CVE-2026-23146

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_uart: fix null-ptr-deref in hci_uart_write_work hci_uart_set_proto() sets HCI_UART_PROTO_INIT before calling hci_uart_register_dev(), which calls proto->open() to initialize hu->priv. However, if a TTY write wakeup occurs during this window, hci_uart_tx_wakeup() may schedule write_work before hu->priv is initialized, leading to a NULL pointer dereference in hci_uart_write_work() when proto->dequeue() accesses hu->priv. The race condition is: CPU0 CPU1 ---- ---- hci_uart_set_proto() set_bit(HCI_UART_PROTO_INIT) hci_uart_register_dev() tty write wakeup hci_uart_tty_wakeup() hci_uart_tx_wakeup() schedule_work(&hu->write_work) proto->open(hu) // initializes hu->priv hci_uart_write_work() hci_uart_dequeue() proto->dequeue(hu) // accesses hu->priv (NULL!) Fix this by moving set_bit(HCI_UART_PROTO_INIT) after proto->open() succeeds, ensuring hu->priv is initialized before any work can be scheduled.

CVSS Score

Affected Products

Related Weaknesses (CWE)

References

• https://git.kernel.org/stable/c/03e8c90c62233382042b7bd0fa8b8900552fdb62Patch
• https://git.kernel.org/stable/c/0c3cd7a0b862c37acbee6d9502107146cc944398Patch
• https://git.kernel.org/stable/c/186d147cf7689ba1f9b3ddb753ab634a84940cc9Patch
• https://git.kernel.org/stable/c/53e54cb31e667fca05b1808b990eac0807d1dab0Patch
• https://git.kernel.org/stable/c/937a573423ce5a96fdb1fd425dc6b8d8d4ab5779Patch
• https://git.kernel.org/stable/c/b0a900939e7e4866d9b90e9112514b72c451e873Patch
• https://git.kernel.org/stable/c/ccc683f597ceb28deb966427ae948e5ac739a909Patch