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CVE-2026-68217

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: media: pwc: Drain fill_buf on start_streaming() failure pwc_isoc_init() submits its isochronous URBs with usb_submit_urb(.., GFP_KERNEL) in a loop. After the first URB is submitted, its completion handler pwc_isoc_handler() can run on another CPU before the loop finishes: start_streaming() pwc_isoc_init() usb_submit_urb(urbs[0], GFP_KERNEL) pwc_isoc_handler(urbs[0]) pdev->fill_buf = pwc_get_next_fill_buf(pdev) usb_submit_urb(urbs[i>0], ..) -> fails pwc_isoc_cleanup(pdev) /* kills URBs */ return ret; pwc_cleanup_queued_bufs(pdev, VB2_BUF_STATE_QUEUED) pwc_get_next_fill_buf() detaches a buffer from pdev->queued_bufs and stores it in pdev->fill_buf. The error path in start_streaming() only drains pdev->queued_bufs, so the buffer parked in pdev->fill_buf is leaked. vb2_start_streaming() then triggers WARN_ON(owned_by_drv_count). stop_streaming() already handles this since commit 80b0963e1698 ("[media] pwc: fix WARN_ON"), which added the fill_buf drain in the teardown path but not in the start_streaming() error path. Mirror that handling on failure so start_streaming() returns with no buffer owned by the driver. Issue identified by automated review of the INV-003 series at https://sashiko.dev/

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-10 13:20:09.657000
Last modified
2026-11-06 17:19:22.663000
View original CVE JSON
{
  "id": "CVE-2026-68217",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-10T13:20:09.657",
  "lastModified": "2026-11-06T17:19:22.663",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: pwc: Drain fill_buf on start_streaming() failure\n\npwc_isoc_init() submits its isochronous URBs with\nusb_submit_urb(.., GFP_KERNEL) in a loop. After the first URB is\nsubmitted, its completion handler pwc_isoc_handler() can run on another\nCPU before the loop finishes:\n\n  start_streaming()\n    pwc_isoc_init()\n      usb_submit_urb(urbs[0], GFP_KERNEL)\n                                  pwc_isoc_handler(urbs[0])\n                                    pdev->fill_buf =\n                                      pwc_get_next_fill_buf(pdev)\n      usb_submit_urb(urbs[i>0], ..)  -> fails\n      pwc_isoc_cleanup(pdev)           /* kills URBs */\n      return ret;\n    pwc_cleanup_queued_bufs(pdev, VB2_BUF_STATE_QUEUED)\n\npwc_get_next_fill_buf() detaches a buffer from pdev->queued_bufs and\nstores it in pdev->fill_buf. The error path in start_streaming() only\ndrains pdev->queued_bufs, so the buffer parked in pdev->fill_buf is\nleaked. vb2_start_streaming() then triggers\nWARN_ON(owned_by_drv_count).\n\nstop_streaming() already handles this since commit 80b0963e1698\n(\"[media] pwc: fix WARN_ON\"), which added the fill_buf drain in the\nteardown path but not in the start_streaming() error path. Mirror that\nhandling on failure so start_streaming() returns with no buffer owned\nby the driver.\n\nIssue identified by automated review of the INV-003 series at\nhttps://sashiko.dev/"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/media/usb/pwc/pwc-if.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "885fe18f5542fe283a17f70583383c6cadcba1c3",
              "lessThan": "97f3c15957ec7e6d249f05407ad947c0644df24d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "885fe18f5542fe283a17f70583383c6cadcba1c3",
              "lessThan": "a4afffd148991a826e8995362fb10cf8705c1130",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "885fe18f5542fe283a17f70583383c6cadcba1c3",
              "lessThan": "eabe9a59640698137d7382d5b549e95dc37f7565",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "885fe18f5542fe283a17f70583383c6cadcba1c3",
              "lessThan": "a56e7641e09bd80b976e944ae759109b86fd5b38",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "885fe18f5542fe283a17f70583383c6cadcba1c3",
              "lessThan": "acc789b2173070638cad89c2b61d33ed338be0dd",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "885fe18f5542fe283a17f70583383c6cadcba1c3",
              "lessThan": "9afd605dcd96c7a45f338eded1de16679b30e1df",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "885fe18f5542fe283a17f70583383c6cadcba1c3",
              "lessThan": "5d4812668b03f823b5044789d6aa77fe56b42587",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "885fe18f5542fe283a17f70583383c6cadcba1c3",
              "lessThan": "906e410dcffbbd99fb4081abab817a830033aa28",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/media/usb/pwc/pwc-if.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "3.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.265",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.216",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.183",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.148",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.101",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.42",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.6",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-11-06T16:44:48.652931Z",
          "id": "CVE-2026-68217",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/5d4812668b03f823b5044789d6aa77fe56b42587",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
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      "url": "https://git.kernel.org/stable/c/906e410dcffbbd99fb4081abab817a830033aa28",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/97f3c15957ec7e6d249f05407ad947c0644df24d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9afd605dcd96c7a45f338eded1de16679b30e1df",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a4afffd148991a826e8995362fb10cf8705c1130",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
      "url": "https://git.kernel.org/stable/c/a56e7641e09bd80b976e944ae759109b86fd5b38",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
      "url": "https://git.kernel.org/stable/c/acc789b2173070638cad89c2b61d33ed338be0dd",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/eabe9a59640698137d7382d5b549e95dc37f7565",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}