ath11k: Replace zero-length arrays with flexible-array members

There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/78
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20220216194836.GA904035@embeddedor

drivers/net/wireless/ath/ath11k/ce.h

@@ -145,7 +145,7 @@ struct ath11k_ce_ring {
 	u32 hal_ring_id;
 
 	/* keep last */
-	struct sk_buff *skb[0];
+	struct sk_buff *skb[];
 };
 
 struct ath11k_ce_pipe {

drivers/net/wireless/ath/ath11k/core.h

@@ -815,7 +815,7 @@ struct ath11k_base {
 	} id;
 
 	/* must be last */
-	u8 drv_priv[0] __aligned(sizeof(void *));
+	u8 drv_priv[] __aligned(sizeof(void *));
 };
 
 struct ath11k_fw_stats_pdev {

drivers/net/wireless/ath/ath11k/dp.h

@@ -1173,12 +1173,12 @@ struct ath11k_htt_ppdu_stats_msg {
 	u32 ppdu_id;
 	u32 timestamp;
 	u32 rsvd;
-	u8 data[0];
+	u8 data[];
 } __packed;
 
 struct htt_tlv {
 	u32 header;
-	u8 value[0];
+	u8 value[];
 } __packed;
 
 #define HTT_TLV_TAG			GENMASK(11, 0)
@@ -1365,7 +1365,7 @@ struct htt_ppdu_stats_usr_cmn_array {
 	 * tx_ppdu_stats_info is variable length, with length =
 	 *     number_of_ppdu_stats * sizeof (struct htt_tx_ppdu_stats_info)
 	 */
-	struct htt_tx_ppdu_stats_info tx_ppdu_info[0];
+	struct htt_tx_ppdu_stats_info tx_ppdu_info[];
 } __packed;
 
 struct htt_ppdu_user_stats {
@@ -1427,7 +1427,7 @@ struct htt_ppdu_stats_info {
  */
 struct htt_pktlog_msg {
 	u32 hdr;
-	u8 payload[0];
+	u8 payload[];
 };
 
 /**
@@ -1648,7 +1648,7 @@ struct ath11k_htt_extd_stats_msg {
 	u32 info0;
 	u64 cookie;
 	u32 info1;
-	u8 data[0];
+	u8 data[];
 } __packed;
 
 #define	HTT_MAC_ADDR_L32_0	GENMASK(7, 0)

drivers/net/wireless/ath/ath11k/rx_desc.h

@@ -1445,7 +1445,7 @@ struct hal_rx_desc_ipq8074 {
 	__le32 hdr_status_tag;
 	__le32 phy_ppdu_id;
 	u8 hdr_status[HAL_RX_DESC_HDR_STATUS_LEN];
-	u8 msdu_payload[0];
+	u8 msdu_payload[];
 } __packed;
 
 struct hal_rx_desc_qcn9074 {
@@ -1464,7 +1464,7 @@ struct hal_rx_desc_qcn9074 {
 	__le32 hdr_status_tag;
 	__le32 phy_ppdu_id;
 	u8 hdr_status[HAL_RX_DESC_HDR_STATUS_LEN];
-	u8 msdu_payload[0];
+	u8 msdu_payload[];
 } __packed;
 
 struct hal_rx_desc_wcn6855 {
@@ -1483,7 +1483,7 @@ struct hal_rx_desc_wcn6855 {
 	__le32 hdr_status_tag;
 	__le32 phy_ppdu_id;
 	u8 hdr_status[HAL_RX_DESC_HDR_STATUS_LEN];
-	u8 msdu_payload[0];
+	u8 msdu_payload[];
 } __packed;
 
 struct hal_rx_desc {

drivers/net/wireless/ath/ath11k/spectral.c

@@ -107,7 +107,7 @@ struct spectral_search_fft_report {
 	__le32 info1;
 	__le32 info2;
 	__le32 reserve0;
-	u8 bins[0];
+	u8 bins[];
 } __packed;
 
 struct ath11k_spectral_search_report {