Messages in this thread | | | Subject | Re: [PATCH] net: renesas: fix a potential NULL pointer dereference | From | Sergei Shtylyov <> | Date | Mon, 11 Mar 2019 13:43:18 +0300 |
| |
Hello!
On 03/11/2019 10:43 AM, Geert Uytterhoeven wrote:
>> In case of_get_phy_mode fails, the fix returns NULL to avoid >> the NULL pointer dereference. >> >> Signed-off-by: Kangjie Lu <kjlu@umn.edu> > > Thanks for your patch! > >> --- a/drivers/net/ethernet/renesas/sh_eth.c >> +++ b/drivers/net/ethernet/renesas/sh_eth.c >> @@ -3187,6 +3187,8 @@ static struct sh_eth_plat_data *sh_eth_parse_dt(struct device *dev) >> return NULL; >> >> pdata->phy_interface = of_get_phy_mode(np); >> + if (unlikely(!pdata->phy_interface)) >> + return NULL; > > of_get_phy_mode() does not return a pointer, but a phy mode index. > Hence zero is a valid value. > > So I'm wondering where is the potential NULL pointer dereference?
Hm, not seeing NULL deref as well...
> Perhaps we do need to check for negative error codes? > Or is this already handled later, by {of_,}phy_connect()?
Not seeing such handling too... The v2 patch seems good though, as the "phy-mode" prop is mandatory anyway.
> Gr{oetje,eeting}s, > > Geert
MBR, Sergei
| |