usb 2-1: USB disconnect, device number 20
asix 2-1:0.0 eth5: unregister 'asix' usb-dummy_hcd.1-1, ASIX AX88178 USB 2.0 Ethernet
==================================================================
BUG: KASAN: null-ptr-deref in phy_is_started include/linux/phy.h:947 [inline]
BUG: KASAN: null-ptr-deref in phy_disconnect+0x22/0xac drivers/net/phy/phy_device.c:1097
Read of size 4 at addr 0000000000000570 by task kworker/0:6/3749

CPU: 0 PID: 3749 Comm: kworker/0:6 Not tainted 5.14.0-rc1-syzkaller-00005-g867432bec1c6 #0
Hardware name: riscv-virtio,qemu (DT)
Workqueue: usb_hub_wq hub_event
Call Trace:
[<ffffffff80009524>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:112
==================================================================
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000570
Oops [#1]
Modules linked in:
CPU: 0 PID: 3749 Comm: kworker/0:6 Tainted: G    B             5.14.0-rc1-syzkaller-00005-g867432bec1c6 #0
Hardware name: riscv-virtio,qemu (DT)
Workqueue: usb_hub_wq hub_event
epc : phy_is_started include/linux/phy.h:947 [inline]
epc : phy_disconnect+0x22/0xac drivers/net/phy/phy_device.c:1097
 ra : phy_is_started include/linux/phy.h:947 [inline]
 ra : phy_disconnect+0x22/0xac drivers/net/phy/phy_device.c:1097
epc : ffffffff81340410 ra : ffffffff81340410 sp : ffffffe0109477c0
 gp : ffffffff83f95bc8 tp : ffffffe008af97c0 t0 : ffffffe00acefac0
 t1 : ffffffc40163af87 t2 : 0000003fffb3e1d7 s0 : ffffffe0109477e0
 s1 : 0000000000000000 a0 : 0000000000000001 a1 : 0000000000000007
 a2 : 1ffffffc0115f2f8 a3 : ffffffff82b9a282 a4 : 0000000000000000
 a5 : ffffffe008afa7c0 a6 : 0000000000f00000 a7 : ffffffe00b1d7c3f
 s2 : ffffffe029af0ba0 s3 : ffffffe0295b5d80 s4 : ffffffff831f4678
 s5 : ffffffe029af0d08 s6 : ffffffe029af0b90 s7 : ffffffe007e58700
 s8 : ffffffe029af0000 s9 : ffffffff8374ffb0 s10: ffffffe00f9c2030
 s11: 0000000000000000 t3 : 0000000000000000 t4 : ffffffc40163af87
 t5 : ffffffc40163af88 t6 : 0000000000000002
status: 0000000000000120 badaddr: 0000000000000570 cause: 000000000000000d
[<ffffffff81340410>] phy_is_started include/linux/phy.h:947 [inline]
[<ffffffff81340410>] phy_disconnect+0x22/0xac drivers/net/phy/phy_device.c:1097
[<ffffffff814f1b4a>] ax88772_unbind+0x42/0x60 drivers/net/usb/asix_devices.c:815
[<ffffffff81518602>] usbnet_disconnect+0xa8/0x1fc drivers/net/usb/usbnet.c:1618
[<ffffffff815c73e8>] usb_unbind_interface+0x13c/0x526 drivers/usb/core/driver.c:458
[<ffffffff80fd550c>] __device_release_driver+0x29c/0x3e0 drivers/base/dd.c:1201
[<ffffffff80fd567e>] device_release_driver_internal drivers/base/dd.c:1232 [inline]
[<ffffffff80fd567e>] device_release_driver+0x2e/0x44 drivers/base/dd.c:1255
[<ffffffff80fd3e86>] bus_remove_device+0x1d4/0x2dc drivers/base/bus.c:529
[<ffffffff80fc932a>] device_del+0x2da/0x6ec drivers/base/core.c:3540
[<ffffffff815c2d28>] usb_disable_device+0x216/0x436 drivers/usb/core/message.c:1419
[<ffffffff815aca6e>] usb_disconnect+0x20e/0x4e2 drivers/input/misc/yealink.c:335
[<ffffffff815b2658>] hub_port_connect drivers/usb/core/hub.c:5151 [inline]
[<ffffffff815b2658>] hub_port_connect_change drivers/usb/core/hub.c:5440 [inline]
[<ffffffff815b2658>] port_event drivers/usb/core/hub.c:5586 [inline]
[<ffffffff815b2658>] hub_event+0x2172/0x3068 drivers/usb/core/hub.c:5668
[<ffffffff80063906>] process_one_work+0x5e0/0xf82 kernel/workqueue.c:2276
[<ffffffff800647a0>] process_scheduled_works kernel/workqueue.c:2338 [inline]
[<ffffffff800647a0>] worker_thread+0x4f8/0x8e6 kernel/workqueue.c:2424
[<ffffffff800762f8>] kthread+0x25c/0x2c6 kernel/kthread.c:319
[<ffffffff8000515e>] ret_from_exception+0x0/0x14
---[ end trace 317285a3e8f045f4 ]---