CVE-2026-72486mailbox: mtk-adsp: fix UAF during device teardown

Official description

In the Linux kernel, the following vulnerability has been resolved: mailbox: mtk-adsp: fix UAF during device teardown When the SOF audio driver fails to initialize (e.g. firmware boot timeout), its devres unwind frees the snd_sof_dev object that the mailbox client (mtk-adsp-ipc) reaches via chan->cl->rx_callback. The mtk-adsp-mailbox shutdown clears the mailbox command registers but leaves the IRQ line unmasked, so a late interrupt can still queue a threaded handler after mbox_free_channel() had cleared chan->cl, and mbox_chan_received_data() would then trigger UAF: BUG: KASAN: slab-use-after-free in sof_ipc3_validate_fw_version sof_ipc3_validate_fw_version sof_ipc3_do_rx_work sof_ipc3_rx_msg mt8196_dsp_handle_request mtk_adsp_ipc_recv mbox_chan_received_data mtk_adsp_mbox_isr irq_thread_fn Freed by task ...: kfree devres_release_all really_probe ... (sof-audio-of-mt8196 probe failure) The crash was observed roughly three seconds after the failed probe. disable_irq() in shutdown and enable_irq() in startup. disable_irq() also waits for any in-flight interrupts, so by the time mbox_free_channel() proceeds to clear chan->cl no rx_callback can run. In addition, request the IRQ with IRQF_NO_AUTOEN so it stays masked between probe and the first client bind — otherwise an early interrupt can crash on chan->cl == NULL in mbox_chan_received_data().

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/b6337a08a63eef8efcffe3c01d479badda6bbbdb
• https://git.kernel.org/stable/c/e519c1d8c5efb5cd8d4c5bb3fe39b1bbb812bdb9
• https://git.kernel.org/stable/c/fc6c3deb1d4c0adebf7dee0b8af4082af3f17690
• https://git.kernel.org/stable/c/7d881615fb6373f71fc628b3f00186aeca87a3d5
• https://git.kernel.org/stable/c/25d6ea6c76e1b1b7c57337b2f8f1b6fc8d5c52bc
• https://git.kernel.org/stable/c/b57d1a40bc43258372fa1f4d39305e093947a262