================================================================== BUG: KASAN: use-after-free in debugfs_remove+0x4f/0xf0 fs/debugfs/inode.c:705 Read of size 8 at addr ffff8880466241e0 by task kworker/1:3/9657 CPU: 1 PID: 9657 Comm: kworker/1:3 Not tainted 5.3.0-rc3+ #68 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+0x1d8/0x2f8 lib/dump_stack.c:113 print_address_description+0x75/0x5b0 mm/kasan/report.c:351 __kasan_report+0x14b/0x1c0 mm/kasan/report.c:482 kasan_report+0x26/0x50 mm/kasan/common.c:612 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 debugfs_remove+0x4f/0xf0 fs/debugfs/inode.c:705 blk_trace_free kernel/trace/blktrace.c:312 [inline] blk_trace_cleanup kernel/trace/blktrace.c:339 [inline] __blk_trace_remove+0xa5/0x180 kernel/trace/blktrace.c:352 blk_trace_shutdown+0x20b/0x260 kernel/trace/blktrace.c:747 __blk_release_queue+0x1bd/0x250 block/blk-sysfs.c:902 process_one_work+0x7ef/0x10e0 kernel/workqueue.c:2269 worker_thread+0xc01/0x1630 kernel/workqueue.c:2415 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 17156: save_stack mm/kasan/common.c:69 [inline] set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:487 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:495 slab_post_alloc_hook mm/slab.h:520 [inline] slab_alloc mm/slab.c:3319 [inline] kmem_cache_alloc+0x1f5/0x2e0 mm/slab.c:3483 __d_alloc+0x2d/0x6e0 fs/dcache.c:1688 d_alloc fs/dcache.c:1767 [inline] d_alloc_parallel+0x7f/0x1430 fs/dcache.c:2519 __lookup_slow+0xa7/0x380 fs/namei.c:1652 lookup_one_len+0x123/0x220 fs/namei.c:2541 start_creating+0xd3/0x270 fs/debugfs/inode.c:312 __debugfs_create_file+0x75/0x450 fs/debugfs/inode.c:357 debugfs_create_file+0x4a/0x60 fs/debugfs/inode.c:413 do_blk_trace_setup+0x439/0xaa0 kernel/trace/blktrace.c:524 __blk_trace_setup kernel/trace/blktrace.c:571 [inline] blk_trace_ioctl+0x24c/0x7d0 kernel/trace/blktrace.c:710 blkdev_ioctl+0x1363/0x2990 block/ioctl.c:592 block_ioctl+0xbd/0x100 fs/block_dev.c:1994 do_vfs_ioctl+0x744/0x1730 fs/ioctl.c:46 ksys_ioctl fs/ioctl.c:713 [inline] __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0xe3/0x120 fs/ioctl.c:718 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9: save_stack mm/kasan/common.c:69 [inline] set_track mm/kasan/common.c:77 [inline] __kasan_slab_free+0x12a/0x1e0 mm/kasan/common.c:449 kasan_slab_free+0xe/0x10 mm/kasan/common.c:457 __cache_free mm/slab.c:3425 [inline] kmem_cache_free+0x81/0xf0 mm/slab.c:3693 __d_free+0x20/0x30 fs/dcache.c:271 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2114 [inline] rcu_core+0x892/0xf10 kernel/rcu/tree.c:2314 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2323 __do_softirq+0x333/0x7c4 arch/x86/include/asm/paravirt.h:778 The buggy address belongs to the object at ffff8880466241a0 which belongs to the cache dentry(49:syz2) of size 288 The buggy address is located 64 bytes inside of 288-byte region [ffff8880466241a0, ffff8880466242c0) The buggy address belongs to the page: page:ffffea0001198900 refcount:1 mapcount:0 mapping:ffff88809032ac40 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00011f83c8 ffffea00011f8108 ffff88809032ac40 raw: 0000000000000000 ffff888046624040 000000010000000b 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888046624080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888046624100: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc >ffff888046624180: fc fc fc fc fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888046624200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888046624280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================