scsi: ufs: core: Fix data race in CPU latency PM QoS request handling
In the Linux kernel, the following vulnerability has been resolved:
scsi: ufs: core: Fix data race in CPU latency PM QoS request handling
The cpu_latency_qos_add/remove/update_request interfaces lack internal
synchronization by design, requiring the caller to ensure thread safety.
The current implementation relies on the 'pm_qos_enabled' flag, which is
insufficient to prevent concurrent access and cannot serve as a proper
synchronization mechanism. This has led to data races and list
corruption issues.
A typical race condition call trace is:
[Thread A]
ufshcd_pm_qos_exit()
--> cpu_latency_qos_remove_request()
--> cpu_latency_qos_apply();
--> pm_qos_update_target()
--> plist_del <--(1) delete plist node
--> memset(req, 0, sizeof(*req));
--> hba->pm_qos_enabled = false;
[Thread B]
ufshcd_devfreq_target
--> ufshcd_devfreq_scale
--> ufshcd_scale_clks
--> ufshcd_pm_qos_update <--(2) pm_qos_enabled is true
--> cpu_latency_qos_update_request
--> pm_qos_update_target
--> plist_del <--(3) plist node use-after-free
Introduces a dedicated mutex to serialize PM QoS operations, preventing
data races and ensuring safe access to PM QoS resources, including sysfs
interface reads.
CVE 정보
EPSS
EPSS는 취약점이 악용될 가능성을 예측하는 점수 모델입니다.
EPSS 점수
EPSS 모델은 0과 1(0~100%) 사이의 확률 점수를 생성합니다. 점수가 높을수록 취약점이 악용될 가능성이 높습니다.
날짜
EPSS V0
EPSS V1
EPSS V2 (> 2022-02-04)
EPSS V3 (> 2025-03-07)
EPSS V4 (> 2025-03-17)
2025-11-12
–
–
–
–
0.02%
2025-11-18
–
–
–
–
0.02%
2025-11-21
–
–
–
–
0.02%
2025-11-22
–
–
–
–
0.02%
2025-11-29
–
–
–
–
0.02%
2025-12-14
–
–
–
–
0.03%
2026-02-22
–
–
–
–
0.03%
2026-03-01
–
–
–
–
0.03%
2026-03-08
–
–
–
–
0.03%
2026-03-15
–
–
–
–
0.04%
2026-04-05
–
–
–
–
0.04%
2026-04-12
–
–
–
–
0.02%
2026-04-26
–
–
–
–
0.03%
2026-05-10
–
–
–
–
0.03%
2026-06-14
–
–
–
–
0.03%
EPSS 백분위수
백분위수는 EPSS 점수에 따라 CVE의 순위를 매기는 데 사용됩니다. 예를 들어 EPSS 점수 기준 95번째 백분위수의 CVE는 다른 CVE의 95%보다 악용될 가능성이 높습니다.