CVE-2024-42102

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2024-42102
In the Linux kernel, the following vulnerability has been resolved: Revert "mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again" Patch series "mm: Avoid possible overflows in dirty throttling". Dirty throttling logic assumes dirty limits in page units fit into 32-bits. This patch series makes sure this is true (see patch 2/2 for more details). This patch (of 2): This reverts commit 9319b647902cbd5cc884ac08a8a6d54ce111fc78. The commit is broken in several ways. Firstly, the removed (u64) cast from the multiplication will introduce a multiplication overflow on 32-bit archs if wb_thresh * bg_thresh >= 1<<32 (which is actually common - the default settings with 4GB of RAM will trigger this). Secondly, the div64_u64() is unnecessarily expensive on 32-bit archs. We have div64_ul() in case we want to be safe & cheap. Thirdly, if dirty thresholds are larger than 1<<32 pages, then dirty balancing is going to blow up in many other spectacular ways anyway so trying to fix one possible overflow is just moot.

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/000099d71648504fb9c7a4616f92c2b70c3e44ec Patch
https://git.kernel.org/stable/c/145faa3d03688cbb7bbaaecbd84c01539852942c Patch
https://git.kernel.org/stable/c/23a28f5f3f6ca1e4184bd0e9631cd0944cf1c807 Patch
https://git.kernel.org/stable/c/253f9ea7e8e53a5176bd80ceb174907b10724c1a Patch
https://git.kernel.org/stable/c/2820005edae13b140f2d54267d1bd6bb23915f59 Patch
https://git.kernel.org/stable/c/30139c702048f1097342a31302cbd3d478f50c63 Patch
https://git.kernel.org/stable/c/cbbe17a324437c0ff99881a3ee453da45b228a00 Patch
https://git.kernel.org/stable/c/f6620df12cb6bdcad671d269debbb23573502f9d 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:*:*:*:*:*:*:*:*
History

21 Aug 2024, 20:48

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5
First Time Linux linux Kernel
Linux
References () https://git.kernel.org/stable/c/000099d71648504fb9c7a4616f92c2b70c3e44ec - () https://git.kernel.org/stable/c/000099d71648504fb9c7a4616f92c2b70c3e44ec - Patch
References () https://git.kernel.org/stable/c/145faa3d03688cbb7bbaaecbd84c01539852942c - () https://git.kernel.org/stable/c/145faa3d03688cbb7bbaaecbd84c01539852942c - Patch
References () https://git.kernel.org/stable/c/23a28f5f3f6ca1e4184bd0e9631cd0944cf1c807 - () https://git.kernel.org/stable/c/23a28f5f3f6ca1e4184bd0e9631cd0944cf1c807 - Patch
References () https://git.kernel.org/stable/c/253f9ea7e8e53a5176bd80ceb174907b10724c1a - () https://git.kernel.org/stable/c/253f9ea7e8e53a5176bd80ceb174907b10724c1a - Patch
References () https://git.kernel.org/stable/c/2820005edae13b140f2d54267d1bd6bb23915f59 - () https://git.kernel.org/stable/c/2820005edae13b140f2d54267d1bd6bb23915f59 - Patch
References () https://git.kernel.org/stable/c/30139c702048f1097342a31302cbd3d478f50c63 - () https://git.kernel.org/stable/c/30139c702048f1097342a31302cbd3d478f50c63 - Patch
References () https://git.kernel.org/stable/c/cbbe17a324437c0ff99881a3ee453da45b228a00 - () https://git.kernel.org/stable/c/cbbe17a324437c0ff99881a3ee453da45b228a00 - Patch
References () https://git.kernel.org/stable/c/f6620df12cb6bdcad671d269debbb23573502f9d - () https://git.kernel.org/stable/c/f6620df12cb6bdcad671d269debbb23573502f9d - Patch
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
CWE CWE-369

30 Jul 2024, 13:32

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: Revertir "mm/writeback: corrige la posible división por cero en wb_dirty_limits(), nuevamente" Patch series "mm: evita posibles desbordamientos en la aceleración sucia". La lógica de limitación sucia supone que los límites sucios en las unidades de páginas caben en 32 bits. Esta serie de parches garantiza que esto sea cierto (consulte el parche 2/2 para obtener más detalles). Este parche (de 2): esto revierte la confirmación 9319b647902cbd5cc884ac08a8a6d54ce111fc78. El compromiso se rompe de varias maneras. En primer lugar, la conversión eliminada (u64) de la multiplicación introducirá un desbordamiento de multiplicación en arcos de 32 bits si wb_thresh * bg_thresh &gt;= 1&lt;&lt;32 (lo cual es realmente común; la configuración predeterminada con 4 GB de RAM activará esto). En segundo lugar, div64_u64() es innecesariamente caro en arcos de 32 bits. Tenemos div64_ul() en caso de que queramos ser seguros y económicos. En tercer lugar, si los umbrales sucios son mayores que 1&lt;&lt;32 páginas, entonces el equilibrio sucio explotará de muchas otras maneras espectaculares de todos modos, por lo que intentar solucionar un posible desbordamiento es discutible.

30 Jul 2024, 08:15

Type Values Removed Values Added
New CVE
Information

Published : 2024-07-30 08:15

Updated : 2024-08-21 20:48

NVD link : CVE-2024-42102

Mitre link : CVE-2024-42102

CVE.ORG link : CVE-2024-42102

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-369

Divide By Zero