From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stefano Brivio <sbrivio@redhat.com>
To: passt-dev@passt.top
Subject:
 Re: [PATCH] tcp: Work around gcc 12 bogus warning in tcp_rtt_dst_check()
Date: Wed, 25 May 2022 13:31:59 +0200
Message-ID: <20220525133159.35be89bc@elisabeth>
In-Reply-To: <Yoyg0XQjhGy6zuzP@yekko>
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="===============8257292829938833822=="

--===============8257292829938833822==
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: quoted-printable

On Tue, 24 May 2022 19:09:37 +1000
David Gibson <david(a)gibson.dropbear.id.au> wrote:

> On Fri, May 20, 2022 at 11:01:11AM +0200, Stefano Brivio wrote:
> > gcc 12.1.x (e.g. current OpenSUSE Tumbleweed, x86_64 only,
> > gcc-12-1.4.x86_64) reports:
> >=20
> > tcp.c: In function =E2=80=98tcp_send_flag=E2=80=99:
> > tcp.c:1014:9: warning: writing 16 bytes into a region of size 0 [-Wstring=
op-overflow=3D]
> >  1014 |         memcpy(low_rtt_dst + hole++, &conn->a.a6, sizeof(conn->a.=
a6));
> >       |         ^
> > tcp.c:559:24: note: at offset -16 into destination object =E2=80=98low_rt=
t_dst=E2=80=99 of size 128
> >   559 | static struct in6_addr low_rtt_dst[LOW_RTT_TABLE_SIZE];
> >       |
> >=20
> > but 'hole' can't be -1, because the low_rtt_dst table is guaranteed
> > to have a hole: if we happened to write to the last entry, we'll go
> > back to index 0 and clear that one.
> >=20
> > Signed-off-by: Stefano Brivio <sbrivio(a)redhat.com> =20
>=20
> Reviewed-by: David Gibson <david(a)gibson.dropbear.id.au>

Thanks for the reviews! I pushed those two changes already on Friday,
as they were both rather simple and blocking continuous integration.

I guess it might make sense to set up Patchwork eventually, but it
feels a bit overkill for the moment...

--=20
Stefano


--===============8257292829938833822==--