Re: [PATCH 0/3] cast sizeof to int for comparison

From: Julia Lawall
Date: Sun Jul 01 2018 - 14:52:20 EST




On Sun, 1 Jul 2018, Joe Perches wrote:

> On Sun, 2018-07-01 at 19:32 +0200, Julia Lawall wrote:
> > Comparing an int to a size, which is unsigned, causes the int to become
> > unsigned, giving the wrong result.
> >
> > The semantic match that finds this problem is as follows:
> > (http://coccinelle.lip6.fr/)
>
> Great, thanks.
>
> But what about the ones in net/smc like:
>
> > net/smc/smc_clc.c:
> >
> > len = kernel_sendmsg(smc->clcsock, &msg, &vec, 1,
> > sizeof(struct smc_clc_msg_decline));
> > if (len < sizeof(struct smc_clc_msg_decline))
>
> Are those detected by the semantic match and ignored?

I wasn't sure how to justify that kernel_sendmsg returns a negative value.
If it is the case, I can send the patch. I only found this in one file,
but there were multiple occurrences.

julia