CVE-2021-46916: linux kernel Null Dereference — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: ixgbe: Fix NULL pointer dereference in ethtool loopback test The ixgbe driver currently generates a NULL pointer dereference when performing the ethtool loopback test. This is due to the fact that there isn't a q_vector associated with the test ring when it is setup as interrupts are not normally added to the test rings. To address this I have added code that will check for a q_vector before returning a napi_id value. If a q_vector is not present it will return a value of 0.

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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-476 CWE-476

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.11.0 — 5.11.16

References

Advisories & Patches

https://git.kernel.org/stable/c/31166efb1cee348eb6314e9c0095d84cbeb66b9d https://git.kernel.org/stable/c/758d19098df4b0bbca9f40d6ae6c82c9c18b9bba https://git.kernel.org/stable/c/31166efb1cee348eb6314e9c0095d84cbeb66b9d https://git.kernel.org/stable/c/758d19098df4b0bbca9f40d6ae6c82c9c18b9bba

Frequently Asked Questions

What is CVE-2021-46916? +

In the Linux kernel, the following vulnerability has been resolved: ixgbe: Fix NULL pointer dereference in ethtool loopback test The ixgbe driver currently generates a NULL pointer dereference when performing the ethtool loopback test. This is due to the fact that there isn't a q_vector associated with the test ring when it is setup as interrupts are not normally added to the test rings. To address this I have added code that will check for a q_vector before returning a napi_id value. If a q_vector is not present it will return a value of 0. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2021-46916? +

CVE-2021-46916 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-2021-46916? +

CVE-2021-46916 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-2021-46916? +

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-2021-46916