CVE-2022-50676

Description

A potential deadlock vulnerability was found in the RDS (Reliable Datagram Sockets) TCP transport in the Linux kernel. In rds_tcp_reset_callbacks(), cancel_delayed_work_sync() is called while holding the socket lock (lock_sock()). However, the worker functions rds_send_xmit() and rds_recv_worker() may also try to acquire lock_sock(), creating a deadlock scenario. This can cause the system to hang.

Statement

This is a deadlock vulnerability in the RDS networking subsystem that can cause system hangs when RDS over TCP connections are reset. The vulnerability requires local access and the ability to use RDS sockets.

Mitigation

To mitigate this issue, prevent the rds_tcp module from being loaded. See https://access.redhat.com/solutions/41278 for instructions on how to blacklist a kernel module.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score4.7N/A7.5
Attack VectorLocalN/ANetwork
Attack ComplexityHighN/ALow
Privileges RequiredLowN/ANone
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/ANone
Integrity ImpactNoneN/ANone
Availability ImpactHighN/AHigh

Vector

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

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

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Other); DoS: Crash, Exit, or Restart

Each thread of execution will "hang" and prevent tasks from completing. In some cases, CPU consumption may occur if a lock check occurs in a tight loop.

Frequently Asked Questions

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