Merge pull request #23670 from apolcyn/fix_segv

Fix ruby segfault on nil optional creds params

src/ruby/ext/grpc/rb_channel_credentials.c

@@ -165,6 +165,15 @@ static VALUE grpc_rb_channel_credentials_init(int argc, VALUE* argv,
   if (pem_private_key == Qnil && pem_cert_chain == Qnil) {
     creds = grpc_ssl_credentials_create(pem_root_certs_cstr, NULL, NULL, NULL);
   } else {
+    if (pem_private_key == Qnil) {
+      rb_raise(
+          rb_eRuntimeError,
+          "could not create a credentials because pem_private_key is NULL");
+    }
+    if (pem_cert_chain == Qnil) {
+      rb_raise(rb_eRuntimeError,
+               "could not create a credentials because pem_cert_chain is NULL");
+    }
     key_cert_pair.private_key = RSTRING_PTR(pem_private_key);
     key_cert_pair.cert_chain = RSTRING_PTR(pem_cert_chain);
     creds = grpc_ssl_credentials_create(pem_root_certs_cstr, &key_cert_pair,

src/ruby/spec/channel_credentials_spec.rb

@@ -50,6 +50,16 @@ describe GRPC::Core::ChannelCredentials do
       blk = proc { ChannelCredentials.new(nil) }
       expect(&blk).not_to raise_error
     end
+
+    it 'fails gracefully with constructed with a nil private key' do
+      blk = proc { GRPC::Core::ChannelCredentials.new(nil, nil, '') }
+      expect(&blk).to raise_error
+    end
+
+    it 'fails gracefully with constructed with a nil cert chain' do
+      blk = proc { GRPC::Core::ChannelCredentials.new(nil, '', nil) }
+      expect(&blk).to raise_error
+    end
   end
 
   describe '#compose' do