| Message ID | 20170707071135.GA29205@embeddedgus (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 07/07/2017 09:11 AM, Gustavo A. R. Silva wrote: > Check return value from call to of_match_device() > in order to prevent a NULL pointer dereference. > > In case of NULL print error message and return -ENODEV > > Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> > --- Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com> > drivers/net/ethernet/mediatek/mtk_eth_soc.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > index adaaafc..6a77dea 100644 > --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c > +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > @@ -2408,6 +2408,11 @@ static int mtk_probe(struct platform_device *pdev) > int i; > > match = of_match_device(of_mtk_match, &pdev->dev); > + if (!match) { > + dev_err(&pdev->dev, "failed to match device\n"); > + return -ENODEV; > + } > + > soc = (struct mtk_soc_data *)match->data; > > eth = devm_kzalloc(&pdev->dev, sizeof(*eth), GFP_KERNEL); >
On Fri, Jul 07, 2017 at 02:11:35AM -0500, Gustavo A. R. Silva wrote: > Check return value from call to of_match_device() > in order to prevent a NULL pointer dereference. > > In case of NULL print error message and return -ENODEV > > Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> > --- > drivers/net/ethernet/mediatek/mtk_eth_soc.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > index adaaafc..6a77dea 100644 > --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c > +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > @@ -2408,6 +2408,11 @@ static int mtk_probe(struct platform_device *pdev) > int i; > > match = of_match_device(of_mtk_match, &pdev->dev); > + if (!match) { > + dev_err(&pdev->dev, "failed to match device\n"); > + return -ENODEV; > + } > + > soc = (struct mtk_soc_data *)match->data; Hi Gustavo I think you are fixing the wrong thing. The soc variable is unused. Also, const struct of_device_id of_mtk_match[] = { { .compatible = "mediatek,mt2701-eth" }, {}, }; So match->data is NULL. This code is all pointless and should be removed, rather than try to avoid a NULL pointer dereference which can not actually happen. Andrew
Hi Andrew, Quoting Andrew Lunn <andrew@lunn.ch>: > On Fri, Jul 07, 2017 at 02:11:35AM -0500, Gustavo A. R. Silva wrote: >> Check return value from call to of_match_device() >> in order to prevent a NULL pointer dereference. >> >> In case of NULL print error message and return -ENODEV >> >> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> >> --- >> drivers/net/ethernet/mediatek/mtk_eth_soc.c | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c >> b/drivers/net/ethernet/mediatek/mtk_eth_soc.c >> index adaaafc..6a77dea 100644 >> --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c >> +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c >> @@ -2408,6 +2408,11 @@ static int mtk_probe(struct platform_device *pdev) >> int i; >> >> match = of_match_device(of_mtk_match, &pdev->dev); >> + if (!match) { >> + dev_err(&pdev->dev, "failed to match device\n"); >> + return -ENODEV; >> + } >> + >> soc = (struct mtk_soc_data *)match->data; > > Hi Gustavo > > I think you are fixing the wrong thing. The soc variable is unused. Also, > > const struct of_device_id of_mtk_match[] = { > { .compatible = "mediatek,mt2701-eth" }, > {}, > }; > > So match->data is NULL. This code is all pointless and should be > removed, rather than try to avoid a NULL pointer dereference which can > not actually happen. > You are right. Thank you for pointing it out. I'll remove that code and send a new patch shortly. Thanks! -- Gustavo A. R. Silva
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c index adaaafc..6a77dea 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c @@ -2408,6 +2408,11 @@ static int mtk_probe(struct platform_device *pdev) int i; match = of_match_device(of_mtk_match, &pdev->dev); + if (!match) { + dev_err(&pdev->dev, "failed to match device\n"); + return -ENODEV; + } + soc = (struct mtk_soc_data *)match->data; eth = devm_kzalloc(&pdev->dev, sizeof(*eth), GFP_KERNEL);
Check return value from call to of_match_device() in order to prevent a NULL pointer dereference. In case of NULL print error message and return -ENODEV Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> --- drivers/net/ethernet/mediatek/mtk_eth_soc.c | 5 +++++ 1 file changed, 5 insertions(+)