Hi Linus,

the attached patch fixes a flaw in the "parent process death signal"
when executing SUID binaries. An unprivileged user may send arbitrary
signal to a child process even if it is running with higher privileges.

The idea to fix this issue is to reset pdeath_signal not only on fork,
but also on the execution of a SUID binary.

Michael, if we fix it this way, then the prctl() manual page should
reflect that behavior.

>From comments it seems that we have to also reset pdeath_signal inside
LSM when it comes to capability-raised executes, but I must admit that I
got lost there.

Regards

Marcel