In the Linux kernel, the following vulnerability has been resolved: md/md-bitmap: Synchronize bitmap_get_stats() with bitmap lifetime After commit ec6bb299c7c3 ("md/md-bitmap: add 'sync_size' into struct md_bitmap_stats"), following panic is reported: Oops: general protection fault, probably for non-canonical address RIP: 0010:bitmap_get_stats+0x2b/0xa0 Call Trace: <TASK> md_seq_show+0x2d2/0x5b0 seq_read_iter+0x2b9/0x470 seq_read+0x12f/0x180 proc_reg_read+0x57/0xb0 vfs_read+0xf6/0x380 ksys_read+0x6c/0xf0 do_syscall_64+0x82/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e Root cause is that bitmap_get_stats() can be called at anytime if mddev is still there, even if bitmap is destroyed, or not fully initialized. Deferenceing bitmap in this case can crash the kernel. Meanwhile, the above commit start to deferencing bitmap->storage, make the problem easier to trigger. Fix the problem by protecting bitmap_get_stats() with bitmap_info.mutex.
En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: md/md-bitmap: sincronizar bitmap_get_stats() con el tiempo de vida del mapa de bits Después de el commit ec6bb299c7c3 ("md/md-bitmap: agregar 'sync_size' en la estructura md_bitmap_stats"), se informa el siguiente pánico: Vaya: error de protección general, probablemente para una dirección no canónica RIP: 0010:bitmap_get_stats+0x2b/0xa0 Seguimiento de llamadas: md_seq_show+0x2d2/0x5b0 seq_read_iter+0x2b9/0x470 seq_read+0x12f/0x180 proc_reg_read+0x57/0xb0 vfs_read+0xf6/0x380 ksys_read+0x6c/0xf0 La causa principal es que bitmap_get_stats() se puede llamar en cualquier momento si mddev aún está allí, incluso si bitmap se destruye o no se inicializa por completo. La deferenciación de bitmap en este caso puede hacer que el kernel se bloquee. Mientras tanto, el commit anterior comienza a deferenciar bitmap->storage, lo que hace que el problema sea más fácil de desencadenar. Solucione el problema protegiendo bitmap_get_stats() con bitmap_info.mutex.
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 0x702bdd6aeb80> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x702bdd6ad0c0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x702bdd6a4b80> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x702bdd6ae080> | 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:*:*:*:*:*:*:*:* |