CVE-2026-53242
In the Linux kernel, the following vulnerability has been resolved: ALSA: PCM: Fix wait queue list corruption in snd_pcm_drain() on linked streams snd_pcm_drain() uses init_waitqueue_entry which does not clear entry.prev/next, and add_wait_queue with a…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.13%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: PCM: Fix wait queue list corruption in snd_pcm_drain() on linked streams snd_pcm_drain() uses init_waitqueue_entry which does not clear entry.prev/next, and add_wait_queue with a conditional remove_wait_queue that is skipped when to_check is no longer in the group after concurrent UNLINK. The orphaned wait entry remains on the unlinked substream sleep queue. On the next drain iteration, add_wait_queue adds the entry to a new queue while still linked on the old one, corrupting both lists. A subsequent wake_up dereferences NULL at the func pointer (mapped from the spinlock at offset 0 of the misinterpreted wait_queue_head_t), causing a kernel panic. Replace init_waitqueue_entry/add_wait_queue/conditional remove_wait_queue with init_wait_entry/prepare_to_wait/ finish_wait. init_wait_entry clears prev/next via INIT_LIST_HEAD on each iteration and sets autoremove_wake_function which auto-removes the entry on wake-up. finish_wait safely handles both the already-removed and still-queued cases.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.13% probability · 3th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/06eca2235a3fd281dddf25b0a97772b25b5bb573
- https://git.kernel.org/stable/c/7c71a9522555ff137a9ca36b15d759ca04d84788Patch
- https://git.kernel.org/stable/c/88fe2e3658726cb21ff2dcf9770bf672f9b9d31bPatch
- https://git.kernel.org/stable/c/b053fcd8912f06c30f932f5b8ec41c72de474695Patch
- https://git.kernel.org/stable/c/cac5bf3500ee6422cf64e0df0b5daeecfed42917Patch
- https://git.kernel.org/stable/c/cd98837db15f323463b8df07282ac723bd5c3fedPatch
- https://git.kernel.org/stable/c/d68b621bb5a48051932f1017a6e1bc9b18f854d0Patch
- https://git.kernel.org/stable/c/d842f26a167e77a36f3ed333b9fa99d36ef99fe6Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.