CVE-2026-46090

Summary

In the Linux kernel, the following vulnerability has been resolved:

ALSA: aloop: Fix peer runtime UAF during format-change stop

loopback_check_format() may stop the capture side when playback starts with parameters that no longer match a running capture stream. Commit 826af7fa62e3 ("ALSA: aloop: Fix racy access at PCM trigger") moved the peer lookup under cable->lock, but the actual snd_pcm_stop() still runs after dropping that lock.

A concurrent close can clear the capture entry from cable->streams[] and detach or free its runtime while the playback trigger path still holds a stale peer substream pointer.

Keep a per-cable count of in-flight peer stops before dropping cable->lock, and make free_cable() wait for those stops before detaching the runtime. This preserves the existing behavior while making the peer runtime lifetime explicit.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux597603d615d2b19a9e451d8cfac24372856a522d < 83bd62fa9620ac98d5d694bde14c50f98c8e7189affected
LinuxLinux597603d615d2b19a9e451d8cfac24372856a522d < 345c24b2bcf0923dfae1ab41497351c68214ff76affected
LinuxLinux597603d615d2b19a9e451d8cfac24372856a522d < 03f52a9c170431e8f10e156b9dc0dae80b3e9198affected
LinuxLinux597603d615d2b19a9e451d8cfac24372856a522d < bdd9503c3d222d2735b56c7a8b4422ccf3de6e5caffected
LinuxLinux597603d615d2b19a9e451d8cfac24372856a522d < 5d45e34bf001344e2966dabca1897561bbc9e913affected
LinuxLinux597603d615d2b19a9e451d8cfac24372856a522d < e5c33cdc6f402eab8abd36ecf436b22c9d3a8affaffected
LinuxLinux2.6.37affected
LinuxLinux0 < 2.6.37unaffected
LinuxLinux5.10.259 <= 5.10.*unaffected
LinuxLinux5.15.210 <= 5.15.*unaffected
LinuxLinux6.12.88 <= 6.12.*unaffected
LinuxLinux6.18.27 <= 6.18.*unaffected
LinuxLinux7.0.4 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

ADP Enrichment

kernel: ALSA: aloop: Fix peer runtime UAF during format-change stop

Additional References

References