| Message ID | 3fd6aa8b-2529-7ff5-3e19-05267101b2a4@web.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/imx: Adjustments for two functions | expand |
On Sat, Oct 12, 2019 at 4:07 AM Markus Elfring <Markus.Elfring@web.de> wrote: > > From: Markus Elfring <elfring@users.sourceforge.net> > Date: Sat, 12 Oct 2019 10:30:21 +0200 > > The return value from a call of the function “kmemdup” was not checked > in this function implementation. Thus add the corresponding error handling. > > Fixes: 19022aaae677dfa171a719e9d1ff04823ce65a65 ("staging: drm/imx: Add parallel display support") > Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> > --- > drivers/gpu/drm/imx/parallel-display.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/imx/parallel-display.c b/drivers/gpu/drm/imx/parallel-display.c > index 35518e5de356..39c4798f56b6 100644 > --- a/drivers/gpu/drm/imx/parallel-display.c > +++ b/drivers/gpu/drm/imx/parallel-display.c > @@ -210,8 +210,13 @@ static int imx_pd_bind(struct device *dev, struct device *master, void *data) > return -ENOMEM; > > edidp = of_get_property(np, "edid", &imxpd->edid_len); > - if (edidp) > + if (edidp) { > imxpd->edid = kmemdup(edidp, imxpd->edid_len, GFP_KERNEL); > + if (!imxpd->edid) { > + devm_kfree(dev, imxpd); You should not try to free imxpd here as it is a resource-managed allocation via devm_kzalloc(). It means memory allocated with this function is automatically freed on driver detach. So, this patch introduces a double-free. > + return -ENOMEM; > + } > + } > > ret = of_property_read_string(np, "interface-pix-fmt", &fmt); > if (!ret) { > -- > 2.23.0 >
On Sat, 12 Oct 2019, Navid Emamdoost wrote: > On Sat, Oct 12, 2019 at 4:07 AM Markus Elfring <Markus.Elfring@web.de> wrote: > > > > From: Markus Elfring <elfring@users.sourceforge.net> > > Date: Sat, 12 Oct 2019 10:30:21 +0200 > > > > The return value from a call of the function “kmemdup” was not checked > > in this function implementation. Thus add the corresponding error handling. > > > > Fixes: 19022aaae677dfa171a719e9d1ff04823ce65a65 ("staging: drm/imx: Add parallel display support") > > Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> > > --- > > drivers/gpu/drm/imx/parallel-display.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/imx/parallel-display.c b/drivers/gpu/drm/imx/parallel-display.c > > index 35518e5de356..39c4798f56b6 100644 > > --- a/drivers/gpu/drm/imx/parallel-display.c > > +++ b/drivers/gpu/drm/imx/parallel-display.c > > @@ -210,8 +210,13 @@ static int imx_pd_bind(struct device *dev, struct device *master, void *data) > > return -ENOMEM; > > > > edidp = of_get_property(np, "edid", &imxpd->edid_len); > > - if (edidp) > > + if (edidp) { > > imxpd->edid = kmemdup(edidp, imxpd->edid_len, GFP_KERNEL); > > + if (!imxpd->edid) { > > + devm_kfree(dev, imxpd); > > You should not try to free imxpd here as it is a resource-managed > allocation via devm_kzalloc(). It means memory allocated with this > function is > automatically freed on driver detach. So, this patch introduces a double-free. No, it's not double freed since the proposed code frees it with a devm function, removing it from the list of things to free later. One can wonder why the free has to be made apparent, though. julia > > > + return -ENOMEM; > > + } > > + } > > > > ret = of_property_read_string(np, "interface-pix-fmt", &fmt); > > if (!ret) { > > -- > > 2.23.0 > > > > > -- > Navid. >
diff --git a/drivers/gpu/drm/imx/parallel-display.c b/drivers/gpu/drm/imx/parallel-display.c index 35518e5de356..39c4798f56b6 100644 --- a/drivers/gpu/drm/imx/parallel-display.c +++ b/drivers/gpu/drm/imx/parallel-display.c @@ -210,8 +210,13 @@ static int imx_pd_bind(struct device *dev, struct device *master, void *data) return -ENOMEM; edidp = of_get_property(np, "edid", &imxpd->edid_len); - if (edidp) + if (edidp) { imxpd->edid = kmemdup(edidp, imxpd->edid_len, GFP_KERNEL); + if (!imxpd->edid) { + devm_kfree(dev, imxpd); + return -ENOMEM; + } + } ret = of_property_read_string(np, "interface-pix-fmt", &fmt); if (!ret) {