mptcp: fix race in mptcp_pm_nl_flush_addrs_doit()
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix race in mptcp_pm_nl_flush_addrs_doit() syzbot and Eulgyu Kim reported crashes in mptcp_pm_nl_get_local_id() and/or mptcp_pm_nl_is_backup() Root cause is list_splice_init() in mptcp_pm_nl_flush_addrs_doit() which is not RCU ready. list_splice_init_rcu() can not be called here while holding pernet->lock spinlock. Many thanks to Eulgyu Kim for providing a repro and testing our patches.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix race in mptcp_pm_nl_flush_addrs_doit() syzbot and Eulgyu Kim reported crashes in mptcp_pm_nl_get_local_id() and/or mptcp_pm_nl_is_backup() Root cause is list_splice_init() in mptcp_pm_nl_flush_addrs_doit() which is not RCU ready. list_splice_init_rcu() can not be called here while holding pernet->lock spinlock. Many thanks to Eulgyu Kim for providing a repro and testing our patches.
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/1f1b9523527df02685dde603f20ff6e603d8e4a1
- https://git.kernel.org/stable/c/338d40bab283da2639780ee3e458fb61f1567d8c
- https://git.kernel.org/stable/c/455e882192c9833f176f3fbbbb2f036b6c5bf555
- https://git.kernel.org/stable/c/51223bdd0f60b06cfc7f25885c4d4be917adba94
- https://git.kernel.org/stable/c/7896dbe990d56d5bb8097863b2645355633665eb
- https://git.kernel.org/stable/c/e2a9eeb69f7d4ca4cf4c70463af77664fdb6ab1d
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23169.json
- https://nvd.nist.gov/vuln/detail/CVE-2026-23169