net/sched: act_mpls: Fix warning during failed attribute validation

{
  "id": "5633f80a14395d9e3ad467b1bbf471e2f3fb7f7763e0d7b4f53f61fe626c4c21",
  "url": "https://osv.dev/vulnerability/CVE-2023-52906",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "net/sched: act_mpls: Fix warning during failed attribute validation",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: net/sched: act_mpls: Fix warning during failed attribute validation The 'TCA_MPLS_LABEL' attribute is of 'NLA_U32' type, but has a validation type of 'NLA_VALIDATE_FUNCTION'. This is an invalid combination according to the comment above 'struct nla_policy': \" Meaning of `validate' field, use via NLA_POLICY_VALIDATE_FN: NLA_BINARY Validation function called for the attribute. All other Unused - but note that it's a union \" This can trigger the warning [1] in nla_get_range_unsigned() when validation of the attribute fails. Despite being of 'NLA_U32' type, the associated 'min'/'max' fields in the policy are negative as they are aliased by the 'validate' field. Fix by changing the attribute type to 'NLA_BINARY' which is consistent with the above comment and all other users of NLA_POLICY_VALIDATE_FN(). As a result, move the length validation to the validation function. No regressions in MPLS tests: # ./tdc.py -f tc-tests/actions/mpls.json [...] # echo $? 0 [1] WARNING: CPU: 0 PID: 17743 at lib/nlattr.c:118 nla_get_range_unsigned+0x1d8/0x1e0 lib/nlattr.c:117 Modules linked in: CPU: 0 PID: 17743 Comm: syz-executor.0 Not tainted 6.1.0-rc8 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-48-gd9c812dda519-prebuilt.qemu.org 04/01/2014 RIP: 0010:nla_get_range_unsigned+0x1d8/0x1e0 lib/nlattr.c:117 [...] Call Trace: __netlink_policy_dump_write_attr+0x23d/0x990 net/netlink/policy.c:310 netlink_polic",
    "evidence": "osv:CVE-2023-52906",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
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            "value": "5.4.229",
            "evidence": "/affected/1/ranges"
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          {
            "value": "5.10.164",
            "evidence": "/affected/1/ranges"
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          {
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          {
            "value": "6.1.7",
            "evidence": "/affected/1/ranges"
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    "severity": "unknown",
    "structured": {
      "id": "CVE-2023-52906",
      "aliases": [
        "CVE-2023-52906"
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              "type": "GIT",
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                  "fixed": "2b157c3c5d6b8ddca48d53c9e662032f65af8d61"
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                  "fixed": "453277feb41c2235cf2c0de9209eef962c401457"
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              "type": "ECOSYSTEM",
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          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
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      ],
      "modified": "2026-10-28T02:30:53.445788342Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/2b157c3c5d6b8ddca48d53c9e662032f65af8d61",
        "https://git.kernel.org/stable/c/453277feb41c2235cf2c0de9209eef962c401457",
        "https://git.kernel.org/stable/c/8a97b544b98e44f596219ebb290fd2ba2fd5d644",
        "https://git.kernel.org/stable/c/9e17f99220d111ea031b44153fdfe364b0024ff2",
        "https://git.kernel.org/stable/c/9e2c38827cdc6fdd3bb375c8607fc04d289756f9",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52906.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2023-52906",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52906.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2023-52906",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 521989,
  "published_at": "2024-08-21T06:10:47.121+00:00"
}