Re: [PATCH V2] selinux: access sid under READ/WRITE_ONCE

[Edward Adam Davis]

On Tue, 11 Mar 2025 11:19:49 -0400, Stephen Smalley wrote:
> > Reported-by: syzbot+00c633585760c05507c3@xxxxxxxxxxxxxxxxxxxxxxxxx
> > Closes: https://syzkaller.appspot.com/bug?extid=00c633585760c05507c3
> > Signed-off-by: Edward Adam Davis <eadavis@xxxxxx>
> > ---
> > V1 -> V2: replace with READ_ONCE/WRITE_ONCE
> 
> Thanks for the patch. Did you audit all other users of sksec->sid to
> see if they too should be wrapped with READ_ONCE()/WRITE_ONCE() or are
> already safe?
This fix is only for the issues reported by syzbot+00c633585760c05507c3.
I have confirmed that there are many contexts related to "sksec->sid" (at
least 29). I am not familiar with selinux, and it is unnecessary to do
excessive fixes before syzbot reports other issues.

Maybe the subject of my patch is not appropriate, and it may be more
appropriate to adjust it to "selinux: fix data race in socket create and
receive skb".

BR,
Edward