clocksource/drivers/timer-sp804: Fix an Oops when read_current_timer is called on ARM32 platforms where the SP804 is not registered as the sched_clock.

{
  "id": "be6e759c796f948540263692a16365f1f529da68549fb05ce1967772d349975e",
  "url": "https://osv.dev/vulnerability/CVE-2026-46257",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "clocksource/drivers/timer-sp804: Fix an Oops when read_current_timer is called on ARM32 platforms where the SP804 is not registered as the sched_clock.",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: clocksource/drivers/timer-sp804: Fix an Oops when read_current_timer is called on ARM32 platforms where the SP804 is not registered as the sched_clock. On SP804, the delay timer shares the same clkevt instance with sched_clock. On some platforms, when sp804_clocksource_and_sched_clock_init is called with use_sched_clock not set to 1, sched_clkevt is not properly initialized. However, sp804_register_delay_timer is invoked unconditionally, and read_current_timer() subsequently calls sp804_read on an uninitialized sched_clkevt, leading to a kernel Oops when accessing sched_clkevt->value. Declare a dedicated clkevt instance exclusively for delay timer, instead of sharing the same clkevt with sched_clock. This ensures that read_current_timer continues to work correctly regardless of whether SP804 is selected as the sched_clock.",
    "evidence": "osv:CVE-2026-46257",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.19.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-46257",
      "aliases": [
        "CVE-2026-46257"
      ],
      "affected": [
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                  "fixed": "694921a93f3e3621e067afc545cedf6fe3b234a9"
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          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-46257.json"
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        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
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                  "introduced": "6.19.0"
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                  "fixed": "6.19.4"
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          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-46257.json"
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      ],
      "modified": "2026-10-28T02:30:32.454021188Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/693b0b594b0f278bafa784984129c0c0f988e352",
        "https://git.kernel.org/stable/c/694921a93f3e3621e067afc545cedf6fe3b234a9",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46257.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-46257",
        "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/2026/46xxx/CVE-2026-46257.json"
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    "related_cves": [
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        "value": "CVE-2026-46257",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 499330,
  "published_at": "2026-06-03T15:49:54.286+00:00"
}