[PATCH 5.17 0475/1126] rtw88: check for validity before using a pointer

Greg Kroah-Hartman
2022-04-05T08:02:16Z

From: Muhammad Usama Anjum <usama.anjum@collabora.com>

[ Upstream commit a12f809968dbf46ce2a6bc94463db8d431bb75fc ]

ieee80211_probereq_get() can return NULL. Pointer skb should be checked
for validty before use. If it is not valid, list of skbs needs to be
freed.

Fixes: 10d162b2ed39 ("rtw88: 8822c: add ieee80211_ops::hw_scan")
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220121070813.9656-2-pkshih@realtek.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/realtek/rtw88/fw.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/net/wireless/realtek/rtw88/fw.c b/drivers/net/wireless/realtek/rtw88/fw.c
index 2f7c036f9022..b56dc43229d2 100644
--- a/drivers/net/wireless/realtek/rtw88/fw.c
+++ b/drivers/net/wireless/realtek/rtw88/fw.c
@@ -1866,11 +1866,19 @@ static int rtw_hw_scan_update_probe_req(struct rtw_dev *rtwdev,
req->ssids[i].ssid,
req->ssids[i].ssid_len,
req->ie_len);
+ if (!skb)
+ goto out;
rtw_append_probe_req_ie(rtwdev, skb, &list, rtwvif);
kfree_skb(skb);
}

return _rtw_hw_scan_update_probe_req(rtwdev, num, &list);
+
+out:
+ skb_queue_walk(&list, skb)
+ kfree_skb(skb);
+
+ return -ENOMEM;
}

static int rtw_add_chan_info(struct rtw_dev *rtwdev, struct rtw_chan_info *info,
--
2.34.1