CVE-2025-21728 bpf: Send signals asynchronously if !preemptible

In the Linux kernel, the following vulnerability has been resolved: bpf: Send signals asynchronously if !preemptible BPF programs can execute in all kinds of contexts and when a program running in a non-preemptible context uses the bpfsendsignal kfunc, it will cause issues because this kfunc can...

kernel: possible to send arbitrary signals to a privileged (suidroot) parent process

A flaw was found in the Linux kernel loose validation of child/parent process identification handling while filtering signal handlers. A local attacker is able to abuse this flaw to bypass checks to send any signal to a privileged process...