Re: [PATCH] tools/libbpf: signedness bug in btf_dedup_ref_type()

[Andrii Nakryiko <andrii.nakryiko@gmail.com>]

On Thu, Feb 28, 2019 at 5:37 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> On Thu, Feb 28, 2019 at 06:58:29AM +0000, Yonghong Song wrote:
> >
> >
> > On 2/27/19 9:46 PM, Dan Carpenter wrote:
> > > The "ref_type_id" variable needs to be signed for the error handling
> > > to work.
> > >
> > > Fixes: d5caef5b5655 ("btf: add BTF types deduplication algorithm")
> > > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> > > ---
> > > This goes through the BPF tree probably, although it does apply to
> > > net-next.
> > >
> > >   tools/lib/bpf/btf.c | 3 ++-
> > >   1 file changed, 2 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
> > > index 68b50e9bbde1..8faed5386124 100644
> > > --- a/tools/lib/bpf/btf.c
> > > +++ b/tools/lib/bpf/btf.c
> > > @@ -2326,7 +2326,8 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
> > >     struct btf_type *t, *cand;
> > >     /* if we don't find equivalent type, then we are representative type */
> > >     __u32 new_id = type_id;
> > > -   __u32 h, ref_type_id;
> > > +   __u32 h; > +    int ref_type_id;
> >
> > nit. Maybe you can change to
> >       int ref_type_id;
> >       __u32 h;
> > to maintain kernel declaration reverse christmas tree convention?
> >
>
> Yes.  Thanks.  Let me resend.
>

Thanks for catching and fixing this! With Yonghong's suggestion, you can add:

Acked-by: Andrii Nakryiko <andriin@fb.com>


> regards,
> dan carpenter
>