FKIE_CVE-2026-89839

Vulnerability from fkie_nvd - Published: 2026-09-16 11:16 - Updated: 2026-09-16 11:16
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: f2fs: use the mount idmap for the owner check in f2fs_xattr_advise_set() f2fs_xattr_advise_set() calls inode_owner_or_capable() with &nop_mnt_idmap before allowing the "system.advise" xattr to be set, instead of the idmap that the VFS passes to the ->set() handler. f2fs supports idmapped mounts, so on such a mount this checks the caller's fsuid against the unmapped on-disk owner rather than the mapped owner: the actual owner can be wrongly denied with -EPERM and an unrelated caller wrongly allowed. Pass the handler's idmap instead.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3b681229e9f8fb1dd29bc65983bf3c87779e4ca3
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4c0c610b480cfbc57528aa1acbd6be12ed2a6fb1
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a54ffce4637acb0db8e695188a6c7f99f14c3576
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ab31e3b774f5d06b4489cef6c297b48c47c9dcbd
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c3e2692c7a58e0bdb84bd658d827e89dcecea3ad
Impacted products
Vendor Product Version
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{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/f2fs/xattr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4c0c610b480cfbc57528aa1acbd6be12ed2a6fb1",
              "status": "affected",
              "version": "01beba7957a26f9b7179127e8ad56bb5a0f56138",
              "versionType": "git"
            },
            {
              "lessThan": "c3e2692c7a58e0bdb84bd658d827e89dcecea3ad",
              "status": "affected",
              "version": "01beba7957a26f9b7179127e8ad56bb5a0f56138",
              "versionType": "git"
            },
            {
              "lessThan": "3b681229e9f8fb1dd29bc65983bf3c87779e4ca3",
              "status": "affected",
              "version": "01beba7957a26f9b7179127e8ad56bb5a0f56138",
              "versionType": "git"
            },
            {
              "lessThan": "ab31e3b774f5d06b4489cef6c297b48c47c9dcbd",
              "status": "affected",
              "version": "01beba7957a26f9b7179127e8ad56bb5a0f56138",
              "versionType": "git"
            },
            {
              "lessThan": "a54ffce4637acb0db8e695188a6c7f99f14c3576",
              "status": "affected",
              "version": "01beba7957a26f9b7179127e8ad56bb5a0f56138",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/f2fs/xattr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.3"
            },
            {
              "lessThan": "6.3",
              "status": "unaffected",
              "version": "0",
              "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\nf2fs: use the mount idmap for the owner check in f2fs_xattr_advise_set()\n\nf2fs_xattr_advise_set() calls inode_owner_or_capable() with \u0026nop_mnt_idmap\nbefore allowing the \"system.advise\" xattr to be set, instead of the idmap\nthat the VFS passes to the -\u003eset() handler.\n\nf2fs supports idmapped mounts, so on such a mount this checks the caller\u0027s\nfsuid against the unmapped on-disk owner rather than the mapped owner: the\nactual owner can be wrongly denied with -EPERM and an unrelated caller\nwrongly allowed.  Pass the handler\u0027s idmap instead."
    }
  ],
  "id": "CVE-2026-89839",
  "lastModified": "2026-09-16T11:16:50.727",
  "metrics": {},
  "published": "2026-09-16T11:16:50.727",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3b681229e9f8fb1dd29bc65983bf3c87779e4ca3"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4c0c610b480cfbc57528aa1acbd6be12ed2a6fb1"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/a54ffce4637acb0db8e695188a6c7f99f14c3576"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ab31e3b774f5d06b4489cef6c297b48c47c9dcbd"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c3e2692c7a58e0bdb84bd658d827e89dcecea3ad"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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