Vulnerability-Lookup

GHSA-VC65-JH42-GC6G

Vulnerability from github – Published: 2026-10-18 18:32 – Updated: 2026-10-21 15:41

Details

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

net: ethernet: mtk_eth_soc: allocate dummy netdev sooner

The RX rings and the shared NAPI are carried by an internal "dummy" netdev (eth->dummy_dev). mtk_probe() creates that dummy device, and adds the shared tx/rx NAPI to it, only after the MAC netdevs have been registered. That order has been there since the MT7623 support was added and leaves a window in which the netdevs are visible to the network core before the shared NAPI and the dummy device exist.

If anything brings the first netdev up during that window (e.g. netifd opening the WAN link the instant the interface is registered), the first-open path runs without them. On NETSYS v2 and later SoCs mtk_rx_alloc() -> __xdp_rxq_info_reg() then dereferences eth->dummy_dev == NULL:

WARNING: CPU: ... Missing net_device from driver

in net/core/xdp.c and mtk_open() fails with -ENODEV. On NETSYS v1 SoCs (MT7621/MT7622/MT7623/MT7629) there is no page pool, so the same open instead calls napi_enable() on a napi_struct that netif_napi_add() has not initialised yet and dereferences a NULL napi->dev.

Allocate the dummy netdev and add the shared tx/rx NAPI to it before the register_netdev() loop. Both the dummy-allocation failure and a register_netdev() failure now unwind through mtk_unreg_dev(), which unregisters the net_device notifiers and the netdevs registered so far, stopping a concurrently-opened netdev (ndo_stop) and its NAPI before the dummy carrier is freed.

A netdev that opened during the window can also have queued the frame-engine reset worker (via the tx watchdog or phylink), so the probe error path now cancels eth->pending_work before freeing the shared state, as mtk_cleanup() already does on remove.

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-98796"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-18T16:17:33Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ethernet: mtk_eth_soc: allocate dummy netdev sooner\n\nThe RX rings and the shared NAPI are carried by an internal \"dummy\" netdev\n(eth-\u003edummy_dev). mtk_probe() creates that dummy device, and adds the\nshared tx/rx NAPI to it, only after the MAC netdevs have been registered.\nThat order has been there since the MT7623 support was added and leaves a\nwindow in which the netdevs are visible to the network core before the\nshared NAPI and the dummy device exist.\n\nIf anything brings the first netdev up during that window (e.g. netifd\nopening the WAN link the instant the interface is registered), the\nfirst-open path runs without them. On NETSYS v2 and later SoCs\nmtk_rx_alloc() -\u003e __xdp_rxq_info_reg() then dereferences eth-\u003edummy_dev ==\nNULL:\n\n  WARNING: CPU: ... Missing net_device from driver\n\nin net/core/xdp.c and mtk_open() fails with -ENODEV. On NETSYS v1 SoCs\n(MT7621/MT7622/MT7623/MT7629) there is no page pool, so the same open\ninstead calls napi_enable() on a napi_struct that netif_napi_add() has not\ninitialised yet and dereferences a NULL napi-\u003edev.\n\nAllocate the dummy netdev and add the shared tx/rx NAPI to it before the\nregister_netdev() loop. Both the dummy-allocation failure and a\nregister_netdev() failure now unwind through mtk_unreg_dev(), which\nunregisters the net_device notifiers and the netdevs registered so far,\nstopping a concurrently-opened netdev (ndo_stop) and its NAPI before the\ndummy carrier is freed.\n\nA netdev that opened during the window can also have queued the\nframe-engine reset worker (via the tx watchdog or phylink), so the probe\nerror path now cancels eth-\u003epending_work before freeing the shared state,\nas mtk_cleanup() already does on remove.",
  "id": "GHSA-vc65-jh42-gc6g",
  "modified": "2026-10-21T15:41:59Z",
  "published": "2026-10-18T18:32:04Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98796"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/17eafd74de5a31e30361420a2e3ebf64186b77e5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/42001839e425b2564b7297be579073a13a8fddf6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6f0c2c4f5e7143eba75153ecc8af3a03f7b6a98b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/82be3d08de9e14d5aed72377f051adb4f09fd540"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/efc91ab1d97bd991faf50baa0ead35029f341eb9"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-98796 (GCVE-0-2026-98796)

Vulnerability from cvelistv5 – Published: 2026-10-18 15:48 – Updated: 2026-10-21 12:57

Title

net: ethernet: mtk_eth_soc: allocate dummy netdev sooner

Summary

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: mtk_eth_soc: allocate dummy netdev sooner The RX rings and the shared NAPI are carried by an internal "dummy" netdev (eth->dummy_dev). mtk_probe() creates that dummy device, and adds the shared tx/rx NAPI to it, only after the MAC netdevs have been registered. That order has been there since the MT7623 support was added and leaves a window in which the netdevs are visible to the network core before the shared NAPI and the dummy device exist. If anything brings the first netdev up during that window (e.g. netifd opening the WAN link the instant the interface is registered), the first-open path runs without them. On NETSYS v2 and later SoCs mtk_rx_alloc() -> __xdp_rxq_info_reg() then dereferences eth->dummy_dev == NULL: WARNING: CPU: ... Missing net_device from driver in net/core/xdp.c and mtk_open() fails with -ENODEV. On NETSYS v1 SoCs (MT7621/MT7622/MT7623/MT7629) there is no page pool, so the same open instead calls napi_enable() on a napi_struct that netif_napi_add() has not initialised yet and dereferences a NULL napi->dev. Allocate the dummy netdev and add the shared tx/rx NAPI to it before the register_netdev() loop. Both the dummy-allocation failure and a register_netdev() failure now unwind through mtk_unreg_dev(), which unregisters the net_device notifiers and the netdevs registered so far, stopping a concurrently-opened netdev (ndo_stop) and its NAPI before the dummy carrier is freed. A netdev that opened during the window can also have queued the frame-engine reset worker (via the tx watchdog or phylink), so the probe error path now cancels eth->pending_work before freeing the shared state, as mtk_cleanup() already does on remove.

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6847 records in the last 180 days details

References

5 references

URL	Tags
https://git.kernel.org/stable/c/efc91ab1d97bd991f…
https://git.kernel.org/stable/c/42001839e425b2564…
https://git.kernel.org/stable/c/82be3d08de9e14d5a…
https://git.kernel.org/stable/c/17eafd74de5a31e30…
https://git.kernel.org/stable/c/6f0c2c4f5e7143eba…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 656e705243fd0c2864b89634ea16ed444ef64dc6 , < efc91ab1d97bd991faf50baa0ead35029f341eb9 (git) Affected: 656e705243fd0c2864b89634ea16ed444ef64dc6 , < 42001839e425b2564b7297be579073a13a8fddf6 (git) Affected: 656e705243fd0c2864b89634ea16ed444ef64dc6 , < 82be3d08de9e14d5aed72377f051adb4f09fd540 (git) Affected: 656e705243fd0c2864b89634ea16ed444ef64dc6 , < 17eafd74de5a31e30361420a2e3ebf64186b77e5 (git) Affected: 656e705243fd0c2864b89634ea16ed444ef64dc6 , < 6f0c2c4f5e7143eba75153ecc8af3a03f7b6a98b (git)
Linux	Linux	Affected: 4.6 Unaffected: 0 , < 4.6 (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.113 , ≤ 6.12.* (semver) Unaffected: 6.18.56 , ≤ 6.18.* (semver) Unaffected: 7.2.10 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/ethernet/mediatek/mtk_eth_soc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "efc91ab1d97bd991faf50baa0ead35029f341eb9",
              "status": "affected",
              "version": "656e705243fd0c2864b89634ea16ed444ef64dc6",
              "versionType": "git"
            },
            {
              "lessThan": "42001839e425b2564b7297be579073a13a8fddf6",
              "status": "affected",
              "version": "656e705243fd0c2864b89634ea16ed444ef64dc6",
              "versionType": "git"
            },
            {
              "lessThan": "82be3d08de9e14d5aed72377f051adb4f09fd540",
              "status": "affected",
              "version": "656e705243fd0c2864b89634ea16ed444ef64dc6",
              "versionType": "git"
            },
            {
              "lessThan": "17eafd74de5a31e30361420a2e3ebf64186b77e5",
              "status": "affected",
              "version": "656e705243fd0c2864b89634ea16ed444ef64dc6",
              "versionType": "git"
            },
            {
              "lessThan": "6f0c2c4f5e7143eba75153ecc8af3a03f7b6a98b",
              "status": "affected",
              "version": "656e705243fd0c2864b89634ea16ed444ef64dc6",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/net/ethernet/mediatek/mtk_eth_soc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.6"
            },
            {
              "lessThan": "4.6",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.56",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.160",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.113",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.56",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.10",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ethernet: mtk_eth_soc: allocate dummy netdev sooner\n\nThe RX rings and the shared NAPI are carried by an internal \"dummy\" netdev\n(eth-\u003edummy_dev). mtk_probe() creates that dummy device, and adds the\nshared tx/rx NAPI to it, only after the MAC netdevs have been registered.\nThat order has been there since the MT7623 support was added and leaves a\nwindow in which the netdevs are visible to the network core before the\nshared NAPI and the dummy device exist.\n\nIf anything brings the first netdev up during that window (e.g. netifd\nopening the WAN link the instant the interface is registered), the\nfirst-open path runs without them. On NETSYS v2 and later SoCs\nmtk_rx_alloc() -\u003e __xdp_rxq_info_reg() then dereferences eth-\u003edummy_dev ==\nNULL:\n\n  WARNING: CPU: ... Missing net_device from driver\n\nin net/core/xdp.c and mtk_open() fails with -ENODEV. On NETSYS v1 SoCs\n(MT7621/MT7622/MT7623/MT7629) there is no page pool, so the same open\ninstead calls napi_enable() on a napi_struct that netif_napi_add() has not\ninitialised yet and dereferences a NULL napi-\u003edev.\n\nAllocate the dummy netdev and add the shared tx/rx NAPI to it before the\nregister_netdev() loop. Both the dummy-allocation failure and a\nregister_netdev() failure now unwind through mtk_unreg_dev(), which\nunregisters the net_device notifiers and the netdevs registered so far,\nstopping a concurrently-opened netdev (ndo_stop) and its NAPI before the\ndummy carrier is freed.\n\nA netdev that opened during the window can also have queued the\nframe-engine reset worker (via the tx watchdog or phylink), so the probe\nerror path now cancels eth-\u003epending_work before freeing the shared state,\nas mtk_cleanup() already does on remove."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-21T12:57:04.919Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/efc91ab1d97bd991faf50baa0ead35029f341eb9"
        },
        {
          "url": "https://git.kernel.org/stable/c/42001839e425b2564b7297be579073a13a8fddf6"
        },
        {
          "url": "https://git.kernel.org/stable/c/82be3d08de9e14d5aed72377f051adb4f09fd540"
        },
        {
          "url": "https://git.kernel.org/stable/c/17eafd74de5a31e30361420a2e3ebf64186b77e5"
        },
        {
          "url": "https://git.kernel.org/stable/c/6f0c2c4f5e7143eba75153ecc8af3a03f7b6a98b"
        }
      ],
      "title": "net: ethernet: mtk_eth_soc: allocate dummy netdev sooner",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-98796",
    "datePublished": "2026-10-18T15:48:40.684Z",
    "dateReserved": "2026-09-25T10:25:14.370Z",
    "dateUpdated": "2026-10-21T12:57:04.919Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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

Order JSON

Publication & reservation Sightings KEV catalogs Other timestamps

Loading timeline…

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.

Action not permitted