PT-2024-8991 · Linux+3 · Linux Kernel+3

Petr Machata

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Published

2024-05-24

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Updated

2024-11-27

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CVE-2021-47555

CVSS v3.1

5.5

Medium

VectorAV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Name of the Vulnerable Software and Affected Versions: Linux kernel (affected versions not specified)
Description: The issue is related to a memory leak in the Linux kernel's VLAN component. When a dummy netdevice is removed, it can cause an underflow of the reference count for the real device, leading to a memory leak and an endless loop. This is because dev put(real dev) is called in vlan dev free() without a corresponding dev hold(real dev) in register vlan dev(). To fix this, dev hold(real dev) is moved to vlan dev init(), which is the callback for ndo init(), making dev hold() and dev put() symmetrical for the VLAN's real device.
Recommendations: At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Integer Underflow

Memory Leak

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Weakness Enumeration

Related Identifiers

BDU:2024-10673
CVE-2021-47555
OPENSUSE-SU-2024_2372-1
OPENSUSE-SU-2024_2394-1
SUSE-SU-2024:2008-1
SUSE-SU-2024:2019-1
SUSE-SU-2024:2190-1
SUSE-SU-2024:2372-1
SUSE-SU-2024:2385-1
SUSE-SU-2024:2394-1
SUSE-SU-2024:2495-1
SUSE-SU-2024:2939-1
SUSE-SU-2024_2495-1

Affected Products

Astra Linux
Linux Kernel
Red Os
Suse