CVE-2022-49707

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2022-49707
In the Linux kernel, the following vulnerability has been resolved: ext4: add reserved GDT blocks check We capture a NULL pointer issue when resizing a corrupt ext4 image which is freshly clear resize_inode feature (not run e2fsck). It could be simply reproduced by following steps. The problem is because of the resize_inode feature was cleared, and it will convert the filesystem to meta_bg mode in ext4_resize_fs(), but the es->s_reserved_gdt_blocks was not reduced to zero, so could we mistakenly call reserve_backup_gdb() and passing an uninitialized resize_inode to it when adding new group descriptors. mkfs.ext4 /dev/sda 3G tune2fs -O ^resize_inode /dev/sda #forget to run requested e2fsck mount /dev/sda /mnt resize2fs /dev/sda 8G ======== BUG: kernel NULL pointer dereference, address: 0000000000000028 CPU: 19 PID: 3243 Comm: resize2fs Not tainted 5.18.0-rc7-00001-gfde086c5ebfd #748 ... RIP: 0010:ext4_flex_group_add+0xe08/0x2570 ... Call Trace: <TASK> ext4_resize_fs+0xbec/0x1660 __ext4_ioctl+0x1749/0x24e0 ext4_ioctl+0x12/0x20 __x64_sys_ioctl+0xa6/0x110 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f2dd739617b ======== The fix is simple, add a check in ext4_resize_begin() to make sure that the es->s_reserved_gdt_blocks is zero when the resize_inode feature is disabled.

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/0dc2fca8e4f9ac4a40e8424a10163369cca0cc06 Patch
https://git.kernel.org/stable/c/33b1bba31f4c784d33d2c2517964bdccdc9204cd Patch
https://git.kernel.org/stable/c/7c921328ac760bba780bdace41f4cd045f7f1405 Patch
https://git.kernel.org/stable/c/af75c481a2e45e70f62f5942c93695e95bf7bd21 Patch
https://git.kernel.org/stable/c/b55c3cd102a6f48b90e61c44f7f3dda8c290c694 Patch
https://git.kernel.org/stable/c/b9747263b13e5290ac4d63bec47e38f701303cad Patch
https://git.kernel.org/stable/c/bfd004a1d3a062aac300523d406ac1f3e5f1a82c Patch
https://git.kernel.org/stable/c/fba54289176702a7caac0b64738406775817f451 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:5.19:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.19:rc2:*:*:*:*:*:*
History

11 Mar 2025, 22:28

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/0dc2fca8e4f9ac4a40e8424a10163369cca0cc06 - () https://git.kernel.org/stable/c/0dc2fca8e4f9ac4a40e8424a10163369cca0cc06 - Patch
References () https://git.kernel.org/stable/c/33b1bba31f4c784d33d2c2517964bdccdc9204cd - () https://git.kernel.org/stable/c/33b1bba31f4c784d33d2c2517964bdccdc9204cd - Patch
References () https://git.kernel.org/stable/c/7c921328ac760bba780bdace41f4cd045f7f1405 - () https://git.kernel.org/stable/c/7c921328ac760bba780bdace41f4cd045f7f1405 - Patch
References () https://git.kernel.org/stable/c/af75c481a2e45e70f62f5942c93695e95bf7bd21 - () https://git.kernel.org/stable/c/af75c481a2e45e70f62f5942c93695e95bf7bd21 - Patch
References () https://git.kernel.org/stable/c/b55c3cd102a6f48b90e61c44f7f3dda8c290c694 - () https://git.kernel.org/stable/c/b55c3cd102a6f48b90e61c44f7f3dda8c290c694 - Patch
References () https://git.kernel.org/stable/c/b9747263b13e5290ac4d63bec47e38f701303cad - () https://git.kernel.org/stable/c/b9747263b13e5290ac4d63bec47e38f701303cad - Patch
References () https://git.kernel.org/stable/c/bfd004a1d3a062aac300523d406ac1f3e5f1a82c - () https://git.kernel.org/stable/c/bfd004a1d3a062aac300523d406ac1f3e5f1a82c - Patch
References () https://git.kernel.org/stable/c/fba54289176702a7caac0b64738406775817f451 - () https://git.kernel.org/stable/c/fba54289176702a7caac0b64738406775817f451 - Patch
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5
CWE CWE-476
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: agregar bloques GDT reservados comprobar Capturamos un problema de puntero NULL al cambiar el tamaño de una imagen ext4 corrupta que recién borra la característica resize_inode (no ejecuta e2fsck). Podría reproducirse simplemente siguiendo los pasos. El problema se debe a que se borró la característica resize_inode y convertirá el sistema de archivos al modo meta_bg en ext4_resize_fs(), pero es-&gt;s_reserved_gdt_blocks no se redujo a cero, por lo que podríamos llamar por error a reserve_backup_gdb() y pasarle un resize_inode no inicializado al agregar nuevos descriptores de grupo. mkfs.ext4 /dev/sda 3G tune2fs -O ^resize_inode /dev/sda #olvidé ejecutar el montaje e2fsck solicitado /dev/sda /mnt resize2fs /dev/sda 8G ======== ERROR: desreferencia de puntero NULL del núcleo, dirección: 0000000000000028 CPU: 19 PID: 3243 Comm: resize2fs No contaminado 5.18.0-rc7-00001-gfde086c5ebfd #748 ... RIP: 0010:ext4_flex_group_add+0xe08/0x2570 ... Seguimiento de llamadas: ext4_resize_fs+0xbec/0x1660 __ext4_ioctl+0x1749/0x24e0 ext4_ioctl+0x12/0x20 __x64_sys_ioctl+0xa6/0x110 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f2dd739617b ======== La solución es simple, agregue una comprobación en ext4_resize_begin() para asegurarse de que es-&gt;s_reserved_gdt_blocks sea cero cuando la función resize_inode esté deshabilitada.
First Time Linux linux Kernel
Linux
CPE cpe:2.3:o:linux:linux_kernel:5.19:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.19:rc1:*:*:*:*:*:*

26 Feb 2025, 07:01

Type Values Removed Values Added
New CVE
Information

Published : 2025-02-26 07:01

Updated : 2025-03-11 22:28

NVD link : CVE-2022-49707

Mitre link : CVE-2022-49707

CVE.ORG link : CVE-2022-49707

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-476

NULL Pointer Dereference