CVE-2023-53461
Description
A flaw was identified in the Linux kernel’s io_uring subsystem related to how request completions are handled when an io_uring instance exits. During cleanup, the function io_ring_exit_work was waiting in an uninterruptible state for request completions. Under certain test and signal conditions (e.g., when the owning task is parked via SIGSTOP), this could block making progress on completions and trigger the kernel’s hung task detection mechanism, potentially leading to system instability or panic on systems configured with panic_on_hung_task.
Mitigation
To prevent a system panic, administrators can disable the `panic_on_hung_task` kernel parameter. This can be achieved by creating a new sysctl configuration file (e.g., `/etc/sysctl.d/99-disable-hung-task-panic.conf`) with the content `kernel.panic_on_hung_task = 0`. Apply the change using `sysctl -p /etc/sysctl.d/99-disable-hung-task-panic.conf`. This mitigation prevents system panics but does not prevent the hung task condition itself, which may still lead to system instability. A system reboot is required for the change to take full effect.
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).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU)
Inconsistent locking discipline can lead to deadlock.
Frequently Asked Questions
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