CVE-2024-49883

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2024-49883
In the Linux kernel, the following vulnerability has been resolved: ext4: aovid use-after-free in ext4_ext_insert_extent() As Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is reallocated in ext4_ext_create_new_leaf(), we'll use the stale path and cause UAF. Below is a sample trace with dummy values: ext4_ext_insert_extent path = *ppath = 2000 ext4_ext_create_new_leaf(ppath) ext4_find_extent(ppath) path = *ppath = 2000 if (depth > path[0].p_maxdepth) kfree(path = 2000); *ppath = path = NULL; path = kcalloc() = 3000 *ppath = 3000; return path; /* here path is still 2000, UAF! */ eh = path[depth].p_hdr ================================================================== BUG: KASAN: slab-use-after-free in ext4_ext_insert_extent+0x26d4/0x3330 Read of size 8 at addr ffff8881027bf7d0 by task kworker/u36:1/179 CPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 Not tainted 6.11.0-rc2-dirty #866 Call Trace: <TASK> ext4_ext_insert_extent+0x26d4/0x3330 ext4_ext_map_blocks+0xe22/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 [...] Allocated by task 179: ext4_find_extent+0x81c/0x1f70 ext4_ext_map_blocks+0x146/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 ext4_writepages+0x26d/0x4e0 do_writepages+0x175/0x700 [...] Freed by task 179: kfree+0xcb/0x240 ext4_find_extent+0x7c0/0x1f70 ext4_ext_insert_extent+0xa26/0x3330 ext4_ext_map_blocks+0xe22/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 ext4_writepages+0x26d/0x4e0 do_writepages+0x175/0x700 [...] ================================================================== So use *ppath to update the path to avoid the above problem.

7.8 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://git.kernel.org/stable/c/51db04892a993cace63415be99848970a0f15ef2 Patch
https://git.kernel.org/stable/c/5e811066c5ab709b070659197dccfb80ab650ddd Patch
https://git.kernel.org/stable/c/8162ee5d94b8c0351be0a9321be134872a7654a1 Patch
https://git.kernel.org/stable/c/975ca06f3fd154c5f7742083e7b2574c57d1c0c3
https://git.kernel.org/stable/c/9df59009dfc6d9fc1bd9ddf6c5ab6e56d6ed887a Patch
https://git.kernel.org/stable/c/a164f3a432aae62ca23d03e6d926b122ee5b860d Patch
https://git.kernel.org/stable/c/beb7b66fb489041c50c6473100b383f7a51648fc Patch
https://git.kernel.org/stable/c/bfed082ce4b1ce6349b05c09a0fa4f3da35ecb1b Patch
https://git.kernel.org/stable/c/e17ebe4fdd7665c93ae9459ba40fcdfb76769ac1
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:*:*:*:*:*:*:*:*
History

08 Nov 2024, 16:15

Type Values Removed Values Added
References
  • () https://git.kernel.org/stable/c/975ca06f3fd154c5f7742083e7b2574c57d1c0c3 -
  • () https://git.kernel.org/stable/c/e17ebe4fdd7665c93ae9459ba40fcdfb76769ac1 -

25 Oct 2024, 14:43

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/51db04892a993cace63415be99848970a0f15ef2 - () https://git.kernel.org/stable/c/51db04892a993cace63415be99848970a0f15ef2 - Patch
References () https://git.kernel.org/stable/c/5e811066c5ab709b070659197dccfb80ab650ddd - () https://git.kernel.org/stable/c/5e811066c5ab709b070659197dccfb80ab650ddd - Patch
References () https://git.kernel.org/stable/c/8162ee5d94b8c0351be0a9321be134872a7654a1 - () https://git.kernel.org/stable/c/8162ee5d94b8c0351be0a9321be134872a7654a1 - Patch
References () https://git.kernel.org/stable/c/9df59009dfc6d9fc1bd9ddf6c5ab6e56d6ed887a - () https://git.kernel.org/stable/c/9df59009dfc6d9fc1bd9ddf6c5ab6e56d6ed887a - Patch
References () https://git.kernel.org/stable/c/a164f3a432aae62ca23d03e6d926b122ee5b860d - () https://git.kernel.org/stable/c/a164f3a432aae62ca23d03e6d926b122ee5b860d - Patch
References () https://git.kernel.org/stable/c/beb7b66fb489041c50c6473100b383f7a51648fc - () https://git.kernel.org/stable/c/beb7b66fb489041c50c6473100b383f7a51648fc - Patch
References () https://git.kernel.org/stable/c/bfed082ce4b1ce6349b05c09a0fa4f3da35ecb1b - () https://git.kernel.org/stable/c/bfed082ce4b1ce6349b05c09a0fa4f3da35ecb1b - Patch
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 7.8
First Time Linux linux Kernel
Linux
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
CWE CWE-416

23 Oct 2024, 15:13

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: evitar use-after-free en ext4_ext_insert_extent() Como mencionó Ojaswin en Link, en ext4_ext_insert_extent(), si la ruta se reasigna en ext4_ext_create_new_leaf(), usaremos la ruta obsoleta y causaremos UAF. A continuación, se muestra un seguimiento de muestra con valores ficticios: ext4_ext_insert_extent path = *ppath = 2000 ext4_ext_create_new_leaf(ppath) ext4_find_extent(ppath) path = *ppath = 2000 if (depth &gt; path[0].p_maxdepth) kfree(path = 2000); *ppath = path = NULL; path = kcalloc() = 3000 *ppath = 3000; return path; /* aquí la ruta sigue siendo 2000, UAF! */ eh = path[depth].p_hdr ===================================================================== ERROR: KASAN: slab-use-after-free en ext4_ext_insert_extent+0x26d4/0x3330 Lectura de tamaño 8 en la dirección ffff8881027bf7d0 por la tarea kworker/u36:1/179 CPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 No contaminado 6.11.0-rc2-dirty #866 Seguimiento de llamadas: ext4_ext_insert_extent+0x26d4/0x3330 ext4_ext_map_blocks+0xe22/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 [...] Asignado por la tarea 179: ext4_find_extent+0x81c/0x1f70 ext4_ext_map_blocks+0x146/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 ext4_writepages+0x26d/0x4e0 do_writepages+0x175/0x700 [...] Liberado por la tarea 179: kfree+0xcb/0x240 ext4_find_extent+0x7c0/0x1f70 ext4_ext_insert_extent+0xa26/0x3330 ext4_ext_map_blocks+0xe22/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 ext4_writepages+0x26d/0x4e0 do_writepages+0x175/0x700 [...]================================================================== Así que use *ppath para actualizar el path para evitar el problema de arriba

21 Oct 2024, 18:15

Type Values Removed Values Added
New CVE
Information

Published : 2024-10-21 18:15

Updated : 2024-11-08 16:15

NVD link : CVE-2024-49883

Mitre link : CVE-2024-49883

CVE.ORG link : CVE-2024-49883

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-416

Use After Free