Commit 57a6ac7c authored by Ben Laurie's avatar Ben Laurie
Browse files

Check scalar->d before we use it (in BN_num_bits()). (Coverity ID 129)

parent 9b9cb004

crypto/ec/ec_mult.c

+6 −6
Original line number Diff line number Diff line
@@ -224,6 +224,12 @@ static signed char *compute_wNAF(const BIGNUM *scalar, int w, size_t *ret_len) 
		sign = -1;

		}



	if (scalar->d == NULL || scalar->top == 0)

		{

		ECerr(EC_F_COMPUTE_WNAF, ERR_R_INTERNAL_ERROR);

		goto err;

		}



	len = BN_num_bits(scalar);

	r = OPENSSL_malloc(len + 1); /* modified wNAF may be one digit longer than binary representation

	                              * (*ret_len will be set to the actual length, i.e. at most
@@ -233,12 +239,6 @@ static signed char *compute_wNAF(const BIGNUM *scalar, int w, size_t *ret_len) 
		ECerr(EC_F_COMPUTE_WNAF, ERR_R_MALLOC_FAILURE);

		goto err;

		}



	if (scalar->d == NULL || scalar->top == 0)

		{

		ECerr(EC_F_COMPUTE_WNAF, ERR_R_INTERNAL_ERROR);

		goto err;

		}

	window_val = scalar->d[0] & mask;

	j = 0;

	while ((window_val != 0) || (j + w + 1 < len)) /* if j+w+1 >= len, window_val will not increase */