You are viewing this page in an unauthorized frame window.
This is a potential security issue, you are being redirected to
https://nvd.nist.gov
An official website of the United States government
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.
In the Linux kernel, the following vulnerability has been resolved:
x86/efi: Fix graceful fault handling after FPU softirq changes
Since commit d02198550423 ("x86/fpu: Improve crypto performance by
making kernel-mode FPU reliably usable in softirqs"), kernel_fpu_begin()
calls fpregs_lock() which uses local_bh_disable() instead of the
previous preempt_disable(). This sets SOFTIRQ_OFFSET in preempt_count
during the entire EFI runtime service call, causing in_interrupt() to
return true in normal task context.
The graceful page fault handler efi_crash_gracefully_on_page_fault()
uses in_interrupt() to bail out for faults in real interrupt context.
With SOFTIRQ_OFFSET now set, the handler always bails out, leaving EFI
firmware page faults unhandled. This escalates to die() which also sees
in_interrupt() as true and calls panic("Fatal exception in interrupt"),
resulting in a hard system freeze. On systems with buggy firmware that
triggers page faults during EFI runtime calls (e.g., accessing unmapped
memory in GetTime()), this causes an unrecoverable hang instead of the
expected graceful EFI_ABORTED recovery.
Fix by replacing in_interrupt() with !in_task(). This preserves the
original intent of bailing for interrupts or NMI faults, while no longer
falsely triggering from the FPU code path's local_bh_disable().
[ardb: Sashiko spotted that using 'in_hardirq() || in_nmi()' leaves a
window where a softirq may be taken before fpregs_lock() is
called, but after efi_rts_work.efi_rts_id has been assigned,
and any page faults occurring in that window will then be
misidentified as having been caused by the firmware. Instead,
use !in_task(), which incorporates in_serving_softirq(). ]
Metrics
NVD enrichment efforts reference publicly available information to associate
vector strings. CVSS information contributed by other sources is also
displayed.
By selecting these links, you will be leaving NIST webspace.
We have provided these links to other web sites because they
may have information that would be of interest to you. No
inferences should be drawn on account of other sites being
referenced, or not, from this page. There may be other web
sites that are more appropriate for your purpose. NIST does
not necessarily endorse the views expressed, or concur with
the facts presented on these sites. Further, NIST does not
endorse any commercial products that may be mentioned on
these sites. Please address comments about this page to [email protected].
Title: Linux, Description: En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:
x86/efi: Corrección del manejo elegante de fallos después de los cambios en softirq de FPU
Desde el commit d02198550423 ('x86/fpu: Mejorar el rendimiento criptográfico haciendo que la FPU en modo kernel sea utilizable de forma fiable en softirqs'), kernel_fpu_begin() llama a fpregs_lock() que usa local_bh_disable() en lugar del preempt_disable() anterior. Esto establece SOFTIRQ_OFFSET en preempt_count durante toda la llamada al servicio de tiempo de ejecución de EFI, haciendo que in_interrupt() devuelva verdadero en un contexto de tarea normal.
El gestor elegante de fallos de página efi_crash_gracefully_on_page_fault() usa in_interrupt() para salir de los fallos en un contexto de interrupción real. Con SOFTIRQ_OFFSET ahora establecido, el gestor siempre sale, dejando los fallos de página del firmware EFI sin manejar. Esto escala a die() que también ve in_interrupt() como verdadero y llama a panic('Excepción fatal en interrupción'), resultando en una congelación dura del sistema. En sistemas con firmware defectuoso que dispara fallos de página durante las llamadas de tiempo de ejecución de EFI (p. ej., acceder a memoria no mapeada en GetTime()), esto causa un cuelgue irrecuperable en lugar de la recuperación elegante EFI_ABORTED esperada.
Solución reemplazando in_interrupt() con !in_task(). Esto preserva la intención original de salir por interrupciones o fallos NMI, mientras ya no se dispara falsamente desde el local_bh_disable() de la ruta de código de la FPU.
[ardb: Sashiko detectó que usar 'in_hardirq() || in_nmi()' deja una ventana donde un softirq puede ser tomado antes de que se llame a fpregs_lock(), pero después de que efi_rts_work.efi_rts_id haya sido asignado, y cualquier fallo de página que ocurra en esa ventana será entonces mal identificado como causado por el firmware. En su lugar, use !in_task(), que incorpora in_serving_softirq(). ]
Initial Analysis by NIST7/08/2026 3:04:41 PM
Action
Type
Old Value
New Value
Added
CVSS V3.1
AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Added
CWE
NVD-CWE-noinfo
Added
CPE Configuration
OR
*cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*
*cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*
*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.7
*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.15 up to (excluding) 6.18.30
New CVE Received from kernel.org6/08/2026 1:16:47 PM
Action
Type
Old Value
New Value
Added
Description
In the Linux kernel, the following vulnerability has been resolved:
x86/efi: Fix graceful fault handling after FPU softirq changes
Since commit d02198550423 ("x86/fpu: Improve crypto performance by
making kernel-mode FPU reliably usable in softirqs"), kernel_fpu_begin()
calls fpregs_lock() which uses local_bh_disable() instead of the
previous preempt_disable(). This sets SOFTIRQ_OFFSET in preempt_count
during the entire EFI runtime service call, causing in_interrupt() to
return true in normal task context.
The graceful page fault handler efi_crash_gracefully_on_page_fault()
uses in_interrupt() to bail out for faults in real interrupt context.
With SOFTIRQ_OFFSET now set, the handler always bails out, leaving EFI
firmware page faults unhandled. This escalates to die() which also sees
in_interrupt() as true and calls panic("Fatal exception in interrupt"),
resulting in a hard system freeze. On systems with buggy firmware that
triggers page faults during EFI runtime calls (e.g., accessing unmapped
memory in GetTime()), this causes an unrecoverable hang instead of the
expected graceful EFI_ABORTED recovery.
Fix by replacing in_interrupt() with !in_task(). This preserves the
original intent of bailing for interrupts or NMI faults, while no longer
falsely triggering from the FPU code path's local_bh_disable().
[ardb: Sashiko spotted that using 'in_hardirq() || in_nmi()' leaves a
window where a softirq may be taken before fpregs_lock() is
called, but after efi_rts_work.efi_rts_id has been assigned,
and any page faults occurring in that window will then be
misidentified as having been caused by the firmware. Instead,
use !in_task(), which incorporates in_serving_softirq(). ]
) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.
