This is a note to let you know that I've just added the patch titled
nfc: fix refcount leak in llcp_sock_connect()
to the 5.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfc-fix-refcount-leak-in-llcp_sock_connect.patch
and it can be found in the queue-5.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 8a4cd82d62b5ec7e5482333a72b58a4eea4979f0 Mon Sep 17 00:00:00 2001
From: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
Date: Thu, 25 Mar 2021 11:51:11 +0800
Subject: nfc: fix refcount leak in llcp_sock_connect()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
From: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
commit 8a4cd82d62b5ec7e5482333a72b58a4eea4979f0 upstream.
nfc_llcp_local_get() is invoked in llcp_sock_connect(),
but nfc_llcp_local_put() is not invoked in subsequent failure branches.
As a result, refcount leakage occurs.
To fix it, add calling nfc_llcp_local_put().
fix CVE-2020-25671
Fixes: c7aa12252f51 ("NFC: Take a reference on the LLCP local pointer when creating a socket")
Reported-by: "kiyin(尹亮)" <kiyin@xxxxxxxxxxx>
Link: https://www.openwall.com/lists/oss-security/2020/11/01/1
Cc: <stable@xxxxxxxxxxxxxxx> #v3.6
Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/nfc/llcp_sock.c | 2 ++
1 file changed, 2 insertions(+)
--- a/net/nfc/llcp_sock.c
+++ b/net/nfc/llcp_sock.c
@@ -704,6 +704,7 @@ static int llcp_sock_connect(struct sock
llcp_sock->local = nfc_llcp_local_get(local);
llcp_sock->ssap = nfc_llcp_get_local_ssap(local);
if (llcp_sock->ssap == LLCP_SAP_MAX) {
+ nfc_llcp_local_put(llcp_sock->local);
ret = -ENOMEM;
goto put_dev;
}
@@ -748,6 +749,7 @@ sock_unlink:
sock_llcp_release:
nfc_llcp_put_ssap(local, llcp_sock->ssap);
+ nfc_llcp_local_put(llcp_sock->local);
put_dev:
nfc_put_device(dev);
Patches currently in stable-queue which might be from nixiaoming@xxxxxxxxxx are
queue-5.11/nfc-avoid-endless-loops-caused-by-repeated-llcp_sock_connect.patch
queue-5.11/nfc-fix-memory-leak-in-llcp_sock_connect.patch
queue-5.11/nfc-fix-refcount-leak-in-llcp_sock_bind.patch
queue-5.11/nfc-fix-refcount-leak-in-llcp_sock_connect.patch
