[PATCH 3.16 026/134] ath9k_htc: fix NULL-deref at probe

Ben Hutchings
2017-08-18T13:15:43Z

From: Johan Hovold <johan@kernel.org>

commit ebeb36670ecac36c179b5fb5d5c88ff03ba191ec upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory beyond the endpoint array should a
malicious device lack the expected endpoints.

Fixes: 36bcce430657 ("ath9k_htc: Handle storage devices")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/net/wireless/ath/ath9k/hif_usb.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/net/wireless/ath/ath9k/hif_usb.c
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.c
@@ -1145,6 +1145,9 @@ static int send_eject_command(struct usb
u8 bulk_out_ep;
int r;

+ if (iface_desc->desc.bNumEndpoints < 2)
+ return -ENODEV;
+
/* Find bulk out endpoint */
for (r = 1; r >= 0; r--) {
endpoint = &iface_desc->endpoint[r].desc;