Path: csiph.com!1.us.feeder.erje.net!2.eu.feeder.erje.net!feeder.erje.net!1.eu.feeder.erje.net!weretis.net!feeder4.news.weretis.net!news.unit0.net!news.panservice.it!bofh.it!news.nic.it!robomod From: Greg Kroah-Hartman Newsgroups: linux.kernel Subject: [PATCH 4.4 28/35] USB: serial: io_ti: fix information leak in completion handler Date: Thu, 16 Mar 2017 16:10:02 +0100 Message-ID: References: X-Original-To: linux-kernel@vger.kernel.org X-Mailer: git-send-email 2.12.0 User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 34 Organization: linux.* mail to news gateway X-Original-Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold X-Original-Date: Thu, 16 Mar 2017 23:29:47 +0900 X-Original-Message-ID: <20170316142908.625141396@linuxfoundation.org> X-Original-References: <20170316142906.685052998@linuxfoundation.org> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1602459 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 654b404f2a222f918af9b0cd18ad469d0c941a8e upstream. Add missing sanity check to the bulk-in completion handler to avoid an integer underflow that can be triggered by a malicious device. This avoids leaking 128 kB of memory content from after the URB transfer buffer to user space. Fixes: 8c209e6782ca ("USB: make actual_length in struct urb field u32") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/io_ti.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/serial/io_ti.c +++ b/drivers/usb/serial/io_ti.c @@ -1761,7 +1761,7 @@ static void edge_bulk_in_callback(struct port_number = edge_port->port->port_number; - if (edge_port->lsr_event) { + if (urb->actual_length > 0 && edge_port->lsr_event) { edge_port->lsr_event = 0; dev_dbg(dev, "%s ===== Port %u LSR Status = %02x, Data = %02x ======\n", __func__, port_number, edge_port->lsr_mask, *data);