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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 15 Jan 2018 11:35:06 +0100
From:   Daniel Borkmann <daniel@...earbox.net>
To:     Dan Carpenter <dan.carpenter@...cle.com>,
        Alexei Starovoitov <ast@...nel.org>
Cc:     netdev@...r.kernel.org, kernel-janitors@...r.kernel.org
Subject: Re: [PATCH] tools/bpftool: silence a static check warning

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@...cle.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