diff --git a/crypto/ec/asm/ecp_sm2p256-riscv64.pl b/crypto/ec/asm/ecp_sm2p256-riscv64.pl
index 0fb1675302..2a17e124dc 100644
--- a/crypto/ec/asm/ecp_sm2p256-riscv64.pl
+++ b/crypto/ec/asm/ecp_sm2p256-riscv64.pl
@@ -881,6 +881,7 @@ $code.=<<___;
 	add $t1, $t1, $s6
 	sltu $c2, $t1, $s6
 	add $t1, $t1, $c1
+	sltu $c1, $t1, $c1
 	add $c1, $c1, $c2
 	add $t2, $t2, $c1
 	sltu $c1, $t2, $c1