CVE-2023-52622
ext4: avoid online resizing failures due to oversized flex bg
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
In the Linux kernel, the following vulnerability has been resolved:
ext4: avoid online resizing failures due to oversized flex bg
When we online resize an ext4 filesystem with a oversized flexbg_size,
mkfs.ext4 -F -G 67108864 $dev -b 4096 100M
mount $dev $dir
resize2fs $dev 16G
the following WARN_ON is triggered:
==================================================================
WARNING: CPU: 0 PID: 427 at mm/page_alloc.c:4402 __alloc_pages+0x411/0x550
Modules linked in: sg(E)
CPU: 0 PID: 427 Comm: resize2fs Tainted: G E 6.6.0-rc5+ #314
RIP: 0010:__alloc_pages+0x411/0x550
Call Trace:
<TASK>
__kmalloc_large_node+0xa2/0x200
__kmalloc+0x16e/0x290
ext4_resize_fs+0x481/0xd80
__ext4_ioctl+0x1616/0x1d90
ext4_ioctl+0x12/0x20
__x64_sys_ioctl+0xf0/0x150
do_syscall_64+0x3b/0x90
==================================================================
This is because flexbg_size is too large and the size of the new_group_data
array to be allocated exceeds MAX_ORDER. Currently, the minimum value of
MAX_ORDER is 8, the minimum value of PAGE_SIZE is 4096, the corresponding
maximum number of groups that can be allocated is:
(PAGE_SIZE << MAX_ORDER) / sizeof(struct ext4_new_group_data) ≈ 21845
And the value that is down-aligned to the power of 2 is 16384. Therefore,
this value is defined as MAX_RESIZE_BG, and the number of groups added
each time does not exceed this value during resizing, and is added multiple
times to complete the online resizing. The difference is that the metadata
in a flex_bg may be more dispersed.
En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: evita fallos de cambio de tamaño en línea debido a flex bg sobredimensionado Cuando redimensionamos en línea un sistema de archivos ext4 con un flexbg_size sobredimensionado, mkfs.ext4 -F -G 67108864 $dev -b 4096 100M mount $dev $dir resize2fs $dev 16G se activa el siguiente WARN_ON: ===================================== ============================== ADVERTENCIA: CPU: 0 PID: 427 en mm/page_alloc.c:4402 __alloc_pages+0x411/ 0x550 Módulos vinculados en: sg(E) CPU: 0 PID: 427 Comm: resize2fs Contaminado: GE 6.6.0-rc5+ #314 RIP: 0010:__alloc_pages+0x411/0x550 Seguimiento de llamadas: __kmalloc_large_node+0xa2/0x200 __kmalloc+ 0x16e/0x290 text4_resize_fs+0x481/0xd80 __ext4_ioctl+0x1616/0x1d90 text4_ioctl+0x12/0x20 __x64_sys_ioctl+0xf0/0x150 do_syscall_64+0x3b/0x90 ======== =============== ============================================ Esto se debe a que flexbg_size también lo es grande y el tamaño de la matriz new_group_data que se asignará excede MAX_ORDER. Actualmente, el valor mínimo de MAX_ORDER es 8, el valor mínimo de PAGE_SIZE es 4096, el número máximo correspondiente de grupos que se pueden asignar es: (PAGE_SIZE << MAX_ORDER) / sizeof(struct text4_new_group_data) ? 21845 Y el valor que está hacia abajo -alineado a la potencia de 2 es 16384. Por lo tanto, este valor se define como MAX_RESIZE_BG, y el número de grupos agregados cada vez no excede este valor durante el cambio de tamaño y se agrega varias veces para completar el cambio de tamaño en línea. La diferencia es que los metadatos en flex_bg pueden estar más dispersos.
CVSS Scores
SSVC
- Decision:Track
Timeline
- 2024-03-06 CVE Reserved
- 2024-03-26 CVE Published
- 2024-03-27 EPSS Updated
- 2024-12-19 CVE Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
- CWE-131: Incorrect Calculation of Buffer Size
CAPEC
References (12)
URL | Tag | Source |
---|---|---|
https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html | ||
https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html |
URL | Date | SRC |
---|
URL | Date | SRC |
---|---|---|
https://access.redhat.com/security/cve/CVE-2023-52622 | 2024-11-12 | |
https://bugzilla.redhat.com/show_bug.cgi?id=2271688 | 2024-11-12 |
Affected Vendors, Products, and Versions
Vendor | Product | Version | Other | Status | ||||||
---|---|---|---|---|---|---|---|---|---|---|
Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | < 4.19.307 Search vendor "Linux" for product "Linux Kernel" and version " < 4.19.307" | en |
Affected
| ||||||
Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | < 5.4.269 Search vendor "Linux" for product "Linux Kernel" and version " < 5.4.269" | en |
Affected
| ||||||
Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | < 5.10.210 Search vendor "Linux" for product "Linux Kernel" and version " < 5.10.210" | en |
Affected
| ||||||
Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | < 5.15.149 Search vendor "Linux" for product "Linux Kernel" and version " < 5.15.149" | en |
Affected
| ||||||
Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | < 6.1.77 Search vendor "Linux" for product "Linux Kernel" and version " < 6.1.77" | en |
Affected
| ||||||
Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | < 6.6.16 Search vendor "Linux" for product "Linux Kernel" and version " < 6.6.16" | en |
Affected
| ||||||
Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | < 6.7.4 Search vendor "Linux" for product "Linux Kernel" and version " < 6.7.4" | en |
Affected
| ||||||
Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | < 6.8 Search vendor "Linux" for product "Linux Kernel" and version " < 6.8" | en |
Affected
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