PT-2024-36920 · Linux+1 · Linux Kernel+1
John Hubbard
·
Published
2024-11-20
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Updated
2025-09-29
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CVE-2024-56612
CVSS v3.1
5.5
Medium
| Vector | AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Name of the Vulnerable Software and Affected Versions
Linux kernel version 6.12
Description
A flaw in the Linux kernel's
unpin user pages() function assumes it handles NULL pages in the pages array, which is not the case. This issue can cause a kernel NULL pointer dereference. The problem arises when booting on x86 with specific configurations and running the tools/testing/selftests/mm/gup longterm test, resulting in a crash. The unpin user pages() function does not handle NULL pages, unlike unpin folios(). Technical details include the sanity check pinned pages() function and the check and migrate movable pages or folios() function.Recommendations
To resolve this issue, update the Linux kernel to a version that includes the fix for handling NULL pages in
unpin user pages(). As a temporary workaround, consider modifying the unpin user pages() function to skip NULL pages, similar to unpin folios().Exploit
Fix
NULL Pointer Dereference
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Weakness Enumeration
Related Identifiers
Affected Products
Alt Linux
Linux Kernel