[PATCH 2.6.32 03/55] USB: visor: fix null-deref at probe

From: Willy Tarreau
Date: Fri Mar 04 2016 - 11:17:00 EST


2.6.32-longterm review patch. If anyone has any objections, please let me know.

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

From: Johan Hovold <johan@xxxxxxxxxx>

commit cac9b50b0d75a1d50d6c056ff65c005f3224c8e0 upstream.

Fix null-pointer dereference at probe should a (malicious) Treo device
lack the expected endpoints.

Specifically, the Treo port-setup hack was dereferencing the bulk-in and
interrupt-in urbs without first making sure they had been allocated by
core.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
drivers/usb/serial/visor.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index e9229c5..741d834 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -878,6 +878,11 @@ static int treo_attach(struct usb_serial *serial)

dbg("%s", __func__);

+ if (serial->num_bulk_in < 2 || serial->num_interrupt_in < 2) {
+ dev_err(&serial->interface->dev, "missing endpoints\n");
+ return -ENODEV;
+ }
+
/*
* It appears that Treos and Kyoceras want to use the
* 1st bulk in endpoint to communicate with the 2nd bulk out endpoint,
--
1.7.12.2.21.g234cd45.dirty