Re: [PATCH][next] lkdtm: remove redundant initialization of ret

[Greg Kroah-Hartman]

On Fri, Jun 21, 2019 at 04:03:47PM +0200, Greg Kroah-Hartman wrote:
> On Fri, Jun 14, 2019 at 10:43:11AM +0100, Colin King wrote:
> > From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> > 
> > The variable ret is being initialized with the value -EINVAL however
> > this value is never read and ret is being re-assigned later on. Hence
> > the initialization is redundant and can be removed.
> > 
> > Addresses-Coverity: ("Unused value")
> > Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> > Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>
> > ---
> >  drivers/misc/lkdtm/core.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c
> > index bba093224813..92df35fdeab0 100644
> > --- a/drivers/misc/lkdtm/core.c
> > +++ b/drivers/misc/lkdtm/core.c
> > @@ -390,7 +390,7 @@ static int __init lkdtm_module_init(void)
> >  {
> >  	struct crashpoint *crashpoint = NULL;
> >  	const struct crashtype *crashtype = NULL;
> > -	int ret = -EINVAL;
> > +	int ret;
> >  	int i;
> >  
> >  	/* Neither or both of these need to be set */
> > -- 
> > 2.20.1
> > 
> 
> With this patch now applied, I get this build warning:
> drivers/misc/lkdtm/core.c: In function lkdtm_module_init:
> drivers/misc/lkdtm/core.c:467:9: warning: ret may be used uninitialized in this function [-Wmaybe-uninitialized]
>   return ret;
>          ^~~
> 
> So are you _sure_ it shouldn't be initialized?

In looking at the code in my tree, ret is used uninitialized with this
patch, so maybe coverity is wrong, or I don't have all of the needed
patches?

thanks,

greg k-h