From: Xiaoming Ni <nixiaoming@huawei.com>
Date: Thu, 25 Mar 2021 03:51:12 +0000 (+0800)
Subject: nfc: fix memory leak in llcp_sock_connect()
X-Git-Tag: v4.4.267~34
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7ed6c0c7db2099792768150c070efca71e85bdf3;p=thirdparty%2Fkernel%2Fstable.git

nfc: fix memory leak in llcp_sock_connect()

commit 7574fcdbdcb335763b6b322f6928dc0fd5730451 upstream.

In llcp_sock_connect(), use kmemdup to allocate memory for
 "llcp_sock->service_name". The memory is not released in the sock_unlink
label of the subsequent failure branch.
As a result, memory leakage occurs.

fix CVE-2020-25672

Fixes: d646960f7986 ("NFC: Initial LLCP support")
Reported-by: "kiyin(尹亮)" <kiyin@tencent.com>
Link: https://www.openwall.com/lists/oss-security/2020/11/01/1
Cc: <stable@vger.kernel.org> #v3.3
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c
index 79ca5e60dc94e..7632593975449 100644
--- a/net/nfc/llcp_sock.c
+++ b/net/nfc/llcp_sock.c
@@ -751,6 +751,8 @@ sock_unlink:
 	nfc_llcp_local_put(llcp_sock->local);
 
 	nfc_llcp_sock_unlink(&local->connecting_sockets, sk);
+	kfree(llcp_sock->service_name);
+	llcp_sock->service_name = NULL;
 
 put_dev:
 	nfc_put_device(dev);