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BUG: KASAN: stack-out-of-bounds in hfcsusb_probe.cold+0x1a46/0x2682 drivers/isdn/hardware/mISDN/hfcsusb.c:1962
Read of size 4 at addr ffff8881cb6872f0 by task kworker/1:2/2011

CPU: 1 PID: 2011 Comm: kworker/1:2 Not tainted 5.2.0-rc6+ #15
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+0xca/0x13e lib/dump_stack.c:113
 print_address_description+0x67/0x231 mm/kasan/report.c:188
 __kasan_report.cold+0x1a/0x32 mm/kasan/report.c:317
 kasan_report+0xe/0x20 mm/kasan/common.c:614
 hfcsusb_probe.cold+0x1a46/0x2682 drivers/isdn/hardware/mISDN/hfcsusb.c:1962
 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
 really_probe+0x281/0x660 drivers/base/dd.c:509
 driver_probe_device+0x104/0x210 drivers/base/dd.c:670
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
 bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
 __device_attach+0x217/0x360 drivers/base/dd.c:843
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
 device_add+0xae6/0x16f0 drivers/base/core.c:2111
 usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023
 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
 usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266
 really_probe+0x281/0x660 drivers/base/dd.c:509
 driver_probe_device+0x104/0x210 drivers/base/dd.c:670
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
 bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
 __device_attach+0x217/0x360 drivers/base/dd.c:843
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
 device_add+0xae6/0x16f0 drivers/base/core.c:2111
 usb_new_device.cold+0x6a4/0xe61 drivers/usb/core/hub.c:2536
 hub_port_connect drivers/usb/core/hub.c:5098 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1abd/0x3550 drivers/usb/core/hub.c:5441
 process_one_work+0x905/0x1570 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
 kthread+0x30b/0x410 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the page:
page:ffffea00072da1c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x200000000000000()
raw: 0200000000000000 0000000000000000 ffffea00072da1c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881cb687180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881cb687200: 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1
>ffff8881cb687280: f1 f1 f1 01 f2 00 00 00 00 00 00 00 00 f3 f3 f3
                                                             ^
 ffff8881cb687300: f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881cb687380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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