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FKIE_CVE-2026-89983

Vulnerability from fkie_nvd - Published: 2026-09-16 11:17 - Updated: 2026-09-16 11:17
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: i2c: core: fix debugfs UAF on adapter removal i2c_del_adapter() frees the adapter's debugfs directory before it unregisters the adapter device, but the new_device sysfs attribute stays writable until device_del(). A write racing with removal still reaches i2c_device_probe(), which passes the freed adap->debugfs to debugfs_create_dir() as the new client's parent: BUG: KASAN: slab-use-after-free in lookup_noperm_common+0x407/0x430 Read of size 4 at addr ffff88803ef87810 by task syz.0.61/6090 lookup_noperm_common+0x407/0x430 simple_start_creating+0x9c/0x110 debugfs_start_creating+0xdb/0x1a0 debugfs_create_dir+0x24/0x350 i2c_device_probe+0x814/0xbf0 It's technically possible to create a client after i2c_deregister_clients has run. That client will never be unregistered and make wait_for_completion hang. Close the window by removing the new_device attribute at the start of i2c_del_adapter(). device_remove_file() will drain any clients left.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/112b3d48084c820bbccf41d9783fd122e3ac4cb0
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1f1bcd4eca6caa3e4258d9a31925112539406eb6
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/552836be2d95c688eede6371f85532abe1a71232
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/643fb872aa04342d27dbef52b2b3cf3fe71b2c7b
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/b15b548d52b43ba8ac4652bc2c7244a8dd1e9622
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/dc33a9762538b3250ed6b5644a4d44c748be33a6
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f9094ace03e0a532cc6505d2e97b61ae738da4ed
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/i2c/i2c-core-base.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "dc33a9762538b3250ed6b5644a4d44c748be33a6",
              "status": "affected",
              "version": "0e8926abfd7aee220e44be5566affd7a8580b50e",
              "versionType": "git"
            },
            {
              "lessThan": "1f1bcd4eca6caa3e4258d9a31925112539406eb6",
              "status": "affected",
              "version": "e2a268b0f512fb18ae5961b1fdfaf610ed6bd661",
              "versionType": "git"
            },
            {
              "lessThan": "f9094ace03e0a532cc6505d2e97b61ae738da4ed",
              "status": "affected",
              "version": "4a2be5a72865bdd219b2d8c327b9fa03e87a4a9e",
              "versionType": "git"
            },
            {
              "lessThan": "643fb872aa04342d27dbef52b2b3cf3fe71b2c7b",
              "status": "affected",
              "version": "73febd775bdbdb98c81255ff85773ac410ded5c4",
              "versionType": "git"
            },
            {
              "lessThan": "112b3d48084c820bbccf41d9783fd122e3ac4cb0",
              "status": "affected",
              "version": "73febd775bdbdb98c81255ff85773ac410ded5c4",
              "versionType": "git"
            },
            {
              "lessThan": "552836be2d95c688eede6371f85532abe1a71232",
              "status": "affected",
              "version": "73febd775bdbdb98c81255ff85773ac410ded5c4",
              "versionType": "git"
            },
            {
              "lessThan": "b15b548d52b43ba8ac4652bc2c7244a8dd1e9622",
              "status": "affected",
              "version": "73febd775bdbdb98c81255ff85773ac410ded5c4",
              "versionType": "git"
            },
            {
              "lessThan": "5.15.221",
              "status": "affected",
              "version": "5.15.168",
              "versionType": "semver"
            },
            {
              "lessThan": "6.1.188",
              "status": "affected",
              "version": "6.1.113",
              "versionType": "semver"
            },
            {
              "lessThan": "6.6.157",
              "status": "affected",
              "version": "6.6.55",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/i2c/i2c-core-base.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.8"
            },
            {
              "lessThan": "6.8",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.221",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.188",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.110",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.51",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ni2c: core: fix debugfs UAF on adapter removal\n\ni2c_del_adapter() frees the adapter\u0027s debugfs directory before it\nunregisters the adapter device, but the new_device sysfs attribute\nstays writable until device_del(). A write racing with removal still\nreaches i2c_device_probe(), which passes the freed adap-\u003edebugfs to\ndebugfs_create_dir() as the new client\u0027s parent:\n\n  BUG: KASAN: slab-use-after-free in lookup_noperm_common+0x407/0x430\n  Read of size 4 at addr ffff88803ef87810 by task syz.0.61/6090\n   lookup_noperm_common+0x407/0x430\n   simple_start_creating+0x9c/0x110\n   debugfs_start_creating+0xdb/0x1a0\n   debugfs_create_dir+0x24/0x350\n   i2c_device_probe+0x814/0xbf0\n\nIt\u0027s technically possible to create a client after i2c_deregister_clients\nhas run. That client will never be unregistered and make\nwait_for_completion hang.\n\nClose the window by removing the new_device attribute at the start of\ni2c_del_adapter(). device_remove_file() will drain any clients left."
    }
  ],
  "id": "CVE-2026-89983",
  "lastModified": "2026-09-16T11:17:09.270",
  "metrics": {},
  "published": "2026-09-16T11:17:09.270",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/112b3d48084c820bbccf41d9783fd122e3ac4cb0"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1f1bcd4eca6caa3e4258d9a31925112539406eb6"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/552836be2d95c688eede6371f85532abe1a71232"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/643fb872aa04342d27dbef52b2b3cf3fe71b2c7b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b15b548d52b43ba8ac4652bc2c7244a8dd1e9622"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/dc33a9762538b3250ed6b5644a4d44c748be33a6"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/f9094ace03e0a532cc6505d2e97b61ae738da4ed"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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