Messages in this thread | | | Date | Mon, 7 Jan 2013 23:28:57 -0500 | Subject | Re: [PATCH] backlight: check null deference of name when device is registered | From | "devendra.aaru" <> |
| |
On Mon, Jan 7, 2013 at 8:35 PM, Andrew Morton <akpm@linux-foundation.org> wrote: > On Tue, 08 Jan 2013 10:25:35 +0900 Jingoo Han <jg1.han@samsung.com> wrote: > >> On Tuesday, January 08, 2013 9:02 AM, Andrew Morton wrote >> > On Fri, 04 Jan 2013 17:29:11 +0900 >> > Jingoo Han <jg1.han@samsung.com> wrote: >> > >> > > NULL deference of name is checked when device is registered. >> > > If the name is null, it will cause a kernel oops in dev_set_name(). >> > > >> > > ... >> > > >> > > --- a/drivers/video/backlight/backlight.c >> > > +++ b/drivers/video/backlight/backlight.c >> > > @@ -292,6 +292,11 @@ struct backlight_device *backlight_device_register(const char *name, >> > > struct backlight_device *new_bd; >> > > int rc; >> > > >> > > + if (name == NULL) { >> > > + pr_err("backlight name is null\n"); >> > > + return ERR_PTR(-EINVAL); >> > > + } >> > > + >> > > pr_debug("backlight_device_register: name=%s\n", name); >> > >> > I don't understand this. >> > >> > Is there some driver which is calling these functions with name=NULL? >> > If so, which one(s)? >> >> No, there is no one. >> >> > >> > If "no" then why don't we declare that "passing name=NULL is a bug" and >> > leave the code as-is? >> >> Do you mean following? >> >> + if (name == NULL) >> + pr_err("passing name=NULL is a bug"); >> + >> pr_debug("backlight_device_register: name=%s\n", name); > > Nope; I'm suggesting we leave the code alone. If someone passes in > NULL they will get a nice oops and their bug will then get fixed. >
We still fail the probe in the patch Jingoo Han sent, anyways if i catch your point correctly is this the lines you wanted?
+ /** + * BUG if the name of the backlight device + * is a NULL + */ + BUG_ON(!name);
| |