Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Xiumei Mu <xmu@redhat.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Stefano Garzarella <sgarzare@redhat.com>,
        Jorgen Hansen <jhansen@vmware.com>,
        "David S. Miller" <davem@davemloft.net>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.4 02/20] vsock: cope with memory allocation failure at socket creation time
Date:   Thu, 21 Feb 2019 15:35:32 +0100
Message-Id: <20190221141946.847448508@linuxfoundation.org>
In-Reply-To: <20190221141946.772985220@linuxfoundation.org>
References: <20190221141946.772985220@linuxfoundation.org>
User-Agent: quilt/0.65
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit 225d9464268599a5b4d094d02ec17808e44c7553 ]

In the unlikely event that the kmalloc call in vmci_transport_socket_init()
fails, we end-up calling vmci_transport_destruct() with a NULL vmci_trans()
and oopsing.

This change addresses the above explicitly checking for zero vmci_trans()
at destruction time.

Reported-by: Xiumei Mu <xmu@redhat.com>
Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/vmw_vsock/vmci_transport.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c
index d24773552b641..217810674c358 100644
--- a/net/vmw_vsock/vmci_transport.c
+++ b/net/vmw_vsock/vmci_transport.c
@@ -1656,6 +1656,10 @@ static void vmci_transport_cleanup(struct work_struct *work)
 
 static void vmci_transport_destruct(struct vsock_sock *vsk)
 {
+	/* transport can be NULL if we hit a failure at init() time */
+	if (!vmci_trans(vsk))
+		return;
+
 	/* Ensure that the detach callback doesn't use the sk/vsk
 	 * we are about to destruct.
 	 */
-- 
2.19.1