netdev - Re: [PATCH v2 bpf-next 2/3] bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit.

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Date:   Mon, 1 Nov 2021 16:06:25 -0700
From:   Alexei Starovoitov <alexei.starovoitov@...il.com>
To:     Yonghong Song <yhs@...com>
Cc:     "David S. Miller" <davem@...emloft.net>,
        Daniel Borkmann <daniel@...earbox.net>,
        Andrii Nakryiko <andrii@...nel.org>,
        Network Development <netdev@...r.kernel.org>,
        bpf <bpf@...r.kernel.org>, Kernel Team <kernel-team@...com>
Subject: Re: [PATCH v2 bpf-next 2/3] bpf: Fix propagation of signed bounds
 from 64-bit min/max into 32-bit.

On Mon, Nov 1, 2021 at 4:03 PM Yonghong Song <yhs@...com> wrote:
>
>
>
> On 11/1/21 3:21 PM, Alexei Starovoitov wrote:
> > From: Alexei Starovoitov <ast@...nel.org>
> >
> > Similar to unsigned bounds propagation fix signed bounds.
> > The 'Fixes' tag is a hint. There is no security bug here.
> > The verifier was too conservative.
> >
> > Fixes: 3f50f132d840 ("bpf: Verifier, do explicit ALU32 bounds tracking")
> > Signed-off-by: Alexei Starovoitov <ast@...nel.org>
>
> The change looks good. Should a new test_verifier test be added
> to exercise the new change?

I think manually string comparing output the way VERBOSE_ACCEPT is doing
is an overkill here.
The real test case in .c will take some time to craft.