In the Linux kernel, the following vulnerability has been resolved: bpf: avoid holding freeze_mutex during mmap operation We use map->freeze_mutex to prevent races between map_freeze() and memory mapping BPF map contents with writable permissions. The way we naively do this means we'll hold freeze_mutex for entire duration of all the mm and VMA manipulations, which is completely unnecessary. This can potentially also lead to deadlocks, as reported by syzbot in [0]. So, instead, hold freeze_mutex only during writeability checks, bump (proactively) "write active" count for the map, unlock the mutex and proceed with mmap logic. And only if something went wrong during mmap logic, then undo that "write active" counter increment. [0] https://lore.kernel.org/bpf/[email protected]/
En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: bpf: evitar mantener freeze_mutex durante la operación mmap. Usamos map->freeze_mutex para evitar ejecuciones entre map_freeze() y el mapeo de memoria del contenido del mapa BPF con permisos de escritura. Esta forma ingenua de hacerlo implica mantener freeze_mutex durante todas las manipulaciones mm y VMA, lo cual es completamente innecesario. Esto también puede provocar interbloqueos, como informa syzbot en [0]. Por lo tanto, se mantiene freeze_mutex solo durante las comprobaciones de escritura, se aumenta (proactivamente) el contador de "escritura activa" del mapa, se desbloquea el mutex y se continúa con la lógica mmap. Solo si algo falla durante la lógica mmap, se deshace el incremento del contador de "escritura activa". [0] https://lore.kernel.org/bpf/[email protected]/
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 0x702bde244f80> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x702bdc0d1cc0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x702bdc0d3680> | Operating System |
| linux | linux_kernel | 6.14 | <built-in method update of dict object at 0x702bdc0d0dc0> | Operating System |
| linux | linux_kernel | 6.14 | <built-in method update of dict object at 0x702bfc1301c0> | Operating System |
| linux | linux_kernel | 6.14 | <built-in method update of dict object at 0x702bdd1281c0> | 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:6.14:rc1:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* |