[racket-dev] fuzz testing the bytecode reader

From: Jay McCarthy (jay.mccarthy at gmail.com)
Date: Tue Oct 19 17:32:02 EDT 2010

I hope it doesn't delete DrDr's hard drive.


On Tue, Oct 19, 2010 at 1:51 PM, Carl Eastlund <cce at ccs.neu.edu> wrote:
> Caveat Emptor: be wary of running code designed to produce random,
> unsafe results if the computer you are running it on has any data you
> really care about.  Chances of catastrophic failure *should* be low,
> but they may not be, and sometimes lightning does strike anyway.
> Carl Eastlund
> On Tue, Oct 19, 2010 at 4:42 PM, Sam Tobin-Hochstadt <samth at ccs.neu.edu> wrote:
>> Earlier today, I wrote a simple fuzz tester for bytecode reading and
>> evaluation. The code is attached.  It takes an existing zo file, reads
>> it in as bytes, randomly flips some small portion of the bits (0.1%),
>> and then `read's and `eval's the results.  This extremely quickly
>> finds segfaults in Racket.  Here's a deterministic segfault with git
>> HEAD:
>> [samth at hermes:~/tmp] racket fuzz.rkt -s  1046626898 -f
>> ~/sw/plt/collects/redex/tests/compiled/lw-test-util_rkt.zo
>> DrDr Ignore! random-seed 1046626898
>> name: /home/samth/sw/plt/collects/redex/tests/compiled/lw-test-util_rkt.zo
>> SIGSEGV MAPERR si_code 1 fault on addr 0x616ec898
>> Aborted
>> Here's how to traverse a bunch of files to find a segfault:
>>> racket fuzz.rkt -d ~/sw/plt/collects/redex/
>> I'll be adding this to the tree in the stress tests soon.
>> Thanks to Robby for advice on the code, and to Lars Hansen for the idea.
>> --
>> sam th
>> samth at ccs.neu.edu
> _________________________________________________
>  For list-related administrative tasks:
>  http://lists.racket-lang.org/listinfo/dev

Jay McCarthy <jay at cs.byu.edu>
Assistant Professor / Brigham Young University

"The glory of God is Intelligence" - D&C 93

Posted on the dev mailing list.