Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_uart: clear HCI_UART_SENDING when write_work is canceled HCI_UART_SENDING bit in tx_state means write_work is pending and blocks queueing it again. Currently this bit is not cleared when canceling the work in hci_uart_close(), which blocks future writes when device is reopened later if write_work was pending. Fix by clearing HCI_UART_SENDING when canceling the work. Also make clearing of tx_skb safe by using disable_work_sync + enable_work instead of just cancel_work_sync. hci_uart_flush() purges the proto tx queue so we can cancel the pending write_work there, instead of doing it just in hci_uart_close(). Re-enable and possibly requeue the work after queue flush.
References4
Metrics
- CVSS 3.1
-
8.0
HIGH
Score source: CNA
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 9 · as of 12 November 2026
- CWE
- CWE-667
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