[PATCH V2] iwlwifi: dvm: use struct_size over open coded arithmetic

From: "Minghao Chi (CGEL ZTE)" <redacted>

Replace zero-length array with flexible-array member and make use
of the struct_size() helper in kmalloc(). For example:

struct iwl_wipan_noa_data {
    ...
    u8 data[];
};

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.

Reported-by: Zeal Robot <redacted>
Signed-off-by: Minghao Chi (CGEL ZTE) <redacted>
---
 drivers/net/wireless/intel/iwlwifi/dvm/rx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/dvm/rx.c b/drivers/net/wireless/intel/iwlwifi/dvm/rx.c
index db0c41bbeb0e..bc6ed2f712f9 100644
--- a/drivers/net/wireless/intel/iwlwifi/dvm/rx.c
+++ b/drivers/net/wireless/intel/iwlwifi/dvm/rx.c

@@ -915,7 +915,7 @@ static void iwlagn_rx_noa_notification(struct iwl_priv *priv,
 		len += 1 + 2;
 		copylen += 1 + 2;
 
-		new_data = kmalloc(sizeof(*new_data) + len, GFP_ATOMIC);
+		new_data = kmalloc(struct_size(new_data, data, len), GFP_ATOMIC);
 		if (new_data) {
 			new_data->length = len;
 			new_data->data[0] = WLAN_EID_VENDOR_SPECIFIC;

-- 
2.25.1