diff --git a/sshbn.c b/sshbn.c
index a5e0552f..b1ea5d63 100644
--- a/sshbn.c
+++ b/sshbn.c
@@ -1610,6 +1610,8 @@ Bignum bigdiv(Bignum a, Bignum b)
 {
     Bignum q = newbn(a[0]);
     bigdivmod(a, b, NULL, q);
+    while (q[0] > 1 && q[q[0]] == 0)
+        q[0]--;
     return q;
 }
 
@@ -1620,6 +1622,8 @@ Bignum bigmod(Bignum a, Bignum b)
 {
     Bignum r = newbn(b[0]);
     bigdivmod(a, b, r, NULL);
+    while (r[0] > 1 && r[r[0]] == 0)
+        r[0]--;
     return r;
 }
 
@@ -1679,6 +1683,8 @@ Bignum modinv(Bignum number, Bignum modulus)
 	bigdivmod(a, b, t, q);
 	while (t[0] > 1 && t[t[0]] == 0)
 	    t[0]--;
+	while (q[0] > 1 && q[q[0]] == 0)
+	    q[0]--;
 	freebn(a);
 	a = b;
 	b = t;