In the Linux kernel, the following vulnerability has been resolved: ALSA: control: Validate buf_len before strnlen() in snd_ctl_elem_init_enum_names() snd_ctl_elem_init_enum_names() advances pointer p through the names buffer while decrementing buf_len. If buf_len reaches zero but items remain, the next iteration calls strnlen(p, 0). While strnlen(p, 0) returns 0 and would hit the existing name_len == 0 error path, CONFIG_FORTIFY_SOURCE's fortified strnlen() first checks maxlen against __buil
In the Linux kernel, the following vulnerability has been resolved:
ALSA: control: Validate buf_len before strnlen() in snd_ctl_elem_init_enum_names()
snd_ctl_elem_init_enum_names() advances pointer p through the names buffer while decrementing buf_len. If buf_len reaches zero but items remain, the next iteration calls strnlen(p, 0).
While strnlen(p, 0) returns 0 and would hit the existing name_len == 0 error path, CONFIG_FORTIFY_SOURCE's fortified strnlen() first checks maxlen against __builtin_dynamic_object_size(). When Clang loses track of p's object size inside the loop, this triggers a BRK exception panic before the return value is examined.
Add a buf_len == 0 guard at the loop entry to prevent calling fortified strnlen() on an exhausted buffer.
Found by kernel fuzz testing through Xiaomi Smartphone.
왜 이 VPI인가 (설명가능 · 실험적)
VPI 산정 기준
| 영향도 | 55.00 |
| 악용 신호(추가 악용신호 없음) | ×1.00 |
| VPI | 55.00 |
VPI 공식 vpi-v1 기준