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CVE-2026-74643 (GCVE-0-2026-74643)

Vulnerability from cvelistv5 – Published: 2026-08-22 15:32 – Updated: 2026-08-22 15:32
VLAI
Title
samples/damon/mtier: error out for zero quota goal target values
Summary
In the Linux kernel, the following vulnerability has been resolved: samples/damon/mtier: error out for zero quota goal target values Patch series "mm/damon: avoid division by zero from damos_quota_score()". DAMON_SAMPLE_MTIER and DAMON_LRU_SORT allow the user to trigger division by zero in damos_quota_score(). Avoid it by adding parameters validation checks. This patch (of 2): damos_quota_score() can trigger division by zero if the target_value is zero. DAMON_SAMPLE_MTIER lets users set the target_value via node0_mem_{used,free}_bp parameters. It doesn't guard zero value case, though. As a result, users can trigger division by zero. Fix the issue by returning an error when the user tries to start DAMON with zero node0_mem_{used,free}_bp parameter values. DAMON_SAMPLE_MTIER is just a sample module, but the consequence is quite bad. Also the zero node0_mem_free_bp parameter might look like a reasonable setup to some users. Hence, the issue might really happen in the real world. One reliable way to reproduce the issue is like below: # cd /sys/module/damon_sample_mtier/parameters # echo 4096 > node0_start_addr # echo 8192 > node0_end_addr # echo 8192 > node1_start_addr # echo 81920 > node1_end_addr # echo 0 > node0_mem_free_bp # echo Y > enabled # dmesg -w [...] [18792.235916] Oops: divide error: 0000 [#1] SMP NOPTI [...] [18792.242787] RIP: 0010:damos_quota_score+0x6f/0x480 [...] This issue was discovered [1] by Sashiko.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: c5e67d40a10234541e220750297304df79aaedd0 , < e16b8d640ec99b28bc827560edcf9706e610c3aa (git)
Affected: c5e67d40a10234541e220750297304df79aaedd0 , < 684f271210becd7b8c4088f06c442499e48a43a0 (git)
Affected: c5e67d40a10234541e220750297304df79aaedd0 , < a16fd3ad9d89b05475864da97327870464611736 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.17
Unaffected: 0 , < 6.17 (semver)
Unaffected: 6.18.45 , ≤ 6.18.* (semver)
Unaffected: 7.1.9 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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Show details on NVD website
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    "datePublished": "2026-08-22T15:32:21.140Z",
    "dateReserved": "2026-08-15T05:44:03.922Z",
    "dateUpdated": "2026-08-22T15:32:21.140Z",
    "state": "PUBLISHED"
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    "redhat_vex": {
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      "cve": "CVE-2026-74643",
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      "initial_release_date": "2026-08-22T00:00:00+00:00",
      "product_status:known_not_affected": "274",
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      "title": "kernel: samples/damon/mtier: error out for zero quota goal target values",
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      "cve": "CVE-2026-74643",
      "id": "CVE-2026-74643",
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      "title": "SUSE CVE CVE-2026-74643",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.