1 files changed, 25 insertions, 0 deletions
diff --git a/test/bntest.c b/test/bntest.c
index e760c64f7f..d042a3e2ba 100644
--- a/test/bntest.c
+++ b/test/bntest.c
@@ -519,6 +519,31 @@ static int test_modexp_mont5(void)
     if (!TEST_BN_eq(c, d))
         goto err;
 
+    /*
+     * rsaz_1024_mul_avx2 expects fully-reduced inputs.
+     * BN_mod_exp_mont_consttime should reduce the input first.
+     */
+    BN_hex2bn(&a,
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF2020202020DF");
+    BN_hex2bn(&b,
+        "1FA53F26F8811C58BE0357897AA5E165693230BC9DF5F01DFA6A2D59229EC69D"
+        "9DE6A89C36E3B6957B22D6FAAD5A3C73AE587B710DBE92E83D3A9A3339A085CB"
+        "B58F508CA4F837924BB52CC1698B7FDC2FD74362456A595A5B58E38E38E38E38"
+        "E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E38E");
+    BN_hex2bn(&n,
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
+        "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF2020202020DF");
+    BN_MONT_CTX_set(mont, n, ctx);
+    BN_mod_exp_mont_consttime(c, a, b, n, ctx, mont);
+    BN_zero(d);
+    if (!TEST_BN_eq(c, d))
+        goto err;
+
     /* Zero input */
     BN_bntest_rand(p, 1024, 0, 0);
     BN_zero(a);