CVE-2021-46940: linux kernel Integer Overflow — Fix

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.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-190 Integer Overflow

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.10.0 — 5.10.36
linux	linux_kernel	5.11.0 — 5.11.20
linux	linux_kernel	5.12.0 — 5.12.3

References

Advisories & Patches

https://git.kernel.org/stable/c/13a779de4175df602366d129e41782ad7168cef0 https://git.kernel.org/stable/c/337b1546cde87fb8588ddaedf0201b769baa572a https://git.kernel.org/stable/c/dbdf22fc825fdb1d97f23230064e0f9819471628 https://git.kernel.org/stable/c/ea6803ff2cd1a2d7d880256bf562172b708a76ff https://git.kernel.org/stable/c/13a779de4175df602366d129e41782ad7168cef0 https://git.kernel.org/stable/c/337b1546cde87fb8588ddaedf0201b769baa572a https://git.kernel.org/stable/c/dbdf22fc825fdb1d97f23230064e0f9819471628 https://git.kernel.org/stable/c/ea6803ff2cd1a2d7d880256bf562172b708a76ff

Frequently Asked Questions

What is CVE-2021-46940? +

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. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2021-46940? +

CVE-2021-46940 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2021-46940? +

CVE-2021-46940 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-46940? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2021-46940