CVE-2022-48878

/// Technical description

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

Bluetooth: hci_qca: Fix driver shutdown on closed serdev

The driver shutdown callback (which sends EDL_SOC_RESET to the device

over serdev) should not be invoked when HCI device is not open (e.g. if

hci_dev_open_sync() failed), because the serdev and its TTY are not open

either. Also skip this step if device is powered off

(qca_power_shutdown()).

The shutdown callback causes use-after-free during system reboot with

Qualcomm Atheros Bluetooth:

Unable to handle kernel paging request at virtual address

0072662f67726fd7

...

CPU: 6 PID: 1 Comm: systemd-shutdow Tainted: G W

6.1.0-rt5-00325-g8a5f56bcfcca #8

Hardware name: Qualcomm Technologies, Inc. Robotics RB5 (DT)

Call trace:

tty_driver_flush_buffer+0x4/0x30

serdev_device_write_flush+0x24/0x34

qca_serdev_shutdown+0x80/0x130 [hci_uart]

device_shutdown+0x15c/0x260

kernel_restart+0x48/0xac

KASAN report:

BUG: KASAN: use-after-free i

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References