Subject: Re: [PATCH][next] net: phy: dp83869: fix unsigned comparisons against less than zero values

From: Dan Carpenter <[email-masked]>
Date: Tue, 6 Oct 2020 21:26:28 +0300

On Fri, Oct 02, 2020 at 12:26:49PM -0500, Dan Murphy wrote:
> Colin
> 
> On 10/2/20 11:54 AM, Colin King wrote:
> > From: Colin Ian King <[email-masked]>
> > 
> > Currently the comparisons of u16 integers value and sopass_val with
> > less than zero for error checking is always false because the values
> > are unsigned. Fix this by making these variables int.  This does not
> > affect the shift and mask operations performed on these variables
> > 
> > Addresses-Coverity: ("Unsigned compared against zero")
> > Fixes: 49fc23018ec6 ("net: phy: dp83869: support Wake on LAN")
> > Signed-off-by: Colin Ian King <[email-masked]>
> > ---
> >   drivers/net/phy/dp83869.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/phy/dp83869.c b/drivers/net/phy/dp83869.c
> > index 0aee5f645b71..cf6dec7b7d8e 100644
> > --- a/drivers/net/phy/dp83869.c
> > +++ b/drivers/net/phy/dp83869.c
> > @@ -305,7 +305,7 @@ static int dp83869_set_wol(struct phy_device *phydev,
> >   static void dp83869_get_wol(struct phy_device *phydev,
> >   			    struct ethtool_wolinfo *wol)
> >   {
> > -	u16 value, sopass_val;
> > +	int value, sopass_val;
> >   	wol->supported = (WAKE_UCAST | WAKE_BCAST | WAKE_MAGIC |
> >   			WAKE_MAGICSECURE);
> 
> Wonder why this was not reported before as the previous comparison issue
> reported by zero day.

It was reported on Sep 25.  I forward those zero day bot emails.

https://lore.kernel.org/lkml/20200925123858.GX18329@kadam/

regards,
dan carpenter