CVE-2023-53020 (GCVE-0-2023-53020)

Vulnerability from cvelistv5 – Published: 2025-03-27 16:43 – Updated: 2025-10-01 17:19
VLAI?
Title
l2tp: close all race conditions in l2tp_tunnel_register()
Summary
In the Linux kernel, the following vulnerability has been resolved: l2tp: close all race conditions in l2tp_tunnel_register() The code in l2tp_tunnel_register() is racy in several ways: 1. It modifies the tunnel socket _after_ publishing it. 2. It calls setup_udp_tunnel_sock() on an existing socket without locking. 3. It changes sock lock class on fly, which triggers many syzbot reports. This patch amends all of them by moving socket initialization code before publishing and under sock lock. As suggested by Jakub, the l2tp lockdep class is not necessary as we can just switch to bh_lock_sock_nested().
Severity ?
4.7 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 37159ef2c1ae1e696b24b260b241209a19f92c60 , < 2d77e5c0ad79004b5ef901895437e9cce6dfcc7e (git)
Affected: 37159ef2c1ae1e696b24b260b241209a19f92c60 , < 77e8ed776cdb1a24b2aab8fe7c6f1f154235e1ce (git)
Affected: 37159ef2c1ae1e696b24b260b241209a19f92c60 , < cef0845b6dcfa2f6c2c832e7f9622551456c741d (git)
Affected: 37159ef2c1ae1e696b24b260b241209a19f92c60 , < 0b2c59720e65885a394a017d0cf9cab118914682 (git)
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    Linux Linux Affected: 3.6
Unaffected: 0 , < 3.6 (semver)
Unaffected: 5.10.166 , ≤ 5.10.* (semver)
Unaffected: 5.15.91 , ≤ 5.15.* (semver)
Unaffected: 6.1.9 , ≤ 6.1.* (semver)
Unaffected: 6.2 , ≤ * (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.
  • 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.



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