CVE-2022-49171

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2022-49171
In the Linux kernel, the following vulnerability has been resolved: ext4: don't BUG if someone dirty pages without asking ext4 first [un]pin_user_pages_remote is dirtying pages without properly warning the file system in advance. A related race was noted by Jan Kara in 2018[1]; however, more recently instead of it being a very hard-to-hit race, it could be reliably triggered by process_vm_writev(2) which was discovered by Syzbot[2]. This is technically a bug in mm/gup.c, but arguably ext4 is fragile in that if some other kernel subsystem dirty pages without properly notifying the file system using page_mkwrite(), ext4 will BUG, while other file systems will not BUG (although data will still be lost). So instead of crashing with a BUG, issue a warning (since there may be potential data loss) and just mark the page as clean to avoid unprivileged denial of service attacks until the problem can be properly fixed. More discussion and background can be found in the thread starting at [2]. [1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz [2] https://lore.kernel.org/r/Yg0m6IjcNmfaSokM@google.com

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/0d3a6926f7e8be3c897fa46216ce13b119a9f56a Patch
https://git.kernel.org/stable/c/330d0e44fc5a47c27df958ecdd4693a3cb1d8b81 Patch
https://git.kernel.org/stable/c/343117559ef41e992e326f7a92da1a8f254dfa8c Patch
https://git.kernel.org/stable/c/5a016c053f426a73752c3b41b60b497b58694d48 Patch
https://git.kernel.org/stable/c/5db60e76edf5680ff1f3a7221036fc44b308f146 Patch
https://git.kernel.org/stable/c/677c9d30e8487bee6c8e3b034070319d98f6e203 Patch
https://git.kernel.org/stable/c/a0856764dc1276ad2dc7891288c2e9246bf11a37 Patch
https://git.kernel.org/stable/c/cc5095747edfb054ca2068d01af20be3fcc3634f Patch
https://git.kernel.org/stable/c/d666dfaa571465a19f014534a214c255ea33f301 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:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
History

23 Sep 2025, 13:39

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: no generar ERRORES si alguien ensucia páginas sin preguntar primero a ext4 [un]pin_user_pages_remote está ensuciando páginas sin advertir adecuadamente al sistema de archivos con anticipación. Jan Kara notó una ejecución relacionada en 2018[1]; sin embargo, más recientemente, en lugar de ser una ejecución muy difícil de alcanzar, podría ser activada de manera confiable por process_vm_writev(2) que fue descubierto por Syzbot[2]. Técnicamente, esto es un error en mm/gup.c, pero podría decirse que ext4 es frágil en el sentido de que si algún otro subsistema del kernel ensucia páginas sin notificar adecuadamente al sistema de archivos usando page_mkwrite(), ext4 generará ERRORES, mientras que otros sistemas de archivos no generarán ERRORES (aunque aún se perderán datos). Entonces, en lugar de bloquearse con un ERROR, emita una advertencia (ya que puede haber una posible pérdida de datos) y simplemente marque la página como limpia para evitar ataques de denegación de servicio sin privilegios hasta que el problema pueda solucionarse correctamente. Se puede encontrar más discusión y antecedentes en el hilo que comienza en [2]. [1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz [2] https://lore.kernel.org/r/Yg0m6IjcNmfaSokM@google.com
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
CWE CWE-617
References () https://git.kernel.org/stable/c/0d3a6926f7e8be3c897fa46216ce13b119a9f56a - () https://git.kernel.org/stable/c/0d3a6926f7e8be3c897fa46216ce13b119a9f56a - Patch
References () https://git.kernel.org/stable/c/330d0e44fc5a47c27df958ecdd4693a3cb1d8b81 - () https://git.kernel.org/stable/c/330d0e44fc5a47c27df958ecdd4693a3cb1d8b81 - Patch
References () https://git.kernel.org/stable/c/343117559ef41e992e326f7a92da1a8f254dfa8c - () https://git.kernel.org/stable/c/343117559ef41e992e326f7a92da1a8f254dfa8c - Patch
References () https://git.kernel.org/stable/c/5a016c053f426a73752c3b41b60b497b58694d48 - () https://git.kernel.org/stable/c/5a016c053f426a73752c3b41b60b497b58694d48 - Patch
References () https://git.kernel.org/stable/c/5db60e76edf5680ff1f3a7221036fc44b308f146 - () https://git.kernel.org/stable/c/5db60e76edf5680ff1f3a7221036fc44b308f146 - Patch
References () https://git.kernel.org/stable/c/677c9d30e8487bee6c8e3b034070319d98f6e203 - () https://git.kernel.org/stable/c/677c9d30e8487bee6c8e3b034070319d98f6e203 - Patch
References () https://git.kernel.org/stable/c/a0856764dc1276ad2dc7891288c2e9246bf11a37 - () https://git.kernel.org/stable/c/a0856764dc1276ad2dc7891288c2e9246bf11a37 - Patch
References () https://git.kernel.org/stable/c/cc5095747edfb054ca2068d01af20be3fcc3634f - () https://git.kernel.org/stable/c/cc5095747edfb054ca2068d01af20be3fcc3634f - Patch
References () https://git.kernel.org/stable/c/d666dfaa571465a19f014534a214c255ea33f301 - () https://git.kernel.org/stable/c/d666dfaa571465a19f014534a214c255ea33f301 - Patch
First Time Linux linux Kernel
Linux

26 Feb 2025, 07:00

Type Values Removed Values Added
New CVE
Information

Published : 2025-02-26 07:00

Updated : 2025-09-23 13:39

NVD link : CVE-2022-49171

Mitre link : CVE-2022-49171

CVE.ORG link : CVE-2022-49171

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-617

Reachable Assertion