Fix memory leak.

src/core/tsi/ssl_transport_security_utils.cc

@@ -425,8 +425,8 @@ absl::StatusOr<EVP_PKEY*> ParsePemPrivateKey(
   }
   EVP_PKEY* pkey =
       PEM_read_bio_PrivateKey(in, /*x=*/nullptr, /*cb=*/nullptr, /*u=*/nullptr);
+  BIO_free(in);
   if (pkey == nullptr) {
-    BIO_free(in);
     return absl::NotFoundError("No private key found.");
   }
   return pkey;

test/core/tsi/ssl_transport_security_utils_test.cc

@@ -820,18 +820,21 @@ TEST(ParsePemPrivateKeyTest, RsaSuccess1) {
   absl::StatusOr<EVP_PKEY*> pkey = ParsePemPrivateKey(kPrivateKeyPem);
   EXPECT_EQ(pkey.status(), absl::OkStatus());
   EXPECT_NE(*pkey, nullptr);
+  EVP_PKEY_free(*pkey);
 }
 
 TEST(ParsePemPrivateKeyTest, RsaSuccess2) {
   absl::StatusOr<EVP_PKEY*> pkey = ParsePemPrivateKey(kRsaPrivateKeyPem);
   EXPECT_EQ(pkey.status(), absl::OkStatus());
   EXPECT_NE(*pkey, nullptr);
+  EVP_PKEY_free(*pkey);
 }
 
 TEST(ParsePemPrivateKeyTest, EcSuccess) {
   absl::StatusOr<EVP_PKEY*> pkey = ParsePemPrivateKey(kEcPrivateKeyPem);
   EXPECT_EQ(pkey.status(), absl::OkStatus());
   EXPECT_NE(*pkey, nullptr);
+  EVP_PKEY_free(*pkey);
 }
 }  // namespace testing
 }  // namespace grpc_core