linux-kernel - [PATCH 5.4 08/19] qrtr: orphan socket in qrtr

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 30 Jul 2020 10:04:10 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        Eric Dumazet <eric.dumazet@...il.com>,
        Cong Wang <xiyou.wangcong@...il.com>,
        Eric Dumazet <edumazet@...gle.com>,
        "David S. Miller" <davem@...emloft.net>,
        syzbot+6720d64f31c081c2f708@...kaller.appspotmail.com
Subject: [PATCH 5.4 08/19] qrtr: orphan socket in qrtr_release()

From: Cong Wang <xiyou.wangcong@...il.com>

[ Upstream commit af9f691f0f5bdd1ade65a7b84927639882d7c3e5 ]

We have to detach sock from socket in qrtr_release(),
otherwise skb->sk may still reference to this socket
when the skb is released in tun->queue, particularly
sk->sk_wq still points to &sock->wq, which leads to
a UAF.

Reported-and-tested-by: syzbot+6720d64f31c081c2f708@...kaller.appspotmail.com
Fixes: 28fb4e59a47d ("net: qrtr: Expose tunneling endpoint to user space")
Cc: Bjorn Andersson <bjorn.andersson@...aro.org>
Cc: Eric Dumazet <eric.dumazet@...il.com>
Signed-off-by: Cong Wang <xiyou.wangcong@...il.com>
Reviewed-by: Eric Dumazet <edumazet@...gle.com>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 net/qrtr/qrtr.c |    1 +
 1 file changed, 1 insertion(+)

--- a/net/qrtr/qrtr.c
+++ b/net/qrtr/qrtr.c
@@ -1004,6 +1004,7 @@ static int qrtr_release(struct socket *s
 		sk->sk_state_change(sk);
 
 	sock_set_flag(sk, SOCK_DEAD);
+	sock_orphan(sk);
 	sock->sk = NULL;
 
 	if (!sock_flag(sk, SOCK_ZAPPED))