Re: [PATCH v3] getrandom system call wrapper [BZ #17252]

[Florian Weimer <fweimer at redhat dot com>]

On 09/08/2016 03:54 PM, Andreas Schwab wrote:
> On Sep 08 2016, Florian Weimer <fweimer@redhat.com> wrote:
>
> > On 09/08/2016 03:36 PM, Andreas Schwab wrote:
> > > On Sep 08 2016, Florian Weimer <fweimer@redhat.com> wrote:
> > >
> > > > On 09/08/2016 03:19 PM, Andreas Schwab wrote:
> > > > > On Sep 08 2016, Florian Weimer <fweimer@redhat.com> wrote:
> > > > >
> > > > > > On 09/08/2016 03:01 PM, Andreas Schwab wrote:
> > > > > > > On Sep 08 2016, Florian Weimer <fweimer@redhat.com> wrote:
> > > > > > >
> > > > > > > > I have retained the __getrandom symbol mangling.  The justification for
> > > > > > > > that is that getrandom is a fairly common name.  Application code might
> > > > > > > > use it for something else entirely and interpose their definition, so that
> > > > > > > > libraries cannot rely on it doing the right thing.  I think the mangling
> > > > > > > > is justified because it is hard to spot that getrandom is broken due to
> > > > > > > > interposition.  As <sys/random.h> is a new header, the macro will be
> > > > > > > > exposed to few applications.
> > > > > > >
> > > > > > > It makes it impossible to take the address of the function, though.
> > > > > >
> > > > > > It does.  Do you have a better suggestion to achieve the same effect?
> > > > >
> > > > > If getrandom is ever standardized be POSIX this will have to be reverted
> > > > > anyway.
> > > >
> > > > So you don't object to this approach?
> > >
> > > Not providing a getrandom symbol is a bug.
> >
> > Is this better?
>
> You need to add the alias it to the stub, too.

Ahh, good catch.

How does this work?  Like this?

diff --git a/stdlib/getrandom.c b/stdlib/getrandom.c
index f0b3181..bb22dd8 100644
--- a/stdlib/getrandom.c
+++ b/stdlib/getrandom.c
@@ -29,3 +29,5 @@ __getrandom (void *buffer, size_t length, unsigned int 
flags)
 }

 stub_warning (__getrandom)
+
+weak_alias (__getrandom, getrand)

Thanks,
Florian