[Virtio-fs] [PATCH 4/5] fuse: For sending setattr in case of open(O_TRUNC)

[Vivek Goyal]

On Fri, Aug 21, 2020 at 05:05:16PM +0200, Miklos Szeredi wrote:
> On Fri, Jul 24, 2020 at 8:38 PM Vivek Goyal <vgoyal at redhat.com> wrote:
> >
> > open(O_TRUNC) will not kill suid/sgid on server and fuse_open_in does not
> > have information if caller has CAP_FSETID or not.
> >
> > So force sending setattr() which is called after open(O_TRUNC) so that
> > server clears setuid/setgid.
> 
> I don't really like the fact that we lose atomicity if
> handle_killpriv_v2 is enabled.
> 
> Let's just add a new flag to open as well.  If a filesystem doesn't
> want to add the complexity of handling that it can still just disable
> atomic_o_trunc.

Ok, will look into adding flag to open.

Vivek