CVE-2021-47333

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2021-47333
In the Linux kernel, the following vulnerability has been resolved: misc: alcor_pci: fix null-ptr-deref when there is no PCI bridge There is an issue with the ASPM(optional) capability checking function. A device might be attached to root complex directly, in this case, bus->self(bridge) will be NULL, thus priv->parent_pdev is NULL. Since alcor_pci_init_check_aspm(priv->parent_pdev) checks the PCI link's ASPM capability and populate parent_cap_off, which will be used later by alcor_pci_aspm_ctrl() to dynamically turn on/off device, what we can do here is to avoid checking the capability if we are on the root complex. This will make pdev_cap_off 0 and alcor_pci_aspm_ctrl() will simply return when bring called, effectively disable ASPM for the device. [ 1.246492] BUG: kernel NULL pointer dereference, address: 00000000000000c0 [ 1.248731] RIP: 0010:pci_read_config_byte+0x5/0x40 [ 1.253998] Call Trace: [ 1.254131] ? alcor_pci_find_cap_offset.isra.0+0x3a/0x100 [alcor_pci] [ 1.254476] alcor_pci_probe+0x169/0x2d5 [alcor_pci]

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/09d154990ca82d14aed2b72796f6c8845e2e605d Patch
https://git.kernel.org/stable/c/3ce3e45cc333da707d4d6eb433574b990bcc26f5 Patch
https://git.kernel.org/stable/c/58f69684ba03e5b0e0a3ae844a845280c0f06309 Patch
https://git.kernel.org/stable/c/717cf5ae52322ddbdf3ac2c584b34c5970b0d174 Patch
https://git.kernel.org/stable/c/d2639ffdcad463b358b6bef8645ff81715daffcb Patch
https://git.kernel.org/stable/c/09d154990ca82d14aed2b72796f6c8845e2e605d Patch
https://git.kernel.org/stable/c/3ce3e45cc333da707d4d6eb433574b990bcc26f5 Patch
https://git.kernel.org/stable/c/58f69684ba03e5b0e0a3ae844a845280c0f06309 Patch
https://git.kernel.org/stable/c/717cf5ae52322ddbdf3ac2c584b34c5970b0d174 Patch
https://git.kernel.org/stable/c/d2639ffdcad463b358b6bef8645ff81715daffcb 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:*:*:*:*:*:*:*:*
History

02 Apr 2025, 14:32

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/09d154990ca82d14aed2b72796f6c8845e2e605d - () https://git.kernel.org/stable/c/09d154990ca82d14aed2b72796f6c8845e2e605d - Patch
References () https://git.kernel.org/stable/c/3ce3e45cc333da707d4d6eb433574b990bcc26f5 - () https://git.kernel.org/stable/c/3ce3e45cc333da707d4d6eb433574b990bcc26f5 - Patch
References () https://git.kernel.org/stable/c/58f69684ba03e5b0e0a3ae844a845280c0f06309 - () https://git.kernel.org/stable/c/58f69684ba03e5b0e0a3ae844a845280c0f06309 - Patch
References () https://git.kernel.org/stable/c/717cf5ae52322ddbdf3ac2c584b34c5970b0d174 - () https://git.kernel.org/stable/c/717cf5ae52322ddbdf3ac2c584b34c5970b0d174 - Patch
References () https://git.kernel.org/stable/c/d2639ffdcad463b358b6bef8645ff81715daffcb - () https://git.kernel.org/stable/c/d2639ffdcad463b358b6bef8645ff81715daffcb - Patch
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
First Time Linux linux Kernel
Linux
CWE CWE-476

21 Nov 2024, 06:35

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/09d154990ca82d14aed2b72796f6c8845e2e605d - () https://git.kernel.org/stable/c/09d154990ca82d14aed2b72796f6c8845e2e605d -
References () https://git.kernel.org/stable/c/3ce3e45cc333da707d4d6eb433574b990bcc26f5 - () https://git.kernel.org/stable/c/3ce3e45cc333da707d4d6eb433574b990bcc26f5 -
References () https://git.kernel.org/stable/c/58f69684ba03e5b0e0a3ae844a845280c0f06309 - () https://git.kernel.org/stable/c/58f69684ba03e5b0e0a3ae844a845280c0f06309 -
References () https://git.kernel.org/stable/c/717cf5ae52322ddbdf3ac2c584b34c5970b0d174 - () https://git.kernel.org/stable/c/717cf5ae52322ddbdf3ac2c584b34c5970b0d174 -
References () https://git.kernel.org/stable/c/d2639ffdcad463b358b6bef8645ff81715daffcb - () https://git.kernel.org/stable/c/d2639ffdcad463b358b6bef8645ff81715daffcb -

31 Oct 2024, 16:35

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5
Summary
  • (es) En el kernel de Linux, se resolvió la siguiente vulnerabilidad: misc: alcor_pci: corrige null-ptr-deref cuando no hay un puente PCI. Hay un problema con la función de verificación de capacidad ASPM (opcional). Un dispositivo se puede conectar directamente al complejo root; en este caso, bus->self(bridge) será NULL, por lo tanto, priv->parent_pdev es NULL. Dado que alcor_pci_init_check_aspm(priv->parent_pdev) verifica la capacidad ASPM del enlace PCI y completa parent_cap_off, que será utilizado más adelante por alcor_pci_aspm_ctrl() para encender/apagar dinámicamente el dispositivo, lo que podemos hacer aquí es evitar verificar la capacidad si estamos encendidos. el complejo raíz. Esto hará que pdev_cap_off sea 0 y alcor_pci_aspm_ctrl() simplemente regrese cuando se llame a Bring, deshabilitando efectivamente ASPM para el dispositivo. [1.246492] BUG: desreferencia del puntero NULL del kernel, dirección: 00000000000000c0 [1.248731] RIP: 0010:pci_read_config_byte+0x5/0x40 [1.253998] Seguimiento de llamadas: [1.254131]? alcor_pci_find_cap_offset.isra.0+0x3a/0x100 [alcor_pci] [ 1.254476] alcor_pci_probe+0x169/0x2d5 [alcor_pci]

21 May 2024, 15:15

Type Values Removed Values Added
New CVE
Information

Published : 2024-05-21 15:15

Updated : 2025-04-02 14:32

NVD link : CVE-2021-47333

Mitre link : CVE-2021-47333

CVE.ORG link : CVE-2021-47333

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-476

NULL Pointer Dereference