Unknown ioctl 19462 ================================================================== BUG: KASAN: use-after-free in kobject_put+0xcb/0xe0 lib/kobject.c:704 Read of size 1 at addr ffff880181f9a44c by task syz-executor2/13117 CPU: 0 PID: 13117 Comm: syz-executor2 Not tainted 4.20.0-rc1-next-20181109+ #110 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+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 kobject_put+0xcb/0xe0 lib/kobject.c:704 put_device+0x20/0x30 drivers/base/core.c:2024 hci_free_dev+0x19/0x20 net/bluetooth/hci_core.c:3208 vhci_release+0x7e/0xf0 drivers/bluetooth/hci_vhci.c:355 __fput+0x3bc/0xa70 fs/file_table.c:279 ____fput+0x15/0x20 fs/file_table.c:312 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x411021 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 19 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffdae4f4890 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000411021 RDX: 0000000000000000 RSI: 0000000000734d00 RDI: 0000000000000005 RBP: 0000000000000000 R08: ffffffff8185cb99 R09: 00000000288a7cb6 R10: 00007ffdae4f47c0 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 00000000000000c0 R15: 0000000000000002 Allocated by task 13129: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620 kmalloc include/linux/slab.h:546 [inline] kzalloc include/linux/slab.h:741 [inline] hci_alloc_dev+0x228/0x21a0 net/bluetooth/hci_core.c:3116 __vhci_create_device+0x102/0x580 drivers/bluetooth/hci_vhci.c:114 vhci_create_device drivers/bluetooth/hci_vhci.c:163 [inline] vhci_get_user drivers/bluetooth/hci_vhci.c:219 [inline] vhci_write+0x2de/0x470 drivers/bluetooth/hci_vhci.c:299 call_write_iter include/linux/fs.h:1867 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x6b8/0x9f0 fs/read_write.c:487 vfs_write+0x1fc/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 13117: save_stack+0x43/0xd0 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:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 bt_host_release+0x19/0x30 net/bluetooth/hci_sysfs.c:86 device_release+0x7e/0x210 drivers/base/core.c:891 kobject_cleanup lib/kobject.c:662 [inline] kobject_release lib/kobject.c:691 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put.cold.9+0x287/0x2e4 lib/kobject.c:708 put_device+0x20/0x30 drivers/base/core.c:2024 hci_dev_put include/net/bluetooth/hci_core.h:1014 [inline] hci_unregister_dev+0x71d/0x990 net/bluetooth/hci_core.c:3379 vhci_release+0x76/0xf0 drivers/bluetooth/hci_vhci.c:354 __fput+0x3bc/0xa70 fs/file_table.c:279 ____fput+0x15/0x20 fs/file_table.c:312 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff880181f99380 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 4300 bytes inside of 8192-byte region [ffff880181f99380, ffff880181f9b380) The buggy address belongs to the page: page:ffffea000607e600 count:1 mapcount:0 mapping:ffff8801da802080 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000010200(slab|head) raw: 02fffc0000010200 ffffea000608b708 ffffea0006053408 ffff8801da802080 raw: 0000000000000000 ffff880181f99380 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff880181f9a300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff880181f9a380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff880181f9a400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff880181f9a480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff880181f9a500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Unknown ioctl 19462