ALSA: mtpav: shut down output timer before card teardown

Summary

In the Linux kernel, the following vulnerability has been resolved: ALSA: mtpav: shut down output timer before card teardown snd_mtpav_output_timer() rearms chip->timer while holding chip->spinlock and accesses the card-private mtpav state. snd_mtpav_free() currently takes the same lock and calls timer_delete() when the timer is active. This only removes a pending timer; it does not wait for a callback that is already running and does not prevent the callback from rearming the timer. A callback running on another CPU can therefore continue after snd_mtpav_free() releases the lock and access the card-private state while the card is being torn down. It can also rearm the timer after timer_delete() has returned. Call timer_shutdown_sync() without holding chip->spinlock. This waits for any running callback to finish and prevents further rearming before the card-private mtpav state is released.

Timeline

1. Sep 17, 2026, 4:06 PM UTCCVE published
2. Oct 21, 2026, 12:49 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 793163e134028e7136c9dd9e30f7f656de1eabba; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in de75857ce374671712e1d9528844e3c0543dcef6; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 392c985c6b03dfdf4904c0d464f18735ca3c4df8; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 1e16e82581521a2fe20eda29bdc9e75286f7c950; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in c73cb5b7c159246dd572277c668851a56e516019

• Linux Linux

  2.6.12

• KernelLinux

  From 2.6.12 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.114; From 6.13.0 · fixed in 6.18.52; From 6.19.0 · fixed in 7.2.6

References 5