diff --git a/ext/pg_text_encoder.c b/ext/pg_text_encoder.c
index e465a15d2..826e85728 100644
--- a/ext/pg_text_encoder.c
+++ b/ext/pg_text_encoder.c
@@ -430,9 +430,14 @@ pg_text_enc_bytea(t_pg_coder *conv, VALUE value, char *out, VALUE *intermediate,
 		}
 		return (int)(optr - out);
 	}else{
+		long size;
 		*intermediate = rb_obj_as_string(value);
+		size = RSTRING_LEN(*intermediate);
+
 		/* The output starts with "\x" and each character is converted to hex. */
-		return 2 + RSTRING_LENINT(*intermediate) * 2;
+		if( size > INT_MAX / 2 - 2 )
+			rb_raise( rb_eArgError, "too large input string for PG::TextEncoder::Bytea: %ld", size );
+		return 2 + size * 2;
 	}
 }
 
diff --git a/spec/pg/type_spec.rb b/spec/pg/type_spec.rb
index ad5e5f9b0..c69e35215 100644
--- a/spec/pg/type_spec.rb
+++ b/spec/pg/type_spec.rb
@@ -392,6 +392,15 @@ def textdec_timestamptz_decode_should_fail(str)
 				expect( textenc_bytea.encode("\x00\x01\x02\x03\xef".b) ).to eq( "\\x00010203ef" )
 			end
 
+			it "should raise too large string to bytea" do
+				n = 1_073_741_822
+				data = "A".b * n
+				enc = PG::TextEncoder::ToBase64.new(
+					elements_type: PG::TextEncoder::Bytea.new
+				)
+				expect{ enc.encode(data) }.to raise_error(ArgumentError, /too large input string/)
+			end
+
 			context 'text timestamps' do
 				it 'encodes timestamps without timezone' do
 					expect( textenc_timestamp.encode(Time.new(2016,1,2, 23, 23, 59.123456, 3*60*60)) ).