In the Linux kernel, the following vulnerability has been resolved: apparmor: avoid per-cpu hold underflow in aa_get_buffer When aa_get_buffer() pulls from the per-cpu list it unconditionally decrements cache->hold. If hold reaches 0 while count is still non-zero, the unsigned decrement wraps to UINT_MAX. This keeps hold non-zero for a very long time, so aa_put_buffer() never returns buffers to the global list, which can starve other CPUs and force repeated kmalloc(aa_g_path_max) allocations.
In the Linux kernel, the following vulnerability has been resolved:
apparmor: avoid per-cpu hold underflow in aa_get_buffer
When aa_get_buffer() pulls from the per-cpu list it unconditionally decrements cache->hold. If hold reaches 0 while count is still non-zero, the unsigned decrement wraps to UINT_MAX. This keeps hold non-zero for a very long time, so aa_put_buffer() never returns buffers to the global list, which can starve other CPUs and force repeated kmalloc(aa_g_path_max) allocations.
Guard the decrement so hold never underflows.
为什么是这个 VPI(可解释·实验性)
VPI 计算依据
| 影响度 | 55.00 |
| 利用信号(无额外利用信号) | ×1.00 |
| VPI | 55.00 |
VPI 公式 vpi-v1