GHSA-54QC-M2PH-JW4R

Vulnerability from github – Published: 2024-12-28 12:30 – Updated: 2025-09-26 21:30
VLAI
Details

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

ASoC: mediatek: Check num_codecs is not zero to avoid panic during probe

Following commit 13f58267cda3 ("ASoC: soc.h: don't create dummy Component via COMP_DUMMY()"), COMP_DUMMY() became an array with zero length, and only gets populated with the dummy struct after the card is registered. Since the sound card driver's probe happens before the card registration, accessing any of the members of a dummy component during probe will result in undefined behavior.

This can be observed in the mt8188 and mt8195 machine sound drivers. By omitting a dai link subnode in the sound card's node in the Devicetree, the default uninitialized dummy codec is used, and when its dai_name pointer gets passed to strcmp() it results in a null pointer dereference and a kernel panic.

In addition to that, set_card_codec_info() in the generic helpers file, mtk-soundcard-driver.c, will populate a dai link with a dummy codec when a dai link node is present in DT but with no codec property.

The result is that at probe time, a dummy codec can either be uninitialized with num_codecs = 0, or be an initialized dummy codec, with num_codecs = 1 and dai_name = "snd-soc-dummy-dai". In order to accommodate for both situations, check that num_codecs is not zero before accessing the codecs' fields but still check for the codec's dai name against "snd-soc-dummy-dai" as needed.

While at it, also drop the check that dai_name is not null in the mt8192 driver, introduced in commit 4d4e1b6319e5 ("ASoC: mediatek: mt8192: Check existence of dai_name before dereferencing"), as it is actually redundant given the preceding num_codecs != 0 check.

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2024-56685"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-908"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-12-28T10:15:11Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nASoC: mediatek: Check num_codecs is not zero to avoid panic during probe\n\nFollowing commit 13f58267cda3 (\"ASoC: soc.h: don\u0027t create dummy\nComponent via COMP_DUMMY()\"), COMP_DUMMY() became an array with zero\nlength, and only gets populated with the dummy struct after the card is\nregistered. Since the sound card driver\u0027s probe happens before the card\nregistration, accessing any of the members of a dummy component during\nprobe will result in undefined behavior.\n\nThis can be observed in the mt8188 and mt8195 machine sound drivers. By\nomitting a dai link subnode in the sound card\u0027s node in the Devicetree,\nthe default uninitialized dummy codec is used, and when its dai_name\npointer gets passed to strcmp() it results in a null pointer dereference\nand a kernel panic.\n\nIn addition to that, set_card_codec_info() in the generic helpers file,\nmtk-soundcard-driver.c, will populate a dai link with a dummy codec when\na dai link node is present in DT but with no codec property.\n\nThe result is that at probe time, a dummy codec can either be\nuninitialized with num_codecs = 0, or be an initialized dummy codec,\nwith num_codecs = 1 and dai_name = \"snd-soc-dummy-dai\". In order to\naccommodate for both situations, check that num_codecs is not zero\nbefore accessing the codecs\u0027 fields but still check for the codec\u0027s dai\nname against \"snd-soc-dummy-dai\" as needed.\n\nWhile at it, also drop the check that dai_name is not null in the mt8192\ndriver, introduced in commit 4d4e1b6319e5 (\"ASoC: mediatek: mt8192:\nCheck existence of dai_name before dereferencing\"), as it is actually\nredundant given the preceding num_codecs != 0 check.",
  "id": "GHSA-54qc-m2ph-jw4r",
  "modified": "2025-09-26T21:30:26Z",
  "published": "2024-12-28T12:30:47Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-56685"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2f2020327cc8561d7c520d2f2d9acea84fa7b3a3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/376f4800f34a28def026ff5c5d4fc5e54e1744ff"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/550279449ff54c5aa28cfca5c567308cbfb145f0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON
How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.