c:46 [inline]
 file_ioctl /fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xd5f/0x1380 /fs/ioctl.c:688
 ksys_ioctl+0xab/0xd0 /fs/ioctl.c:705
 __do_sys_ioctl /fs/ioctl.c:712 [inline]
 __se_sys_ioctl /fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x73/0xb0 /fs/ioctl.c:710
 do_syscall_64+0xfd/0x620 /arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 18:
 save_stack+0x45/0xd0 /mm/kasan/kasan.c:448
 set_track /mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 /mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 /mm/kasan/kasan.c:528
 __cache_free /mm/slab.c:3503 [inline]
 kmem_cache_free+0x86/0x260 /mm/slab.c:3765
 __d_free+0x20/0x30 /fs/dcache.c:257
 __rcu_reclaim /kernel/rcu/rcu.h:236 [inline]
 rcu_do_batch /kernel/rcu/tree.c:2584 [inline]
 invoke_rcu_callbacks /kernel/rcu/tree.c:2897 [inline]
 __rcu_process_callbacks /kernel/rcu/tree.c:2864 [inline]
 rcu_process_callbacks+0xba0/0x1a30 /kernel/rcu/tree.c:2881
 __do_softirq+0x25c/0x921 /kernel/softirq.c:292

The buggy address belongs to the object at ffff88808d6504a0
 which belongs to the cache dentry of size 288
The buggy address is located 64 bytes inside of
 288-byte region [ffff88808d6504a0, ffff88808d6505c0)
The buggy address belongs to the page:
page:ffffea0002359400 count:1 mapcount:0 mapping:ffff88812c297840 index:0x0
flags: 0x1fffc0000000100(slab)
raw: 01fffc0000000100 ffffea000235a048 ffffea0002359488 ffff88812c297840
raw: 0000000000000000 ffff88808d650080 000000010000000b 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808d650380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808d650400: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88808d650480: fc fc fc fc fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff88808d650500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808d650580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
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