tls: reject the combination of TLS and sockmap

Summary

In the Linux kernel, the following vulnerability has been resolved: tls: reject the combination of TLS and sockmap TLS and sockmap (BPF psock) integration hides a lot of latent bugs. Bugs which may be more or less relevant for real users but they are definitely exploitable. We could not find anyone actively using this integration so let's reject this config. Adding a TLS socket to a sockmap was already rejected by sk_psock_init() through the inet_csk_has_ulp() check. We need to reject the attempts to configure the TLS keys (rather than adding the ULP itself) because checking prior to the ULP installation is tricky without risking a race with sockmap getting added in parallel (sockmap does not hold the socket lock). This patch is a minimal rejection of the feature. Subsequent patch in the series will do a light dead code removal. Full cleanup would require a major rewrite of the Tx path, we don't need skmsg any more.

Timeline

1. Sep 24, 2026, 4:03 PM UTCCVE published
2. Oct 3, 2026, 10:57 AM UTCRecord last updated

Affected versions

• Linux Linux

  From d3b18ad31f93d0b6bae105c679018a1ba7daa9ca · fixed in c4896592744f30ff026f799947c5978bcfd7c8c7; From d3b18ad31f93d0b6bae105c679018a1ba7daa9ca · fixed in e26aa709454d48c3b3ef8d3100c8a04e7d9fd94e; From d3b18ad31f93d0b6bae105c679018a1ba7daa9ca · fixed in c3d4d537337f69e405a36fa561e7292ee4148bf7; From d3b18ad31f93d0b6bae105c679018a1ba7daa9ca · fixed in a08e780b6cc1153cbff8be55de9ec9da809e344f; From d3b18ad31f93d0b6bae105c679018a1ba7daa9ca · fixed in 460e6486617c17dd19abe8f3fc67d9a6fa25f8ca

• Linux Linux

  4.20

• KernelLinux

  From 4.20.0 · fixed in 6.1.189; From 6.2.0 · fixed in 6.6.158; From 6.7.0 · fixed in 6.12.111; From 6.13.0 · fixed in 6.18.53

References 5