CVE-2026-90305

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().

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/8a58a41100ea377e978d99600ec24a9bd0273662
https://git.kernel.org/stable/c/8de56782d6e5ba7a9f8c820342dccde65502f93f

Configurations

No configuration.

History

17 Sep 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 17:17

Updated : 2026-09-17 17:17

NVD link : CVE-2026-90305

Mitre link : CVE-2026-90305

CVE.ORG link : CVE-2026-90305

JSON object : View

Products Affected

No product.

CWE

No CWE.

{"id": "CVE-2026-90305", "cveTags": [], "metrics": {}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "c6e61c06d6061750597e79c598acb5dead44c35b", "lessThan": "8de56782d6e5ba7a9f8c820342dccde65502f93f", "versionType": "git"}, {"status": "affected", "version": "c6e61c06d6061750597e79c598acb5dead44c35b", "lessThan": "8a58a41100ea377e978d99600ec24a9bd0273662", "versionType": "git"}], "programFiles": ["arch/arm/Kconfig"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "7.1"}, {"status": "unaffected", "version": "0", "lessThan": "7.1", "versionType": "semver"}, {"status": "unaffected", "version": "7.2.6", "versionType": "semver", "lessThanOrEqual": "7.2.*"}, {"status": "unaffected", "version": "7.3-rc1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["arch/arm/Kconfig"], "defaultStatus": "affected"}]}], "published": "2026-09-17T17:17:28.163", "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"}], "vulnStatus": "Received", "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()."}], "lastModified": "2026-09-17T17:17:28.163", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}