Make sure BN_sqr can never return a negative value.

PR#3410
(cherry picked from commit e14e764c0d5d469da63d0819c6ffc0e1e9e7f0bb)

diff --git a/crypto/bn/bn_sqr.c b/crypto/bn/bn_sqr.c
index 270d0cd348b90056f14ce429676b700cd577118b..65bbf165d0e2f3bc3de3d662c1c02800dbb33c70 100644 (file)
--- a/crypto/bn/bn_sqr.c
+++ b/crypto/bn/bn_sqr.c
@@ -77,6 +77,7 @@ int BN_sqr(BIGNUM *r, const BIGNUM *a, BN_CTX *ctx)
        if (al <= 0)
                {
                r->top=0;
+               r->neg = 0;
                return 1;
                }