medium CVSS 5.5

CVE-2023-52774·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: s390/dasd: protect device queue against concurrent access In dasd_profile_start() the amount of requests on the device queue are counted. The access to the device queue is unprotected against concurrent access. With a lot of parallel I/O, especially with alias devices enabled, the device queue can change while dasd_profile_start() is accessing the queue. In the worst case this leads to a kernel panic due to incorrect pointer accesses. Fix this by taking the device lock before accessing the queue and counting the requests. Additionally the check for a valid profile data pointer can be done earlier to avoid unnecessary locking in a hot path.

Severity
medium
Software
Kernel
Fixed in
6.6.4
Published
2024-05-21

Affected versions

From: 6.2

Until: 6.6.4

Fixed in: 6.6.4

How to fix this CVE

Update your Linux kernel to version 6.6.4 or later to resolve a race condition in the DASD (Direct Access Storage Device) profiling code that could cause kernel panics under heavy parallel I/O workloads. This vulnerability primarily affects s390 architecture systems with alias devices enabled. Ensure your system has access to the latest kernel updates from your distribution's stable repository.

sudo dnf update kernel kernel-core kernel-modules

Defensia detects this vulnerability

How to check if you are affected

  1. Check your current kernel version: uname -r — if it shows 6.2.x through 6.6.3, you are vulnerable
  2. Verify DASD devices are present on your system: lsblk | grep dasd or cat /proc/dasd/devices — if output is empty, DASD is not in use and risk is lower
  3. Search system logs for kernel panic indicators related to dasd_profile: sudo grep -i 'dasd.*panic\|kernel panic.*dasd' /var/log/kern.log /var/log/messages 2>/dev/null
  4. After patching, confirm the new kernel version: uname -r — should be 6.6.4 or later

FAQ

What is CVE-2023-52774?

This vulnerability is a race condition in the Linux kernel's DASD device profiling code where concurrent access to the device queue without proper locking can corrupt kernel memory and trigger panics, especially on s390 systems with high parallel I/O traffic.

Is CVE-2023-52774 being actively exploited?

No, this vulnerability is not listed in CISA's Known Exploited Vulnerabilities catalog and no public exploits are available. However, it can be triggered under specific conditions involving heavy parallel I/O workloads.

What versions of Kernel are affected by CVE-2023-52774?

Linux kernel versions 6.2 through 6.6.3 are vulnerable. The fix is included in kernel 6.6.4 and later stable releases.

How do I check if my server is vulnerable to CVE-2023-52774?

Run 'uname -r' and compare against the vulnerable range (6.2-6.6.3). If your kernel falls within this range and DASD devices are present (check with 'cat /proc/dasd/devices'), your system is vulnerable.

Does Defensia detect CVE-2023-52774?

Yes — Defensia's CVE advisory scanner compares installed kernel package versions against the NVD database. If a vulnerable kernel is detected on a monitored server, CVE-2023-52774 will appear in your dashboard with remediation steps and affected package details.

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References

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