# CVE-2025-38359: s390/mm: Fix in_atomic() handling in do_secure_storage_access()

> A bug in the Linux kernel s390 architecture causes a kernel crash when handling secure storage access faults in atomic context.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Jul 2025
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-65759, BELL-CVE-2025-38359, DEBIAN-CVE-2025-38359, GHSA-62f3-xhhg-6p74, ROOT-OS-DEBIAN-11-CVE-2025-38359, ROOT-OS-DEBIAN-12-CVE-2025-38359, ROOT-OS-DEBIAN-13-CVE-2025-38359, ROOT-OS-UBUNTU-2204-CVE-2025-38359, ROOT-OS-UBUNTU-2404-CVE-2025-38359, UBUNTU-CVE-2025-38359

## What is CVE-2025-38359?

CVE-2025-38359 is a medium-severity denial of service vulnerability in Linux kernel, published on 25 Jul 2025. 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/mm: Fix in_atomic() handling in do_secure_storage_access()

Kernel user spaces accesses to not exported pages in atomic context
incorrectly try to resolve the page fault.
With debug options enabled call traces like this can be seen:

BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1523
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 419074, name: qemu-system-s39
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
INFO: lockdep is turned off.
Preemption disabled at:
[<00000383ea47cfa2>] copy_page_from_iter_atomic+0xa2/0x8a0
CPU: 12 UID: 0 PID: 419074 Comm: qemu-system-s39
Tainted: G        W           6.16.0-20250531.rc0.git0.69b3a602feac.63.fc42.s390x+debug #1 PREEMPT
Tainted: [W]=WARN
Hardware name: IBM 3931 A01 703 (LPAR)
Call Trace:
 [<00000383e990d282>] dump_stack_lvl+0xa2/0xe8
 [<00000383e99bf152>] __might_resched+0x292/0x2d0
 [<00000383eaa7c374>] down_read+0x34/0x2d0
 [<00000383e99432f8>] do_secure_storage_access+0x108/0x360
 [<00000383eaa724b0>] __do_pgm_check+0x130/0x220
 [<00000383eaa842e4>] pgm_check_handler+0x114/0x160
 [<00000383ea47d028>] copy_page_from_iter_atomic+0x128/0x8a0
([<00000383ea47d016>] copy_page_from_iter_atomic+0x116/0x8a0)
 [<00000383e9c45eae>] generic_perform_write+0x16e/0x310
 [<00000383e9eb87f4>] ext4_buffered_write_iter+0x84/0x160
 [<00000383e9da0de4>] vfs_write+0x1c4/0x460
 [<00000383e9da123c>] ksys_write+0x7c/0x100
 [<00000383eaa7284e>] __do_syscall+0x15e/0x280
 [<00000383eaa8417e>] system_call+0x6e/0x90
INFO: lockdep is turned off.

It is not allowed to take the mmap_lock while in atomic context. Therefore
handle such a secure storage access fault as if the accessed page is not
mapped: the uaccess function will return -EFAULT, and the caller has to
deal with this. Usually this means that the access is retried in process
context, which allows to resolve the page fault (or in this case export the
page).

Weakness: CWE-667 (Improper Locking)

## Which versions are affected by CVE-2025-38359?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-38359?

Apply the vendor's patch.

## Is CVE-2025-38359 being exploited?

There is no known exploitation of CVE-2025-38359 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-38359 and fix it if it is affected.

What it is: CVE-2025-38359 is a medium-severity denial of service vulnerability in Linux kernel, published on 25 Jul 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-38359 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-38359/ (Markdown: https://insights.sbomify.com/CVE-2025-38359/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38359
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38359
- OSV: https://osv.dev/vulnerability/CVE-2025-38359

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38359/
Summaries are generated and may contain mistakes; the official description above is the record.