[PATCH 2/6] rtw89: fix null vif pointer when hw_scan fails

[Ping-Ke Shih <pkshih@realtek.com>]

From: Po Hao Huang <phhuang@realtek.com>

Add this check to avoid crash by dereferencing a null pointer. When hwscan
fails due to no memory or dma failure, the scan flag in ieee80211_local is
cleared. So mac80211 determine that it's not hw_scan then calls
sw_scan_complete() with null vif, which is also freed during the fail.

Signed-off-by: Po Hao Huang <phhuang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
---
 drivers/net/wireless/realtek/rtw89/core.c | 5 ++++-
 drivers/net/wireless/realtek/rtw89/fw.c   | 4 ++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw89/core.c b/drivers/net/wireless/realtek/rtw89/core.c
index e24e133a94df6..958fe2787c6a1 100644
--- a/drivers/net/wireless/realtek/rtw89/core.c
+++ b/drivers/net/wireless/realtek/rtw89/core.c
@@ -2875,7 +2875,10 @@ void rtw89_core_scan_start(struct rtw89_dev *rtwdev, struct rtw89_vif *rtwvif,
 void rtw89_core_scan_complete(struct rtw89_dev *rtwdev,
 			      struct ieee80211_vif *vif, bool hw_scan)
 {
-	struct rtw89_vif *rtwvif = (struct rtw89_vif *)vif->drv_priv;
+	struct rtw89_vif *rtwvif = vif ? (struct rtw89_vif *)vif->drv_priv : NULL;
+
+	if (!rtwvif)
+		return;
 
 	ether_addr_copy(rtwvif->mac_addr, vif->addr);
 	rtw89_fw_h2c_cam(rtwdev, rtwvif, NULL, NULL);
diff --git a/drivers/net/wireless/realtek/rtw89/fw.c b/drivers/net/wireless/realtek/rtw89/fw.c
index 7fb4509a6c72a..2d9c3157d878c 100644
--- a/drivers/net/wireless/realtek/rtw89/fw.c
+++ b/drivers/net/wireless/realtek/rtw89/fw.c
@@ -2257,7 +2257,7 @@ static int rtw89_hw_scan_add_chan_list(struct rtw89_dev *rtwdev,
 		list_add_tail(&ch_info->list, &chan_list);
 		off_chan_time += ch_info->period;
 	}
-	rtw89_fw_h2c_scan_list_offload(rtwdev, list_len, &chan_list);
+	ret = rtw89_fw_h2c_scan_list_offload(rtwdev, list_len, &chan_list);
 
 out:
 	list_for_each_entry_safe(ch_info, tmp, &chan_list, list) {
@@ -2368,7 +2368,7 @@ int rtw89_hw_scan_offload(struct rtw89_dev *rtwdev, struct ieee80211_vif *vif,
 		if (ret)
 			goto out;
 	}
-	rtw89_fw_h2c_scan_offload(rtwdev, &opt, rtwvif);
+	ret = rtw89_fw_h2c_scan_offload(rtwdev, &opt, rtwvif);
 out:
 	return ret;
 }
-- 
2.25.1