FKIE_CVE-2026-74749

Vulnerability from fkie_nvd - Published: 2026-08-26 15:16 - Updated: 2026-08-26 15:16
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: rseq: Prevent hard lockup on granted time slice extension __exit_to_user_mode_loop() invokes rseq_grant_timeslice_extension() with interrupts enabled. If the extension is granted it invokes hrtimer_rearm_deferred_tif() to ensure that a pending deferred hrtimer rearm is handled before exiting to user space. Though this invokes __hrtimer_rearm_deferred() which expects to be invoked with interrupts disabled as it takes hrtimer_cpu_base::lock with raw_spin_lock(). That's a livelock waiting to happen and caught by lockdep: WARNING: ./include/linux/hrtimer_rearm.h:17 at irqentry_exit, CPU#1: slice_test WARNING: inconsistent lock state inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. Prevent this by disabling interrupts around the invocation of hrtimer_rearm_deferred_tif() in rseq_grant_timeslice_extension(). [ tglx: Massaged change log ]
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/8bbf4405050bc4f98be68082a20efa081ea8ad9b
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ada54c2ba652348c590d1ace6a2f4ff77cbbf809
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/linux/rseq_entry.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "8bbf4405050bc4f98be68082a20efa081ea8ad9b",
              "status": "affected",
              "version": "15dd3a9488557d3e6ebcecacab79f4e56b69ab54",
              "versionType": "git"
            },
            {
              "lessThan": "ada54c2ba652348c590d1ace6a2f4ff77cbbf809",
              "status": "affected",
              "version": "15dd3a9488557d3e6ebcecacab79f4e56b69ab54",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/linux/rseq_entry.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.1"
            },
            {
              "lessThan": "7.1",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "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\nrseq: Prevent hard lockup on granted time slice extension\n\n__exit_to_user_mode_loop() invokes rseq_grant_timeslice_extension() with\ninterrupts enabled. If the extension is granted it invokes\nhrtimer_rearm_deferred_tif() to ensure that a pending deferred hrtimer\nrearm is handled before exiting to user space.\n\nThough this invokes __hrtimer_rearm_deferred() which expects to be invoked\nwith interrupts disabled as it takes hrtimer_cpu_base::lock with\nraw_spin_lock(). That\u0027s a livelock waiting to happen and caught by lockdep:\n\n    WARNING: ./include/linux/hrtimer_rearm.h:17 at irqentry_exit, CPU#1: slice_test\n    WARNING: inconsistent lock state\n    inconsistent {IN-HARDIRQ-W} -\u003e {HARDIRQ-ON-W} usage.\n\nPrevent this by disabling interrupts around the invocation of\nhrtimer_rearm_deferred_tif() in rseq_grant_timeslice_extension().\n\n[ tglx: Massaged change log ]"
    }
  ],
  "id": "CVE-2026-74749",
  "lastModified": "2026-08-26T15:16:53.933",
  "metrics": {},
  "published": "2026-08-26T15:16:53.933",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/8bbf4405050bc4f98be68082a20efa081ea8ad9b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ada54c2ba652348c590d1ace6a2f4ff77cbbf809"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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