From helmut at subdivi.de Sat Jul 6 12:05:47 2013 From: helmut at subdivi.de (Helmut Grohne) Date: Sat, 6 Jul 2013 18:05:47 +0200 Subject: [jugglemaster] aajm crash found by mayhem Message-ID: <20130706160546.GA14176@alf.mars> As it was already posted to a public mailinglist I can share the link: http://www.forallsecure.com/bug-reports/e4969ef9717548310e44a97ea017b2c03e124bdd/ Since there is no bug report yet, I write my findings here and will forward them to the bug later. The crashing invocation can be reduced to "aajm -s -". The -s option is to specify a pattern and - is an invalid pattern. In fact any invalid pattern will do. It is passed to jmlib which then calls the error handler provided by aajm. The error handler in turn prints the error using aalib. Unfortunately aalib is not yet initialized at the time arguments are parsed. Boom. What is the best recourse to fix this? a) Start without a callback, check errors explicitly and then replace the callback. b) Have a state variable of whether aalib is initialized and let the callback decide. Thoughts welcome. If this is going to result in a new jugglemaster release, please also have a look at whether you can pick some patches from Debian: http://patch-tracker.debian.org/package/jugglemaster/0.4-6 Helmut