1 files changed, 9 insertions, 2 deletions

diff --git a/src/lib/libcrypto/ecdh/ech_lib.c b/src/lib/libcrypto/ecdh/ech_lib.c
index dadbfd3c49..0644431b75 100644
--- a/src/lib/libcrypto/ecdh/ech_lib.c
+++ b/src/lib/libcrypto/ecdh/ech_lib.c
@@ -222,8 +222,15 @@ ECDH_DATA *ecdh_check(EC_KEY *key)
                 ecdh_data = (ECDH_DATA *)ecdh_data_new();
                 if (ecdh_data == NULL)
                         return NULL;
-                EC_KEY_insert_key_method_data(key, (void *)ecdh_data,
-                        ecdh_data_dup, ecdh_data_free, ecdh_data_free);
+                data = EC_KEY_insert_key_method_data(key, (void *)ecdh_data,
+                           ecdh_data_dup, ecdh_data_free, ecdh_data_free);
+                if (data != NULL)
+                        {
+                        /* Another thread raced us to install the key_method
+                         * data and won. */
+                        ecdh_data_free(ecdh_data);
+                        ecdh_data = (ECDH_DATA *)data;
+                        }
         }
         else
                 ecdh_data = (ECDH_DATA *)data;