On Mon, 12 Nov 2018 11:33:40 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
> On 09/11/2018 03:39, Eric Farman wrote:
> > Direct returns from within a loop are rude, but it doesn't mean it gets
> > to avoid releasing the memory acquired beforehand.
> >
> > Signed-off-by: Eric Farman <farman@xxxxxxxxxxxxx>
> > ---
> > drivers/s390/cio/vfio_ccw_cp.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c
> > index ef5ab45d94b3..70a006ba4d05 100644
> > --- a/drivers/s390/cio/vfio_ccw_cp.c
> > +++ b/drivers/s390/cio/vfio_ccw_cp.c
> > @@ -387,8 +387,10 @@ static int ccwchain_calc_length(u64 iova, struct channel_program *cp)
> > * orb specified one of the unsupported formats, we defer
> > * checking for IDAWs in unsupported formats to here.
> > */
> > - if ((!cp->orb.cmd.c64 || cp->orb.cmd.i2k) && ccw_is_idal(ccw))
> > + if ((!cp->orb.cmd.c64 || cp->orb.cmd.i2k) && ccw_is_idal(ccw)) {
> > + kfree(p);
> > return -EOPNOTSUPP;
> > + }
> >
> > if ((!ccw_is_chain(ccw)) && (!ccw_is_tic(ccw)))
> > break;
> >
>
> Clearly a bug.
>
> Reviewed-by: Pierre Morel<pmorel@xxxxxxxxxxxxx>
>
>
> I hate this function, I think we really should find a way to avoid these
> multiple alloc/copy/free of the ccw chain.
>
Yeah, that is a bit annoying. Maybe pre-alloc a per-device buffer for
it?
