On Wed, 29 Jul 2009, Zhang Rui wrote: > On Tue, 2009-07-28 at 23:56 +0800, Julia Lawall wrote: > > From: Julia Lawall <julia@xxxxxxx> > > > > backlight_device_register may return an ERR_PTR value rather than a valid > > pointer. > > > > A simplified version of the semantic match that finds this problem is as > > follows: (http://coccinelle.lip6.fr/) > > > Signed-off-by: Julia Lawall <julia@xxxxxxx> > > > > --- > > drivers/acpi/video.c | 2 ++ > > 1 files changed, 2 insertions(+), 0 deletions(-) > > > > diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c > > index 8851315..29788db 100644 > > --- a/drivers/acpi/video.c > > +++ b/drivers/acpi/video.c > > @@ -982,6 +982,8 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device) > > sprintf(name, "acpi_video%d", count++); > > device->backlight = backlight_device_register(name, > > NULL, device, &acpi_backlight_ops); > > + if (IS_ERR(device->backlight)) > > + return; > > we should kfree(name) here. Yes, good point. thanks, julia > > device->backlight->props.max_brightness = device->brightness->count-3; > > kfree(name); > > how about this one? > > ÿÿbacklight_device_register may return an ERR_PTR value rather than a valid > pointer. > > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> > --- > drivers/acpi/video.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > Index: linux-2.6/drivers/acpi/video.c > =================================================================== > --- linux-2.6.orig/drivers/acpi/video.c > +++ linux-2.6/drivers/acpi/video.c > @@ -982,8 +982,10 @@ static void acpi_video_device_find_cap(s > sprintf(name, "acpi_video%d", count++); > device->backlight = backlight_device_register(name, > NULL, device, &acpi_backlight_ops); > - device->backlight->props.max_brightness = device->brightness->count-3; > kfree(name); > + if (IS_ERR(device->backlight)) > + return; > + device->backlight->props.max_brightness = device->brightness->count-3; > > result = sysfs_create_link(&device->backlight->dev.kobj, > &device->dev->dev.kobj, "device"); > > > > > >
