[#58730] [ruby-trunk - misc #9188][Open] r43870 make benchmark/bm_so_k_nucleotide.rb slow — "authorNari (Narihiro Nakamura)" <authorNari@...>

17 messages 2013/12/01

[#58732] [ruby-trunk - Bug #9189][Open] Build failure on Windows in case of nonascii TEMP environment. — "phasis68 (Heesob Park)" <phasis@...>

11 messages 2013/12/01

[#58750] [ruby-trunk - Feature #9190][Open] Expose serial helper macros — "simeonwillbanks (Simeon Willbanks)" <sfw@...>

13 messages 2013/12/01

[#58756] [ruby-trunk - Bug #9192][Open] Inconsistent comparison between Float and BigDecimal — "vatsu (Gustavo Sales)" <vatsu21@...>

18 messages 2013/12/02

[#58797] [ruby-trunk - Bug #9198][Open] Segfault in TestException#test_machine_stackoverflow — "vo.x (Vit Ondruch)" <v.ondruch@...>

11 messages 2013/12/02

[#58833] [ruby-trunk - Bug #9205][Open] Assertion failed: heap_pages_deferred_final == 0 — "phasis68 (Heesob Park)" <phasis@...>

11 messages 2013/12/03

[#58866] [ruby-trunk - misc #9215][Open] Maintenance Policy for Future Releases (2.1.0 & beyond) — "hone (Terence Lee)" <hone02@...>

17 messages 2013/12/05

[#58876] [ruby-trunk - Bug #9221][Open] Time.parse performance becomes exponentially worse as string length grows — "mpelzsherman (Michael Pelz-Sherman)" <mpelzsherman@...>

15 messages 2013/12/05

[#58948] [ruby-trunk - Bug #9226][Open] Getting method `inspect' called on unexpected T_NODE object (0x000000025ddea8 flags=0x109089c klass=0x0) (NotImplementedError) from Hash#inspect — "myronmarston (Myron Marston)" <myron.marston@...>

11 messages 2013/12/07

[#59032] [ruby-trunk - Bug #9239][Open] Array#to_h ignores flat arrays — "sawa (Tsuyoshi Sawada)" <sawadatsuyoshi@...>

15 messages 2013/12/10

[#59122] [ruby-trunk - Bug #9251][Open] ! operator has lower precedence than = in an assignment expression — "rits (First Last)" <redmine@...>

26 messages 2013/12/15

[#59198] [ruby-trunk - Bug #9262][Open] global_method_cache should be configurable or grow automatically — "tmm1 (Aman Gupta)" <ruby@...1.net>

28 messages 2013/12/19

[#59209] [ruby-trunk - Bug #9264][Open] Compiling error: encdb.bundle Undefined symbols for architecture x86_64 — "spastorino (Santiago Pastorino)" <santiago@...>

15 messages 2013/12/19
[#59211] [ruby-trunk - Bug #9264][Feedback] Compiling error: encdb.bundle Undefined symbols for architecture x86_64 — "zzak (Zachary Scott)" <e@...> 2013/12/19

[#59212] Re: [ruby-trunk - Bug #9264][Feedback] Compiling error: encdb.bundle Undefined symbols for architecture x86_64 — Santiago Pastorino <spastorino@...> 2013/12/19

zzak, make distclean is the first thing I've ran. Read the gist again :),

[#59213] Re: [ruby-trunk - Bug #9264][Feedback] Compiling error: encdb.bundle Undefined symbols for architecture x86_64 — Zachary Scott <e@...> 2013/12/19

Sorry I missed the gist, can you try building outside of $srcdir?

[#59214] Re: [ruby-trunk - Bug #9264][Feedback] Compiling error: encdb.bundle Undefined symbols for architecture x86_64 — Santiago Pastorino <spastorino@...> 2013/12/19

It works if I do ...

[#59215] Re: [ruby-trunk - Bug #9264][Feedback] Compiling error: encdb.bundle Undefined symbols for architecture x86_64 — Zachary Scott <e@...> 2013/12/19

I've been using the following:

[#59255] [ruby-trunk - Bug #9276][Open] "RUBY_FREE_MIN is obsolete. Use RUBY_GC_HEAP_FREE_SLOTS instead" warning should not be issued when both ENV vars are set. — "myronmarston (Myron Marston)" <myron.marston@...>

10 messages 2013/12/21

[#59260] [ruby-trunk - Feature #9278][Open] Magic comment "immutable: string" makes "literal".freeze the default for that file — "colindkelley (Colin Kelley)" <colin@...>

12 messages 2013/12/22

[#59343] [ruby-trunk - Bug #9309][Open] Crash while running tests — "mdemare (Michiel de MAre)" <merloen@...>

12 messages 2013/12/27

[#59345] [ruby-trunk - Bug #9310][Open] inheritance.rb: 27: [BUG] Segmentation fault at 0x00000c — "jasnow (Al Snow)" <jasnow@...>

10 messages 2013/12/27

[#59349] [ruby-trunk - Bug #9312][Open] Build the ruby executable in bin/ — "postmodern (Hal Brodigan)" <postmodern.mod3@...>

13 messages 2013/12/28

[#59365] [ruby-trunk - Bug #9316][Open] BigDecimal division in Ruby 2.1 — "abernardes (Andre Oliveira)" <abernardes@...>

15 messages 2013/12/28

[#59398] [ruby-trunk - Bug #9321][Open] rb_mod_const_missing does not generate a c-return event — "drkaes (Stefan Kaes)" <stkaes@...>

41 messages 2013/12/30

[#59429] [ruby-trunk - Feature #9330][Open] [PATCH 0/3] avoid redundant fcntl/fstat syscalls for cloexec sockets — "normalperson (Eric Wong)" <normalperson@...>

10 messages 2013/12/31

[ruby-core:58990] [ruby-trunk - Feature #8977] String#frozen that takes advantage of the deduping

From: "ko1 (Koichi Sasada)" <redmine@...>
Date: 2013-12-09 06:35:21 UTC
List: ruby-core #58990
Issue #8977 has been updated by ko1 (Koichi Sasada).


Now, I have one concern about security concern.

This kind of method can be used widely and easily.

And if this method is used with external string getting from IO,
fstring table can be grow and grow easily.

I'm afraid about such kind of security risk:
(1) DoS attack
(2) Side channel attack (observe from outside)

But I'm not a security expert. So I want to ask experts.

Note that this problem has not impact than Symbol related DoS attack
because these keys are collected.

-----

I think multiple tables support solve kind of issues.

To solve such issue (and continue to discuss this issue to 2.2),
Ruby level implementation and gem is reasonable alternative, I believe.

However, in ruby-level, we can't do that same thing.

Therefor nobu made a patch for WeakHash, a variant of WeakMap (we will make another ticket for it).

WeakMap is object_id -> Object map.
WeakHash is Object -> Object map.

With this class, we can make fstring technique
with multiple tables easily.

class FrozenStringTable
  def initialize
    @table = {} # WeakHash.new
  end

  def get str
    raise TypeError unless str.kind_of?(String)

    unless @table.has_key? str
      str.freeze
      @table[str] = str
    end
    @table[str]
  end
end

F1 = FrozenStringTable.new
p F1.get('foo').object_id #=> 8274120
p F1.get('foo').object_id #=> 8274120

----

In this comment, I show (1) security concern, and (2) alternative approach.


----------------------------------------
Feature #8977: String#frozen that takes advantage of the deduping 
https://bugs.ruby-lang.org/issues/8977#change-43544

Author: sam.saffron (Sam Saffron)
Status: Assigned
Priority: Normal
Assignee: matz (Yukihiro Matsumoto)
Category: 
Target version: current: 2.1.0


During memory profiling I noticed that a large amount of string duplication is generated from non pre-determined strings.

Take this report for example https://gist.github.com/SamSaffron/6789005 (generated using the memory_profiler gem that works against head) 

">=" x 4953
    /Users/sam/.rbenv/versions/2.1.0-dev/lib/ruby/2.1.0/rubygems/requirement.rb:93 x 4535

This string is most likely extracted from a version. 

Or 

"/Users/sam/.rbenv/versions/2.1.0-dev/lib/ruby/gems" x 5808
    /Users/sam/.rbenv/versions/2.1.0-dev/lib/ruby/gems/2.1.0/gems/activesupport-3.2.12/lib/active_support/dependencies.rb:251 x 3894

A string that can not be pre-determined. 

---- 


It would be nice to have 

"hello,world".split(",")[0].frozen.object_id == "hello"f.object_id 

Adding #frozen will give library builders a way of using the de-duping. It also could be implemented using weak refs in 2.0 and stubbed with a .dup.freeze in 1.9.3 . 

Thoughts ?  





-- 
http://bugs.ruby-lang.org/

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