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Message-ID: <tencent_5153B668C0283CAA15AA518325346E026A09@qq.com>
From:   Zhang Shurong <zhang_shurong@foxmail.com>
To:     gregkh@linuxfoundation.org
Cc:     error27@gmail.com, xu.panda@zte.com.cn,
        linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org,
        Zhang Shurong <zhang_shurong@foxmail.com>
Subject: [PATCH] staging: ks7010: potential buffer overflow in ks_wlan_set_encode_ext()
Date:   Sun,  9 Jul 2023 13:50:07 +0800
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The "exc->key_len" is a u16 that comes from the user.  If it's over
IW_ENCODING_TOKEN_MAX (64) that could lead to memory corruption.

Fixes: b121d84882b9 ("staging: ks7010: simplify calls to memcpy()")

Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
---
 drivers/staging/ks7010/ks_wlan_net.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/ks7010/ks_wlan_net.c b/drivers/staging/ks7010/ks_wlan_net.c
index e03c87f0bfe7..0fb97a79ad0b 100644
--- a/drivers/staging/ks7010/ks_wlan_net.c
+++ b/drivers/staging/ks7010/ks_wlan_net.c
@@ -1583,8 +1583,10 @@ static int ks_wlan_set_encode_ext(struct net_device *dev,
 			commit |= SME_WEP_FLAG;
 		}
 		if (enc->key_len) {
-			memcpy(&key->key_val[0], &enc->key[0], enc->key_len);
-			key->key_len = enc->key_len;
+			int key_len = clamp_val(enc->key_len, 0, IW_ENCODING_TOKEN_MAX);
+
+			memcpy(&key->key_val[0], &enc->key[0], key_len);
+			key->key_len = key_len;
 			commit |= (SME_WEP_VAL1 << index);
 		}
 		break;
-- 
2.30.2