merge revision(s) 57119: [Backport #13052]

	array.c: check array length every time after yielding

	Since the Array may be modified during rb_yield(), the length before
	invoking the block can't be trusted. Fix possible out-of-bounds read in
	Array#combination and Array#repeated_combination.

	It may better to make a defensive copy of the Array, but for now let's
	follow what Array#permutation does.  [ruby-core:78738] [Bug #13052]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@57350 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 13 insertions, 6 deletions

diff --git a/array.c b/array.c
index 729de9c081..9649473f35 100644
--- a/array.c
+++ b/array.c
@@ -5063,7 +5063,7 @@ rb_ary_combination(VALUE ary, VALUE num)
 	rb_yield(rb_ary_new2(0));
     }
     else if (n == 1) {
-	for (i = 0; i < len; i++) {
+	for (i = 0; i < RARRAY_LEN(ary); i++) {
 	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
 	}
     }
@@ -5262,7 +5262,7 @@ rb_ary_repeated_combination(VALUE ary, VALUE num)
 	rb_yield(rb_ary_new2(0));
     }
     else if (n == 1) {
-	for (i = 0; i < len; i++) {
+	for (i = 0; i < RARRAY_LEN(ary); i++) {
 	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
 	}
     }
diff --git a/test/ruby/test_array.rb b/test/ruby/test_array.rb
index f27b8a5724..03e0b22223 100644
--- a/test/ruby/test_array.rb
+++ b/test/ruby/test_array.rb
@@ -2419,11 +2419,18 @@ class TestArray < Test::Unit::TestCase
 
   def test_combination_clear
     bug9939 = '[ruby-core:63149] [Bug #9939]'
-    assert_separately([], <<-'end;')
-      100_000.times {Array.new(1000)}
+    assert_nothing_raised(bug9939) {
       a = [*0..100]
       a.combination(3) {|*,x| a.clear}
-    end;
+    }
+
+    bug13052 = '[ruby-core:78738] [Bug #13052] Array#combination segfaults if the Array is modified during iteration'
+    assert_nothing_raised(bug13052) {
+      a = [*0..100]
+      a.combination(1) { a.clear }
+      a = [*0..100]
+      a.repeated_combination(1) { a.clear }
+    }
   end
 
   def test_product2
diff --git a/version.h b/version.h
index 832286d490..bdef6a33a5 100644
--- a/version.h
+++ b/version.h
@@ -1,6 +1,6 @@
 #define RUBY_VERSION "2.3.3"
 #define RUBY_RELEASE_DATE "2017-01-17"
-#define RUBY_PATCHLEVEL 234
+#define RUBY_PATCHLEVEL 235
 
 #define RUBY_RELEASE_YEAR 2017
 #define RUBY_RELEASE_MONTH 1