Description
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 products
linux: linux kernel
References10
- git.kernel.org/stable/c/03f52a9c170431e8f10e156b9dc0dae80b3e9198 Patch
- git.kernel.org/stable/c/345c24b2bcf0923dfae1ab41497351c68214ff76 Patch
- git.kernel.org/stable/c/5d45e34bf001344e2966dabca1897561bbc9e913 Patch
- git.kernel.org/stable/c/83bd62fa9620ac98d5d694bde14c50f98c8e7189 Patch
- git.kernel.org/stable/c/bdd9503c3d222d2735b56c7a8b4422ccf3de6e5c Patch
- git.kernel.org/stable/c/e5c33cdc6f402eab8abd36ecf436b22c9d3a8aff Patch
- git.kernel.org/stable/c/3727a3541788412c393eec236ad228d72efe19c7
- git.kernel.org/stable/c/d258cdce50ff3e02392917258e81a0ce9555c327
- access.redhat.com/errata/RHSA-2026:27353
- access.redhat.com/errata/RHSA-2026:27354
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 1 · as of 14 November 2026
- CWE
- CWE-416CWE-364
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