From: Bin Liu <b-liu@ti.com>
Date: Mon, 30 Apr 2018 16:20:53 +0000 (-0500)
Subject: usb: musb: host: fix potential NULL pointer dereference
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=303e99bde8dcb6beaa6be738e025f9f9dd2703f1;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

usb: musb: host: fix potential NULL pointer dereference

commit 2b63f1329df2cd814c1f8353fae4853ace6521d1 upstream.

musb_start_urb() doesn't check the pass-in parameter if it is NULL.  But
in musb_bulk_nak_timeout() the parameter passed to musb_start_urb() is
returned from first_qh(), which could be NULL.

So wrap the musb_start_urb() call here with a if condition check to
avoid the potential NULL pointer dereference.

Fixes: f283862f3b5c ("usb: musb: NAK timeout scheme on bulk TX endpoint")
Cc: stable@vger.kernel.org # v3.7+
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index b5cc08d8aa22..5a6dca01a1d0 100644
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -1023,7 +1023,9 @@ static void musb_bulk_nak_timeout(struct musb *musb, struct musb_hw_ep *ep,
 			/* set tx_reinit and schedule the next qh */
 			ep->tx_reinit = 1;
 		}
-		musb_start_urb(musb, is_in, next_qh);
+
+		if (next_qh)
+			musb_start_urb(musb, is_in, next_qh);
 	}
 }