CVE-2021-46993
CVE-2021-46993CVE-2021-46993
linux / linux_kernel
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.
Scoring
| CVSS | 7.8 () |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| Last modified | 2026-08-04 |