# CVE-2022-49989: xen/privcmd: fix error exit of privcmd_ioctl_dm_op()

Status: published. Published: 2025-06-18. Updated: 2026-11-05.

In the Linux kernel, the following vulnerability has been resolved:

xen/privcmd: fix error exit of privcmd_ioctl_dm_op()

The error exit of privcmd_ioctl_dm_op() is calling unlock_pages()
potentially with pages being NULL, leading to a NULL dereference.

Additionally lock_pages() doesn't check for pin_user_pages_fast()
having been completely successful, resulting in potentially not
locking all pages into memory. This could result in sporadic failures
when using the related memory in user mode.

Fix all of that by calling unlock_pages() always with the real number
of pinned pages, which will be zero in case pages being NULL, and by
checking the number of pages pinned by pin_user_pages_fast() matching
the expected number of pages.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Linux / Linux: ≥ ab520be8cd5d56867fc95cfbc34b90880faf1f9d; < 6de50db104af0dc921f593fd95c55db86a52ceef (affected, git); ≥ ab520be8cd5d56867fc95cfbc34b90880faf1f9d; < c2b7bae7c90051fd6a679d5dee00400d67ebbf4a (affected, git); ≥ ab520be8cd5d56867fc95cfbc34b90880faf1f9d; < 45d47bd9b96e7874b98dbcc7602fe2826c5d62a6 (affected, git); ≥ ab520be8cd5d56867fc95cfbc34b90880faf1f9d; < c5deb27895e017a0267de0a20d140ad5fcc55a54 (affected, git). Source: CNA: Linux
- Linux / Linux: 4.11 (affected); ≥ 0; < 4.11 (unaffected, semver); ≥ 5.10.140; ≤ 5.10.* (unaffected, semver); ≥ 5.15.64; ≤ 5.15.* (unaffected, semver); ≥ 5.19.6; ≤ 5.19.* (unaffected, semver); ≥ 6.0; ≤ * (unaffected, original_commit_for_fix). Source: CNA: Linux

## Severity and prioritization

- CISA KEV: No listing in collected sources

- EPSS: 0.25% as of 2026-11-05; percentile 16.80%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: Not reported

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://git.kernel.org/stable/c/6de50db104af0dc921f593fd95c55db86a52ceef (CNA: Linux)

- https://git.kernel.org/stable/c/c2b7bae7c90051fd6a679d5dee00400d67ebbf4a (CNA: Linux)

- https://git.kernel.org/stable/c/45d47bd9b96e7874b98dbcc7602fe2826c5d62a6 (CNA: Linux)

- https://git.kernel.org/stable/c/c5deb27895e017a0267de0a20d140ad5fcc55a54 (CNA: Linux)

## Provenance

- CNA: Linux: https://www.cve.org/CVERecord?id=CVE-2022-49989; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2022-49989; retrieved 2026-11-05; source updated Not reported

Revision: 78bdfcea47850060327212acfcc9f519204f4fce279444dec549ae64fd1a6239

Canonical: https://y2.dev/cve/CVE-2022-49989

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.