From: Jared Suttles <jared.suttles@motorola.com>
Date: Thu, 30 Jul 2009 21:13:27 +0000 (-0500)
Subject: drivers: usb: gadget: handle NULL descriptors in composite config_buf
X-Git-Tag: firefly_0821_release~9833^2~5^2~289
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=9fd9743c8866f2d4145654b302a6e59b71dc5203;p=firefly-linux-kernel-4.4.55.git

drivers: usb: gadget: handle NULL descriptors in composite config_buf

This fixes a problem in enumeration after a gadget function is removed.

Submitted on behalf of RaviKumar Vembu <ravi.v@motorola.com>

Signed-off-by: Jared Suttles <jared.suttles@motorola.com>
Signed-off-by: Mike Lockwood <lockwood@android.com>
---

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 1160c55de7f2..65012ff1c2ed 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -236,6 +236,7 @@ static int config_buf(struct usb_configuration *config,
 	int				len = USB_BUFSIZ - USB_DT_CONFIG_SIZE;
 	struct usb_function		*f;
 	int				status;
+	int				interfaceCount = 0;
 
 	/* write the config descriptor */
 	c = buf;
@@ -266,8 +267,16 @@ static int config_buf(struct usb_configuration *config,
 			descriptors = f->hs_descriptors;
 		else
 			descriptors = f->descriptors;
-		if (!descriptors)
+		if (!descriptors || descriptors[0] == NULL) {
+			for (; f != config->interface[interfaceCount];) {
+				interfaceCount++;
+				c->bNumInterfaces--;
+			}
 			continue;
+		}
+		for (; f != config->interface[interfaceCount];)
+			interfaceCount++;
+
 		status = usb_descriptor_fillbuf(next, len,
 			(const struct usb_descriptor_header **) descriptors);
 		if (status < 0)