CVE-2026-90305

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: ARM: 9483/1: select HAVE_POSIX_CPU_TIMERS_TASK_WORK Commit c6e61c06d606 ("ARM: 9463/1: Allow to enable RT") enabled PREEMPT_RT on ARM but did not select HAVE_POSIX_CPU_TIMERS_TASK_WORK. This leaves CONFIG_POSIX_CPU_TIMERS_TASK_WORK disabled, so CPU timers expire in hard IRQ context. On PREEMPT_RT this makes run_posix_cpu_timers() take the sleeping sighand->siglock: BUG: sleeping function called from invalid context at spinlock_rt.c:48 rt_spin_lock from lock_task_sighand lock_task_sighand from run_posix_cpu_timers run_posix_cpu_timers from update_process_times ARM handles TIF_NOTIFY_RESUME on all return-to-user paths, including v7-M. ARM32 KVM host support was removed by commit 541ad0150ca4 ("arm: Remove 32bit KVM host support"), so the select need not be conditional on KVM. Select it to defer POSIX CPU timer expiry to task context. Reproduced with setrlimit(RLIMIT_CPU, ...) and a busy loop. The same path is used by setitimer(ITIMER_PROF or ITIMER_VIRTUAL) and POSIX CPU timers created with timer_create().

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

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

Published

2026-09-17 17:17:28.163000

Last modified

2026-10-19 09:19:24.513000

View original CVE JSON

{
  "id": "CVE-2026-90305",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:17:28.163",
  "lastModified": "2026-10-19T09:19:24.513",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nARM: 9483/1: select HAVE_POSIX_CPU_TIMERS_TASK_WORK\n\nCommit c6e61c06d606 (\"ARM: 9463/1: Allow to enable RT\") enabled PREEMPT_RT\non ARM but did not select HAVE_POSIX_CPU_TIMERS_TASK_WORK. This leaves\nCONFIG_POSIX_CPU_TIMERS_TASK_WORK disabled, so CPU timers expire in hard\nIRQ context.\n\nOn PREEMPT_RT this makes run_posix_cpu_timers() take the sleeping\nsighand->siglock:\n\n  BUG: sleeping function called from invalid context at spinlock_rt.c:48\n    rt_spin_lock from lock_task_sighand\n    lock_task_sighand from run_posix_cpu_timers\n    run_posix_cpu_timers from update_process_times\n\nARM handles TIF_NOTIFY_RESUME on all return-to-user paths, including v7-M.\nARM32 KVM host support was removed by commit 541ad0150ca4 (\"arm: Remove\n32bit KVM host support\"), so the select need not be conditional on KVM.\n\nSelect it to defer POSIX CPU timer expiry to task context.\n\nReproduced with setrlimit(RLIMIT_CPU, ...) and a busy loop. The same path\nis used by setitimer(ITIMER_PROF or ITIMER_VIRTUAL) and POSIX CPU timers\ncreated with timer_create()."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "arch/arm/Kconfig"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "c6e61c06d6061750597e79c598acb5dead44c35b",
              "lessThan": "8de56782d6e5ba7a9f8c820342dccde65502f93f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c6e61c06d6061750597e79c598acb5dead44c35b",
              "lessThan": "8a58a41100ea377e978d99600ec24a9bd0273662",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "arch/arm/Kconfig"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "7.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "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/8a58a41100ea377e978d99600ec24a9bd0273662",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8de56782d6e5ba7a9f8c820342dccde65502f93f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}