CVE Vulnerabilities

CVE-2021-28951

Improper Locking

Published: Mar 20, 2021 | Modified: Nov 07, 2023
CVSS 3.x
5.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
4.9 MEDIUM
AV:L/AC:L/Au:N/C:N/I:N/A:C
RedHat/V2
RedHat/V3
Ubuntu

An issue was discovered in fs/io_uring.c in the Linux kernel through 5.11.8. It allows attackers to cause a denial of service (deadlock) because exit may be waiting to park a SQPOLL thread, but concurrently that SQPOLL thread is waiting for a signal to start, aka CID-3ebba796fa25.

Weakness

The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.

Affected Software

Name Vendor Start Version End Version
Linux_kernel Linux * 5.11.8 (including)

Extended Description

Locking is a type of synchronization behavior that ensures that multiple independently-operating processes or threads do not interfere with each other when accessing the same resource. All processes/threads are expected to follow the same steps for locking. If these steps are not followed precisely - or if no locking is done at all - then another process/thread could modify the shared resource in a way that is not visible or predictable to the original process. This can lead to data or memory corruption, denial of service, etc.

Potential Mitigations

References