================================================================== BUG: KASAN: use-after-free in debugfs_remove+0xfd/0x120 fs/debugfs/inode.c:687 Read of size 8 at addr ffff8880348b64a0 by task kworker/1:1/9807 CPU: 1 PID: 9807 Comm: kworker/1:1 Not tainted 4.19.111-syzkaller #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:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 print_address_description.cold+0x7c/0x212 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+0x88/0x2b9 mm/kasan/report.c:396 debugfs_remove+0xfd/0x120 fs/debugfs/inode.c:687 blk_trace_free+0x31/0x130 kernel/trace/blktrace.c:312 blk_trace_cleanup kernel/trace/blktrace.c:339 [inline] __blk_trace_remove+0x71/0xa0 kernel/trace/blktrace.c:352 blk_trace_shutdown+0x5f/0x80 kernel/trace/blktrace.c:752 __blk_release_queue+0x250/0x510 block/blk-sysfs.c:855 process_one_work+0x91f/0x1640 kernel/workqueue.c:2155 worker_thread+0x96/0xe20 kernel/workqueue.c:2298 kthread+0x34a/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Allocated by task 28609: set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc mm/kasan/kasan.c:553 [inline] kasan_kmalloc+0xbf/0xe0 mm/kasan/kasan.c:531 kmem_cache_alloc+0x127/0x710 mm/slab.c:3559 __d_alloc+0x2b/0x9e0 fs/dcache.c:1610 d_alloc+0x4a/0x240 fs/dcache.c:1694 d_alloc_parallel+0xe8/0x1ad0 fs/dcache.c:2441 __lookup_slow+0x18d/0x4b0 fs/namei.c:1655 lookup_one_len+0x163/0x190 fs/namei.c:2544 start_creating fs/debugfs/inode.c:313 [inline] start_creating+0xba/0x1f0 fs/debugfs/inode.c:289 __debugfs_create_file+0x62/0x400 fs/debugfs/inode.c:352 do_blk_trace_setup+0x361/0xb60 kernel/trace/blktrace.c:528 __blk_trace_setup+0xca/0x180 kernel/trace/blktrace.c:577 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. blk_trace_ioctl+0x15e/0x2e0 kernel/trace/blktrace.c:716 blkdev_ioctl+0x112/0x1a1c block/ioctl.c:587 block_ioctl+0xe9/0x130 fs/block_dev.c:1894 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=28652 comm=syz-executor.5 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9568: set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/kasan.c:521 __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x7f/0x260 mm/slab.c:3765 __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+0xb2d/0x17f0 kernel/rcu/tree.c:2881 __do_softirq+0x26c/0x93c kernel/softirq.c:292 The buggy address belongs to the object at ffff8880348b6460 which belongs to the cache dentry(49:syz2) of size 288 The buggy address is located 64 bytes inside of 288-byte region [ffff8880348b6460, ffff8880348b6580) The buggy address belongs to the page: page:ffffea0000d22d80 count:1 mapcount:0 mapping:ffff88808cc64780 index:0x0 flags: 0xfffe0000000100(slab) raw: 00fffe0000000100 ffffea0000d22d08 ffffea0000d22e48 ffff88808cc64780 raw: 0000000000000000 ffff8880348b6040 000000010000000b ffff888083d44580 page dumped because: kasan: bad access detected page->mem_cgroup:ffff888083d44580 Memory state around the buggy address: ffff8880348b6380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880348b6400: fb fb fb fb fc fc fc fc fc fc fc fc fb fb fb fb >ffff8880348b6480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880348b6500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880348b6580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================