Hello,
On Thu, Apr 19, 2018 at 08:01:46PM +0300, Alexander Popov wrote:
> On 19.04.2018 16:49, Uwe Kleine-König wrote:
> >> @@ -280,6 +280,7 @@ static noinline int i2cdev_ioctl_rdwr(struct i2c_client *client,
> >> */
> >> if (msgs[i].flags & I2C_M_RECV_LEN) {
> >> if (!(msgs[i].flags & I2C_M_RD) ||
> >> + !msgs[i].len ||
> >
> > I'd prefer
> >
> > msgs[i].len > 0
>
> Excuse me, it will be wrong. We stop if len is 0 to avoid the following
> ZERO_SIZE_PTR dereference.
right you are. I missed the negation.
> > here instead of
> >
> > !msgs[i].len
>
> I can change it to "msgs[i].len == 0". But is it really important?
>
> I've carefully tested the current version with the original repro. It works correct.
I don't doubt it, and the code generated is maybe even the same. The
point I wanted to make is that
!len
is harder to read for a human than
len < 1
(or another suitable arithmetic expression). But feel free to disagree
and keep the code as is.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |
