Description
In the Linux kernel, the following vulnerability has been resolved: espintcp: remove encap socket caching to avoid reference leak The current scheme for caching the encap socket can lead to reference leaks when we try to delete the netns. The reference chain is: xfrm_state -> enacp_sk -> netns Since the encap socket is a userspace socket, it holds a reference on the netns. If we delete the espintcp state (through flush or individual delete) before removing the netns, the reference on the socket is dropped and the netns is correctly deleted. Otherwise, the netns may not be reachable anymore (if all processes within the ns have terminated), so we cannot delete the xfrm state to drop its reference on the socket. This patch results in a small (~2% in my tests) performance regression. A GC-type mechanism could be added for the socket cache, to clear references if the state hasn't been used "recently", but it's a lot more complex than just not caching the socket.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 to < e32bafd08ee35feacd47b05cc5bfe9cd9659cd25affectede27cca96cd68fa2c6814c90f9a1cfd36bb68c593 to < 9673ca00e6c5503069dc98780e2e89db0e663c16affectede27cca96cd68fa2c6814c90f9a1cfd36bb68c593 to < e4cde54b46a87231c77256a633be1bef62687d69affectede27cca96cd68fa2c6814c90f9a1cfd36bb68c593 to < b58a295d10065960bcb9d60cb8ca6ead9837cd27affectede27cca96cd68fa2c6814c90f9a1cfd36bb68c593 to < 9cbca30102028f9ad3d2098f935c4368f581fd07affectede27cca96cd68fa2c6814c90f9a1cfd36bb68c593 to < 74fd327767fb784c5875cf7c4ba1217f26020943affectede27cca96cd68fa2c6814c90f9a1cfd36bb68c593 to < 028363685bd0b7a19b4a820f82dd905b1dc83999affected
Linux Linux
Default version status: affected
5.6affected0 to < 5.6unaffected5.10.270 to ≤ 5.10.*unaffected5.15.221 to ≤ 5.15.*unaffected6.1.141 to ≤ 6.1.*unaffected6.6.93 to ≤ 6.6.*unaffected6.12.31 to ≤ 6.12.*unaffected6.14.9 to ≤ 6.14.*unaffected6.15 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/e32bafd08ee35feacd47b05cc5bfe9cd9659cd25 ↗
- https://git.kernel.org/stable/c/9673ca00e6c5503069dc98780e2e89db0e663c16 ↗
- https://git.kernel.org/stable/c/e4cde54b46a87231c77256a633be1bef62687d69 ↗
- https://git.kernel.org/stable/c/b58a295d10065960bcb9d60cb8ca6ead9837cd27 ↗
- https://git.kernel.org/stable/c/9cbca30102028f9ad3d2098f935c4368f581fd07 ↗
- https://git.kernel.org/stable/c/74fd327767fb784c5875cf7c4ba1217f26020943 ↗
- https://git.kernel.org/stable/c/028363685bd0b7a19b4a820f82dd905b1dc83999 ↗
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html ↗