================================================================== BUG: KASAN: use-after-free in debugfs_remove+0x10d/0x130 fs/debugfs/inode.c:687 Read of size 8 at addr ffff888065738220 by task kworker/1:3/30759 CPU: 1 PID: 30759 Comm: kworker/1:3 Not tainted 4.19.60 #34 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 29401: 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 kobject: 'queues' (000000006eeafead): kobject_uevent_env: filter function caused the event to drop! do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9: 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 kobject: 'loop0' (00000000f3af8bed): kobject_add_internal: parent: 'block', set: 'devices' __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 kobject: 'rx-0' (000000000432c063): kobject_add_internal: parent: 'queues', set: 'queues' The buggy address belongs to the object at ffff8880657381e0 which belongs to the cache dentry(49:syz1) of size 288 The buggy address is located 64 bytes inside of 288-byte region [ffff8880657381e0, ffff888065738300) The buggy address belongs to the page: page:ffffea000195ce00 count:1 mapcount:0 mapping:ffff88806a2e9b00 index:0xffff888065738760 flags: 0x1fffc0000000100(slab) raw: 01fffc0000000100 ffffea0001728e48 ffffea000161b8c8 ffff88806a2e9b00 kobject: 'rx-0' (000000000432c063): kobject_uevent_env raw: ffff888065738760 ffff888065738080 000000010000000a ffff8880a54f2a00 page dumped because: kasan: bad access detected page->mem_cgroup:ffff8880a54f2a00 Memory state around the buggy address: ffff888065738100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888065738180: 00 00 00 00 fc fc fc fc fc fc fc fc fb fb fb fb >ffff888065738200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888065738280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888065738300: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ================================================================== kobject: 'rx-0' (000000000432c063): fill_kobj_path: path = '/devices/virtual/net/nr0/queues/rx-0'