Hello, syzbot found the following issue on: HEAD commit: 8404c9fb Merge branch 'akpm' (patches from Andrew) git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing console output: https://syzkaller.appspot.com/x/log.txt?x=11fffd2dd00000 kernel config: https://syzkaller.appspot.com/x/.config?x=a73b8d06863cd18d dashboard link: https://syzkaller.appspot.com/bug?extid=7da71853830ac3289474 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7da71853830ac3289474@xxxxxxxxxxxxxxxxxxxxxxxxx usb 6-1: USB disconnect, device number 39 ------------[ cut here ]------------ ODEBUG: free active (active state 0) object type: work_struct hint: service_interrupt_work+0x0/0x110 arch/x86/include/asm/bitops.h:207 WARNING: CPU: 0 PID: 9431 at lib/debugobjects.c:505 debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Modules linked in: CPU: 0 PID: 9431 Comm: kworker/0:7 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event RIP: 0010:debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Code: ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 af 00 00 00 48 8b 14 dd 40 eb 1f 86 4c 89 ee 48 c7 c7 40 df 1f 86 e8 69 d1 89 03 <0f> 0b 83 05 b5 8e ce 06 01 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e c3 RSP: 0018:ffffc9001264f650 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff812a3e73 RDI: fffff520024c9ebc RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: ffffffff814b72cb R11: 0000000000000000 R12: ffffffff860687c0 R13: ffffffff861fe580 R14: ffffffff811a2280 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4be635d000 CR3: 0000000117b90000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:987 [inline] debug_check_no_obj_freed+0x301/0x420 lib/debugobjects.c:1018 slab_free_hook mm/slub.c:1556 [inline] slab_free_freelist_hook+0x13b/0x1b0 mm/slub.c:1606 slab_free mm/slub.c:3166 [inline] kfree+0xdb/0x3b0 mm/slub.c:4225 wdm_disconnect+0x3bd/0x450 drivers/usb/class/cdc-wdm.c:1052 usb_unbind_interface+0x1d8/0x8d0 drivers/usb/core/driver.c:458 __device_release_driver+0x3bd/0x6f0 drivers/base/dd.c:1181 device_release_driver_internal drivers/base/dd.c:1212 [inline] device_release_driver+0x26/0x40 drivers/base/dd.c:1235 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533 device_del+0x502/0xd40 drivers/base/core.c:3507 usb_disable_device+0x35b/0x7b0 drivers/usb/core/message.c:1413 usb_disconnect.cold+0x27d/0x791 drivers/usb/core/hub.c:2219 hub_port_connect drivers/usb/core/hub.c:5127 [inline] hub_port_connect_change drivers/usb/core/hub.c:5416 [inline] port_event drivers/usb/core/hub.c:5562 [inline] hub_event+0x1c9c/0x4320 drivers/usb/core/hub.c:5644 process_one_work+0x98d/0x1580 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x38c/0x460 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
