CVE-2026-99112

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_flower: validate mask pointer after nla_next() fl_set_enc_opt() iterates the key's nested tunnel-option attributes with nla_for_each_attr() while advancing a single mask pointer via nla_next() at the bottom of each loop, so the mask cursor is driven by the number of key attributes rather than by the mask's own attributes. The nla_ok() added by commit c96adff956191 ("cls_flower: call nla_ok() before nla_next()") only validates the mask pointer that was just consumed; the pointer produced by nla_next() is used by the next iteration (fl_set_geneve_opt() and siblings) without any validation. The mask's nested attributes are validated with NL_VALIDATE_LIBERAL, which merely warns on trailing bytes that do not form a complete attribute. A mask carrying one valid attribute plus 1-3 residue bytes (or a non-aligned attribute length making msk_depth negative) therefore reaches the next iteration with msk_depth != 0, so neither the !msk_depth check in fl_set_enc_opt() nor the !depth check in the per-type helpers fires. nla_type() then reads past the mask payload and nla_parse_nested_deprecated() iterates with an nla_len taken from those bytes, reading well beyond the mask attribute (KASAN: slab-out-of-bounds read in __nla_validate_parse from fl_change()). Validate the advanced mask pointer as well: when the mask is not legitimately exhausted (msk_depth != 0) and the new pointer fails nla_ok(), reject the filter with -EINVAL. An exactly exhausted mask still skips the check, preserving exact-match behaviour for the remaining key attributes.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-10-28 11:17:30.640000

Last modified

2026-10-30 13:21:45.650000

View original CVE JSON

{
  "id": "CVE-2026-99112",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-28T11:17:30.640",
  "lastModified": "2026-10-30T13:21:45.650",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_flower: validate mask pointer after nla_next()\n\nfl_set_enc_opt() iterates the key's nested tunnel-option attributes\nwith nla_for_each_attr() while advancing a single mask pointer via\nnla_next() at the bottom of each loop, so the mask cursor is driven\nby the number of key attributes rather than by the mask's own\nattributes.  The nla_ok() added by commit c96adff956191 (\"cls_flower:\ncall nla_ok() before nla_next()\") only validates the mask pointer\nthat was just consumed; the pointer produced by nla_next() is used by\nthe next iteration (fl_set_geneve_opt() and siblings) without any\nvalidation.\n\nThe mask's nested attributes are validated with NL_VALIDATE_LIBERAL,\nwhich merely warns on trailing bytes that do not form a complete\nattribute.  A mask carrying one valid attribute plus 1-3 residue\nbytes (or a non-aligned attribute length making msk_depth negative)\ntherefore reaches the next iteration with msk_depth != 0, so neither\nthe !msk_depth check in fl_set_enc_opt() nor the !depth check in the\nper-type helpers fires.  nla_type() then reads past the mask payload\nand nla_parse_nested_deprecated() iterates with an nla_len taken\nfrom those bytes, reading well beyond the mask attribute (KASAN:\nslab-out-of-bounds read in __nla_validate_parse from fl_change()).\n\nValidate the advanced mask pointer as well: when the mask is not\nlegitimately exhausted (msk_depth != 0) and the new pointer fails\nnla_ok(), reject the filter with -EINVAL.  An exactly exhausted mask\nstill skips the check, preserving exact-match behaviour for the\nremaining key attributes."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/sched/cls_flower.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "238b5ebdb6a6e4bc90810b9f8ec0063b3dfda41a",
              "lessThan": "a9283d006eef7e3b56f0f279a49bb63f6e5e61df",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c96adff95619178e2118925578343ad54857c80c",
              "lessThan": "497944d534ffb1be300365523030c7c6517cbbb6",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c96adff95619178e2118925578343ad54857c80c",
              "lessThan": "a55d84907337580d91c0d54779d9d4b934633158",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c96adff95619178e2118925578343ad54857c80c",
              "lessThan": "cff9bf34afde46c238189cc6f7690b7e35225df1",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c96adff95619178e2118925578343ad54857c80c",
              "lessThan": "35354bf67aa0f7bace66ffb614906124ed50d59d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c96adff95619178e2118925578343ad54857c80c",
              "lessThan": "45e60747a9db2307929260d9aa9c1c6cbb70ee77",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c96adff95619178e2118925578343ad54857c80c",
              "lessThan": "bb187146c7e5c666874784e4f3fc1bc5126e6e92",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c96adff95619178e2118925578343ad54857c80c",
              "lessThan": "fee10655709c5c597e8e9f722f3035d9ea31ff3a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5.10.11",
              "lessThan": "5.10.273",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/sched/cls_flower.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.11",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.11",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.273",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.224",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.161",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.115",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.59",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.13",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/35354bf67aa0f7bace66ffb614906124ed50d59d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/45e60747a9db2307929260d9aa9c1c6cbb70ee77",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/497944d534ffb1be300365523030c7c6517cbbb6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a55d84907337580d91c0d54779d9d4b934633158",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a9283d006eef7e3b56f0f279a49bb63f6e5e61df",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/bb187146c7e5c666874784e4f3fc1bc5126e6e92",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cff9bf34afde46c238189cc6f7690b7e35225df1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fee10655709c5c597e8e9f722f3035d9ea31ff3a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}