CVE-2024-41027: Fix userfaultfd_api to return EINVAL as expected

Severity: low (CVSS 3.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-07-29 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: Fix userfaultfd_api to return EINVAL as expected Currently if we request a feature that is not set in the Kernel config we fail silently and return all the available features. However, the man page indicates we should return an EINVAL. We need to fix this issue since we can end up with a Kernel warning should a program request the feature UFFD_FEATURE_WP_UNPOPULATED on a kernel with the config not set with this feature. [ 200.812896] WARNING: CPU: 91 PID: 13634 at mm/memory.c:1660 zap_pte_range+0x43d/0x660 [ 200.820738] Modules linked in: [ 200.869387] CPU: 91 PID: 13634 Comm: userfaultfd Kdump: loaded Not tainted 6.9.0-rc5+ #8 [ 200.877477] Hardware name: Dell Inc. PowerEdge R6525/0N7YGH, BIOS 2.7.3 03/30/2022 [ 200.885052] RIP: 0010:zap_pte_range+0x43d/0x660

Affected products

Linux kernel: from 5.7 before 5.15.163; from 5.16 before 6.1.100; from 6.2 before 6.6.41; from 6.7 before 6.9.10; 6.10-rc1, 6.10-rc2, 6.10-rc3, 6.10-rc4, 6.10-rc5, 6.10-rc6 (+1) — fixed in 5.15.163, 6.1.100, 6.6.41, 6.9.10

How to fix

Upgrade to a fixed version: Linux kernel 5.15.163, 6.1.100, 6.6.41, 6.9.10. Check the vendor advisory for mitigations.

References

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