[PATCH AUTOSEL 4.19 004/158] ath6kl: add some bounds checking

From: Sasha Levin
Date: Mon Jul 15 2019 - 09:39:39 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit 5d6751eaff672ea77642e74e92e6c0ac7f9709ab ]

The "ev->traffic_class" and "reply->ac" variables come from the network
and they're used as an offset into the wmi->stream_exist_for_ac[] array.
Those variables are u8 so they can be 0-255 but the stream_exist_for_ac[]
array only has WMM_NUM_AC (4) elements. We need to add a couple bounds
checks to prevent array overflows.

I also modified one existing check from "if (traffic_class > 3) {" to
"if (traffic_class >= WMM_NUM_AC) {" just to make them all consistent.

Fixes: bdcd81707973 (" Add ath6kl cleaned up driver")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/wireless/ath/ath6kl/wmi.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath6kl/wmi.c b/drivers/net/wireless/ath/ath6kl/wmi.c
index 777acc564ac9..bc7916f2add0 100644
--- a/drivers/net/wireless/ath/ath6kl/wmi.c
+++ b/drivers/net/wireless/ath/ath6kl/wmi.c
@@ -1178,6 +1178,10 @@ static int ath6kl_wmi_pstream_timeout_event_rx(struct wmi *wmi, u8 *datap,
return -EINVAL;

ev = (struct wmi_pstream_timeout_event *) datap;
+ if (ev->traffic_class >= WMM_NUM_AC) {
+ ath6kl_err("invalid traffic class: %d\n", ev->traffic_class);
+ return -EINVAL;
+ }

/*
* When the pstream (fat pipe == AC) timesout, it means there were
@@ -1519,6 +1523,10 @@ static int ath6kl_wmi_cac_event_rx(struct wmi *wmi, u8 *datap, int len,
return -EINVAL;

reply = (struct wmi_cac_event *) datap;
+ if (reply->ac >= WMM_NUM_AC) {
+ ath6kl_err("invalid AC: %d\n", reply->ac);
+ return -EINVAL;
+ }

if ((reply->cac_indication == CAC_INDICATION_ADMISSION_RESP) &&
(reply->status_code != IEEE80211_TSPEC_STATUS_ADMISS_ACCEPTED)) {
@@ -2635,7 +2643,7 @@ int ath6kl_wmi_delete_pstream_cmd(struct wmi *wmi, u8 if_idx, u8 traffic_class,
u16 active_tsids = 0;
int ret;

- if (traffic_class > 3) {
+ if (traffic_class >= WMM_NUM_AC) {
ath6kl_err("invalid traffic class: %d\n", traffic_class);
return -EINVAL;
}
--
2.20.1