patch "usb: musb: gadget: misplaced out of bounds check" added to usb-testing

patch "usb: musb: gadget: misplaced out of bounds check" added to usb-testing

[gregkh]

This is a note to let you know that I've just added the patch titled

    usb: musb: gadget: misplaced out of bounds check

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-testing branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will be merged to the usb-next branch sometime soon,
after it passes testing, and the merge window is open.

If you have any questions about this process, please let me know.


>From af6f8529098aeb0e56a68671b450cf74e7a64fcd Mon Sep 17 00:00:00 2001
From: Heinrich Schuchardt <xypron.glpk@gmx.de>
Date: Thu, 29 Mar 2018 10:48:28 -0500
Subject: usb: musb: gadget: misplaced out of bounds check

musb->endpoints[] has array size MUSB_C_NUM_EPS.
We must check array bounds before accessing the array and not afterwards.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Bin Liu <b-liu@ti.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/musb/musb_gadget_ep0.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/musb/musb_gadget_ep0.c b/drivers/usb/musb/musb_gadget_ep0.c
index 18da4873e52e..91a5027b5c1f 100644
--- a/drivers/usb/musb/musb_gadget_ep0.c
+++ b/drivers/usb/musb/musb_gadget_ep0.c
@@ -89,15 +89,19 @@ static int service_tx_status_request(
 		}
 
 		is_in = epnum & USB_DIR_IN;
-		if (is_in) {
-			epnum &= 0x0f;
+		epnum &= 0x0f;
+		if (epnum >= MUSB_C_NUM_EPS) {
+			handled = -EINVAL;
+			break;
+		}
+
+		if (is_in)
 			ep = &musb->endpoints[epnum].ep_in;
-		} else {
+		else
 			ep = &musb->endpoints[epnum].ep_out;
-		}
 		regs = musb->endpoints[epnum].regs;
 
-		if (epnum >= MUSB_C_NUM_EPS || !ep->desc) {
+		if (!ep->desc) {
 			handled = -EINVAL;
 			break;
 		}
-- 
2.16.3