Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date: Thu, 6 Aug 2015 19:38:49 +0300
From: Solar Designer <>
Subject: --test-full=0 crashes the Bitcoin format

Kai, magnum -

Flag bugs aside, this feature as committed to magnum's jumbo triggers
memory corruption:

[ run]$ ./john --test-full=0
Testing: asa-md5, Cisco ASA [Cisco ASA (MD5 salted) 128/128 AVX 4x3]... PASS
Testing: bfegg, Eggdrop [Blowfish 32/64]... (32xOMP) PASS
Testing: Bitcoin [SHA512 AES 128/128 AVX 2x]... (32xOMP) *** glibc detected *** ./john: double free or corruption (!prev): 0x000000000224a770 ***
======= Backtrace: =========

This is for today's jumbo built on super after "scl enable devtoolset-3
bash" (so with gcc 4.9.1).  ./configure was run without options (so
OpenMP and OpenCL are enabled, CUDA is disabled).

Would you debug this, please?

It's probably some bug unrelated to flags, which merely happened to be
triggered in this run.  I'd start by testing if it's triggerable
reliably or not, and whether it's triggerable without OpenMP at all.
Also, whether it's triggerable when the Bitcoin format is test-full'ed
on its own (rather than after lots of other formats).  Then try to
trigger it in an --enable-asan build (hopefully, it'd crash on the
actual memory corruption, not on its aftermath as this run did).

... After writing the above, I ran the command a few more times.  Most
of the time, there's no crash.  But I was able to trigger the crash
once more (so 2 times total so far), with GOMP_CPU_AFFINITY=0-31.  ASan
should help detect it reliably.


Powered by blists - more mailing lists

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.