From: Alan Stern <stern@rowland.harvard.edu>
Date: Tue, 20 Apr 2010 14:40:59 +0000 (-0400)
Subject: USB: don't choose configs with no interfaces
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=62f9cfa3ece58268b3e92ca59c23b175f86205aa;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

USB: don't choose configs with no interfaces

This patch (as1372) fixes a bug in the routine that chooses the
default configuration to install when a new USB device is detected.
The algorithm is supposed to look for a config whose first interface
is for a non-vendor-specific class.  But the way it's currently
written, it will also accept a config with no interfaces at all, which
is not very useful.  (Believe it or not, such things do exist.)

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Andrew Victor <avictor.za@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c
index bdf87a8414a1..2c95153c0f24 100644
--- a/drivers/usb/core/generic.c
+++ b/drivers/usb/core/generic.c
@@ -120,7 +120,7 @@ int usb_choose_configuration(struct usb_device *udev)
 		 * than a vendor-specific driver. */
 		else if (udev->descriptor.bDeviceClass !=
 						USB_CLASS_VENDOR_SPEC &&
-				(!desc || desc->bInterfaceClass !=
+				(desc && desc->bInterfaceClass !=
 						USB_CLASS_VENDOR_SPEC)) {
 			best = c;
 			break;