Subject: [PATCH AUTOSEL 4.19 028/205] wil6210: fix invalid memory access for rx_buff_mgmt debugfs

From: Sasha Levin <[email-masked]>
Date: Fri, 8 Nov 2019 06:34:55 -0500

From: Dedy Lansky <[email-masked]>

[ Upstream commit 4405b632e3da839defec966e4b0be44d0c5e3102 ]

Check rx_buff_mgmt is allocated before accessing its internal fields.

Signed-off-by: Dedy Lansky <[email-masked]>
Signed-off-by: Maya Erez <[email-masked]>
Signed-off-by: Kalle Valo <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/wireless/ath/wil6210/debugfs.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/wireless/ath/wil6210/debugfs.c b/drivers/net/wireless/ath/wil6210/debugfs.c
index 51c3330bc316f..ceace95b1595c 100644
--- a/drivers/net/wireless/ath/wil6210/debugfs.c
+++ b/drivers/net/wireless/ath/wil6210/debugfs.c
@@ -1263,6 +1263,9 @@ static int wil_rx_buff_mgmt_debugfs_show(struct seq_file *s, void *data)
 	int num_active;
 	int num_free;
 
+	if (!rbm->buff_arr)
+		return -EINVAL;
+
 	seq_printf(s, "  size = %zu\n", rbm->size);
 	seq_printf(s, "  free_list_empty_cnt = %lu\n",
 		   rbm->free_list_empty_cnt);
-- 
2.20.1