CVE-2025-13350 for Ubuntu Linux kernel

[Seth Arnold <seth.arnold () canonical com>]

Hello, today the Ubuntu Security Team published CVE-2025-13350 for the
Ubuntu packaging of the Linux kernel. The issue comes from an incorrectly
backported patch that caused us to mix an old-style with a new-style
garbage collector for Unix Domain Sockets.

Upstream kernels weren't affected because they did not cherry-pick pieces
of the transition.

I thought it worth sending a message to a widely read and widely archived
place to give everyone peace of mind: If you consume the upstream kernel
directly, you're fine. This issue only affected Ubuntu and anyone that
rebuilds Ubuntu kernels.

Thanks