In the Linux kernel, the following vulnerability has been resolved: net: l2tp: do not propagate multicast notification errors The tunnel create, tunnel modify, session create, and session modify netlink handlers send multicast notifications through helpers that can fail while allocating or encoding a message, or while multicasting it. For tunnel and session create/modify, a notification is sent after the live operation has completed. Returning a best-effort notification error as the command result can therefore report failure for an operation that already committed and can cause callers to retry and accumulate live objects. Keep sending notifications for listener visibility, but do not propagate their best-effort status as the command result. This also keeps the tunnel modify command consistent with the other notification-only paths.
https://git.kernel.org/stable/c/af20e269f7459d2ce69887fdf2fad7caf986c865
https://git.kernel.org/stable/c/9c340473f4822bb31b151c19afd17448eda5acd1
https://git.kernel.org/stable/c/50c4038f1670bf9a80c6a58ae83d1602decd8481
https://git.kernel.org/stable/c/0fe037d5eaad938aa3e9143ee071aa237750b42b