HexBrain

shopify-scripts · Report #185794

Crash: mrb_any_to_s can't handle NilClass, Symbol and Fixnum

Validstatus
highseverity
$8,000bounty
4upvotes
16 Dec 2016disclosed

How it was found

When using boxing_word.h (haven't tested other boxing methods yet), mrb_any_to_s is unable to handle NilClass, Symbol and Fixnum. This can be achieved by just deleting :to_s from the class and let mrb_any_to_s crash.

I tried to come up with a fix but I'm not 100% sure where this should be fixed. The boxing schemas all work slightly different so fixing mrb_any_to_s in a way that it respects the boxing schema is not my preferred choice (as implementation details shouldn't bleed through to that method). I guess it's either the right call to make mrb_any_to_s always safe or pull part of the functionality into the specific boxing header.

#PoC Works with Symbol and Fixnum as well:

NilClass.remove_method :to_s
nil.to_s

#Traces

Sandbox:

bin/sandbox_extract crashes/nil_remove_to_s.mrb
bin/sandbox_extract:20: [BUG] Segmentation fault at 0x00000000000018
ruby 2.3.3p222 (2016-11-21 revision 56859) [x86_64-linux]

-- Control frame information -----------------------------------------------
c:0003 p:---- s:0010 e:000009 CFUNC  :sandbox_eval
c:0002 p:0201 s:0005 E:000368 EVAL   bin/sandbox_extract:20 [FINISH]
c:0001 p:0000 s:0002 E:0021f0 (none) [FINISH]

-- Ruby level backtrace information ----------------------------------------
bin/sandbox_extract:20:in `<main>'
bin/sandbox_extract:20:in `sandbox_eval'

-- Machine register context ------------------------------------------------
 RIP: 0x00007fb466086787 RBP: 0x00007fb464c15100 RSP: 0x00007fb464c0bab0
 RAX: 0x00007fb464c15100 RBX: 0x00007fb464c0d4e0 RCX: 0x000000000000003a
 RDX: 0x0000000000000110 RDI: 0x00007fb464c4ef3a RSI: 0x00007fb46610ca2e
  R8: 0x0000000000000003  R9: 0x0000000000000000 R10: 0x0000000000000262
 R11: 0x00007fb466090d40 R12: 0x0000000000000000 R13: 0x00007fb464c150b8
 R14: 0x00007fb464c0d4e0 R15: 0x00007fb464c18220 EFL: 0x0000000000010206

-- C level backtrace information -------------------------------------------
/usr/lib/libruby.so.2.3 [0x7fb46a16d455]
/usr/lib/libruby.so.2.3 [0x7fb46a16d68c]
/usr/lib/libruby.so.2.3 [0x7fb46a047e34]
/usr/lib/libruby.so.2.3 [0x7fb46a0f96ce]
/usr/lib/libc.so.6 [0x7fb469c6d0b0]
/home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so(mrb_any_to_s+0x67) [0x7fb466086787] /home/simon/git/shopify/mruby-engine/ext/mruby_engine/mruby/src/object.c:442
/home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so(mrb_vm_exec+0x762) [0x7fb466097952] /home/simon/git/shopify/mruby-engine/ext/mruby_engine/mruby/src/vm.c:1165
/home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so(mrb_vm_run+0x57) [0x7fb46609d627] /home/simon/git/shopify/mruby-engine/ext/mruby_engine/mruby/src/vm.c:766
/home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so(mruby_engine_monitored_eval+0x113) [0x7fb46607c8c3] ../../../../ext/mruby_engine/eval_monitored.c:68
/usr/lib/libpthread.so.0(start_thread+0xc4) [0x7fb469a24454]
/usr/lib/libc.so.6(clone+0x5f) [0x7fb469d227df]

-- Other runtime information -----------------------------------------------

* Loaded script: bin/sandbox_extract

* Loaded features:

    0 enumerator.so
    1 thread.rb
    2 rational.so
    3 complex.so
    4 /usr/lib/ruby/2.3.0/x86_64-linux/enc/encdb.so
    5 /usr/lib/ruby/2.3.0/x86_64-linux/enc/trans/transdb.so
    6 /usr/lib/ruby/2.3.0/unicode_normalize.rb
    7 /usr/lib/ruby/2.3.0/x86_64-linux/rbconfig.rb
    8 /usr/lib/ruby/2.3.0/rubygems/compatibility.rb
    9 /usr/lib/ruby/2.3.0/rubygems/defaults.rb
   10 /usr/lib/ruby/2.3.0/rubygems/deprecate.rb
   11 /usr/lib/ruby/2.3.0/rubygems/errors.rb
   12 /usr/lib/ruby/2.3.0/rubygems/version.rb
   13 /usr/lib/ruby/2.3.0/rubygems/requirement.rb
   14 /usr/lib/ruby/2.3.0/rubygems/platform.rb
   15 /usr/lib/ruby/2.3.0/rubygems/basic_specification.rb
   16 /usr/lib/ruby/2.3.0/rubygems/stub_specification.rb
   17 /usr/lib/ruby/2.3.0/rubygems/util/list.rb
   18 /usr/lib/ruby/2.3.0/x86_64-linux/stringio.so
   19 /usr/lib/ruby/2.3.0/rubygems/specification.rb
   20 /usr/lib/ruby/2.3.0/rubygems/exceptions.rb
   21 /usr/lib/ruby/2.3.0/rubygems/dependency.rb
   22 /usr/lib/ruby/2.3.0/rubygems/core_ext/kernel_gem.rb
   23 /usr/lib/ruby/2.3.0/monitor.rb
   24 /usr/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb
   25 /usr/lib/ruby/2.3.0/rubygems.rb
   26 /usr/lib/ruby/2.3.0/rubygems/path_support.rb
   27 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/version.rb
   28 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/core_ext/name_error.rb
   29 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/levenshtein.rb
   30 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/jaro_winkler.rb
   31 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/spell_checkable.rb
   32 /usr/lib/ruby/2.3.0/delegate.rb
   33 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/spell_checkers/name_error_checkers/class_name_checker.rb
   34 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/spell_checkers/name_error_checkers/variable_name_checker.rb
   35 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/spell_checkers/name_error_checkers.rb
   36 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/spell_checkers/method_name_checker.rb
   37 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/spell_checkers/null_checker.rb
   38 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean/formatter.rb
   39 /usr/lib/ruby/gems/2.3.0/gems/did_you_mean-1.0.0/lib/did_you_mean.rb
   40 /usr/lib/ruby/2.3.0/x86_64-linux/pathname.so
   41 /usr/lib/ruby/2.3.0/pathname.rb
   42 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/postit_trampoline.rb
   43 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/constants.rb
   44 /usr/lib/ruby/2.3.0/x86_64-linux/io/console.so
   45 /usr/lib/ruby/2.3.0/rubygems/user_interaction.rb
   46 /usr/lib/ruby/2.3.0/x86_64-linux/etc.so
   47 /usr/lib/ruby/2.3.0/rubygems/config_file.rb
   48 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/rubygems_integration.rb
   49 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/current_ruby.rb
   50 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/shared_helpers.rb
   51 /usr/lib/ruby/2.3.0/fileutils.rb
   52 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/errors.rb
   53 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/environment_preserver.rb
   54 /usr/lib/ruby/2.3.0/x86_64-linux/socket.so
   55 /usr/lib/ruby/2.3.0/x86_64-linux/io/wait.so
   56 /usr/lib/ruby/2.3.0/socket.rb
   57 /usr/lib/ruby/2.3.0/timeout.rb
   58 /usr/lib/ruby/2.3.0/net/protocol.rb
   59 /usr/lib/ruby/2.3.0/uri/rfc2396_parser.rb
   60 /usr/lib/ruby/2.3.0/uri/rfc3986_parser.rb
   61 /usr/lib/ruby/2.3.0/uri/common.rb
   62 /usr/lib/ruby/2.3.0/uri/generic.rb
   63 /usr/lib/ruby/2.3.0/uri/ftp.rb
   64 /usr/lib/ruby/2.3.0/uri/http.rb
   65 /usr/lib/ruby/2.3.0/uri/https.rb
   66 /usr/lib/ruby/2.3.0/uri/ldap.rb
   67 /usr/lib/ruby/2.3.0/uri/ldaps.rb
   68 /usr/lib/ruby/2.3.0/uri/mailto.rb
   69 /usr/lib/ruby/2.3.0/uri.rb
   70 /usr/lib/ruby/2.3.0/x86_64-linux/zlib.so
   71 /usr/lib/ruby/2.3.0/net/http/exceptions.rb
   72 /usr/lib/ruby/2.3.0/net/http/header.rb
   73 /usr/lib/ruby/2.3.0/x86_64-linux/enc/windows_31j.so
   74 /usr/lib/ruby/2.3.0/net/http/generic_request.rb
   75 /usr/lib/ruby/2.3.0/net/http/request.rb
   76 /usr/lib/ruby/2.3.0/net/http/requests.rb
   77 /usr/lib/ruby/2.3.0/net/http/response.rb
   78 /usr/lib/ruby/2.3.0/net/http/responses.rb
   79 /usr/lib/ruby/2.3.0/net/http/proxy_delta.rb
   80 /usr/lib/ruby/2.3.0/net/http/backward.rb
   81 /usr/lib/ruby/2.3.0/net/http.rb
   82 /usr/lib/ruby/2.3.0/x86_64-linux/date_core.so
   83 /usr/lib/ruby/2.3.0/date.rb
   84 /usr/lib/ruby/2.3.0/time.rb
   85 /usr/lib/ruby/2.3.0/rubygems/request/http_pool.rb
   86 /usr/lib/ruby/2.3.0/rubygems/request/https_pool.rb
   87 /usr/lib/ruby/2.3.0/rubygems/request/connection_pools.rb
   88 /usr/lib/ruby/2.3.0/rubygems/request.rb
   89 /usr/lib/ruby/2.3.0/cgi/core.rb
   90 /usr/lib/ruby/2.3.0/x86_64-linux/cgi/escape.so
   91 /usr/lib/ruby/2.3.0/cgi/util.rb
   92 /usr/lib/ruby/2.3.0/cgi/cookie.rb
   93 /usr/lib/ruby/2.3.0/cgi.rb
   94 /usr/lib/ruby/2.3.0/rubygems/uri_formatter.rb
   95 /usr/lib/ruby/2.3.0/x86_64-linux/digest.so
   96 /usr/lib/ruby/2.3.0/digest.rb
   97 /usr/lib/ruby/2.3.0/x86_64-linux/openssl.so
   98 /usr/lib/ruby/2.3.0/openssl/bn.rb
   99 /usr/lib/ruby/2.3.0/openssl/pkey.rb
  100 /usr/lib/ruby/2.3.0/openssl/cipher.rb
  101 /usr/lib/ruby/2.3.0/openssl/config.rb
  102 /usr/lib/ruby/2.3.0/openssl/digest.rb
  103 /usr/lib/ruby/2.3.0/openssl/x509.rb
  104 /usr/lib/ruby/2.3.0/openssl/buffering.rb
  105 /usr/lib/ruby/2.3.0/x86_64-linux/io/nonblock.so
  106 /usr/lib/ruby/2.3.0/openssl/ssl.rb
  107 /usr/lib/ruby/2.3.0/openssl.rb
  108 /usr/lib/ruby/2.3.0/securerandom.rb
  109 /usr/lib/ruby/2.3.0/resolv.rb
  110 /usr/lib/ruby/2.3.0/rubygems/remote_fetcher.rb
  111 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/gem_remote_fetcher.rb
  112 /usr/lib/ruby/2.3.0/x86_64-linux/digest/sha1.so
  113 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/plugin/api/source.rb
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  115 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/plugin.rb
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  124 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/gem_helpers.rb
  125 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/match_platform.rb
  126 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/rubygems_ext.rb
  127 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/version.rb
  128 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler.rb
  129 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/settings.rb
  130 /usr/lib/ruby/2.3.0/rubygems/ext/build_error.rb
  131 /usr/lib/ruby/2.3.0/rubygems/ext/builder.rb
  132 /usr/lib/ruby/2.3.0/rubygems/ext/configure_builder.rb
  133 /usr/lib/ruby/2.3.0/tmpdir.rb
  134 /usr/lib/ruby/2.3.0/tempfile.rb
  135 /usr/lib/ruby/2.3.0/rubygems/ext/ext_conf_builder.rb
  136 /usr/lib/ruby/2.3.0/rubygems/ext/rake_builder.rb
  137 /usr/lib/ruby/2.3.0/optparse.rb
  138 /usr/lib/ruby/2.3.0/rubygems/command.rb
  139 /usr/lib/ruby/2.3.0/rubygems/ext/cmake_builder.rb
  140 /usr/lib/ruby/2.3.0/rubygems/ext.rb
  141 /usr/lib/ruby/2.3.0/x86_64-linux/strscan.so
  142 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/source.rb
  143 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/source/path.rb
  144 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/source/git.rb
  145 /usr/lib/ruby/2.3.0/rubygems/text.rb
  146 /usr/lib/ruby/2.3.0/rubygems/name_tuple.rb
  147 /usr/lib/ruby/2.3.0/rubygems/spec_fetcher.rb
  148 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/source/rubygems.rb
  149 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/lockfile_parser.rb
  150 /usr/lib/ruby/2.3.0/set.rb
  151 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/definition.rb
  152 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/dependency.rb
  153 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/ruby_dsl.rb
  154 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/dsl.rb
  155 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/source_list.rb
  156 /home/simon/git/shopify/mruby-engine/lib/mruby_engine/version.rb
  157 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/index.rb
  158 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/source/gemspec.rb
  159 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/lazy_specification.rb
  160 /usr/lib/ruby/2.3.0/tsort.rb
  161 /usr/lib/ruby/2.3.0/forwardable.rb
  162 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/spec_set.rb
  163 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/gem_version_promoter.rb
  164 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/runtime.rb
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  166 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/ui/silent.rb
  167 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/ui/rg_proxy.rb
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  170 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/dep_proxy.rb
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  174 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_edge_no_circular.rb
  175 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_vertex.rb
  176 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/detach_vertex_named.rb
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  184 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/vendor/molinillo/lib/molinillo/delegates/resolution_state.rb
  185 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/vendor/molinillo/lib/molinillo/delegates/specification_provider.rb
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  187 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/vendor/molinillo/lib/molinillo/resolver.rb
  188 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/vendor/molinillo/lib/molinillo/modules/ui.rb
  189 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/vendor/molinillo/lib/molinillo.rb
  190 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/vendored_molinillo.rb
  191 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/resolver.rb
  192 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/endpoint_specification.rb
  193 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/stub_specification.rb
  194 /home/simon/.gem/ruby/2.3.0/gems/bundler-1.13.6/lib/bundler/setup.rb
  195 /usr/lib/ruby/2.3.0/json/version.rb
  196 /usr/lib/ruby/2.3.0/ostruct.rb
  197 /usr/lib/ruby/2.3.0/json/generic_object.rb
  198 /usr/lib/ruby/2.3.0/json/common.rb
  199 /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16be.so
  200 /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16le.so
  201 /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32be.so
  202 /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32le.so
  203 /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/parser.so
  204 /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/generator.so
  205 /usr/lib/ruby/2.3.0/json/ext.rb
  206 /usr/lib/ruby/2.3.0/json.rb
  207 /home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so
  208 /home/simon/git/shopify/mruby-engine/lib/mruby_engine.rb

* Process memory map:

00400000-00401000 r-xp 00000000 08:03 948907                             /usr/bin/ruby
00600000-00601000 r--p 00000000 08:03 948907                             /usr/bin/ruby
00601000-00602000 rw-p 00001000 08:03 948907                             /usr/bin/ruby
00674000-01729000 rw-p 00000000 00:00 0                                  [heap]
7fb45f935000-7fb45fd84000 r--s 00000000 08:04 1838957                    /home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so
7fb45fd84000-7fb460000000 r--s 00000000 08:03 936075                     /usr/lib/libruby.so.2.3.0
7fb460000000-7fb460021000 rw-p 00000000 00:00 0 
7fb460021000-7fb464000000 ---p 00000000 00:00 0 
7fb464018000-7fb4641f5000 r--s 00000000 08:03 934952                     /usr/lib/libc-2.24.so
7fb4641f5000-7fb46420b000 r-xp 00000000 08:03 935430                     /usr/lib/libgcc_s.so.1
7fb46420b000-7fb46440a000 ---p 00016000 08:03 935430                     /usr/lib/libgcc_s.so.1
7fb46440a000-7fb46440b000 r--p 00015000 08:03 935430                     /usr/lib/libgcc_s.so.1
7fb46440b000-7fb46440c000 rw-p 00016000 08:03 935430                     /usr/lib/libgcc_s.so.1
7fb46440c000-7fb46440d000 ---p 00000000 00:00 0 
7fb46440d000-7fb46500d000 rw-p 00000000 00:00 0 
7fb46500d000-7fb465014000 r-xp 00000000 08:03 1061028                    /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/generator.so
7fb465014000-7fb465214000 ---p 00007000 08:03 1061028                    /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/generator.so
7fb465214000-7fb465215000 r--p 00007000 08:03 1061028                    /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/generator.so
7fb465215000-7fb465216000 rw-p 00008000 08:03 1061028                    /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/generator.so
7fb465216000-7fb465217000 r-xp 00000000 08:03 948492                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32le.so
7fb465217000-7fb465416000 ---p 00001000 08:03 948492                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32le.so
7fb465416000-7fb465417000 r--p 00000000 08:03 948492                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32le.so
7fb465417000-7fb465418000 rw-p 00001000 08:03 948492                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32le.so
7fb465418000-7fb465419000 r-xp 00000000 08:03 948496                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32be.so
7fb465419000-7fb465618000 ---p 00001000 08:03 948496                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32be.so
7fb465618000-7fb465619000 r--p 00000000 08:03 948496                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32be.so
7fb465619000-7fb46561a000 rw-p 00001000 08:03 948496                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_32be.so
7fb46561a000-7fb46561b000 r-xp 00000000 08:03 948511                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16le.so
7fb46561b000-7fb46581b000 ---p 00001000 08:03 948511                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16le.so
7fb46581b000-7fb46581c000 r--p 00001000 08:03 948511                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16le.so
7fb46581c000-7fb46581d000 rw-p 00002000 08:03 948511                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16le.so
7fb46581d000-7fb46581e000 r-xp 00000000 08:03 948515                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16be.so
7fb46581e000-7fb465a1e000 ---p 00001000 08:03 948515                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16be.so
7fb465a1e000-7fb465a1f000 r--p 00001000 08:03 948515                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16be.so
7fb465a1f000-7fb465a20000 rw-p 00002000 08:03 948515                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/utf_16be.so
7fb465a20000-7fb465a26000 r-xp 00000000 08:03 1061029                    /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/parser.so
7fb465a26000-7fb465c25000 ---p 00006000 08:03 1061029                    /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/parser.so
7fb465c25000-7fb465c26000 r--p 00005000 08:03 1061029                    /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/parser.so
7fb465c26000-7fb465c27000 rw-p 00006000 08:03 1061029                    /usr/lib/ruby/2.3.0/x86_64-linux/json/ext/parser.so
7fb465c27000-7fb465c4c000 r-xp 00000000 08:03 920898                     /usr/lib/liblzma.so.5.2.2
7fb465c4c000-7fb465e4b000 ---p 00025000 08:03 920898                     /usr/lib/liblzma.so.5.2.2
7fb465e4b000-7fb465e4c000 r--p 00024000 08:03 920898                     /usr/lib/liblzma.so.5.2.2
7fb465e4c000-7fb465e4d000 rw-p 00025000 08:03 920898                     /usr/lib/liblzma.so.5.2.2
7fb465e4d000-7fb465e58000 r-xp 00000000 08:03 944077                     /usr/lib/libunwind.so.8.0.1
7fb465e58000-7fb466057000 ---p 0000b000 08:03 944077                     /usr/lib/libunwind.so.8.0.1
7fb466057000-7fb466058000 r--p 0000a000 08:03 944077                     /usr/lib/libunwind.so.8.0.1
7fb466058000-7fb466059000 rw-p 0000b000 08:03 944077                     /usr/lib/libunwind.so.8.0.1
7fb466059000-7fb466067000 rw-p 00000000 00:00 0 
7fb466067000-7fb46614d000 r-xp 00000000 08:04 1838957                    /home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so
7fb46614d000-7fb46634c000 ---p 000e6000 08:04 1838957                    /home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so
7fb46634c000-7fb46634e000 r--p 000e5000 08:04 1838957                    /home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so
7fb46634e000-7fb466350000 rw-p 000e7000 08:04 1838957                    /home/simon/git/shopify/mruby-engine/lib/mruby_engine/mruby_engine.so
7fb466350000-7fb466355000 r-xp 00000000 08:03 948469                     /usr/lib/ruby/2.3.0/x86_64-linux/strscan.so
7fb466355000-7fb466554000 ---p 00005000 08:03 948469                     /usr/lib/ruby/2.3.0/x86_64-linux/strscan.so
7fb466554000-7fb466555000 r--p 00004000 08:03 948469                     /usr/lib/ruby/2.3.0/x86_64-linux/strscan.so
7fb466555000-7fb466556000 rw-p 00005000 08:03 948469                     /usr/lib/ruby/2.3.0/x86_64-linux/strscan.so
7fb466556000-7fb466557000 r-xp 00000000 08:03 948523                     /usr/lib/ruby/2.3.0/x86_64-linux/digest/sha1.so
7fb466557000-7fb466756000 ---p 00001000 08:03 948523                     /usr/lib/ruby/2.3.0/x86_64-linux/digest/sha1.so
7fb466756000-7fb466757000 r--p 00000000 08:03 948523                     /usr/lib/ruby/2.3.0/x86_64-linux/digest/sha1.so
7fb466757000-7fb466758000 rw-p 00001000 08:03 948523                     /usr/lib/ruby/2.3.0/x86_64-linux/digest/sha1.so
7fb466758000-7fb466759000 r-xp 00000000 08:03 948521                     /usr/lib/ruby/2.3.0/x86_64-linux/io/nonblock.so
7fb466759000-7fb466959000 ---p 00001000 08:03 948521                     /usr/lib/ruby/2.3.0/x86_64-linux/io/nonblock.so
7fb466959000-7fb46695a000 r--p 00001000 08:03 948521                     /usr/lib/ruby/2.3.0/x86_64-linux/io/nonblock.so
7fb46695a000-7fb46695b000 rw-p 00002000 08:03 948521                     /usr/lib/ruby/2.3.0/x86_64-linux/io/nonblock.so
7fb46695b000-7fb46695e000 r-xp 00000000 08:03 948452                     /usr/lib/ruby/2.3.0/x86_64-linux/digest.so
7fb46695e000-7fb466b5d000 ---p 00003000 08:03 948452                     /usr/lib/ruby/2.3.0/x86_64-linux/digest.so
7fb466b5d000-7fb466b5e000 r--p 00002000 08:03 948452                     /usr/lib/ruby/2.3.0/x86_64-linux/digest.so
7fb466b5e000-7fb466b5f000 rw-p 00003000 08:03 948452                     /usr/lib/ruby/2.3.0/x86_64-linux/digest.so
7fb466b5f000-7fb466dad000 r-xp 00000000 08:03 935797                     /usr/lib/libcrypto.so.1.0.0
7fb466dad000-7fb466fac000 ---p 0024e000 08:03 935797                     /usr/lib/libcrypto.so.1.0.0
7fb466fac000-7fb466fc8000 r--p 0024d000 08:03 935797                     /usr/lib/libcrypto.so.1.0.0
7fb466fc8000-7fb466fd4000 rw-p 00269000 08:03 935797                     /usr/lib/libcrypto.so.1.0.0
7fb466fd4000-7fb466fd7000 rw-p 00000000 00:00 0 
7fb466fd7000-7fb46703e000 r-xp 00000000 08:03 935796                     /usr/lib/libssl.so.1.0.0
7fb46703e000-7fb46723d000 ---p 00067000 08:03 935796                     /usr/lib/libssl.so.1.0.0
7fb46723d000-7fb467241000 r--p 00066000 08:03 935796                     /usr/lib/libssl.so.1.0.0
7fb467241000-7fb467248000 rw-p 0006a000 08:03 935796                     /usr/lib/libssl.so.1.0.0
7fb467248000-7fb467297000 r-xp 00000000 08:03 948468                     /usr/lib/ruby/2.3.0/x86_64-linux/openssl.so
7fb467297000-7fb467497000 ---p 0004f000 08:03 948468                     /usr/lib/ruby/2.3.0/x86_64-linux/openssl.so
7fb467497000-7fb467499000 r--p 0004f000 08:03 948468                     /usr/lib/ruby/2.3.0/x86_64-linux/openssl.so
7fb467499000-7fb46749b000 rw-p 00051000 08:03 948468                     /usr/lib/ruby/2.3.0/x86_64-linux/openssl.so
7fb46749b000-7fb46749c000 rw-p 00000000 00:00 0 
7fb46749c000-7fb46749d000 r-xp 00000000 08:03 948519                     /usr/lib/ruby/2.3.0/x86_64-linux/cgi/escape.so
7fb46749d000-7fb46769d000 ---p 00001000 08:03 948519                     /usr/lib/ruby/2.3.0/x86_64-linux/cgi/escape.so
7fb46769d000-7fb46769e000 r--p 00001000 08:03 948519                     /usr/lib/ruby/2.3.0/x86_64-linux/cgi/escape.so
7fb46769e000-7fb46769f000 rw-p 00002000 08:03 948519                     /usr/lib/ruby/2.3.0/x86_64-linux/cgi/escape.so
7fb46769f000-7fb4676ce000 r-xp 00000000 08:03 948450                     /usr/lib/ruby/2.3.0/x86_64-linux/date_core.so
7fb4676ce000-7fb4678ce000 ---p 0002f000 08:03 948450                     /usr/lib/ruby/2.3.0/x86_64-linux/date_core.so
7fb4678ce000-7fb4678cf000 r--p 0002f000 08:03 948450                     /usr/lib/ruby/2.3.0/x86_64-linux/date_core.so
7fb4678cf000-7fb4678d0000 rw-p 00030000 08:03 948450                     /usr/lib/ruby/2.3.0/x86_64-linux/date_core.so
7fb4678d0000-7fb4678d1000 rw-p 00000000 00:00 0 
7fb4678d1000-7fb4678d4000 r-xp 00000000 08:03 948498                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/windows_31j.so
7fb4678d4000-7fb467ad3000 ---p 00003000 08:03 948498                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/windows_31j.so
7fb467ad3000-7fb467ad4000 r--p 00002000 08:03 948498                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/windows_31j.so
7fb467ad4000-7fb467ad5000 rw-p 00003000 08:03 948498                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/windows_31j.so
7fb467ad5000-7fb467aea000 r-xp 00000000 08:03 935844                     /usr/lib/libz.so.1.2.8
7fb467aea000-7fb467ce9000 ---p 00015000 08:03 935844                     /usr/lib/libz.so.1.2.8
7fb467ce9000-7fb467cea000 r--p 00014000 08:03 935844                     /usr/lib/libz.so.1.2.8
7fb467cea000-7fb467ceb000 rw-p 00015000 08:03 935844                     /usr/lib/libz.so.1.2.8
7fb467ceb000-7fb467cf8000 r-xp 00000000 08:03 948479                     /usr/lib/ruby/2.3.0/x86_64-linux/zlib.so
7fb467cf8000-7fb467ef7000 ---p 0000d000 08:03 948479                     /usr/lib/ruby/2.3.0/x86_64-linux/zlib.so
7fb467ef7000-7fb467ef8000 r--p 0000c000 08:03 948479                     /usr/lib/ruby/2.3.0/x86_64-linux/zlib.so
7fb467ef8000-7fb467ef9000 rw-p 0000d000 08:03 948479                     /usr/lib/ruby/2.3.0/x86_64-linux/zlib.so
7fb467ef9000-7fb467efb000 r-xp 00000000 08:03 948520                     /usr/lib/ruby/2.3.0/x86_64-linux/io/wait.so
7fb467efb000-7fb4680fa000 ---p 00002000 08:03 948520                     /usr/lib/ruby/2.3.0/x86_64-linux/io/wait.so
7fb4680fa000-7fb4680fb000 r--p 00001000 08:03 948520                     /usr/lib/ruby/2.3.0/x86_64-linux/io/wait.so
7fb4680fb000-7fb4680fc000 rw-p 00002000 08:03 948520                     /usr/lib/ruby/2.3.0/x86_64-linux/io/wait.so
7fb4680fc000-7fb468126000 r-xp 00000000 08:03 948454                     /usr/lib/ruby/2.3.0/x86_64-linux/socket.so
7fb468126000-7fb468325000 ---p 0002a000 08:03 948454                     /usr/lib/ruby/2.3.0/x86_64-linux/socket.so
7fb468325000-7fb468326000 r--p 00029000 08:03 948454                     /usr/lib/ruby/2.3.0/x86_64-linux/socket.so
7fb468326000-7fb468327000 rw-p 0002a000 08:03 948454                     /usr/lib/ruby/2.3.0/x86_64-linux/socket.so
7fb468327000-7fb46832d000 r-xp 00000000 08:03 948457                     /usr/lib/ruby/2.3.0/x86_64-linux/etc.so
7fb46832d000-7fb46852c000 ---p 00006000 08:03 948457                     /usr/lib/ruby/2.3.0/x86_64-linux/etc.so
7fb46852c000-7fb46852d000 r--p 00005000 08:03 948457                     /usr/lib/ruby/2.3.0/x86_64-linux/etc.so
7fb46852d000-7fb46852e000 rw-p 00006000 08:03 948457                     /usr/lib/ruby/2.3.0/x86_64-linux/etc.so
7fb46852e000-7fb468532000 r-xp 00000000 08:03 948522                     /usr/lib/ruby/2.3.0/x86_64-linux/io/console.so
7fb468532000-7fb468731000 ---p 00004000 08:03 948522                     /usr/lib/ruby/2.3.0/x86_64-linux/io/console.so
7fb468731000-7fb468732000 r--p 00003000 08:03 948522                     /usr/lib/ruby/2.3.0/x86_64-linux/io/console.so
7fb468732000-7fb468733000 rw-p 00004000 08:03 948522                     /usr/lib/ruby/2.3.0/x86_64-linux/io/console.so
7fb468733000-7fb468739000 r-xp 00000000 08:03 948472                     /usr/lib/ruby/2.3.0/x86_64-linux/pathname.so
7fb468739000-7fb468938000 ---p 00006000 08:03 948472                     /usr/lib/ruby/2.3.0/x86_64-linux/pathname.so
7fb468938000-7fb468939000 r--p 00005000 08:03 948472                     /usr/lib/ruby/2.3.0/x86_64-linux/pathname.so
7fb468939000-7fb46893a000 rw-p 00006000 08:03 948472                     /usr/lib/ruby/2.3.0/x86_64-linux/pathname.so
7fb46893a000-7fb468941000 r-xp 00000000 08:03 948455                     /usr/lib/ruby/2.3.0/x86_64-linux/stringio.so
7fb468941000-7fb468b40000 ---p 00007000 08:03 948455                     /usr/lib/ruby/2.3.0/x86_64-linux/stringio.so
7fb468b40000-7fb468b41000 r--p 00006000 08:03 948455                     /usr/lib/ruby/2.3.0/x86_64-linux/stringio.so
7fb468b41000-7fb468b42000 rw-p 00007000 08:03 948455                     /usr/lib/ruby/2.3.0/x86_64-linux/stringio.so
7fb468b42000-7fb468b44000 r-xp 00000000 08:03 1061025                    /usr/lib/ruby/2.3.0/x86_64-linux/enc/trans/transdb.so
7fb468b44000-7fb468d44000 ---p 00002000 08:03 1061025                    /usr/lib/ruby/2.3.0/x86_64-linux/enc/trans/transdb.so
7fb468d44000-7fb468d45000 r--p 00002000 08:03 1061025                    /usr/lib/ruby/2.3.0/x86_64-linux/enc/trans/transdb.so
7fb468d45000-7fb468d46000 rw-p 00003000 08:03 1061025                    /usr/lib/ruby/2.3.0/x86_64-linux/enc/trans/transdb.so
7fb468d46000-7fb468d48000 r-xp 00000000 08:03 948512                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/encdb.so
7fb468d48000-7fb468f47000 ---p 00002000 08:03 948512                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/encdb.so
7fb468f47000-7fb468f48000 r--p 00001000 08:03 948512                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/encdb.so
7fb468f48000-7fb468f49000 rw-p 00002000 08:03 948512                     /usr/lib/ruby/2.3.0/x86_64-linux/enc/encdb.so
7fb468f49000-7fb46904a000 rw-p 00000000 00:00 0 
7fb46904a000-7fb46914d000 r-xp 00000000 08:03 935421                     /usr/lib/libm-2.24.so
7fb46914d000-7fb46934c000 ---p 00103000 08:03 935421                     /usr/lib/libm-2.24.so
7fb46934c000-7fb46934d000 r--p 00102000 08:03 935421                     /usr/lib/libm-2.24.so
7fb46934d000-7fb46934e000 rw-p 00103000 08:03 935421                     /usr/lib/libm-2.24.so
7fb46934e000-7fb469356000 r-xp 00000000 08:03 935412                     /usr/lib/libcrypt-2.24.so
7fb469356000-7fb469556000 ---p 00008000 08:03 935412                     /usr/lib/libcrypt-2.24.so
7fb469556000-7fb469557000 r--p 00008000 08:03 935412                     /usr/lib/libcrypt-2.24.so
7fb469557000-7fb469558000 rw-p 00009000 08:03 935412                     /usr/lib/libcrypt-2.24.so
7fb469558000-7fb469586000 rw-p 00000000 00:00 0 
7fb469586000-7fb469588000 r-xp 00000000 08:03 935420                     /usr/lib/libdl-2.24.so
7fb469588000-7fb469788000 ---p 00002000 08:03 935420                     /usr/lib/libdl-2.24.so
7fb469788000-7fb469789000 r--p 00002000 08:03 935420                     /usr/lib/libdl-2.24.so
7fb469789000-7fb46978a000 rw-p 00003000 08:03 935420                     /usr/lib/libdl-2.24.so
7fb46978a000-7fb46981c000 r-xp 00000000 08:03 935607                     /usr/lib/libgmp.so.10.3.1
7fb46981c000-7fb469a1b000 ---p 00092000 08:03 935607                     /usr/lib/libgmp.so.10.3.1
7fb469a1b000-7fb469a1c000 r--p 00091000 08:03 935607                     /usr/lib/libgmp.so.10.3.1
7fb469a1c000-7fb469a1d000 rw-p 00092000 08:03 935607                     /usr/lib/libgmp.so.10.3.1
7fb469a1d000-7fb469a35000 r-xp 00000000 08:03 934933                     /usr/lib/libpthread-2.24.so
7fb469a35000-7fb469c34000 ---p 00018000 08:03 934933                     /usr/lib/libpthread-2.24.so
7fb469c34000-7fb469c35000 r--p 00017000 08:03 934933                     /usr/lib/libpthread-2.24.so
7fb469c35000-7fb469c36000 rw-p 00018000 08:03 934933                     /usr/lib/libpthread-2.24.so
7fb469c36000-7fb469c3a000 rw-p 00000000 00:00 0 
7fb469c3a000-7fb469dcf000 r-xp 00000000 08:03 934952                     /usr/lib/libc-2.24.so
7fb469dcf000-7fb469fce000 ---p 00195000 08:03 934952                     /usr/lib/libc-2.24.so
7fb469fce000-7fb469fd2000 r--p 00194000 08:03 934952                     /usr/lib/libc-2.24.so
7fb469fd2000-7fb469fd4000 rw-p 00198000 08:03 934952                     /usr/lib/libc-2.24.so
7fb469fd4000-7fb469fd8000 rw-p 00000000 00:00 0 
7fb469fd8000-7fb46a24c000 r-xp 00000000 08:03 936075                     /usr/lib/libruby.so.2.3.0
7fb46a24c000-7fb46a44b000 ---p 00274000 08:03 936075                     /usr/lib/libruby.so.2.3.0
7fb46a44b000-7fb46a451000 r--p 00273000 08:03 936075                     /usr/lib/libruby.so.2.3.0
7fb46a451000-7fb46a454000 rw-p 00279000 08:03 936075                     /usr/lib/libruby.so.2.3.0
7fb46a454000-7fb46a465000 rw-p 00000000 00:00 0 
7fb46a465000-7fb46a488000 r-xp 00000000 08:03 934951                     /usr/lib/ld-2.24.so
7fb46a4d6000-7fb46a66e000 r--p 00000000 08:03 934978                     /usr/lib/locale/locale-archive
7fb46a66e000-7fb46a674000 rw-p 00000000 00:00 0 
7fb46a681000-7fb46a683000 r--s 00000000 08:03 948907                     /usr/bin/ruby
7fb46a683000-7fb46a684000 ---p 00000000 00:00 0 
7fb46a684000-7fb46a687000 rw-p 00000000 00:00 0 
7fb46a687000-7fb46a688000 r--p 00022000 08:03 934951                     /usr/lib/ld-2.24.so
7fb46a688000-7fb46a689000 rw-p 00023000 08:03 934951                     /usr/lib/ld-2.24.so
7fb46a689000-7fb46a68a000 rw-p 00000000 00:00 0 
7ffecd510000-7ffecdd0f000 rw-p 00000000 00:00 0                          [stack]
7ffecdd45000-7ffecdd47000 r--p 00000000 00:00 0                          [vvar]
7ffecdd47000-7ffecdd49000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]


[NOTE]
You may have encountered a bug in the Ruby interpreter or extension libraries.
Bug reports are welcome.
For details: http://www.ruby-lang.org/bugreport.html

[1]    956 abort (core dumped)  bin/sandbox_extract crashes/nil_remove_to_s.mrb

GDB:

$ gdb attach 730
GNU gdb (GDB) 7.12
Copyright (C) 2016 Free Software Foundation, Inc.
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attach: No such file or directory.
Attaching to process 730
[New LWP 731]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
0x00007ffb3f9414b8 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
(gdb) c
Continuing.
[New Thread 0x7ffb3ab23700 (LWP 823)]

Thread 3 "ruby" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7ffb3ab23700 (LWP 823)]
mrb_any_to_s (mrb=0x7ffb3ab244e0, obj=...) at /home/simon/git/shopify/mruby-engine/ext/mruby_engine/mruby/src/object.c:443
443	  mrb_str_concat(mrb, str, mrb_ptr_to_str(mrb, mrb_cptr(obj)));
(gdb) bt
#0  mrb_any_to_s (mrb=0x7ffb3ab244e0, obj=...) at /home/simon/git/shopify/mruby-engine/ext/mruby_engine/mruby/src/object.c:443
#1  0x00007ffb3bfae952 in mrb_vm_exec (mrb=mrb@entry=0x7ffb3ab244e0, proc=<optimized out>, proc@entry=0x7ffb3ab2c130, pc=<optimized out>)
    at /home/simon/git/shopify/mruby-engine/ext/mruby_engine/mruby/src/vm.c:1165
#2  0x00007ffb3bfb4627 in mrb_vm_run (mrb=0x7ffb3ab244e0, proc=0x7ffb3ab2c130, self=..., stack_keep=stack_keep@entry=0)
    at /home/simon/git/shopify/mruby-engine/ext/mruby_engine/mruby/src/vm.c:766
#3  0x00007ffb3bf938c3 in mruby_engine_monitored_eval (data=0x7ffb3ab243e0) at ../../../../ext/mruby_engine/eval_monitored.c:68
#4  0x00007ffb3f93b454 in start_thread () from /usr/lib/libpthread.so.0
#5  0x00007ffb3fc397df in clone () from /usr/lib/libc.so.6
(gdb) info registers
rax            0x7ffb3ab2c100	140716998312192
rbx            0x7ffb3ab244e0	140716998280416
rcx            0x3a	58
rdx            0x110	272
rsi            0x7ffb3c023a2e	140717020297774
rdi            0x7ffb3ab65f3a	140716998549306
rbp            0x7ffb3ab2c100	0x7ffb3ab2c100
rsp            0x7ffb3ab22ab0	0x7ffb3ab22ab0
r8             0x3	3
r9             0x0	0
r10            0x262	610
r11            0x7ffb3bfa7d40	140717019790656
r12            0x0	0
r13            0x7ffb3ab2c0b8	140716998312120
r14            0x7ffb3ab244e0	140716998280416
r15            0x7ffb3ab2f220	140716998324768
rip            0x7ffb3bf9d787	0x7ffb3bf9d787 <mrb_any_to_s+103>
eflags         0x10206	[ PF IF RF ]
cs             0x33	51
ss             0x2b	43
ds             0x0	0
es             0x0	0
fs             0x0	0
gs             0x0	0
(gdb) quit
A debugging session is active.

	Inferior 1 [process 730] will be detached.

Quit anyway? (y or n) y
Detaching from program: /usr/bin/ruby, process 730

This report was disclosed publicly on HackerOne and belongs to its author and the program. See the original