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Date: Thu, 11 Sep 2014 21:54:09 +0200
From: Daniel Borkmann <dborkman@redhat.com>
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To: Alexei Starovoitov <ast@plumgrid.com>
CC: Andy Lutomirski <luto@amacapital.net>,
        "David S. Miller" <davem@davemloft.net>,
        Ingo Molnar <mingo@kernel.org>,
        Linus Torvalds <torvalds@linuxfoundation.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Hannes Frederic Sowa <hannes@stressinduktion.org>,
        Chema Gonzalez <chema@google.com>, Eric Dumazet <edumazet@google.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Pablo Neira Ayuso <pablo@netfilter.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Andrew Morton <akpm@linuxfoundation.org>,
        Kees Cook <keescook@chromium.org>,
        Linux API <linux-api@vger.kernel.org>,
        Network Development <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v11 net-next 00/12] eBPF syscall, verifier, testsuite
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On 09/10/2014 10:21 PM, Alexei Starovoitov wrote:
...
>>>                char bpf_log_buf[LOG_BUF_SIZE];
>>
>> What happens if the size isn't LOG_BUF_SIZE?
>
> would do you mean?
> LOG_BUF_SIZE is just a user defined macro.
> Can be anything.

I believe, Andy means, what would happen if log_level > 0 but
the log_size is not big enough so that the human-readable error
text string from the verifier will fit into it? I presume that
will be truncated then ... hm.

> it's passed along with pointer:
>                         .log_buf = bpf_log_buf,
>                         .log_size = LOG_BUF_SIZE,
>                         .log_level = 1,