CVE-2024-42126

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2024-42126
In the Linux kernel, the following vulnerability has been resolved: powerpc: Avoid nmi_enter/nmi_exit in real mode interrupt. nmi_enter()/nmi_exit() touches per cpu variables which can lead to kernel crash when invoked during real mode interrupt handling (e.g. early HMI/MCE interrupt handler) if percpu allocation comes from vmalloc area. Early HMI/MCE handlers are called through DEFINE_INTERRUPT_HANDLER_NMI() wrapper which invokes nmi_enter/nmi_exit calls. We don't see any issue when percpu allocation is from the embedded first chunk. However with CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK enabled there are chances where percpu allocation can come from the vmalloc area. With kernel command line "percpu_alloc=page" we can force percpu allocation to come from vmalloc area and can see kernel crash in machine_check_early: [ 1.215714] NIP [c000000000e49eb4] rcu_nmi_enter+0x24/0x110 [ 1.215717] LR [c0000000000461a0] machine_check_early+0xf0/0x2c0 [ 1.215719] --- interrupt: 200 [ 1.215720] [c000000fffd73180] [0000000000000000] 0x0 (unreliable) [ 1.215722] [c000000fffd731b0] [0000000000000000] 0x0 [ 1.215724] [c000000fffd73210] [c000000000008364] machine_check_early_common+0x134/0x1f8 Fix this by avoiding use of nmi_enter()/nmi_exit() in real mode if percpu first chunk is not embedded.

5.5 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://git.kernel.org/stable/c/0db880fc865ffb522141ced4bfa66c12ab1fbb70 Patch
https://git.kernel.org/stable/c/0f37946c62c48a907625348cbc720a7a0c547d1e Patch
https://git.kernel.org/stable/c/2c78c9411e685dbc9eac8c2845111b03501975b8 Patch
https://git.kernel.org/stable/c/8d3f83dfb23674540c827a8d65fba20aa300b252 Patch
https://git.kernel.org/stable/c/e2afb26615adf6c3ceaaa7732aa839bcd587a057 Patch
https://git.kernel.org/stable/c/fb6675db04c4b79883373edc578d5df7bbc84848 Patch
https://git.kernel.org/stable/c/0db880fc865ffb522141ced4bfa66c12ab1fbb70 Patch
https://git.kernel.org/stable/c/0f37946c62c48a907625348cbc720a7a0c547d1e Patch
https://git.kernel.org/stable/c/2c78c9411e685dbc9eac8c2845111b03501975b8 Patch
https://git.kernel.org/stable/c/8d3f83dfb23674540c827a8d65fba20aa300b252 Patch
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
History

06 Oct 2025, 17:15

Type Values Removed Values Added
CWE NVD-CWE-noinfo
First Time Linux linux Kernel
Linux
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5
References () https://git.kernel.org/stable/c/0db880fc865ffb522141ced4bfa66c12ab1fbb70 - () https://git.kernel.org/stable/c/0db880fc865ffb522141ced4bfa66c12ab1fbb70 - Patch
References () https://git.kernel.org/stable/c/0f37946c62c48a907625348cbc720a7a0c547d1e - () https://git.kernel.org/stable/c/0f37946c62c48a907625348cbc720a7a0c547d1e - Patch
References () https://git.kernel.org/stable/c/2c78c9411e685dbc9eac8c2845111b03501975b8 - () https://git.kernel.org/stable/c/2c78c9411e685dbc9eac8c2845111b03501975b8 - Patch
References () https://git.kernel.org/stable/c/8d3f83dfb23674540c827a8d65fba20aa300b252 - () https://git.kernel.org/stable/c/8d3f83dfb23674540c827a8d65fba20aa300b252 - Patch
References () https://git.kernel.org/stable/c/e2afb26615adf6c3ceaaa7732aa839bcd587a057 - () https://git.kernel.org/stable/c/e2afb26615adf6c3ceaaa7732aa839bcd587a057 - Patch
References () https://git.kernel.org/stable/c/fb6675db04c4b79883373edc578d5df7bbc84848 - () https://git.kernel.org/stable/c/fb6675db04c4b79883373edc578d5df7bbc84848 - Patch

21 Nov 2024, 09:33

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/0db880fc865ffb522141ced4bfa66c12ab1fbb70 - () https://git.kernel.org/stable/c/0db880fc865ffb522141ced4bfa66c12ab1fbb70 -
References () https://git.kernel.org/stable/c/0f37946c62c48a907625348cbc720a7a0c547d1e - () https://git.kernel.org/stable/c/0f37946c62c48a907625348cbc720a7a0c547d1e -
References () https://git.kernel.org/stable/c/2c78c9411e685dbc9eac8c2845111b03501975b8 - () https://git.kernel.org/stable/c/2c78c9411e685dbc9eac8c2845111b03501975b8 -
References () https://git.kernel.org/stable/c/8d3f83dfb23674540c827a8d65fba20aa300b252 - () https://git.kernel.org/stable/c/8d3f83dfb23674540c827a8d65fba20aa300b252 -

19 Aug 2024, 05:15

Type Values Removed Values Added
References
  • () https://git.kernel.org/stable/c/e2afb26615adf6c3ceaaa7732aa839bcd587a057 -
  • () https://git.kernel.org/stable/c/fb6675db04c4b79883373edc578d5df7bbc84848 -

30 Jul 2024, 13:32

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: powerpc: Evite nmi_enter/nmi_exit en interrupción en modo real. nmi_enter()/nmi_exit() toca variables por CPU que pueden provocar un fallo del kernel cuando se invoca durante el manejo de interrupciones en modo real (por ejemplo, el controlador de interrupciones HMI/MCE temprano) si la asignación de percpu proviene del área vmalloc. Los primeros controladores HMI/MCE se llaman a través del contenedor DEFINE_INTERRUPT_HANDLER_NMI() que invoca llamadas nmi_enter/nmi_exit. No vemos ningún problema cuando la asignación de percpu proviene del primer fragmento integrado. Sin embargo, con CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK habilitado, hay posibilidades de que la asignación de percpu pueda provenir del área vmalloc. Con la línea de comando del kernel "percpu_alloc=page" podemos forzar que la asignación de percpu provenga del área vmalloc y podemos ver el fallo del kernel en machine_check_early: [1.215714] NIP [c000000000e49eb4] rcu_nmi_enter+0x24/0x110 [1.215717] LR [c0000000000461a0] check_early+0xf0/ 0x2c0 [1.215719] --- interrupción: 200 [ 1.215720] [c000000fffd73180] [0000000000000000] 0x0 (no confiable) [ 1.215722] [c000000fffd731b0] 000] 0x0 [ 1.215724] [c000000fffd73210] [c000000000008364] machine_check_early_common+0x134/0x1f8 Solucionar esto mediante evitando el uso de nmi_enter()/nmi_exit() en modo real si el primer fragmento de percpu no está incrustado.

30 Jul 2024, 08:15

Type Values Removed Values Added
New CVE
Information

Published : 2024-07-30 08:15

Updated : 2025-10-06 17:15

NVD link : CVE-2024-42126

Mitre link : CVE-2024-42126

CVE.ORG link : CVE-2024-42126

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
NVD-CWE-noinfo