CVE-2024-56550

What it actually does

Incorrect control flow in arch_stack_walk_user_common on s390 architecture uses return instead of break after store_ip failure, omitting the pagefault_enable call and leaving page fault handling disabled for the process.

Why it matters to the business

Unexpected termination of user-space processes on s390 Linux systems, causing application instability and potential service outages with low overall urgency given minimal exploitability signals.

How an attack unfolds

This is a kernel stability bug with no attacker exploitation path; the condition arises during legitimate stack trace collection and leads to process death rather than code execution or privilege escalation.

How to fix it

Update the Linux kernel to a version containing commit 0c3836482481200ead7b416ca80c68a29cfdaabd or later on all s390 systems.

How to confirm the fix worked

Confirm the fix commit is present in the running kernel source tree or verify updated kernel packages are installed and reboot if required.

How to detect it

Review kernel and system logs on s390 hosts for entries indicating processes killed after unresolved page faults during stack trace operations.

What your security team should do

• Apply the referenced kernel commit on s390 systems promptly
• Monitor process termination logs for page-fault-related kills
• Prioritize s390 production workloads for patching