ext/openssl/ossl_bn.c (ossl_bn_initialize): get rid of SEGV

OpenSSL::BN.new(nil, 2) dumped core.

[ruby-core:92231] [Bug #15760]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67497 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/openssl/ossl_bn.c

@@ -187,6 +187,7 @@ ossl_bn_initialize(int argc, VALUE *argv, VALUE self)
     BIGNUM *bn;
     VALUE str, bs;
     int base = 10;
+    char *ptr;
 
     if (rb_scan_args(argc, argv, "11", &str, &bs) == 2) {
 	base = NUM2INT(bs);
@@ -213,12 +214,14 @@ ossl_bn_initialize(int argc, VALUE *argv, VALUE self)
     GetBN(self, bn);
     switch (base) {
     case 0:
-	if (!BN_mpi2bn((unsigned char *)StringValuePtr(str), RSTRING_LENINT(str), bn)) {
+        ptr = StringValuePtr(str);
+	if (!BN_mpi2bn((unsigned char *)ptr, RSTRING_LENINT(str), bn)) {
 	    ossl_raise(eBNError, NULL);
 	}
 	break;
     case 2:
-	if (!BN_bin2bn((unsigned char *)StringValuePtr(str), RSTRING_LENINT(str), bn)) {
+        ptr = StringValuePtr(str);
+	if (!BN_bin2bn((unsigned char *)ptr, RSTRING_LENINT(str), bn)) {
 	    ossl_raise(eBNError, NULL);
 	}
 	break;

test/openssl/test_bn.rb

@@ -272,6 +272,11 @@ class OpenSSL::TestBN < OpenSSL::TestCase
     assert_equal(0, @e1.ucmp(-999))
     assert_instance_of(String, @e1.hash.to_s)
   end
+
+  def test_type_error
+    bug15760 = '[ruby-core:92231] [Bug #15760]'
+    assert_raise(TypeError, bug15760) { OpenSSL::BN.new(nil, 2) }
+  end
 end
 
 end