From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Jason Wang , "David S. Miller" Subject: [PATCH 4.4 21/31] vhost_net: validate sock before trying to put its fd Date: Fri, 20 Jul 2018 14:13:51 +0200 Message-Id: <20180720121340.919756011@linuxfoundation.org> In-Reply-To: <20180720121340.158484922@linuxfoundation.org> References: <20180720121340.158484922@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jason Wang [ Upstream commit b8f1f65882f07913157c44673af7ec0b308d03eb ] Sock will be NULL if we pass -1 to vhost_net_set_backend(), but when we meet errors during ubuf allocation, the code does not check for NULL before calling sockfd_put(), this will lead NULL dereferencing. Fixing by checking sock pointer before. Fixes: bab632d69ee4 ("vhost: vhost TX zero-copy support") Reported-by: Dan Carpenter Signed-off-by: Jason Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/vhost/net.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -955,7 +955,8 @@ err_used: if (ubufs) vhost_net_ubuf_put_wait_and_free(ubufs); err_ubufs: - sockfd_put(sock); + if (sock) + sockfd_put(sock); err_vq: mutex_unlock(&vq->mutex); err: