CVE-2021-47001 (GCVE-0-2021-47001)

Vulnerability from cvelistv5 – Published: 2024-02-28 08:13 – Updated: 2026-08-05 08:45
VLAI
Title
xprtrdma: Fix cwnd update ordering
Summary
In the Linux kernel, the following vulnerability has been resolved: xprtrdma: Fix cwnd update ordering After a reconnect, the reply handler is opening the cwnd (and thus enabling more RPC Calls to be sent) /before/ rpcrdma_post_recvs() can post enough Receive WRs to receive their replies. This causes an RNR and the new connection is lost immediately. The race is most clearly exposed when KASAN and disconnect injection are enabled. This slows down rpcrdma_rep_create() enough to allow the send side to post a bunch of RPC Calls before the Receive completion handler can invoke ib_post_recv().
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-03-05 16:58 UTC
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 2ae50ad68cd79224198b525f7bd645c9da98b6ff , < eddae8be7944096419c2ae29477a45f767d0fcd4 (git)
Affected: 2ae50ad68cd79224198b525f7bd645c9da98b6ff , < 8834ecb5df22b7ff3c9b0deba7726579bb613f95 (git)
Affected: 2ae50ad68cd79224198b525f7bd645c9da98b6ff , < 19b5fa9489b5706bc878c3a522a7f771079e2fa0 (git)
Affected: 2ae50ad68cd79224198b525f7bd645c9da98b6ff , < 35d8b10a25884050bb3b0149b62c3818ec59f77c (git)
Affected: 3791c5982ba1eebf2900ee7ca7b9a89619c26d54 (git)
Affected: 5.4.13 , < 5.5 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 5.5
Unaffected: 0 , < 5.5 (semver)
Unaffected: 5.10.38 , ≤ 5.10.* (semver)
Unaffected: 5.11.22 , ≤ 5.11.* (semver)
Unaffected: 5.12.5 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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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

Author Source Type Date Other

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.



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.