---
id: CVE-2026-46049
title: 'ALSA: ctxfi: Add fallback to default RSR for S/PDIF'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ALSA: ctxfi: Add fallback to default RSR for S/PDIF

  spdif_passthru_playback_get_resources() uses atc->pll_rate as the RSR
  for the MSR calculation loop. However, pll_ra…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 8cc72361481f00253f1e468ade5795427386d593 <
    d0b53842211f73a10ea174100a213f7fa14b9f33
  - >-
    Linux >= 8cc72361481f00253f1e468ade5795427386d593 <
    615b7a5e5d8be68d52f262579906f7e015ba4606
  - >-
    Linux >= 8cc72361481f00253f1e468ade5795427386d593 <
    dfc00979ff00d9dfdfa1df32144a272ee2728102
  - >-
    Linux >= 8cc72361481f00253f1e468ade5795427386d593 <
    25ded535ee261161bcf19dafd525c542e606559d
  - >-
    Linux >= 8cc72361481f00253f1e468ade5795427386d593 <
    30f9494c6f2b53a78822cfb653ffbb1d092d44c8
  - >-
    Linux >= 8cc72361481f00253f1e468ade5795427386d593 <
    09496158f6ebba8830593f8972035c02f97124c1
  - >-
    Linux >= 8cc72361481f00253f1e468ade5795427386d593 <
    95b1ee8442cabbde83b2848e7c6100df90f3a00d
  - >-
    Linux >= 8cc72361481f00253f1e468ade5795427386d593 <
    7d61662197ecdc458e33e475b6ada7f6da61d364
  - Linux 2.6.31
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T16:06:26.866490Z'
published: '2026-05-27'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T16:13:34.308Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-46049'
references:
  - url: 'https://git.kernel.org/stable/c/d0b53842211f73a10ea174100a213f7fa14b9f33'
  - url: 'https://git.kernel.org/stable/c/615b7a5e5d8be68d52f262579906f7e015ba4606'
  - url: 'https://git.kernel.org/stable/c/dfc00979ff00d9dfdfa1df32144a272ee2728102'
  - url: 'https://git.kernel.org/stable/c/25ded535ee261161bcf19dafd525c542e606559d'
  - url: 'https://git.kernel.org/stable/c/30f9494c6f2b53a78822cfb653ffbb1d092d44c8'
  - url: 'https://git.kernel.org/stable/c/09496158f6ebba8830593f8972035c02f97124c1'
  - url: 'https://git.kernel.org/stable/c/95b1ee8442cabbde83b2848e7c6100df90f3a00d'
  - url: 'https://git.kernel.org/stable/c/7d61662197ecdc458e33e475b6ada7f6da61d364'
tags:
  - cve.org
epss: 0.00123
epssPercentile: 0.02028
ingestedAt: '2026-11-06T16:57:43.346Z'
---

## Overview

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

ALSA: ctxfi: Add fallback to default RSR for S/PDIF

spdif_passthru_playback_get_resources() uses atc->pll_rate as the RSR
for the MSR calculation loop. However, pll_rate is only updated in
atc_pll_init() and not in hw_pll_init(), so it remains 0 after the
card init.

When spdif_passthru_playback_setup() skips atc_pll_init() for
32000 Hz, (rsr * desc.msr) always becomes 0, causing the loop to spin
indefinitely.

Add fallback to use atc->rsr when atc->pll_rate is 0. This reflects
the hardware state, since hw_card_init() already configures the PLL
to the default RSR.

## Affected

- `Linux >= 8cc72361481f00253f1e468ade5795427386d593 < d0b53842211f73a10ea174100a213f7fa14b9f33`
- `Linux >= 8cc72361481f00253f1e468ade5795427386d593 < 615b7a5e5d8be68d52f262579906f7e015ba4606`
- `Linux >= 8cc72361481f00253f1e468ade5795427386d593 < dfc00979ff00d9dfdfa1df32144a272ee2728102`
- `Linux >= 8cc72361481f00253f1e468ade5795427386d593 < 25ded535ee261161bcf19dafd525c542e606559d`
- `Linux >= 8cc72361481f00253f1e468ade5795427386d593 < 30f9494c6f2b53a78822cfb653ffbb1d092d44c8`
- `Linux >= 8cc72361481f00253f1e468ade5795427386d593 < 09496158f6ebba8830593f8972035c02f97124c1`
- `Linux >= 8cc72361481f00253f1e468ade5795427386d593 < 95b1ee8442cabbde83b2848e7c6100df90f3a00d`
- `Linux >= 8cc72361481f00253f1e468ade5795427386d593 < 7d61662197ecdc458e33e475b6ada7f6da61d364`
- `Linux 2.6.31`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.