sp0: Synchronizing with TNC sp0: Found TNC ================================================================== BUG: KASAN: use-after-free in debugfs_remove+0x10d/0x130 fs/debugfs/inode.c:687 Read of size 8 at addr ffff888092d2b460 by task syz-executor.4/10969 CPU: 0 PID: 10969 Comm: syz-executor.4 Not tainted 4.19.97-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 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_ioctl+0x239/0x300 kernel/trace/blktrace.c:730 blkdev_ioctl+0x126/0x1ab6 block/ioctl.c:587 block_ioctl+0xee/0x130 fs/block_dev.c:1894 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 RIP: 0033:0x45aff9 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f37bbe12c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f37bbe136d4 RCX: 000000000045aff9 RDX: 000000000000ff00 RSI: 0000000000001276 RDI: 0000000000000006 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000226 R14: 00000000004c2bb0 R15: 000000000075bfd4 Allocated by task 10934: 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+0x126/0x1ab6 block/ioctl.c:587 block_ioctl+0xee/0x130 fs/block_dev.c:1894 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 10949: 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 ffff888092d2b420 which belongs to the cache dentry(49:syz2) of size 288 The buggy address is located 64 bytes inside of 288-byte region [ffff888092d2b420, ffff888092d2b540) The buggy address belongs to the page: page:ffffea00024b4ac0 count:1 mapcount:0 mapping:ffff88808b28fdc0 index:0xffff888092d2bdc0 flags: 0xfffe0000000100(slab) raw: 00fffe0000000100 ffffea0002220788 ffffea0002519588 ffff88808b28fdc0 raw: ffff888092d2bdc0 ffff888092d2b000 000000010000000a ffff88804d174e80 page dumped because: kasan: bad access detected page->mem_cgroup:ffff88804d174e80 Memory state around the buggy address: ffff888092d2b300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888092d2b380: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff888092d2b400: fc fc fc fc fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888092d2b480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888092d2b500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================