CVE-2021-47132 (GCVE-0-2021-47132)

Vulnerability from cvelistv5 – Published: 2024-03-15 20:14 – Updated: 2026-05-23 15:19
VLAI
Title
mptcp: fix sk_forward_memory corruption on retransmission
Summary
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix sk_forward_memory corruption on retransmission MPTCP sk_forward_memory handling is a bit special, as such field is protected by the msk socket spin_lock, instead of the plain socket lock. Currently we have a code path updating such field without handling the relevant lock: __mptcp_retrans() -> __mptcp_clean_una_wakeup() Several helpers in __mptcp_clean_una_wakeup() will update sk_forward_alloc, possibly causing such field corruption, as reported by Matthieu. Address the issue providing and using a new variant of blamed function which explicitly acquires the msk spin lock.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 64b9cea7a0afe579dd2682f1f1c04f2e4e72fd25 , < b9c78b1a95966a7bd2ddae05b73eafc0cda4fba3 (git)
Affected: 64b9cea7a0afe579dd2682f1f1c04f2e4e72fd25 , < b5941f066b4ca331db225a976dae1d6ca8cf0ae3 (git)
Affected: 96db8ffef07516a6d7414b6988f2a4298a839977 (git)
Affected: 5.11.4 , < 5.12 (semver)
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Linux Linux Affected: 5.12
Unaffected: 0 , < 5.12 (semver)
Unaffected: 5.12.10 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
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  • 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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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