Date:   Fri, 27 Jan 2023 16:24:17 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Rob Herring <robh+dt@kernel.org>
Cc:     Frank Rowand <frowand.list@gmail.com>, devicetree@vger.kernel.org,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH] scripts/dtc: Replace 0-length arrays with flexible arrays
Message-ID: <202301271624.01B4A55D3C@keescook>
References: <20230127224101.never.746-kees@kernel.org>
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 <202301271609.15F0E5EB15@keescook>
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On Fri, Jan 27, 2023 at 04:12:21PM -0800, Kees Cook wrote:
> On Fri, Jan 27, 2023 at 05:44:13PM -0600, Rob Herring wrote:
> > On Fri, Jan 27, 2023 at 4:41 PM Kees Cook <keescook@chromium.org> wrote:
> > >
> > > Replace the 0-length array with a C99 flexible array. Seen with GCC 13
> > > under -fstrict-flex-arrays:
> > >
> > > In file included from ../lib/fdt_ro.c:2:
> > > ../lib/../scripts/dtc/libfdt/fdt_ro.c: In function 'fdt_get_name':
> > > ../lib/../scripts/dtc/libfdt/fdt_ro.c:319:24: warning: 'strrchr' reading 1 or more bytes from a region of size 0 [-Wstringop-overread]
> > >   319 |                 leaf = strrchr(nameptr, '/');
> > >       |                        ^~~~~~~~~~~~~~~~~~~~~
> > >
> > > Cc: Rob Herring <robh+dt@kernel.org>
> > > Cc: Frank Rowand <frowand.list@gmail.com>
> > > Cc: devicetree@vger.kernel.org
> > > Signed-off-by: Kees Cook <keescook@chromium.org>
> > > ---
> > >  scripts/dtc/libfdt/fdt.h | 4 ++--
> > >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > Changes to dtc/libfdt go to upstream dtc first and then we sync them back.
> 
> Ah-ha, I've found it: https://github.com/dgibson/dtc

Sent upstream: https://github.com/dgibson/dtc/pull/76

-- 
Kees Cook