CVE-2024-26756

md: Don't register sync_thread for reshape directly

Severity Score

"-"

*CVSS v-

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track

*SSVC

Descriptions

In the Linux kernel, the following vulnerability has been resolved:

md: Don't register sync_thread for reshape directly

Currently, if reshape is interrupted, then reassemble the array will
register sync_thread directly from pers->run(), in this case
'MD_RECOVERY_RUNNING' is set directly, however, there is no guarantee
that md_do_sync() will be executed, hence stop_sync_thread() will hang
because 'MD_RECOVERY_RUNNING' can't be cleared.

Last patch make sure that md_do_sync() will set MD_RECOVERY_DONE,
however, following hang can still be triggered by dm-raid test
shell/lvconvert-raid-reshape.sh occasionally:

[root@fedora ~]# cat /proc/1982/stack
[<0>] stop_sync_thread+0x1ab/0x270 [md_mod]
[<0>] md_frozen_sync_thread+0x5c/0xa0 [md_mod]
[<0>] raid_presuspend+0x1e/0x70 [dm_raid]
[<0>] dm_table_presuspend_targets+0x40/0xb0 [dm_mod]
[<0>] __dm_destroy+0x2a5/0x310 [dm_mod]
[<0>] dm_destroy+0x16/0x30 [dm_mod]
[<0>] dev_remove+0x165/0x290 [dm_mod]
[<0>] ctl_ioctl+0x4bb/0x7b0 [dm_mod]
[<0>] dm_ctl_ioctl+0x11/0x20 [dm_mod]
[<0>] vfs_ioctl+0x21/0x60
[<0>] __x64_sys_ioctl+0xb9/0xe0
[<0>] do_syscall_64+0xc6/0x230
[<0>] entry_SYSCALL_64_after_hwframe+0x6c/0x74

Meanwhile mddev->recovery is:
MD_RECOVERY_RUNNING |
MD_RECOVERY_INTR |
MD_RECOVERY_RESHAPE |
MD_RECOVERY_FROZEN

Fix this problem by remove the code to register sync_thread directly
from raid10 and raid5. And let md_check_recovery() to register
sync_thread.

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: md: No registre sync_thread para remodelar directamente Actualmente, si se interrumpe el proceso de remodelación, volver a ensamblar la matriz registrará sync_thread directamente desde pers->run(), en este caso 'MD_RECOVERY_RUNNING ' se configura directamente, sin embargo, no hay garantía de que md_do_sync() se ejecute, por lo tanto, stop_sync_thread() se bloqueará porque 'MD_RECOVERY_RUNNING' no se puede borrar. En el último parche, asegúrese de que md_do_sync() establezca MD_RECOVERY_DONE; sin embargo, dm-raid test shell/lvconvert-raid-reshape.sh ocasionalmente puede activar el siguiente bloqueo: [root@fedora ~]# cat /proc/1982/stack [<0>] stop_sync_thread+0x1ab/0x270 [md_mod] [<0>] md_frozen_sync_thread+0x5c/0xa0 [md_mod] [<0>] raid_presuspend+0x1e/0x70 [dm_raid] [<0>] dm_table_presuspend_targets+0x40/0xb0 [ dm_mod] [<0>] __dm_destroy+0x2a5/0x310 [dm_mod] [<0>] dm_destroy+0x16/0x30 [dm_mod] [<0>] dev_remove+0x165/0x290 [dm_mod] [<0>] ctl_ioctl+0x4bb/ 0x7b0 [dm_mod] [<0>] dm_ctl_ioctl+0x11/0x20 [dm_mod] [<0>] vfs_ioctl+0x21/0x60 [<0>] __x64_sys_ioctl+0xb9/0xe0 [<0>] do_syscall_64+0xc6/0x230 [<0 >] Entry_SYSCALL_64_after_hwframe+0x6c/0x74 Mientras tanto mddev->recovery es: MD_RECOVERY_RUNNING | MD_RECOVERY_INTR | MD_RECOVERY_RESHAPE | MD_RECOVERY_FROZEN Solucione este problema eliminando el código para registrar sync_thread directamente desde raid10 y raid5. Y deje que md_check_recovery() registre sync_thread.

*Credits: N/A

CVSS Scores

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Scope

Confidentiality

Integrity

Availability

* Common Vulnerability Scoring System

SSVC

Decision:Track

Exploitation

None

Automatable

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2024-02-19 CVE Reserved
2024-04-03 CVE Published
2024-04-04 EPSS Updated
2024-08-02 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CAPEC

References (3)

URL	Tag	Source
https://git.kernel.org/stable/c/f67055780caac6a99f43834795c43acf99eba6a6	Vuln. Introduced

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/stable/c/13b520fb62b772e408f9b79c5fe18ad414e90417	2024-03-01
https://git.kernel.org/stable/c/ad39c08186f8a0f221337985036ba86731d6aafe	2024-02-15

URL	Date	SRC

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"				>= 2.6.17 < 6.7.7 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.17 < 6.7.7"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 2.6.17 < 6.8 Search vendor "Linux" for product "Linux Kernel" and version " >= 2.6.17 < 6.8"		en		Affected