Language: C
Label: vulnerable
CWE: CWE-190 \u2014 Integer Overflow or Wraparound
The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control.

Code:
int cp_cmlhs_onv(const g1_t r, const g2_t s, const g1_t sig[], const g2_t z[],
		const g1_t a[], const g1_t c[], const bn_t msg, const char *data,
		const g1_t h, const gt_t vk, const g2_t y[], const g2_t pk[],
		size_t slen, int bls) {
	g1_t g1;
	g2_t g2;
	gt_t e, u, v;
	bn_t k, n;
	int len, dlen = strlen(data), result = 1;
	uint8_t *buf = RLC_ALLOCA(uint8_t, 1 + 8 * RLC_FP_BYTES + dlen);

	g1_null(g1);
	g2_null(g2);
	gt_null(e);
	gt_null(u);
	gt_null(v);
	bn_null(k);
	bn_null(n);

	RLC_TRY {
		g1_new(g1);
		g2_new(g2);
		gt_new(e);
		gt_new(u);
		gt_new(v);
		bn_new(k);
		bn_new(n);
		if (buf == NULL) {
			RLC_THROW(ERR_NO_MEMORY);
		}

		for (int i = 0; i < slen; i++) {
			len = g2_size_bin(z[i], 0);
			g2_write_bin(buf, len, z[i], 0);
			memcpy(buf + len, data, dlen);
			if (bls) {
				result &= cp_bls_ver(sig[i], buf, len + dlen, pk[i]);
			} else {
				fp_prime_back(k, sig[i]->x);
				fp_prime_back(n, sig[i]->y);
				fp_copy(g1->x, pk[i]->x[0]);
				fp_copy(g1->y, pk[i]->y[0]);
				fp_set_dig(g1->z, 1);
				result &= cp_ecdsa_ver(k, n, buf, len + dlen, 0, g1);
			}
		}

		pc_get_ord(n);
		g1_get_gen(g1);
		g2_get_gen(g2);

		pc_map_sim(e, a, z, slen);
		pc_map_sim(u, c, y, slen);
		pc_map(v, r, g2);
		gt_mul(u, u, v);
		gt_mul(u, u, vk);

		if (gt_cmp(e, u) != RLC_EQ) {
			result = 0;
		}

		pc_map(e, g1, s);
		g1_set_infty(g1);
		for (int i = 0; i < slen; i++) {
			g1_add(g1, g1, c[i]);
		}
		g1_norm(g1, g1);
		pc_map(u, g1, g2);
		gt_mul(e, e, u);

		g1_mul(g1, h, msg);
		pc_map(v, g1, g2);
		if (gt_cmp(e, v) != RLC_EQ) {
			result = 0;
		}
	} RLC_CATCH_ANY {
		RLC_THROW(ERR_CAUGHT);
	} RLC_FINALLY {
		g1_free(g1);
		g2_free(g2);
		gt_free(e);
		gt_free(u);
		gt_free(v);
		bn_free(k);
		bn_free(n);
		RLC_FREE(buf);
	}
	return result;
}