usb 4-1: USB disconnect, device number 6
asix 4-1:0.0 eth1: unregister 'asix' usb-dummy_hcd.3-1, ASIX AX88172A USB 2.0 Ethernet
==================================================================
BUG: KASAN: use-after-free in ax88172a_remove_mdio drivers/net/usb/ax88172a.c:123 [inline]
BUG: KASAN: use-after-free in ax88172a_unbind+0x6a/0xc0 drivers/net/usb/ax88172a.c:274
Read of size 8 at addr ffff8881c4c96180 by task kworker/0:1/12

CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.4.41-syzkaller-00234-gb818fc58f06b #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+0x14a/0x1ce lib/dump_stack.c:118
 print_address_description+0x93/0x620 mm/kasan/report.c:374
 __kasan_report+0x16d/0x1e0 mm/kasan/report.c:506
 kasan_report+0x34/0x60 mm/kasan/common.c:634
 ax88172a_remove_mdio drivers/net/usb/ax88172a.c:123 [inline]
 ax88172a_unbind+0x6a/0xc0 drivers/net/usb/ax88172a.c:274
 usbnet_disconnect+0x14e/0x340 drivers/net/usb/usbnet.c:1618
 usb_unbind_interface+0x1d8/0x850 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1137 [inline]
 device_release_driver_internal+0x515/0x7b0 drivers/base/dd.c:1168
 bus_remove_device+0x2e7/0x350 drivers/base/bus.c:532
 device_del+0x7bc/0x1200 drivers/base/core.c:2684
 usb_disable_device+0x3f3/0xb80 drivers/usb/core/message.c:1244
 usb_disconnect+0x341/0x880 drivers/usb/core/hub.c:2216
 hub_port_connect drivers/usb/core/hub.c:4973 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5237 [inline]
 port_event drivers/usb/core/hub.c:5383 [inline]
 hub_event+0x1c6c/0x4fa0 drivers/usb/core/hub.c:5465
 process_one_work+0x777/0xf90 kernel/workqueue.c:2274
 worker_thread+0xa8f/0x1430 kernel/workqueue.c:2420
 kthread+0x2df/0x300 kernel/kthread.c:255
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Allocated by task 12:
 save_stack mm/kasan/common.c:69 [inline]
 set_track mm/kasan/common.c:77 [inline]
 __kasan_kmalloc+0x12c/0x1c0 mm/kasan/common.c:510
 kmem_cache_alloc_trace+0xc3/0x280 mm/slub.c:2793
 kmalloc include/linux/slab.h:556 [inline]
 kzalloc include/linux/slab.h:690 [inline]
 ax88172a_bind+0xc7/0x980 drivers/net/usb/ax88172a.c:191
 usbnet_probe+0xa9f/0x2770 drivers/net/usb/usbnet.c:1737
 usb_probe_interface+0x631/0xad0 drivers/usb/core/driver.c:361
 really_probe+0x764/0xf70 drivers/base/dd.c:555
 driver_probe_device+0xe6/0x230 drivers/base/dd.c:724
 bus_for_each_drv+0x17a/0x200 drivers/base/bus.c:430
 __device_attach+0x27b/0x420 drivers/base/dd.c:897
 bus_probe_device+0xbb/0x200 drivers/base/bus.c:490
 device_add+0x105a/0x1750 drivers/base/core.c:2507
 usb_set_configuration+0x184c/0x1dc0 drivers/usb/core/message.c:2030
 generic_probe+0x82/0x140 drivers/usb/core/generic.c:210
 really_probe+0x764/0xf70 drivers/base/dd.c:555
 driver_probe_device+0xe6/0x230 drivers/base/dd.c:724
 bus_for_each_drv+0x17a/0x200 drivers/base/bus.c:430
 __device_attach+0x27b/0x420 drivers/base/dd.c:897
 bus_probe_device+0xbb/0x200 drivers/base/bus.c:490
 device_add+0x105a/0x1750 drivers/base/core.c:2507
 usb_new_device+0xda7/0x1710 drivers/usb/core/hub.c:2553
 hub_port_connect drivers/usb/core/hub.c:5122 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5237 [inline]
 port_event drivers/usb/core/hub.c:5383 [inline]
 hub_event+0x2963/0x4fa0 drivers/usb/core/hub.c:5465
 process_one_work+0x777/0xf90 kernel/workqueue.c:2274
 worker_thread+0xa8f/0x1430 kernel/workqueue.c:2420
 kthread+0x2df/0x300 kernel/kthread.c:255
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Freed by task 12:
 save_stack mm/kasan/common.c:69 [inline]
 set_track mm/kasan/common.c:77 [inline]
 kasan_set_free_info mm/kasan/common.c:332 [inline]
 __kasan_slab_free+0x181/0x230 mm/kasan/common.c:471
 slab_free_hook mm/slub.c:1424 [inline]
 slab_free_freelist_hook+0xd0/0x150 mm/slub.c:1457
 slab_free mm/slub.c:3014 [inline]
 kfree+0x12b/0x600 mm/slub.c:3975
 ax88172a_bind+0x844/0x980 drivers/net/usb/ax88172a.c:250
 usbnet_probe+0xa9f/0x2770 drivers/net/usb/usbnet.c:1737
 usb_probe_interface+0x631/0xad0 drivers/usb/core/driver.c:361
 really_probe+0x764/0xf70 drivers/base/dd.c:555
 driver_probe_device+0xe6/0x230 drivers/base/dd.c:724
 bus_for_each_drv+0x17a/0x200 drivers/base/bus.c:430
 __device_attach+0x27b/0x420 drivers/base/dd.c:897
 bus_probe_device+0xbb/0x200 drivers/base/bus.c:490
 device_add+0x105a/0x1750 drivers/base/core.c:2507
 usb_set_configuration+0x184c/0x1dc0 drivers/usb/core/message.c:2030
 generic_probe+0x82/0x140 drivers/usb/core/generic.c:210
 really_probe+0x764/0xf70 drivers/base/dd.c:555
 driver_probe_device+0xe6/0x230 drivers/base/dd.c:724
 bus_for_each_drv+0x17a/0x200 drivers/base/bus.c:430
 __device_attach+0x27b/0x420 drivers/base/dd.c:897
 bus_probe_device+0xbb/0x200 drivers/base/bus.c:490
 device_add+0x105a/0x1750 drivers/base/core.c:2507
 usb_new_device+0xda7/0x1710 drivers/usb/core/hub.c:2553
 hub_port_connect drivers/usb/core/hub.c:5122 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5237 [inline]
 port_event drivers/usb/core/hub.c:5383 [inline]
 hub_event+0x2963/0x4fa0 drivers/usb/core/hub.c:5465
 process_one_work+0x777/0xf90 kernel/workqueue.c:2274
 worker_thread+0xa8f/0x1430 kernel/workqueue.c:2420
 kthread+0x2df/0x300 kernel/kthread.c:255
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff8881c4c96180
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 0 bytes inside of
 64-byte region [ffff8881c4c96180, ffff8881c4c961c0)
The buggy address belongs to the page:
page:ffffea0007132580 refcount:1 mapcount:0 mapping:ffff8881da803180 index:0x0
flags: 0x8000000000000200(slab)
raw: 8000000000000200 ffffea000712a640 0000001900000019 ffff8881da803180
raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881c4c96080: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8881c4c96100: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff8881c4c96180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                   ^
 ffff8881c4c96200: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8881c4c96280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================
kernel BUG at drivers/net/phy/mdio_bus.c:456!
CPU: 0 PID: 12 Comm: kworker/0:1 Tainted: G    B             5.4.41-syzkaller-00234-gb818fc58f06b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
RIP: 0010:mdiobus_unregister+0x1da/0x1e0 drivers/net/phy/mdio_bus.c:456
Code: f5 fe e9 80 fe ff ff 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 94 fe ff ff 4c 89 ff e8 90 5e f5 fe e9 87 fe ff ff e8 66 32 c7 fe <0f> 0b 0f 1f 40 00 41 57 41 56 41 55 41 54 53 49 89 ff 49 bc 00 00
RSP: 0018:ffff8881da9df620 EFLAGS: 00010246
RAX: ffffffff827abf4a RBX: 0000000000000000 RCX: 0000000000040000
RDX: ffffc9000d0c8000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: 1ffff110333e5453 R08: ffffffff827abdb6 R09: ffffed103b705df0
R10: ffffed103b705df0 R11: 0000000000000000 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff888199f2a200 R15: ffff888199f2a298
FS:  0000000000000000(0000) GS:ffff8881db800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffccf698c18 CR3: 000000019ce39006 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ax88172a_remove_mdio drivers/net/usb/ax88172a.c:124 [inline]
 ax88172a_unbind+0x99/0xc0 drivers/net/usb/ax88172a.c:274
 usbnet_disconnect+0x14e/0x340 drivers/net/usb/usbnet.c:1618
 usb_unbind_interface+0x1d8/0x850 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1137 [inline]
 device_release_driver_internal+0x515/0x7b0 drivers/base/dd.c:1168
 bus_remove_device+0x2e7/0x350 drivers/base/bus.c:532
 device_del+0x7bc/0x1200 drivers/base/core.c:2684
 usb_disable_device+0x3f3/0xb80 drivers/usb/core/message.c:1244
 usb_disconnect+0x341/0x880 drivers/usb/core/hub.c:2216
 hub_port_connect drivers/usb/core/hub.c:4973 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5237 [inline]
 port_event drivers/usb/core/hub.c:5383 [inline]
 hub_event+0x1c6c/0x4fa0 drivers/usb/core/hub.c:5465
 process_one_work+0x777/0xf90 kernel/workqueue.c:2274
 worker_thread+0xa8f/0x1430 kernel/workqueue.c:2420
 kthread+0x2df/0x300 kernel/kthread.c:255
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
Modules linked in:
RIP: 0010:mdiobus_unregister+0x1da/0x1e0 drivers/net/phy/mdio_bus.c:456
Code: f5 fe e9 80 fe ff ff 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 94 fe ff ff 4c 89 ff e8 90 5e f5 fe e9 87 fe ff ff e8 66 32 c7 fe <0f> 0b 0f 1f 40 00 41 57 41 56 41 55 41 54 53 49 89 ff 49 bc 00 00
RSP: 0018:ffff8881da9df620 EFLAGS: 00010246
RAX: ffffffff827abf4a RBX: 0000000000000000 RCX: 0000000000040000
RDX: ffffc9000d0c8000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: 1ffff110333e5453 R08: ffffffff827abdb6 R09: ffffed103b705df0
R10: ffffed103b705df0 R11: 0000000000000000 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff888199f2a200 R15: ffff888199f2a298
FS:  0000000000000000(0000) GS:ffff8881db800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd33845e000 CR3: 00000001c7d39001 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400