diff --git a/crypto/sm2/sm2_oct.c b/crypto/sm2/sm2_oct.c
index f9ca4cfb..0a006cce 100755
--- a/crypto/sm2/sm2_oct.c
+++ b/crypto/sm2/sm2_oct.c
@@ -272,6 +272,7 @@ SM2CiphertextValue *o2i_SM2CiphertextValue(const EC_GROUP *group,
 	/* set result */
 	*pin = p;
 	ret = cv;
+	cv = NULL;
 
 end:
 	if ((cv != *pout) && (!ret))