CVE-2021-47416

MEDIUM
Published May 21, 2024 Modified Dec 31, 2024 CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: phy: mdio: fix memory leak Syzbot reported memory leak in MDIO bus interface, the problem was in wrong state logic. MDIOBUS_ALLOCATED indicates 2 states: 1. Bus is only allocated 2. Bus allocated and __mdiobus_register() fails, but device_register() was called In case of device_register() has been called we should call put_device() to correctly free the memory allocated for this device, but mdiobus_free() calls just kfree(dev) in case of MDIOBUS_ALLOCATED state To avoid this behaviour we need to set bus->state to MDIOBUS_UNREGISTERED _before_ calling device_register(), because put_device() should be called even in case of device_register() failure.

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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-401 CWE-401

Affected Products

Vendor Product
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel

References

Advisories & Patches

https://git.kernel.org/stable/c/064c2616234a7394867c924b5c1303974f3a4f4d https://git.kernel.org/stable/c/0d2dd40a7be61b89a7c99dae8ee96389d27b413a https://git.kernel.org/stable/c/2250392d930bd0d989f24d355d6355b0150256e7 https://git.kernel.org/stable/c/2397b9e118721292429fea8807a698e71b94795f https://git.kernel.org/stable/c/25e9f88c7e3cc35f5e3d3db199660d28a15df639 https://git.kernel.org/stable/c/414bb4ead1362ef2c8592db723c017258f213988 https://git.kernel.org/stable/c/ca6e11c337daf7925ff8a2aac8e84490a8691905 https://git.kernel.org/stable/c/f4f502a04ee1e543825af78f47eb7785015cd9f6 https://git.kernel.org/stable/c/064c2616234a7394867c924b5c1303974f3a4f4d https://git.kernel.org/stable/c/0d2dd40a7be61b89a7c99dae8ee96389d27b413a https://git.kernel.org/stable/c/2250392d930bd0d989f24d355d6355b0150256e7 https://git.kernel.org/stable/c/2397b9e118721292429fea8807a698e71b94795f https://git.kernel.org/stable/c/25e9f88c7e3cc35f5e3d3db199660d28a15df639 https://git.kernel.org/stable/c/414bb4ead1362ef2c8592db723c017258f213988 https://git.kernel.org/stable/c/ca6e11c337daf7925ff8a2aac8e84490a8691905 https://git.kernel.org/stable/c/f4f502a04ee1e543825af78f47eb7785015cd9f6

Frequently Asked Questions

What is CVE-2021-47416? +
In the Linux kernel, the following vulnerability has been resolved: phy: mdio: fix memory leak Syzbot reported memory leak in MDIO bus interface, the problem was in wrong state logic. MDIOBUS_ALLOCATED indicates 2 states: 1. Bus is only allocated 2. Bus allocated and __mdiobus_register() fails, but device_register() was called In case of device_register() has been called we should call put_device() to correctly free the memory allocated for this device, but mdiobus_free() calls just kfree(dev) in case of MDIOBUS_ALLOCATED state To avoid this behaviour we need to set bus->state to MDIOBUS_UNREGISTERED _before_ calling device_register(), because put_device() should be called even in case of device_register() failure. It has a CVSS v3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2021-47416? +
CVE-2021-47416 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-2021-47416? +
CVE-2021-47416 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-2021-47416? +
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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