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CVE-2026-93121

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Fix fence cleanup in ffs_dmabuf_transfer() error paths The error paths for endpoint-disabled (ESHUTDOWN) and request-allocation failure (ENOMEM) in ffs_dmabuf_transfer() jump to err_fence_put which calls dma_fence_put() on the fence. However, at that point the fence has only been kmalloc'd — dma_fence_init() has not been called yet, so the refcount and the fence ops are uninitialized. Calling dma_fence_put() on such an object leads to undefined behavior. Use kfree() instead, since the fence is just a plain allocation at this stage, and rename the label to err_fence_free to reflect the actual cleanup action.

Severity
HIGH
CVSS score
7.0 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-17 17:18:06.803000
Last modified
2026-10-19 10:17:02.090000
View original CVE JSON
{
  "id": "CVE-2026-93121",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:18:06.803",
  "lastModified": "2026-10-19T10:17:02.090",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_fs: Fix fence cleanup in ffs_dmabuf_transfer() error paths\n\nThe error paths for endpoint-disabled (ESHUTDOWN) and request-allocation\nfailure (ENOMEM) in ffs_dmabuf_transfer() jump to err_fence_put which\ncalls dma_fence_put() on the fence. However, at that point the fence has\nonly been kmalloc'd — dma_fence_init() has not been called yet, so the\nrefcount and the fence ops are uninitialized. Calling dma_fence_put() on\nsuch an object leads to undefined behavior.\n\nUse kfree() instead, since the fence is just a plain allocation at this\nstage, and rename the label to err_fence_free to reflect the actual\ncleanup action."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/usb/gadget/function/f_fs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7b07a2a7ca02a20124b552be96c5a56910795488",
              "lessThan": "be539138d9a187af3b884525a395db10797c64f1",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "7b07a2a7ca02a20124b552be96c5a56910795488",
              "lessThan": "5fd8baacc7dc477df9cac61b45491840247a9b1e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "7b07a2a7ca02a20124b552be96c5a56910795488",
              "lessThan": "58952c83dfe6ea3294a74734d2d1018c1120779a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "7b07a2a7ca02a20124b552be96c5a56910795488",
              "lessThan": "621707dc67c9846fd876d7579ec951d92aa033f1",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/usb/gadget/function/f_fs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.9",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.9",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.52",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.0,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "HIGH",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.0,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/58952c83dfe6ea3294a74734d2d1018c1120779a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5fd8baacc7dc477df9cac61b45491840247a9b1e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/621707dc67c9846fd876d7579ec951d92aa033f1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/be539138d9a187af3b884525a395db10797c64f1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}