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Subject: Re: KASAN: slab-out-of-bounds Read in erspan_xmit
To:     William Tu <u9012063@gmail.com>
Cc:     syzbot <syzbot+9723f2d288e49b492cf0@syzkaller.appspotmail.com>,
        David Miller <davem@davemloft.net>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        linux-kernel@vger.kernel.org,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        syzkaller-bugs@googlegroups.com,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
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 <CALDO+SYScmeUsG5fqngNAuYAZZbPjkfFERKHuKgry_r+W194SA@mail.gmail.com>
From:   David Ahern <dsahern@gmail.com>
Message-ID: <32f1adea-f2e3-9f29-bb1b-1b2116f13903@gmail.com>
Date:   Tue, 23 Jan 2018 11:58:56 -0700
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On 1/23/18 11:50 AM, William Tu wrote:
> Hi,
> 
> I'm new to kasan and trying to follow this instruction to reproduce the issue:
> https://github.com/google/syzkaller/blob/master/docs/executing_syzkaller_programs.md
> 
> After re-compile my kernel with KASAN related config enable, I run
> $ ./syz-execprog -cover=0 -repeat=0 -procs=16 program
> 
> I wonder does the "program" mean the repro.c.txt? or I should compile
> it to binary?
> # gcc -o program repro.c.txt
> # ./syz-execprog myprogram
> 2018/01/23 10:45:19 parsed 0 programs
> 
> And how to use the "repro.syz.txt"?
> It seems to have some command like "syz_emit_ethernet" to generate packet.
> but I have no clue where to run it. Maybe I'm still missing something?
> 

In the past I have only compiled a kernel with KASAN, compiled the
reproducer program and run it in a VM. No need for the syzbot overhead.