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Message-ID: <c4ca108f891718188ea2a9560324d23de2740565.camel@redhat.com>
Subject: Re: [PATCH v2] bpf: Add length check for
 SK_DIAG_BPF_STORAGE_REQ_MAP_FD parsing
From:   Paolo Abeni <pabeni@redhat.com>
To:     Lin Ma <linma@zju.edu.cn>, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, ast@kernel.org,
        martin.lau@kernel.org, yhs@fb.com, void@manifault.com,
        andrii@kernel.org, houtao1@huawei.com, inwardvessel@gmail.com,
        kuniyu@amazon.com, songliubraving@fb.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, bpf@vger.kernel.org
Date:   Thu, 27 Jul 2023 09:34:41 +0200
In-Reply-To: <20230725023330.422856-1-linma@zju.edu.cn>
References: <20230725023330.422856-1-linma@zju.edu.cn>
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On Tue, 2023-07-25 at 10:33 +0800, Lin Ma wrote:
> The nla_for_each_nested parsing in function bpf_sk_storage_diag_alloc
> does not check the length of the nested attribute. This can lead to an
> out-of-attribute read and allow a malformed nlattr (e.g., length 0) to
> be viewed as a 4 byte integer.
>=20
> This patch adds an additional check when the nlattr is getting counted.
> This makes sure the latter nla_get_u32 can access the attributes with
> the correct length.
>=20
> Fixes: 1ed4d92458a9 ("bpf: INET_DIAG support in bpf_sk_storage")
> Suggested-by: Jakub Kicinski <kuba@kernel.org>
> Signed-off-by: Lin Ma <linma@zju.edu.cn>

I guess this should go via the ebpf tree, right? Setting the delegate
accordingly.=20

Please correct me if I'm wrong.

Thanks!

/P