mwifiex: correctly handling kzalloc

Since kzalloc can be failed in memory pressure,
it needs to be handled, otherwise NULL dereference could be happened

Signed-off-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/marvell/mwifiex/sdio.c

@@ -2053,8 +2053,19 @@ static int mwifiex_init_sdio(struct mwifiex_adapter *adapter)
 	/* Allocate skb pointer buffers */
 	card->mpa_rx.skb_arr = kzalloc((sizeof(void *)) *
 				       card->mp_agg_pkt_limit, GFP_KERNEL);
+	if (!card->mpa_rx.skb_arr) {
+		kfree(card->mp_regs);
+		return -ENOMEM;
+	}
+
 	card->mpa_rx.len_arr = kzalloc(sizeof(*card->mpa_rx.len_arr) *
 				       card->mp_agg_pkt_limit, GFP_KERNEL);
+	if (!card->mpa_rx.len_arr) {
+		kfree(card->mp_regs);
+		kfree(card->mpa_rx.skb_arr);
+		return -ENOMEM;
+	}
+
 	ret = mwifiex_alloc_sdio_mpa_buffers(adapter,
 					     card->mp_tx_agg_buf_size,
 					     card->mp_rx_agg_buf_size);