CVE-2022-50091

In the Linux kernel, the following vulnerability has been resolved: locking/csd_lock: Change csdlock_debug from early_param to __setup The csdlock_debug kernel-boot parameter is parsed by the early_param() function csdlock_debug(). If set, csdlock_debug() invokes static_branch_enable() to enable csd_lock_wait feature, which triggers a panic on arm64 for kernels built with CONFIG_SPARSEMEM=y and CONFIG_SPARSEMEM_VMEMMAP=n. With CONFIG_SPARSEMEM_VMEMMAP=n, __nr_to_section is called in static_key_enable() and returns NULL, resulting in a NULL dereference because mem_section is initialized only later in sparse_init(). This is also a problem for powerpc because early_param() functions are invoked earlier than jump_label_init(), also resulting in static_key_enable() failures. These failures cause the warning "static key 'xxx' used before call to jump_label_init()". Thus, early_param is too early for csd_lock_wait to run static_branch_enable(), so changes it to __setup to fix these.
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:*:*:*:*:*:*:*:*

History

18 Nov 2025, 02:11

Type Values Removed Values Added
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
References () https://git.kernel.org/stable/c/05de9e2e33b1625c71aee69e353fe906dd2be88a - () https://git.kernel.org/stable/c/05de9e2e33b1625c71aee69e353fe906dd2be88a - Patch
References () https://git.kernel.org/stable/c/9c9b26b0df270d4f9246e483a44686fca951a29c - () https://git.kernel.org/stable/c/9c9b26b0df270d4f9246e483a44686fca951a29c - Patch
References () https://git.kernel.org/stable/c/b480d1e9a8c11ecc1c99dc01814b28e3103bd0a0 - () https://git.kernel.org/stable/c/b480d1e9a8c11ecc1c99dc01814b28e3103bd0a0 - Patch
References () https://git.kernel.org/stable/c/d2cbdbe22b5f190055d2d0ae92e7454479343a30 - () https://git.kernel.org/stable/c/d2cbdbe22b5f190055d2d0ae92e7454479343a30 - Patch
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: locking/csd_lock: Cambiar csdlock_debug de early_param a __setup El parámetro csdlock_debug kernel-boot es analizado por la función early_param() csdlock_debug(). Si se establece, csdlock_debug() invoca static_branch_enable() para habilitar la función csd_lock_wait, que desencadena un pánico en arm64 para kernels compilados con CONFIG_SPARSEMEM=y y CONFIG_SPARSEMEM_VMEMMAP=n. Con CONFIG_SPARSEMEM_VMEMMAP=n, se llama a __nr_to_section en static_key_enable() y devuelve NULL, lo que resulta en una desreferencia NULL porque mem_section se inicializa solo más tarde en sparse_init(). Esto también representa un problema para PowerPC, ya que las funciones early_param() se invocan antes que jump_label_init(), lo que también provoca fallos en static_key_enable(). Estos fallos generan la advertencia "Clave estática 'xxx' usada antes de la llamada a jump_label_init()". Por lo tanto, early_param es demasiado pronto para que csd_lock_wait ejecute static_branch_enable(), por lo que se cambia a __setup para solucionarlos.
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.5
CWE CWE-476
First Time Linux
Linux linux Kernel

18 Jun 2025, 11:15

Type Values Removed Values Added
New CVE

Information

Published : 2025-06-18 11:15

Updated : 2025-11-18 02:11


NVD link : CVE-2022-50091

Mitre link : CVE-2022-50091

CVE.ORG link : CVE-2022-50091


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-476

NULL Pointer Dereference