From: Peter Pawlowski <redmine@...>
Date: 2009-06-23T06:01:20+09:00
Subject: [ruby-core:23971] [Bug #1678] uninitialized value in ossl_x509store_initialize causes occasional segfault

Bug #1678: uninitialized value in ossl_x509store_initialize causes occasional segfault
http://redmine.ruby-lang.org/issues/show/1678

Author: Peter Pawlowski
Status: Open, Priority: Normal
ruby -v: ruby 1.8.7 (2008-08-11 patchlevel 72) [x86_64-linux] 

I am seeing segfaults when attempting to run gem to install something on my build of Ruby 1.8.7 on a 64-bit linux machine.

When I use valgrind to try to figure out where it's failing, I see this suspicious output:

==19613== Conditional jump or move depends on uninitialised value(s)
==19613==    at 0x60E5059: CRYPTO_set_ex_data (ex_data.c:597)
==19613==    by 0x5E16F25: X509_STORE_set_ex_data (openssl_missing.c:42)
==19613==    by 0x5E1C256: ossl_x509store_set_vfy_cb (ossl_x509store.c:115)
==19613==    by 0x5E1C2DC: ossl_x509store_initialize (ossl_x509store.c:135)
==19613==    by 0x4A48C79: call_cfunc (eval.c:5749)
==19613==    by 0x4A47F7B: rb_call0 (eval.c:5904)
==19613==    by 0x4A49714: rb_call (eval.c:6151)
==19613==    by 0x4A49CEE: rb_funcall2 (eval.c:6287)
==19613==    by 0x4A4CFA3: rb_obj_call_init (eval.c:7770)
==19613==    by 0x4A7C991: rb_class_new_instance (object.c:1644)
==19613==    by 0x4A48C79: call_cfunc (eval.c:5749)
==19613==    by 0x4A47F7B: rb_call0 (eval.c:5904)

This should be easy to reproduce by just running gem install --local <anylocalgem>, which is how I am seeing the problem.

The problem appears to be that the GetX509Store macro is not initializing store->ex_data.sk for some reason.

I'm able to eliminate the problem by adding this line of code to the ossl_x509store_initialize function in ext/openssl/ossl_x509store.c, after the call to GetX509Store:

    store->ex_data.sk = NULL;

but I'm sure that this isn't the proper way to solve the problem. I tried to figure out why this is happening, but I don't understand the code well enough to make a suggestion, or a real patch.

I hope this is all the information you need, please let me know if there's anything else I can supply to help figure this out.


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