From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michael Welling <mwelling@ieee.org>
Subject: Re: [PATCH] net: phy: Handle postive return codes in phy_connect
Date: Sat, 5 Sep 2015 15:21:25 -0500
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Cc: Florian Fainelli <f.fainelli@gmail.com>, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
To: Andrew Lunn <andrew@lunn.ch>
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On Sat, Sep 05, 2015 at 09:47:55PM +0200, Andrew Lunn wrote:
> On Sat, Sep 05, 2015 at 02:44:01PM -0500, Michael Welling wrote:
> > On Sat, Sep 05, 2015 at 09:18:40PM +0200, Andrew Lunn wrote:
> > > On Sat, Sep 05, 2015 at 01:01:29PM -0500, Michael Welling wrote:
> > > > The function phy_connect_direct can possibly return a positive
> > > > return code. Using ERR_PTR with a positive value can lead to
> > > > deferencing of an invalid pointer.
> > > 
> > > Is this the correct fix? Would it not be better to find where the
> > > positive return code is from and fix that?
> > 
> > I guess I can trace it back to find out where the positive return code
> > is originating.
> > 
> > Is phy_connect_direct always supposed to return valid -errno?
> 
> I would look at this from a different angle. A positive ERRNO is
> probably a bug of some sort. So rather than papering over the cracks,
> go find what the real issue is.
> 
> It might not be an ERRNO. E.g. https://lkml.org/lkml/2015/9/3/534
> fixed a bug where a positive value is returned which is not an
> indication of an error.

It appears that I have stumbled upon the exact same issue as is fixed in
the patch above.

Good catch.
> 
> 	   Andrew