From: Colin Ian King <colin.king@canonical.com>
Date: Tue, 14 Nov 2017 16:18:28 +0000 (+0000)
Subject: usb: gadget: don't dereference g until after it has been null checked
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=0479bc01767ff58170a2f1ae27e6b98f9dfa01b9;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

usb: gadget: don't dereference g until after it has been null checked


[ Upstream commit b2fc059fa549fe6881d4c1f8d698b0f50bcd16ec ]

Avoid dereferencing pointer g until after g has been sanity null checked;
move the assignment of cdev much later when it is required into a more
local scope.

Detected by CoverityScan, CID#1222135 ("Dereference before null check")

Fixes: b785ea7ce662 ("usb: gadget: composite: fix ep->maxburst initialization")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 5d061b3d8224..ed9346f0b000 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -150,7 +150,6 @@ int config_ep_by_speed(struct usb_gadget *g,
 			struct usb_function *f,
 			struct usb_ep *_ep)
 {
-	struct usb_composite_dev	*cdev = get_gadget_data(g);
 	struct usb_endpoint_descriptor *chosen_desc = NULL;
 	struct usb_descriptor_header **speed_desc = NULL;
 
@@ -229,8 +228,12 @@ ep_found:
 			_ep->maxburst = comp_desc->bMaxBurst + 1;
 			break;
 		default:
-			if (comp_desc->bMaxBurst != 0)
+			if (comp_desc->bMaxBurst != 0) {
+				struct usb_composite_dev *cdev;
+
+				cdev = get_gadget_data(g);
 				ERROR(cdev, "ep0 bMaxBurst must be 0\n");
+			}
 			_ep->maxburst = 1;
 			break;
 		}