Re: [PATCH] tools/bpftool: silence a static check warning

[Daniel Borkmann]

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.carpen...@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