irrelevant locking

[Mateusz Guzik]

On Sun, Jan 17, 2016 at 11:05:15AM +0300, Chagin Dmitry wrote:
> On Sun, Jan 17, 2016 at 05:43:15AM +0200, Konstantin Belousov wrote:
> > On Sat, Jan 16, 2016 at 11:43:13PM +0100, Mateusz Guzik wrote:
> > > The real question is if it would make sense to add the bit to elf aux
> > > vector to save the call as done by the loader.
> > I once did a pass to remove (most of) sysctls executed during process
> > startup.  issetugid indeed may be treated same.
> 
> like a Linux AT_SECURE? our P_SUGID bit can be changed after exec,
> so the result of issetugid() implementated on auxv table will be unnafected
> by calls to setuid(), setgid() or other such calls.
> 

This is only to save issetugid call done early by the loader and it is
perfectly safe at that point.

This definitely is not a replacement for the syscall in general.

-- 
Mateusz Guzik <mjguzik gmail.com>