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Diffstat (limited to 'Lib/test/crashers/bogus_sre_bytecode.py')
-rw-r--r-- | Lib/test/crashers/bogus_sre_bytecode.py | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/Lib/test/crashers/bogus_sre_bytecode.py b/Lib/test/crashers/bogus_sre_bytecode.py new file mode 100644 index 0000000..4bfc730 --- /dev/null +++ b/Lib/test/crashers/bogus_sre_bytecode.py @@ -0,0 +1,47 @@ +""" +The regular expression engine in '_sre' can segfault when interpreting +bogus bytecode. + +It is unclear whether this is a real bug or a "won't fix" case like +bogus_code_obj.py, because it requires bytecode that is built by hand, +as opposed to compiled by 're' from a string-source regexp. The +difference with bogus_code_obj, though, is that the only existing regexp +compiler is written in Python, so that the C code has no choice but +accept arbitrary bytecode from Python-level. + +The test below builds and runs random bytecodes until 'match' crashes +Python. I have not investigated why exactly segfaults occur nor how +hard they would be to fix. Here are a few examples of 'code' that +segfault for me: + + [21, 50814, 8, 29, 16] + [21, 3967, 26, 10, 23, 54113] + [29, 23, 0, 2, 5] + [31, 64351, 0, 28, 3, 22281, 20, 4463, 9, 25, 59154, 15245, 2, + 16343, 3, 11600, 24380, 10, 37556, 10, 31, 15, 31] + +Here is also a 'code' that triggers an infinite uninterruptible loop: + + [29, 1, 8, 21, 1, 43083, 6] + +""" + +import _sre, random + +def pick(): + n = random.randrange(-65536, 65536) + if n < 0: + n &= 31 + return n + +ss = ["", "world", "x" * 500] + +while 1: + code = [pick() for i in range(random.randrange(5, 25))] + print code + pat = _sre.compile(None, 0, code) + for s in ss: + try: + pat.match(s) + except RuntimeError: + pass |