CVE-2022-49697
bpf: Fix request_sock leak in sk lookup helpers
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix request_sock leak in sk lookup helpers A customer reported a request_socket leak in a Calico cloud environment. We found that a BPF program was doing a socket lookup with takes a refcnt on the socket and that it was finding the request_socket but returning the parent LISTEN socket via sk_to_full_sk() without decrementing the child request socket 1st, resulting in request_sock slab object leak. This patch retains the existing behaviour of returning full socks to the caller but it also decrements the child request_socket if one is present before doing so to prevent the leak. Thanks to Curtis Taylor for all the help in diagnosing and testing this. And thanks to Antoine Tenart for the reproducer and patch input. v2 of this patch contains, refactor as per Daniel Borkmann's suggestions to validate RCU flags on the listen socket so that it balances with bpf_sk_release() and update comments as per Martin KaFai Lau's suggestion. One small change to Daniels suggestion, put "sk = sk2" under "if (sk2 != sk)" to avoid an extra instruction.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.27% · top 80% of all CVEs (6 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Weakness
Affected products
- affected edbf8c01de5a104a71ed6df2bf6421ceb2836a8e – < 8ffe2e50e9678c8373027492035f094b130437f1
- affected edbf8c01de5a104a71ed6df2bf6421ceb2836a8e – < 516760f1d2979903eaad5b437256913c5cd98416
- affected edbf8c01de5a104a71ed6df2bf6421ceb2836a8e – < b03607437ea81b850599f705096b05b85e7a4a71
- affected edbf8c01de5a104a71ed6df2bf6421ceb2836a8e – < 5a62b5ba4c0ce8315b6382cd4ace81b48cd121cd
- affected edbf8c01de5a104a71ed6df2bf6421ceb2836a8e – < 3046a827316c0e55fc563b4fb78c93b9ca5c7c37
- affected 5.2
- unaffected < 5.2
- unaffected 5.4.202 – ≤ 5.4.*
- unaffected 5.10.127 – ≤ 5.10.*
- unaffected 5.15.51 – ≤ 5.15.*
- unaffected 5.18.8 – ≤ 5.18.*
- unaffected 5.19 – ≤ *
References (5)
- https://git.kernel.org/stable/c/8ffe2e50e9678c8373027492035f094b130437f1 (opens in a new tab)
- https://git.kernel.org/stable/c/516760f1d2979903eaad5b437256913c5cd98416 (opens in a new tab)
- https://git.kernel.org/stable/c/b03607437ea81b850599f705096b05b85e7a4a71 (opens in a new tab)
- https://git.kernel.org/stable/c/5a62b5ba4c0ce8315b6382cd4ace81b48cd121cd (opens in a new tab)
- https://git.kernel.org/stable/c/3046a827316c0e55fc563b4fb78c93b9ca5c7c37 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2022-49697)Record last updated .