From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [PATCH] tools/bpftool: silence a static check warning
Date: Mon, 15 Jan 2018 11:35:06 +0100
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References: <20180115081547.bf2u3aqitnm3bmtl@mwanda>
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Cc: netdev@vger.kernel.org, kernel-janitors@vger.kernel.org
To: Dan Carpenter <dan.carpenter@oracle.com>,
        Alexei Starovoitov <ast@kernel.org>
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Hi Dan,

On 01/15/2018 09:15 AM, Dan Carpenter wrote:
> There is a static checker warning that proglen has an upper bound but no
> lower bound.  The allocation will just fail harmlessly so it's not a big
> deal.
> 
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> 
> diff --git a/tools/bpf/bpf_jit_disasm.c b/tools/bpf/bpf_jit_disasm.c
> index 30044bc4f389..2d7bb5dc0b8c 100644
> --- a/tools/bpf/bpf_jit_disasm.c
> +++ b/tools/bpf/bpf_jit_disasm.c
> @@ -205,7 +205,7 @@ static uint8_t *get_last_jit_image(char *haystack, size_t hlen,
>  		regfree(&regex);
>  		return NULL;
>  	}
> -	if (proglen > 1000000) {
> +	if (proglen < 0 || proglen > 1000000) {

Could you just change proglen into unsigned? It's parsing the bpf_jit_dump()
and there we use proglen=%u anyway.

>  		printf("proglen of %d too big, stopping\n", proglen);
>  		return NULL;
>  	}
> 

Thanks,
Daniel