[PATCH 4.9 42/62] USB: serial: whiteheat: fix potential slab corruption

Greg Kroah-Hartman
2019-11-04T21:51:08Z

From: Johan Hovold <johan@kernel.org>

commit 1251dab9e0a2c4d0d2d48370ba5baa095a5e8774 upstream.

Fix a user-controlled slab buffer overflow due to a missing sanity check
on the bulk-out transfer buffer used for control requests.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191029102354.2733-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/serial/whiteheat.c | 4 ++++
1 file changed, 4 insertions(+)

--- a/drivers/usb/serial/whiteheat.c
+++ b/drivers/usb/serial/whiteheat.c
@@ -604,6 +604,10 @@ static int firm_send_command(struct usb_

command_port = port->serial->port[COMMAND_PORT];
command_info = usb_get_serial_port_data(command_port);
+
+ if (command_port->bulk_out_size < datasize + 1)
+ return -EIO;
+
mutex_lock(&command_info->mutex);
command_info->command_finished = false;