In the Linux kernel, the following vulnerability has been resolved: quota: flush quota_release_work upon quota writeback One of the paths quota writeback is called from is: freeze_super() sync_filesystem() ext4_sync_fs() dquot_writeback_dquots() Since we currently don't always flush the quota_release_work queue in this path, we can end up with the following race: 1. dquot are added to releasing_dquots list during regular operations. 2. FS Freeze starts, however, this does not flush the quota_release_work queue. 3. Freeze completes. 4. Kernel eventually tries to flush the workqueue while FS is frozen which hits a WARN_ON since transaction gets started during frozen state: ext4_journal_check_start+0x28/0x110 [ext4] (unreliable) __ext4_journal_start_sb+0x64/0x1c0 [ext4] ext4_release_dquot+0x90/0x1d0 [ext4] quota_release_workfn+0x43c/0x4d0 Which is the following line: WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE); Which ultimately results in generic/390 failing due to dmesg noise. This was detected on powerpc machine 15 cores. To avoid this, make sure to flush the workqueue during dquot_writeback_dquots() so we dont have any pending workitems after freeze.
En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: quota: vaciar quota_release_work al reescribir la cuota Una de las rutas desde las que se llama a la reescritura de cuota es: freeze_super() sync_filesystem() ext4_sync_fs() dquot_writeback_dquots() Dado que actualmente no siempre vaciamos la cola quota_release_work en esta ruta, podemos terminar con la siguiente ejecución: 1. dquot se agregan a la lista release_dquots durante las operaciones regulares. 2. FS Freeze comienza, sin embargo, esto no vacía la cola quota_release_work. 3. Freeze se completa. 4. El kernel finalmente intenta vaciar la cola de trabajo mientras FS está congelado, lo que genera un WARN_ON ya que la transacción se inicia durante el estado congelado: ext4_journal_check_start+0x28/0x110 [ext4] (no confiable) __ext4_journal_start_sb+0x64/0x1c0 [ext4] ext4_release_dquot+0x90/0x1d0 [ext4] quota_release_workfn+0x43c/0x4d0 Que es la siguiente línea: WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE); Lo que finalmente da como resultado que generic/390 falle debido al ruido de dmesg. Esto se detectó en una máquina PowerPC de 15 núcleos. Para evitar esto, asegúrese de vaciar la cola de trabajo durante dquot_writeback_dquots() para que no tengamos ningún elemento de trabajo pendiente después del congelamiento.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
| Attack Vector | LOCAL |
|---|---|
| Attack Complexity | LOW |
| Privileges Required | LOW |
| User Interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality Impact | NONE |
| Integrity Impact | NONE |
| Availability Impact | HIGH |
| Source | Type | Description |
|---|---|---|
| [email protected] | Primary |
en
NVD-CWE-noinfo
|
| Vendor | Product | Version | Update | Type |
|---|---|---|---|---|
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36befb0c0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36941a8c0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd3408cba80> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd340828100> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36befb100> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36befa6c0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd3408c9f40> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36befa340> | Operating System |
| linux | linux_kernel | 6.13 | <built-in method update of dict object at 0x7fd342020300> | Operating System |
| Vulnerable | CPE |
|---|---|
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:* |