From: Zhang Shurong <zhang_shurong@foxmail.com>
Date: Sun, 9 Jul 2023 05:50:07 +0000 (+0800)
Subject: staging: ks7010: potential buffer overflow in ks_wlan_set_encode_ext()
X-Git-Tag: v4.14.322~36
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9496fb96ddeb740dc6b966f4a7d8dfb8b93921c6;p=thirdparty%2Fkernel%2Fstable.git

staging: ks7010: potential buffer overflow in ks_wlan_set_encode_ext()

commit 5f1c7031e044cb2fba82836d55cc235e2ad619dc upstream.

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()")
Cc: stable <stable@kernel.org>
Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/tencent_5153B668C0283CAA15AA518325346E026A09@qq.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/staging/ks7010/ks_wlan_net.c b/drivers/staging/ks7010/ks_wlan_net.c
index 9b71dc64f9b43..c5c37d4e0c6f5 100644
--- a/drivers/staging/ks7010/ks_wlan_net.c
+++ b/drivers/staging/ks7010/ks_wlan_net.c
@@ -1787,8 +1787,10 @@ 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;