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Date:   Tue, 21 Nov 2023 21:28:29 -0800
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Subject: Re: [PATCH net] bpf: test_run: fix WARNING in format_decode
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To:     Edward Adam Davis <eadavis@qq.com>,
        syzbot+e2c932aec5c8a6e1d31c@syzkaller.appspotmail.com
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        martin.lau@kernel.org, martin.lau@linux.dev, mhiramat@kernel.org,
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 <tencent_884D1773977426D9D3600371696883B6A405@qq.com>
From:   Yonghong Song <yonghong.song@linux.dev>
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On 11/21/23 7:50 PM, Edward Adam Davis wrote:
> Confirm that skb->len is not 0 to ensure that skb length is valid.
>
> Fixes: 114039b34201 ("bpf: Move skb->len == 0 checks into __bpf_redirect")
> Reported-by: syzbot+e2c932aec5c8a6e1d31c@syzkaller.appspotmail.com
> Signed-off-by: Edward Adam Davis <eadavis@qq.com>

Stan, Could you take a look at this patch?


> ---
>   net/bpf/test_run.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
> index c9fdcc5cdce1..78258a822a5c 100644
> --- a/net/bpf/test_run.c
> +++ b/net/bpf/test_run.c
> @@ -845,6 +845,9 @@ static int convert___skb_to_skb(struct sk_buff *skb, struct __sk_buff *__skb)
>   {
>   	struct qdisc_skb_cb *cb = (struct qdisc_skb_cb *)skb->cb;
>   
> +	if (!skb->len)
> +		return -EINVAL;
> +
>   	if (!__skb)
>   		return 0;
>