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

From: Sasha Levin
Date: Fri Nov 08 2019 - 06:38:34 EST


From: Dedy Lansky <dlansky@xxxxxxxxxxxxxx>

[ Upstream commit 4405b632e3da839defec966e4b0be44d0c5e3102 ]

Check rx_buff_mgmt is allocated before accessing its internal fields.

Signed-off-by: Dedy Lansky <dlansky@xxxxxxxxxxxxxx>
Signed-off-by: Maya Erez <merez@xxxxxxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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