CVE-2023-52811: In the Linux kernel, the following vulnerability has been resolved: scsi: ibmvfc: Remove BUG_ON in the case of an empty event pool In practice the d...

Description

In the Linux kernel, the following vulnerability has been resolved: scsi: ibmvfc: Remove BUG_ON in the case of an empty event pool In practice the driver should never send more commands than are allocated to a queue's event pool. In the unlikely event that this happens, the code asserts a BUG_ON, and in the case that the kernel is not configured to crash on panic returns a junk event pointer from the empty event list causing things to spiral from there. This BUG_ON is a historical artifact of the ibmvfc driver first being upstreamed, and it is well known now that the use of BUG_ON is bad practice except in the most unrecoverable scenario. There is nothing about this scenario that prevents the driver from recovering and carrying on. Remove the BUG_ON in question from ibmvfc_get_event() and return a NULL pointer in the case of an empty event pool. Update all call sites to ibmvfc_get_event() to check for a NULL pointer and perfrom the appropriate failure or recovery action.

Metrics

CVSS 3.1

5.5/10

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

EPSS Probability

0.25%

16.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-476

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	< 5.15.140
Linux	Linux Kernel	>= 5.16, < 6.1.64
Linux	Linux Kernel	>= 6.2, < 6.5.13
Linux	Linux Kernel	>= 6.6, < 6.6.3

References

Timeline

Published: May 21, 2024
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2023-52811?

In the Linux kernel, the following vulnerability has been resolved: scsi: ibmvfc: Remove BUG_ON in the case of an empty event pool In practice the driver should never send more commands than are allocated to a queue's event pool. In the unlikely event that this happens, the code asserts a BUG_ON, and in the case that the kernel is not configured to crash on panic returns a junk event pointer from the empty event list causing things to spiral from there. This BUG_ON is a historical artifact of the ibmvfc driver first being upstreamed, and it is well known now that the use of BUG_ON is bad practice except in the most unrecoverable scenario. There is nothing about this scenario that prevents the driver from recovering and carrying on. Remove the BUG_ON in question from ibmvfc_get_event() and return a NULL pointer in the case of an empty event pool. Update all call sites to ibmvfc_get_event() to check for a NULL pointer and perfrom the appropriate failure or recovery action.

How severe is CVE-2023-52811?

CVE-2023-52811 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.25% probability of exploitation in the next 30 days.

How do I fix CVE-2023-52811?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.