(null): failure reading functionality i2c i2c-0: failure reading functionality i2c i2c-0: connected i2c-tiny-usb device usb 4-1: USB disconnect, device number 2 ================================================================== BUG: KASAN: use-after-free in kobject_put+0x296/0x2f0 lib/kobject.c:745 Read of size 1 at addr ffff88808c01d054 by task kworker/0:2/2494 CPU: 0 PID: 2494 Comm: kworker/0:2 Not tainted 5.7.0-rc6-next-20200522-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+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 kobject_put+0x296/0x2f0 lib/kobject.c:745 put_device+0x1b/0x30 drivers/base/core.c:2761 i2cdev_detach_adapter.part.0+0x53/0x70 drivers/i2c/i2c-dev.c:689 i2cdev_detach_adapter drivers/i2c/i2c-dev.c:647 [inline] i2cdev_notifier_call+0xad/0xc0 drivers/i2c/i2c-dev.c:704 notifier_call_chain+0xc0/0x230 kernel/notifier.c:83 __blocking_notifier_call_chain kernel/notifier.c:284 [inline] __blocking_notifier_call_chain kernel/notifier.c:271 [inline] blocking_notifier_call_chain kernel/notifier.c:295 [inline] blocking_notifier_call_chain+0x85/0xa0 kernel/notifier.c:292 device_del+0x17e/0xd30 drivers/base/core.c:2813 device_unregister+0x11/0x30 drivers/base/core.c:2871 i2c_del_adapter drivers/i2c/i2c-core-base.c:1671 [inline] i2c_del_adapter+0x42b/0x590 drivers/i2c/i2c-core-base.c:1610 i2c_tiny_usb_disconnect+0x3a/0xb0 drivers/i2c/busses/i2c-tiny-usb.c:283 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:436 __device_release_driver drivers/base/dd.c:1113 [inline] device_release_driver_internal+0x432/0x500 drivers/base/dd.c:1144 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:533 device_del+0x481/0xd30 drivers/base/core.c:2839 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1245 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2217 hub_port_connect drivers/usb/core/hub.c:5059 [inline] hub_port_connect_change drivers/usb/core/hub.c:5348 [inline] port_event drivers/usb/core/hub.c:5494 [inline] hub_event+0x17ca/0x38f0 drivers/usb/core/hub.c:5576 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268 process_scheduled_works kernel/workqueue.c:2330 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2416 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Allocated by task 2494: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc mm/kasan/common.c:494 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467 kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551 kmalloc include/linux/slab.h:555 [inline] kzalloc include/linux/slab.h:669 [inline] get_free_i2c_dev drivers/i2c/i2c-dev.c:76 [inline] i2cdev_attach_adapter.part.0+0x9a/0x3f0 drivers/i2c/i2c-dev.c:651 i2cdev_attach_adapter drivers/i2c/i2c-dev.c:647 [inline] i2cdev_notifier_call drivers/i2c/i2c-dev.c:702 [inline] i2cdev_notifier_call+0x9b/0xc0 drivers/i2c/i2c-dev.c:695 notifier_call_chain+0xc0/0x230 kernel/notifier.c:83 __blocking_notifier_call_chain kernel/notifier.c:284 [inline] __blocking_notifier_call_chain kernel/notifier.c:271 [inline] blocking_notifier_call_chain kernel/notifier.c:295 [inline] blocking_notifier_call_chain+0x85/0xa0 kernel/notifier.c:292 device_add+0xa6e/0x1900 drivers/base/core.c:2640 i2c_register_adapter+0x30d/0xb00 drivers/i2c/i2c-core-base.c:1415 i2c_add_adapter+0xba/0x100 drivers/i2c/i2c-core-base.c:1528 i2c_tiny_usb_probe+0x3a8/0x528 drivers/i2c/busses/i2c-tiny-usb.c:265 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:374 really_probe+0x281/0x6d0 drivers/base/dd.c:525 driver_probe_device+0xfe/0x1d0 drivers/base/dd.c:701 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:807 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x21a/0x360 drivers/base/dd.c:873 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xaf1/0x1900 drivers/base/core.c:2662 usb_set_configuration+0xec5/0x1740 drivers/usb/core/message.c:2032 usb_generic_driver_probe+0x9d/0xe0 drivers/usb/core/generic.c:241 usb_probe_device+0xc6/0x1f0 drivers/usb/core/driver.c:272 really_probe+0x281/0x6d0 drivers/base/dd.c:525 driver_probe_device+0xfe/0x1d0 drivers/base/dd.c:701 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:807 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x21a/0x360 drivers/base/dd.c:873 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xaf1/0x1900 drivers/base/core.c:2662 usb_new_device.cold+0x753/0x103d drivers/usb/core/hub.c:2554 hub_port_connect drivers/usb/core/hub.c:5208 [inline] hub_port_connect_change drivers/usb/core/hub.c:5348 [inline] port_event drivers/usb/core/hub.c:5494 [inline] hub_event+0x1eca/0x38f0 drivers/usb/core/hub.c:5576 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Freed by task 2494: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kfree+0x109/0x2b0 mm/slab.c:3757 device_release+0x71/0x200 drivers/base/core.c:1541 kobject_cleanup lib/kobject.c:701 [inline] kobject_release lib/kobject.c:732 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c8/0x2f0 lib/kobject.c:749 cdev_device_del+0x69/0x80 fs/char_dev.c:575 put_i2c_dev+0x160/0x1b0 drivers/i2c/i2c-dev.c:93 i2cdev_detach_adapter.part.0+0x53/0x70 drivers/i2c/i2c-dev.c:689 i2cdev_detach_adapter drivers/i2c/i2c-dev.c:647 [inline] i2cdev_notifier_call+0xad/0xc0 drivers/i2c/i2c-dev.c:704 notifier_call_chain+0xc0/0x230 kernel/notifier.c:83 __blocking_notifier_call_chain kernel/notifier.c:284 [inline] __blocking_notifier_call_chain kernel/notifier.c:271 [inline] blocking_notifier_call_chain kernel/notifier.c:295 [inline] blocking_notifier_call_chain+0x85/0xa0 kernel/notifier.c:292 device_del+0x17e/0xd30 drivers/base/core.c:2813 device_unregister+0x11/0x30 drivers/base/core.c:2871 i2c_del_adapter drivers/i2c/i2c-core-base.c:1671 [inline] i2c_del_adapter+0x42b/0x590 drivers/i2c/i2c-core-base.c:1610 i2c_tiny_usb_disconnect+0x3a/0xb0 drivers/i2c/busses/i2c-tiny-usb.c:283 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:436 __device_release_driver drivers/base/dd.c:1113 [inline] device_release_driver_internal+0x432/0x500 drivers/base/dd.c:1144 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:533 device_del+0x481/0xd30 drivers/base/core.c:2839 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1245 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2217 hub_port_connect drivers/usb/core/hub.c:5059 [inline] hub_port_connect_change drivers/usb/core/hub.c:5348 [inline] port_event drivers/usb/core/hub.c:5494 [inline] hub_event+0x17ca/0x38f0 drivers/usb/core/hub.c:5576 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268 process_scheduled_works kernel/workqueue.c:2330 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2416 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 The buggy address belongs to the object at ffff88808c01d000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 84 bytes inside of 2048-byte region [ffff88808c01d000, ffff88808c01d800) The buggy address belongs to the page: page:ffffea0002300740 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0002300708 ffffea000277c788 ffff8880aa000e00 raw: 0000000000000000 ffff88808c01d000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808c01cf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808c01cf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88808c01d000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88808c01d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808c01d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================