Hello, syzbot found the following issue on: HEAD commit: 8010622c USB: UAS: introduce a quirk to set no_write_same 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=16dbc923500000 kernel config: https://syzkaller.appspot.com/x/.config?x=d24ee9ecd7ce968e dashboard link: https://syzkaller.appspot.com/bug?extid=930c00d27e58b0d77fb9 compiler: gcc (GCC) 10.1.0-syz 20200507 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+930c00d27e58b0d77fb9@xxxxxxxxxxxxxxxxxxxxxxxxx input: TeVii S662 as /devices/platform/dummy_hcd.3/usb4/4-1/rc/rc0/input610 dvb-usb: schedule remote query interval to 250 msecs. dw2102: su3000_power_ctrl: 0, initialized 1 dvb-usb: TeVii S662 successfully initialized and connected. usb 4-1: USB disconnect, device number 114 ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: null-ptr-deref in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] BUG: KASAN: null-ptr-deref in ida_free+0x186/0x2b0 lib/idr.c:510 Read of size 8 at addr 0000000000000018 by task kworker/1:0/4637 CPU: 1 PID: 4637 Comm: kworker/1:0 Not tainted 5.10.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:118 __kasan_report mm/kasan/report.c:549 [inline] kasan_report.cold+0x5/0x37 mm/kasan/report.c:562 check_memory_region_inline mm/kasan/generic.c:186 [inline] check_memory_region+0x13d/0x180 mm/kasan/generic.c:192 instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] ida_free+0x186/0x2b0 lib/idr.c:510 __media_device_unregister_entity+0x70/0x300 drivers/media/mc/mc-device.c:586 media_device_unregister_entity+0x49/0x70 drivers/media/mc/mc-device.c:689 dvb_media_device_free+0x1d5/0x620 drivers/media/dvb-core/dvbdev.c:226 dvb_remove_device.part.0+0x9c/0x260 drivers/media/dvb-core/dvbdev.c:561 dvb_remove_device drivers/media/dvb-core/dvbdev.c:554 [inline] dvb_unregister_device+0x1b/0x60 drivers/media/dvb-core/dvbdev.c:583 dvb_dmxdev_release+0x1a0/0x640 drivers/media/dvb-core/dmxdev.c:1459 dvb_usb_adapter_dvb_exit+0x93/0x230 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:224 dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:114 [inline] dvb_usb_exit.isra.0+0xb4/0x310 drivers/media/usb/dvb-usb/dvb-usb-init.c:129 dvb_usb_device_exit+0x111/0x1a0 drivers/media/usb/dvb-usb/dvb-usb-init.c:306 usb_unbind_interface+0x1d8/0x8d0 drivers/usb/core/driver.c:458 __device_release_driver+0x3bd/0x6f0 drivers/base/dd.c:1154 device_release_driver_internal drivers/base/dd.c:1185 [inline] device_release_driver+0x26/0x40 drivers/base/dd.c:1208 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533 device_del+0x502/0xec0 drivers/base/core.c:3115 usb_disable_device+0x35b/0x7b0 drivers/usb/core/message.c:1413 usb_disconnect.cold+0x27d/0x780 drivers/usb/core/hub.c:2218 hub_port_connect drivers/usb/core/hub.c:5074 [inline] hub_port_connect_change drivers/usb/core/hub.c:5363 [inline] port_event drivers/usb/core/hub.c:5509 [inline] hub_event+0x1c8a/0x42d0 drivers/usb/core/hub.c:5591 process_one_work+0x933/0x1520 kernel/workqueue.c:2272 process_scheduled_works kernel/workqueue.c:2334 [inline] worker_thread+0x82b/0x1120 kernel/workqueue.c:2420 kthread+0x38c/0x460 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 ================================================================== --- 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.
