CVE-2026-74535Bluetooth: ISO: avoid deadlocks in iso_sock_timeout

Official description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: avoid deadlocks in iso_sock_timeout iso_sock_timeout() takes lock_sock, so sync disabling the timer while holding that lock may deadlock. iso_sock_timeout() may also run concurrently with iso_conn_del(), which leads to UAF [Task 1] [Task hdev->workqueue] iso_sock_timeout iso_conn_del iso_conn_hold_unless_zero iso_chan_del `------------> iso_conn_put caller frees hcon iso_conn_put iso_conn_free conn->hcon->iso_data = NULL; /* UAF */ Fix the deadlock by removing the disable from the lock_sock sections. Move the timer from iso_conn to iso_pinfo to decouple it from iso_conn which may need to be freed in lock_sock section. Convert some of the clear_timer to disable_timer.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/16d89a63e08280abeef7218970a3bbd7ca62b021
• https://git.kernel.org/stable/c/82e982f54f962f72646868ddbb2c3bd9ea178568
• https://git.kernel.org/stable/c/3c3d5f85db80145636bb991a6005e2760012b985
• https://git.kernel.org/stable/c/200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43