[PATCH 4.4 36/76] uwb: hwa-rc: fix NULL-deref at probe

From: Greg Kroah-Hartman
Date: Tue Mar 28 2017 - 09:52:33 EST


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

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

From: Johan Hovold <johan@xxxxxxxxxx>

commit daf229b15907fbfdb6ee183aac8ca428cb57e361 upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer should a malicious device lack endpoints.

Note that the dereference happens in the start callback which is called
during probe.

Fixes: de520b8bd552 ("uwb: add HWA radio controller driver")
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@xxxxxxxxx>
Cc: David Vrabel <david.vrabel@xxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/uwb/hwa-rc.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/uwb/hwa-rc.c
+++ b/drivers/uwb/hwa-rc.c
@@ -825,6 +825,9 @@ static int hwarc_probe(struct usb_interf
struct hwarc *hwarc;
struct device *dev = &iface->dev;

+ if (iface->cur_altsetting->desc.bNumEndpoints < 1)
+ return -ENODEV;
+
result = -ENOMEM;
uwb_rc = uwb_rc_alloc();
if (uwb_rc == NULL) {