devpts: called with bogus options devpts: called with bogus options devpts: called with bogus options devpts: called with bogus options ================================================================== BUG: KASAN: use-after-free in debugfs_remove fs/debugfs/inode.c:662 [inline] BUG: KASAN: use-after-free in debugfs_remove+0xfb/0x120 fs/debugfs/inode.c:654 Read of size 8 at addr ffff8880a7773640 by task kworker/1:1/23 CPU: 1 PID: 23 Comm: kworker/1:1 Not tainted 4.14.151 #0 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:17 [inline] dump_stack+0x138/0x197 lib/dump_stack.c:53 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 debugfs_remove fs/debugfs/inode.c:662 [inline] debugfs_remove+0xfb/0x120 fs/debugfs/inode.c:654 blk_trace_free+0x38/0x140 kernel/trace/blktrace.c:324 blk_trace_cleanup kernel/trace/blktrace.c:351 [inline] blk_trace_remove+0x59/0x80 kernel/trace/blktrace.c:364 blk_trace_shutdown+0x4f/0x60 kernel/trace/blktrace.c:728 __blk_release_queue+0x22e/0x4d0 block/blk-sysfs.c:830 process_one_work+0x863/0x1600 kernel/workqueue.c:2114 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Allocated by task 6974: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc mm/kasan/kasan.c:551 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529 kobject: 'loop0' (ffff888083f6a6e0): kobject_add_internal: parent: 'block', set: 'devices' kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:489 kobject: 'loop0' (ffff888083f6a6e0): kobject_uevent_env kmem_cache_alloc+0x12e/0x780 mm/slab.c:3552 __d_alloc+0x2d/0x9f0 fs/dcache.c:1623 d_alloc+0x4d/0x270 fs/dcache.c:1710 __lookup_hash fs/namei.c:1570 [inline] __lookup_hash+0x58/0x180 fs/namei.c:1562 lookup_one_len+0x27b/0x3a0 fs/namei.c:2538 start_creating fs/debugfs/inode.c:314 [inline] start_creating+0xa6/0x1b0 fs/debugfs/inode.c:290 kobject: 'loop0' (ffff888083f6a6e0): kobject_uevent_env: uevent_suppress caused the event to drop! __debugfs_create_file+0x53/0x3d0 fs/debugfs/inode.c:353 debugfs_create_file+0x5a/0x70 fs/debugfs/inode.c:404 do_blk_trace_setup+0x32d/0xb10 kernel/trace/blktrace.c:529 blk_trace_setup+0xbd/0x140 kernel/trace/blktrace.c:579 blk_trace_ioctl+0x147/0x270 kernel/trace/blktrace.c:694 blkdev_ioctl+0x100/0x1860 block/ioctl.c:580 block_ioctl+0xde/0x120 fs/block_dev.c:1881 kobject: 'holders' (ffff888086dadc00): kobject_add_internal: parent: 'loop0', set: '' vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 kobject: 'slaves' (ffff888086dadb80): kobject_add_internal: parent: 'loop0', set: '' Freed by task 0: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 kobject: 'loop0' (ffff888083f6a6e0): kobject_uevent_env set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kmem_cache_free+0x83/0x2b0 mm/slab.c:3758 __d_free+0x20/0x30 fs/dcache.c:270 __rcu_reclaim kernel/rcu/rcu.h:195 [inline] rcu_do_batch kernel/rcu/tree.c:2699 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline] rcu_process_callbacks+0x7b8/0x12b0 kernel/rcu/tree.c:2946 kobject: 'loop0' (ffff888083f6a6e0): fill_kobj_path: path = '/devices/virtual/block/loop0' __do_softirq+0x244/0x9a0 kernel/softirq.c:288 The buggy address belongs to the object at ffff8880a7773600 which belongs to the cache dentry of size 288 The buggy address is located 64 bytes inside of 288-byte region [ffff8880a7773600, ffff8880a7773720) kobject: 'queue' (ffff8880a0fba998): kobject_add_internal: parent: 'loop0', set: '' The buggy address belongs to the page: page:ffffea00029ddcc0 count:1 mapcount:0 mapping:ffff8880a7773080 index:0x0 flags: 0x1fffc0000000100(slab) raw: 01fffc0000000100 ffff8880a7773080 0000000000000000 000000010000000b raw: ffffea00029dcf20 ffffea00029ddfe0 ffff88821f8b5680 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: kobject: 'mq' (ffff8880a0fba9d8): kobject_add_internal: parent: 'loop0', set: '' ffff8880a7773500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880a7773580: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc >ffff8880a7773600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ kobject: 'mq' (ffff8880a0fba9d8): kobject_uevent_env ffff8880a7773680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a7773700: fb fb fb fb fc fc fc fc fc fc fc fc 00 00 00 00 ==================================================================