LiveActive security incident?Get immediate response
CVE Record

CVE-2024-38543: lib/test_hmm.c: handle src_pfns and dst_pfns allocation failure

In the Linux kernel, the following vulnerability has been resolved: lib/test_hmm.c: handle src_pfns and dst_pfns allocation failure The kcalloc() in dmirror_device_evict_chunk() will return null if the physical memory has run out. As a result, if src_pfns or dst_pfns is dereferenced, the null pointer dereference bug will happen. Moreover, the device is going away. If the kcalloc() fails, the pages mapping a chunk could not be evicted. So add a __GFP_NOFAIL flag in kcalloc(). Finally, as there is no need to have physically contiguous memory, Switch kcalloc() to kvcalloc() in order to avoid failing allocations.

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

This Linux kernel issue is a reliability flaw: under physical memory pressure, allocation failure in test_hmm code can lead to a null pointer dereference. The public record does not provide CVSS, active exploitation evidence, or a remote attack path. Treat it as patch-tracking work for Linux assets, not an emergency absent vendor-specific impact.

Executive priority

Moderate operational priority unless a vendor advisory raises severity for your environment. Patch during normal Linux maintenance cycles, with faster action for custom or exposed kernel deployments where affected versions are confirmed.

Technical view

In lib/test_hmm.c, dmirror_device_evict_chunk() used kcalloc() for src_pfns and dst_pfns. If allocation returned NULL and the pointers were dereferenced, a null pointer dereference could occur. The resolution adds no-fail allocation behavior and switches to kvcalloc() because physically contiguous memory is unnecessary.

Likely exposure

Exposure is limited to Linux systems running affected kernel versions or unpatched downstream kernels. The bundle lists Linux as affected and provides stable kernel commits, but does not map distribution packages or runtime prerequisites.

Exploitation context

The source bundle does not indicate active exploitation, KEV listing, exploit availability, privilege requirements, or a remote vector. The described condition depends on allocation failure during device eviction behavior in test_hmm code.

Researcher notes

Evidence is incomplete for severity and exploitability. The available record supports a kernel null pointer dereference from allocation failure and identifies stable fix commits, but not attack preconditions, affected configurations beyond Linux versions, or distribution package status.

Mitigation direction

  • Update Linux kernels through vendor-supported channels when fixes are available.
  • Verify downstream distribution advisories for backported stable commits.
  • Prioritize systems using affected kernel lines listed in the CVE record.
  • Do not deploy custom kernels missing the referenced stable fixes.

Validation and detection

  • Inventory Linux kernel versions across production and development assets.
  • Compare installed kernels with the CVE record and distribution advisories.
  • Confirm patched source includes the kvcalloc allocation change.
  • Record whether vendor kernels backported the referenced stable commits.
Prepared
Confidence
medium
Sources
7

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2024-38543 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
3Timeline events
2ADP providers
6Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: partial

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CVECVE Program Container
CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxb2ef9f5a5cb37643ca5def3516c546457074b882, b2ef9f5a5cb37643ca5def3516c546457074b882, b2ef9f5a5cb37643ca5def3516c546457074b882, b2ef9f5a5cb37643ca5def3516c546457074b882, b2ef9f5a5cb37643ca5def3516c546457074b882unaffected
LinuxLinux5.8, 0, 6.1.93, 6.6.33, 6.8.12, 6.9.3, 6.10affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.