CVE-2021-46993

sched: Fix out-of-bound access in uclamp

Description

In the Linux kernel, the following vulnerability has been resolved: sched: Fix out-of-bound access in uclamp Util-clamp places tasks in different buckets based on their clamp values for performance reasons. However, the size of buckets is currently computed using a rounding division, which can lead to an off-by-one error in some configurations. For instance, with 20 buckets, the bucket size will be 1024/20=51. A task with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly, correct indexes are in range [0,19], hence leading to an out of bound memory access. Clamp the bucket id to fix the issue.

Category

7.1
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.12%
Affected: Linux Linux
Affected: Linux Linux
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-46993?
CVE-2021-46993 has been scored as a high severity vulnerability.
How to fix CVE-2021-46993?
To fix CVE-2021-46993, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-46993 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-46993 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-46993?
CVE-2021-46993 affects Linux Linux, Linux Linux.
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