[PATCH] powerpc: signedness bug in update_flash_db()

[Dan Carpenter]

On Mon, Oct 01, 2018 at 10:02:54PM +0300, Dan Carpenter wrote:
> On Mon, Oct 01, 2018 at 08:22:01PM +0200, christophe leroy wrote:
> > 
> > 
> > Le 01/10/2018 à 18:44, Dan Carpenter a écrit :
> > > The "count < sizeof(struct os_area_db)" comparison is type promoted to
> > > size_t so negative values of "count" are treated as very high values and
> > > we accidentally return success instead of a negative error code.
> > > 
> > > This doesn't really change runtime much but it fixes a static checker
> > > warning.
> > > 
> > > Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>
> > > 
> > > diff --git a/arch/powerpc/platforms/ps3/os-area.c b/arch/powerpc/platforms/ps3/os-area.c
> > > index cdbfc5cfd6f3..f5387ad82279 100644
> > > --- a/arch/powerpc/platforms/ps3/os-area.c
> > > +++ b/arch/powerpc/platforms/ps3/os-area.c
> > > @@ -664,7 +664,7 @@ static int update_flash_db(void)
> > >   	db_set_64(db, &os_area_db_id_rtc_diff, saved_params.rtc_diff);
> > >   	count = os_area_flash_write(db, sizeof(struct os_area_db), pos);
> > > -	if (count < sizeof(struct os_area_db)) {
> > > +	if (count < 0 || count < sizeof(struct os_area_db)) {
> > 
> > Why not simply add a cast ? :
> > 
> > if (count < (ssize_t)sizeof(struct os_area_db)) {
> > 
> 
> There are so many ways to solve these and no accounting for taste.  Do
> you need me to resend or can you redo it yourself?
> 

Btw, I just went on vacation, and I'm not going to be back until next
week.

regards,
dan carpenter