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From:   Song Liu <songliubraving@fb.com>
To:     Daniel Xu <dxu@dxuuu.xyz>
CC:     bpf <bpf@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "ast@kernel.org" <ast@kernel.org>,
        "daniel@iogearbox.net" <daniel@iogearbox.net>,
        "andrii.nakryiko@gmail.com" <andrii.nakryiko@gmail.com>,
        Kernel Team <Kernel-team@fb.com>
Subject: Re: [PATCH bpf v4 2/2] selftest/bpf: Test bpf_probe_read_user_str()
 strips trailing bytes after NUL
Thread-Topic: [PATCH bpf v4 2/2] selftest/bpf: Test bpf_probe_read_user_str()
 strips trailing bytes after NUL
Thread-Index: AQHWs9C69mAIq+GkoU68WQgbMwtx0am6PXwA
Date:   Fri, 6 Nov 2020 00:19:58 +0000
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> On Nov 5, 2020, at 4:06 PM, Daniel Xu <dxu@dxuuu.xyz> wrote:
>=20
> Previously, bpf_probe_read_user_str() could potentially overcopy the
> trailing bytes after the NUL due to how do_strncpy_from_user() does the
> copy in long-sized strides. The issue has been fixed in the previous
> commit.
>=20
> This commit adds a selftest that ensures we don't regress
> bpf_probe_read_user_str() again.
>=20
> Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>

LGTM!

Acked-by: Song Liu <songliubraving@fb.com>

[...]