arch_topology: Avoid use-after-free for scale_freq_data
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
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.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- Linux Linux
Version range not reported
- Linux Linux
5.13