net: lwm2m: json: Check for int64_t overflow when parsing integer (d9395d85) · Commits · Wenxi XU / zephyr

subsys/net/lib/lwm2m/lwm2m_rw_json.c

+7 −5

Original line number	Diff line number	Diff line
		@@ -640,13 +640,14 @@ static int read_int(struct lwm2m_input_context in, int64_t value,
		bool accept_sign)
		{
		struct json_in_formatter_data *fd;
		uint64_t temp;
		uint8_t *buf;
		int i = 0;
		bool neg = false;
		char c;

		/* initialize values to 0 */
		*value = 0;
		temp = 0;

		fd = engine_get_in_user_data(in);
		if (!fd \|\| (fd->object_bit_field & JSON_V_TYPE) == 0) {
		@@ -663,7 +664,10 @@ static int read_int(struct lwm2m_input_context in, int64_t value,
		if (c == '-' && accept_sign && i == 0) {
		neg = true;
		} else if (isdigit(c) != 0) {
		value = value * 10 + (c - '0');
		temp = temp * 10ULL + (c - '0');
		if (temp > ((uint64_t)INT64_MAX + (neg ? 1ULL : 0ULL))) {
		return -EINVAL;
		}
		} else {
		/* anything else stop reading */
		break;
		@@ -671,9 +675,7 @@ static int read_int(struct lwm2m_input_context in, int64_t value,
		i++;
		}

		if (neg) {
		value = -value;
		}
		*value = neg ? -temp : temp;

		return i;
		}