In the Linux kernel, the following vulnerability has been resolved:

usb: misc: usbio: fix disconnect UAF in client teardown

usbio_disconnect() walks usbio->cli_list in reverse and uninitializes each
auxiliary device. auxiliary_device_uninit() drops the device reference, and
for an unbound child that can run usbio_auxdev_release() and free the
containing struct usbio_client.

list_for_each_entry_reverse() advances after the loop body by reading
client->link.prev. If the current client is freed by
auxiliary_device_uninit(), the iterator dereferences freed memory.

Use list_for_each_entry_safe_reverse() so the previous client is
cached before the body can drop the final reference. This preserves
reverse teardown order while keeping the next iterator cursor independent
of the current client's lifetime.

Validation reproduced this kernel report:
BUG: KASAN: slab-use-after-free in usbio_disconnect+0x12e/0x150

Call Trace:
<TASK>
dump_stack_lvl+0x66/0xa0
print_report+0xce/0x630
? usbio_disconnect+0x12e/0x150
? srso_alias_return_thunk+0x5/0xfbef5
? __virt_addr_valid+0x188/0x320
? usbio_disconnect+0x12e/0x150
kasan_report+0xe0/0x110
? usbio_disconnect+0x12e/0x150
usbio_disconnect+0x12e/0x150
usb_unbind_interface+0xf3/0x400
really_probe+0x316/0x660
__driver_probe_device+0x106/0x240
driver_probe_device+0x4a/0x110
__device_attach_driver+0xf1/0x1a0
? __pfx___device_attach_driver+0x10/0x10
bus_for_each_drv+0xf9/0x160
? __pfx_bus_for_each_drv+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? trace_hardirqs_on+0x18/0x130
? srso_alias_return_thunk+0x5/0xfbef5
? _raw_spin_unlock_irqrestore+0x44/0x60
__device_attach+0x133/0x2a0
? __pfx___device_attach+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? do_raw_spin_unlock+0x9a/0x100
? srso_alias_return_thunk+0x5/0xfbef5
device_initial_probe+0x55/0x70
bus_probe_device+0x4a/0xd0
device_add+0x9b9/0xc10
? __pfx_device_add+0x10/0x10
? _raw_spin_unlock_irqrestore+0x44/0x60
? srso_alias_return_thunk+0x5/0xfbef5
? lockdep_hardirqs_on_prepare+0xea/0x1a0
? srso_alias_return_thunk+0x5/0xfbef5
? usb_enable_lpm+0x3c/0x260
usb_set_configuration+0xb64/0xf20
usb_generic_driver_probe+0x5f/0x90
usb_probe_device+0x71/0x1b0
really_probe+0x46b/0x660
__driver_probe_device+0x106/0x240
driver_probe_device+0x4a/0x110
__device_attach_driver+0xf1/0x1a0
? __pfx___device_attach_driver+0x10/0x10
bus_for_each_drv+0xf9/0x160
? __pfx_bus_for_each_drv+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? trace_hardirqs_on+0x18/0x130
? srso_alias_return_thunk+0x5/0xfbef5
? _raw_spin_unlock_irqrestore+0x44/0x60
__device_attach+0x133/0x2a0
? __pfx___device_attach+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? do_raw_spin_unlock+0x9a/0x100
? srso_alias_return_thunk+0x5/0xfbef5
device_initial_probe+0x55/0x70
bus_probe_device+0x4a/0xd0
device_add+0x9b9/0xc10
? __pfx_device_add+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? add_device_randomness+0xb7/0xf0
usb_new_device+0x492/0x870
hub_event+0x1b10/0x29c0
? __pfx_hub_event+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? lock_acquire+0x187/0x300
? process_one_work+0x475/0xb90
? srso_alias_return_thunk+0x5/0xfbef5
? lock_release+0xc8/0x290
? srso_alias_return_thunk+0x5/0xfbef5
process_one_work+0x4d7/0xb90
? __pfx_process_one_work+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? srso_alias_return_thunk+0x5/0xfbef5
? __list_add_valid_or_report+0x37/0xf0
? __pfx_hub_event+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
worker_thread+0x2d8/0x570
? __pfx_worker_thread+0x10/0x10
kthread+0x1ad/0x1f0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x3c9/0x540
? __pfx_ret_from_fork+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? __switch_to+0x2e9/0x730
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>

Project Subscriptions

Vendors Products
Linux Kernel Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Sat, 25 Jul 2026 09:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: usb: misc: usbio: fix disconnect UAF in client teardown usbio_disconnect() walks usbio->cli_list in reverse and uninitializes each auxiliary device. auxiliary_device_uninit() drops the device reference, and for an unbound child that can run usbio_auxdev_release() and free the containing struct usbio_client. list_for_each_entry_reverse() advances after the loop body by reading client->link.prev. If the current client is freed by auxiliary_device_uninit(), the iterator dereferences freed memory. Use list_for_each_entry_safe_reverse() so the previous client is cached before the body can drop the final reference. This preserves reverse teardown order while keeping the next iterator cursor independent of the current client's lifetime. Validation reproduced this kernel report: BUG: KASAN: slab-use-after-free in usbio_disconnect+0x12e/0x150 Call Trace: <TASK> dump_stack_lvl+0x66/0xa0 print_report+0xce/0x630 ? usbio_disconnect+0x12e/0x150 ? srso_alias_return_thunk+0x5/0xfbef5 ? __virt_addr_valid+0x188/0x320 ? usbio_disconnect+0x12e/0x150 kasan_report+0xe0/0x110 ? usbio_disconnect+0x12e/0x150 usbio_disconnect+0x12e/0x150 usb_unbind_interface+0xf3/0x400 really_probe+0x316/0x660 __driver_probe_device+0x106/0x240 driver_probe_device+0x4a/0x110 __device_attach_driver+0xf1/0x1a0 ? __pfx___device_attach_driver+0x10/0x10 bus_for_each_drv+0xf9/0x160 ? __pfx_bus_for_each_drv+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? trace_hardirqs_on+0x18/0x130 ? srso_alias_return_thunk+0x5/0xfbef5 ? _raw_spin_unlock_irqrestore+0x44/0x60 __device_attach+0x133/0x2a0 ? __pfx___device_attach+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? do_raw_spin_unlock+0x9a/0x100 ? srso_alias_return_thunk+0x5/0xfbef5 device_initial_probe+0x55/0x70 bus_probe_device+0x4a/0xd0 device_add+0x9b9/0xc10 ? __pfx_device_add+0x10/0x10 ? _raw_spin_unlock_irqrestore+0x44/0x60 ? srso_alias_return_thunk+0x5/0xfbef5 ? lockdep_hardirqs_on_prepare+0xea/0x1a0 ? srso_alias_return_thunk+0x5/0xfbef5 ? usb_enable_lpm+0x3c/0x260 usb_set_configuration+0xb64/0xf20 usb_generic_driver_probe+0x5f/0x90 usb_probe_device+0x71/0x1b0 really_probe+0x46b/0x660 __driver_probe_device+0x106/0x240 driver_probe_device+0x4a/0x110 __device_attach_driver+0xf1/0x1a0 ? __pfx___device_attach_driver+0x10/0x10 bus_for_each_drv+0xf9/0x160 ? __pfx_bus_for_each_drv+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? trace_hardirqs_on+0x18/0x130 ? srso_alias_return_thunk+0x5/0xfbef5 ? _raw_spin_unlock_irqrestore+0x44/0x60 __device_attach+0x133/0x2a0 ? __pfx___device_attach+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? do_raw_spin_unlock+0x9a/0x100 ? srso_alias_return_thunk+0x5/0xfbef5 device_initial_probe+0x55/0x70 bus_probe_device+0x4a/0xd0 device_add+0x9b9/0xc10 ? __pfx_device_add+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? add_device_randomness+0xb7/0xf0 usb_new_device+0x492/0x870 hub_event+0x1b10/0x29c0 ? __pfx_hub_event+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? lock_acquire+0x187/0x300 ? process_one_work+0x475/0xb90 ? srso_alias_return_thunk+0x5/0xfbef5 ? lock_release+0xc8/0x290 ? srso_alias_return_thunk+0x5/0xfbef5 process_one_work+0x4d7/0xb90 ? __pfx_process_one_work+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? __list_add_valid_or_report+0x37/0xf0 ? __pfx_hub_event+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 worker_thread+0x2d8/0x570 ? __pfx_worker_thread+0x10/0x10 kthread+0x1ad/0x1f0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x3c9/0x540 ? __pfx_ret_from_fork+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? __switch_to+0x2e9/0x730 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK>
Title usb: misc: usbio: fix disconnect UAF in client teardown
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-07-25T08:51:22.478Z

Reserved: 2026-07-19T15:36:31.789Z

Link: CVE-2026-64453

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.