CVE-2024-56550 s390/stacktrace: Use break instead of return statement

What is CVE-2024-56550?

CVE-2024-56550 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Dec 2024. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

s390/stacktrace: Use break instead of return statement

arch_stack_walk_user_common() contains a return statement instead of a break statement in case store_ip() fails while trying to store a callchain entry of a user space process. This may lead to a missing pagefault_enable() call.

If this happens any subsequent page fault of the process won't be resolved by the page fault handler and this in turn will lead to the process being killed.

Use a break instead of a return statement to fix this.

Which versions are affected by CVE-2024-56550?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2024-56550?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2024-56550 being exploited?

There is no known exploitation of CVE-2024-56550 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2024-56550, DEBIAN-CVE-2024-56550, GHSA-xv4r-xrmj-c649, UBUNTU-CVE-2024-56550.