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.
Metrics
Affected Vendors & Products
No advisories yet.
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Thu, 26 Dec 2024 20:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| Metrics |
cvssV3_1
|
cvssV3_1
|
Tue, 05 Nov 2024 08:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-05-04T07:08:34.975Z
Reserved: 2024-05-21T14:28:16.974Z
Link: CVE-2021-47318
Updated: 2024-08-04T05:32:08.653Z
Status : Analyzed
Published: 2024-05-21T15:15:19.080
Modified: 2024-12-26T19:51:01.310
Link: CVE-2021-47318
OpenCVE Enrichment
No data.