merge revision(s) 62992:

	pack.c: fix underflow

	* pack.c (pack_unpack_internal): get rid of underflow.
	  https://hackerone.com/reports/298246

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@63001 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 5 insertions, 2 deletions

diff --git a/pack.c b/pack.c
index 33bcb2b7d7..577deb5a82 100644
--- a/pack.c
+++ b/pack.c
@@ -1138,7 +1138,7 @@ pack_unpack_internal(VALUE str, VALUE fmt, int mode)
 	else if (ISDIGIT(*p)) {
 	    errno = 0;
 	    len = STRTOUL(p, (char**)&p, 10);
-	    if (errno) {
+	    if (len < 0 || errno) {
 		rb_raise(rb_eRangeError, "pack length too big");
 	    }
 	}
diff --git a/test/ruby/test_pack.rb b/test/ruby/test_pack.rb
index f5b3266803..ce2682ee59 100644
--- a/test/ruby/test_pack.rb
+++ b/test/ruby/test_pack.rb
@@ -548,6 +548,9 @@ class TestPack < Test::Unit::TestCase
     assert_equal([1, 2], "\x01\x00\x00\x02".unpack("C@3C"))
     assert_equal([nil], "\x00".unpack("@1C")) # is it OK?
     assert_raise(ArgumentError) { "\x00".unpack("@2C") }
+
+    pos = (1 << [nil].pack("p").bytesize * 8) - 100 # -100
+    assert_raise(RangeError) {"0123456789".unpack("@#{pos}C10")}
   end
 
   def test_pack_unpack_percent
diff --git a/version.h b/version.h
index 9395d65fae..d5cc9a6585 100644
--- a/version.h
+++ b/version.h
@@ -1,6 +1,6 @@
 #define RUBY_VERSION "2.4.4"
 #define RUBY_RELEASE_DATE "2018-03-28"
-#define RUBY_PATCHLEVEL 291
+#define RUBY_PATCHLEVEL 292
 
 #define RUBY_RELEASE_YEAR 2018
 #define RUBY_RELEASE_MONTH 3