2021-05-05 17:17:44

by Sasha Levin

[permalink] [raw]
Subject: [PATCH AUTOSEL 5.4 41/46] qtnfmac: Fix possible buffer overflow in qtnf_event_handle_external_auth

From: Lee Gibson <[email protected]>

[ Upstream commit 130f634da1af649205f4a3dd86cbe5c126b57914 ]

Function qtnf_event_handle_external_auth calls memcpy without
checking the length.
A user could control that length and trigger a buffer overflow.
Fix by checking the length is within the maximum allowed size.

Signed-off-by: Lee Gibson <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
---
drivers/net/wireless/quantenna/qtnfmac/event.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/quantenna/qtnfmac/event.c b/drivers/net/wireless/quantenna/qtnfmac/event.c
index 7846383c8828..3f24dbdae8d0 100644
--- a/drivers/net/wireless/quantenna/qtnfmac/event.c
+++ b/drivers/net/wireless/quantenna/qtnfmac/event.c
@@ -599,8 +599,10 @@ qtnf_event_handle_external_auth(struct qtnf_vif *vif,
return 0;

if (ev->ssid_len) {
- memcpy(auth.ssid.ssid, ev->ssid, ev->ssid_len);
- auth.ssid.ssid_len = ev->ssid_len;
+ int len = clamp_val(ev->ssid_len, 0, IEEE80211_MAX_SSID_LEN);
+
+ memcpy(auth.ssid.ssid, ev->ssid, len);
+ auth.ssid.ssid_len = len;
}

auth.key_mgmt_suite = le32_to_cpu(ev->akm_suite);
--
2.30.2