CVE intelligence and bounded remediation
CVE-2024-45024 — In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix hugetlb vs
In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix hugetlb vs. core-mm PT locking We recently made GUP's common page table walking code to also walk hugetlb VMAs without most hugetlb special-casing, preparing for the future of having less hugetlb-specific page table walking code in the codebase. Turns out that we missed one page table locking detail: page table locking for hugetlb folios that are not mapped using a single PMD/PUD. Assume we have hugetlb folio that spans multiple PTEs (e.g., 64 KiB hugetlb folios on arm64 with 4 KiB base page size). GUP, as it walks the page tables, will perform a pte_offset_map_lock() to grab the PTE table lock. However, hugetlb that concurrently modifies these page tables would actually grab the mm->page_table_lock: with USE_SPLIT_PTE_PTLOCKS, the locks would differ. Something similar can happen right now with hugetlb folios that span multiple PMDs when USE_SPLIT_PMD_PTLOCKS. This issue can be reproduced [1], for example triggering: [ 3105.936100] ------------[ cut here ]------------ [ 3105.939323] WARNING: CPU: 31 PID: 2732 at mm/gup.c:142 try_grab_folio+0x11c/0x188 [ 3105.944634] Modules linked in: [...] [ 3105.…
- Severity
- Medium
- CVSS
- 5.5 (3.1)
- Published
- 2024-09-11
- CISA KEV
- Not currently listed
- Ecosystem
- linux/kernel
- Weaknesses
- CWE-667
Affected products
- linux / linux_kernel
- linux / linux_kernel / 6.11
Matched remediation archetype
Race condition, TOCTOU, and lifecycle synchronization
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Map concurrent actors, shared state, lock boundaries, signals, callbacks, retries, and check-then-use sequences in the affected path.
- Determine whether untrusted users can influence timing, object names, filesystem state, or repeated state transitions.
- Identify clustered and multi-process behavior that repository-local tests may not represent.
Remediate safely
- Make the sensitive state transition atomic or protect it with a consistently ordered synchronization primitive.
- Perform authorization and invariant checks on the same authoritative object and transaction used for the operation.
- Use unique private resources, safe ownership transfer, and idempotent operations; add deterministic concurrency regression tests.
Authoritative sources
Complete CVE record and remediation plan
The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.