From: Kuen-Han Tsai <khtsai@google.com>
Date: Mon, 20 Oct 2025 16:20:32 +0000 (-0400)
Subject: usb: gadget: Introduce free_usb_request helper
X-Git-Tag: v5.15.196~5
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d44e82f46cd0e348837c31e629bf45d0dcabbe3b;p=thirdparty%2Fkernel%2Fstable.git

usb: gadget: Introduce free_usb_request helper

[ Upstream commit 201c53c687f2b55a7cc6d9f4000af4797860174b ]

Introduce the free_usb_request() function that frees both the request's
buffer and the request itself.

This function serves as the cleanup callback for DEFINE_FREE() to enable
automatic, scope-based cleanup for usb_request pointers.

Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
Link: https://lore.kernel.org/r/20250916-ready-v1-2-4997bf277548@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250916-ready-v1-2-4997bf277548@google.com
Stable-dep-of: 75a5b8d4ddd4 ("usb: gadget: f_ncm: Refactor bind path to use __free()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 35dc1009a703..78f78dfbf92a 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -17,6 +17,7 @@
 #ifndef __LINUX_USB_GADGET_H
 #define __LINUX_USB_GADGET_H
 
+#include <linux/cleanup.h>
 #include <linux/device.h>
 #include <linux/errno.h>
 #include <linux/init.h>
@@ -292,6 +293,28 @@ static inline void usb_ep_fifo_flush(struct usb_ep *ep)
 
 /*-------------------------------------------------------------------------*/
 
+/**
+ * free_usb_request - frees a usb_request object and its buffer
+ * @req: the request being freed
+ *
+ * This helper function frees both the request's buffer and the request object
+ * itself by calling usb_ep_free_request(). Its signature is designed to be used
+ * with DEFINE_FREE() to enable automatic, scope-based cleanup for usb_request
+ * pointers.
+ */
+static inline void free_usb_request(struct usb_request *req)
+{
+	if (!req)
+		return;
+
+	kfree(req->buf);
+	usb_ep_free_request(req->ep, req);
+}
+
+DEFINE_FREE(free_usb_request, struct usb_request *, free_usb_request(_T))
+
+/*-------------------------------------------------------------------------*/
+
 struct usb_dcd_config_params {
 	__u8  bU1devExitLat;	/* U1 Device exit Latency */
 #define USB_DEFAULT_U1_DEV_EXIT_LAT	0x01	/* Less then 1 microsec */