CVE-2021-46940 tools/power turbostat: Fix offset overflow issue in index converting

What is CVE-2021-46940?

CVE-2021-46940 is a medium-severity vulnerability in Linux kernel, published on 27 Feb 2024. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

tools/power turbostat: Fix offset overflow issue in index converting

The idx_to_offset() function returns type int (32-bit signed), but MSR_PKG_ENERGY_STAT is u32 and would be interpreted as a negative number. The end result is that it hits the if (offset < 0) check in update_msr_sum() which prevents the timer callback from updating the stat in the background when long durations are used. The similar issue exists in offset_to_idx() and update_msr_sum(). Fix this issue by converting the 'int' to 'off_t' accordingly.

Weakness: CWE-190

Which versions are affected by CVE-2021-46940?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-46940?

Apply the vendor's patch.

Is CVE-2021-46940 being exploited?

There is no known exploitation of CVE-2021-46940 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2021-46940, GHSA-3whp-4394-49gc, UBUNTU-CVE-2021-46940.