Re: [PATCH 5.0 047/246] fs: Make splice() and tee() take into account O_NONBLOCK flag on pipes

[Sasha Levin]

On Thu, Apr 04, 2019 at 07:32:00PM +0200, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
> On Thu, Apr 04, 2019 at 04:16:57PM +0000, Slavomir Kaslev wrote:
> > On Thu, 2019-04-04 at 10:45 +0200, Greg Kroah-Hartman wrote:
> > > 5.0-stable review patch.  If anyone has any objections, please let me
> > > know.
> > >
> > > ------------------
> > >
> > > [ Upstream commit ee5e001196d1345b8fee25925ff5f1d67936081e ]
> > >
> > > The current implementation of splice() and tee() ignores O_NONBLOCK
> > > set
> > > on pipe file descriptors and checks only the SPLICE_F_NONBLOCK flag
> > > for
> > > blocking on pipe arguments.  This is inconsistent since splice()-ing
> > > from/to non-pipe file descriptors does take O_NONBLOCK into
> > > consideration.
> > >
> > > Fix this by promoting O_NONBLOCK, when set on a pipe, to
> > > SPLICE_F_NONBLOCK.
> >
> > [...]
> >
> > > This change does have potential of breaking users who don't expect
> > > EAGAIN from splice() when SPLICE_F_NONBLOCK is not set.  OTOH
> > > programs
> > > that set O_NONBLOCK and don't anticipate EAGAIN are arguably
> > > buggy[2].
> >
> > Hi Greg,
> >
> > Can you drop this one from the stable queues? We discussed it with
> > Sasha[1] already in the autosel patches thread.
> >
> > [1] https://lkml.org/lkml/2019/4/3/811
>
> Dropped from everywhere now.
>
> Sasha, how did this still get in?

Sorry about that, I dropped it from the wrong local branch :(

--
Thanks,
Sasha