In the Linux kernel, the following vulnerability has been resolved: arch_topology: Avoid use-after-free for scale_freq_data Currently topology_scale_freq_tick() (which gets called from scheduler_tick()) may end up using a pointer to "struct scale_freq_data", which was previously cleared by topology_clear_scale_freq_source(), as there is no protection in place here. The users of topology_clear_scale_freq_source() though needs a guarantee that the previously cleared scale_freq_data isn't used anymore, so they can free the related resources. Since topology_scale_freq_tick() is called from scheduler tick, we don't want to add locking in there. Use the RCU update mechanism instead (which is already used by the scheduler's utilization update path) to guarantee race free updates here. synchronize_rcu() makes sure that all RCU critical sections that started before it is called, will finish before it returns. And so the callers of topology_clear_scale_freq_source() don't need to worry about their callback getting called anymore.
History

Tue, 05 Nov 2024 08:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-05-21T14:35:33.884Z

Updated: 2024-11-04T12:03:35.743Z

Reserved: 2024-05-21T14:28:16.974Z

Link: CVE-2021-47318

cve-icon Vulnrichment

Updated: 2024-08-04T05:32:08.653Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2024-05-21T15:15:19.080

Modified: 2024-05-21T16:54:26.047

Link: CVE-2021-47318

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-05-21T00:00:00Z

Links: CVE-2021-47318 - Bugzilla