rtlwifi: fix potential NULL pointer dereference

In case dev_alloc_skb fails, the fix safely returns to avoid
potential NULL pointer dereference.

Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/realtek/rtlwifi/rtl8188ee/fw.c

@@ -600,6 +600,8 @@ void rtl88e_set_fw_rsvdpagepkt(struct ieee80211_hw *hw, bool b_dl_finished)
 		      u1rsvdpageloc, 3);
 
 	skb = dev_alloc_skb(totalpacketlen);
+	if (!skb)
+		return;
 	skb_put_data(skb, &reserved_page_packet, totalpacketlen);
 
 	rtstatus = rtl_cmd_send_packet(hw, skb);

drivers/net/wireless/realtek/rtlwifi/rtl8192c/fw_common.c

@@ -623,6 +623,8 @@ void rtl92c_set_fw_rsvdpagepkt(struct ieee80211_hw *hw,
 		      u1rsvdpageloc, 3);
 
 	skb = dev_alloc_skb(totalpacketlen);
+	if (!skb)
+		return;
 	skb_put_data(skb, &reserved_page_packet, totalpacketlen);
 
 	if (cmd_send_packet)

drivers/net/wireless/realtek/rtlwifi/rtl8192ee/fw.c

@@ -744,6 +744,8 @@ void rtl92ee_set_fw_rsvdpagepkt(struct ieee80211_hw *hw, bool b_dl_finished)
 		      u1rsvdpageloc, 3);
 
 	skb = dev_alloc_skb(totalpacketlen);
+	if (!skb)
+		return;
 	skb_put_data(skb, &reserved_page_packet, totalpacketlen);
 
 	rtstatus = rtl_cmd_send_packet(hw, skb);

drivers/net/wireless/realtek/rtlwifi/rtl8723ae/fw.c

@@ -448,6 +448,8 @@ void rtl8723e_set_fw_rsvdpagepkt(struct ieee80211_hw *hw, bool b_dl_finished)
 		      u1rsvdpageloc, 3);
 
 	skb = dev_alloc_skb(totalpacketlen);
+	if (!skb)
+		return;
 	skb_put_data(skb, &reserved_page_packet, totalpacketlen);
 
 	rtstatus = rtl_cmd_send_packet(hw, skb);

drivers/net/wireless/realtek/rtlwifi/rtl8723be/fw.c

@@ -562,6 +562,8 @@ void rtl8723be_set_fw_rsvdpagepkt(struct ieee80211_hw *hw,
 		      u1rsvdpageloc, sizeof(u1rsvdpageloc));
 
 	skb = dev_alloc_skb(totalpacketlen);
+	if (!skb)
+		return;
 	skb_put_data(skb, &reserved_page_packet, totalpacketlen);
 
 	rtstatus = rtl_cmd_send_packet(hw, skb);

drivers/net/wireless/realtek/rtlwifi/rtl8821ae/fw.c

@@ -1623,6 +1623,8 @@ out:
 		      &reserved_page_packet_8812[0], totalpacketlen);
 
 	skb = dev_alloc_skb(totalpacketlen);
+	if (!skb)
+		return;
 	skb_put_data(skb, &reserved_page_packet_8812, totalpacketlen);
 
 	rtstatus = rtl_cmd_send_packet(hw, skb);
@@ -1759,6 +1761,8 @@ out:
 		      &reserved_page_packet_8821[0], totalpacketlen);
 
 	skb = dev_alloc_skb(totalpacketlen);
+	if (!skb)
+		return;
 	skb_put_data(skb, &reserved_page_packet_8821, totalpacketlen);
 
 	rtstatus = rtl_cmd_send_packet(hw, skb);