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* FAILED: patch "[PATCH] usb: gadget: f_ncm: Refactor bind path to use __free()" failed to apply to 5.15-stable tree
@ 2025-10-16  9:18 gregkh
  2025-10-20 16:20 ` [PATCH 5.15.y 1/3] usb: gadget: Store endpoint pointer in usb_request Sasha Levin
  0 siblings, 1 reply; 5+ messages in thread
From: gregkh @ 2025-10-16  9:18 UTC (permalink / raw)
  To: khtsai, gregkh; +Cc: stable


The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 75a5b8d4ddd4eb6b16cb0b475d14ff4ae64295ef
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025101658-ajar-suggest-f20a@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 75a5b8d4ddd4eb6b16cb0b475d14ff4ae64295ef Mon Sep 17 00:00:00 2001
From: Kuen-Han Tsai <khtsai@google.com>
Date: Tue, 16 Sep 2025 16:21:34 +0800
Subject: [PATCH] usb: gadget: f_ncm: Refactor bind path to use __free()

After an bind/unbind cycle, the ncm->notify_req is left stale. If a
subsequent bind fails, the unified error label attempts to free this
stale request, leading to a NULL pointer dereference when accessing
ep->ops->free_request.

Refactor the error handling in the bind path to use the __free()
automatic cleanup mechanism.

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
Call trace:
 usb_ep_free_request+0x2c/0xec
 ncm_bind+0x39c/0x3dc
 usb_add_function+0xcc/0x1f0
 configfs_composite_bind+0x468/0x588
 gadget_bind_driver+0x104/0x270
 really_probe+0x190/0x374
 __driver_probe_device+0xa0/0x12c
 driver_probe_device+0x3c/0x218
 __device_attach_driver+0x14c/0x188
 bus_for_each_drv+0x10c/0x168
 __device_attach+0xfc/0x198
 device_initial_probe+0x14/0x24
 bus_probe_device+0x94/0x11c
 device_add+0x268/0x48c
 usb_add_gadget+0x198/0x28c
 dwc3_gadget_init+0x700/0x858
 __dwc3_set_mode+0x3cc/0x664
 process_scheduled_works+0x1d8/0x488
 worker_thread+0x244/0x334
 kthread+0x114/0x1bc
 ret_from_fork+0x10/0x20

Fixes: 9f6ce4240a2b ("usb: gadget: f_ncm.c added")
Cc: stable@kernel.org
Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
Link: https://lore.kernel.org/r/20250916-ready-v1-3-4997bf277548@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250916-ready-v1-3-4997bf277548@google.com

diff --git a/drivers/usb/gadget/function/f_ncm.c b/drivers/usb/gadget/function/f_ncm.c
index 58b0dd575af3..0148d60926dc 100644
--- a/drivers/usb/gadget/function/f_ncm.c
+++ b/drivers/usb/gadget/function/f_ncm.c
@@ -11,6 +11,7 @@
  * Copyright (C) 2008 Nokia Corporation
  */
 
+#include <linux/cleanup.h>
 #include <linux/kernel.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
@@ -20,6 +21,7 @@
 #include <linux/string_choices.h>
 
 #include <linux/usb/cdc.h>
+#include <linux/usb/gadget.h>
 
 #include "u_ether.h"
 #include "u_ether_configfs.h"
@@ -1436,18 +1438,18 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	struct usb_ep		*ep;
 	struct f_ncm_opts	*ncm_opts;
 
+	struct usb_os_desc_table	*os_desc_table __free(kfree) = NULL;
+	struct usb_request		*request __free(free_usb_request) = NULL;
+
 	if (!can_support_ecm(cdev->gadget))
 		return -EINVAL;
 
 	ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
 
 	if (cdev->use_os_string) {
-		f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
-					   GFP_KERNEL);
-		if (!f->os_desc_table)
+		os_desc_table = kzalloc(sizeof(*os_desc_table), GFP_KERNEL);
+		if (!os_desc_table)
 			return -ENOMEM;
-		f->os_desc_n = 1;
-		f->os_desc_table[0].os_desc = &ncm_opts->ncm_os_desc;
 	}
 
 	mutex_lock(&ncm_opts->lock);
@@ -1459,16 +1461,15 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	mutex_unlock(&ncm_opts->lock);
 
 	if (status)
-		goto fail;
+		return status;
 
 	ncm_opts->bound = true;
 
 	us = usb_gstrings_attach(cdev, ncm_strings,
 				 ARRAY_SIZE(ncm_string_defs));
-	if (IS_ERR(us)) {
-		status = PTR_ERR(us);
-		goto fail;
-	}
+	if (IS_ERR(us))
+		return PTR_ERR(us);
+
 	ncm_control_intf.iInterface = us[STRING_CTRL_IDX].id;
 	ncm_data_nop_intf.iInterface = us[STRING_DATA_IDX].id;
 	ncm_data_intf.iInterface = us[STRING_DATA_IDX].id;
@@ -1478,20 +1479,16 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	/* allocate instance-specific interface IDs */
 	status = usb_interface_id(c, f);
 	if (status < 0)
-		goto fail;
+		return status;
 	ncm->ctrl_id = status;
 	ncm_iad_desc.bFirstInterface = status;
 
 	ncm_control_intf.bInterfaceNumber = status;
 	ncm_union_desc.bMasterInterface0 = status;
 
-	if (cdev->use_os_string)
-		f->os_desc_table[0].if_id =
-			ncm_iad_desc.bFirstInterface;
-
 	status = usb_interface_id(c, f);
 	if (status < 0)
-		goto fail;
+		return status;
 	ncm->data_id = status;
 
 	ncm_data_nop_intf.bInterfaceNumber = status;
@@ -1500,35 +1497,31 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 
 	ecm_desc.wMaxSegmentSize = cpu_to_le16(ncm_opts->max_segment_size);
 
-	status = -ENODEV;
-
 	/* allocate instance-specific endpoints */
 	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_in_desc);
 	if (!ep)
-		goto fail;
+		return -ENODEV;
 	ncm->port.in_ep = ep;
 
 	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_out_desc);
 	if (!ep)
-		goto fail;
+		return -ENODEV;
 	ncm->port.out_ep = ep;
 
 	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_notify_desc);
 	if (!ep)
-		goto fail;
+		return -ENODEV;
 	ncm->notify = ep;
 
-	status = -ENOMEM;
-
 	/* allocate notification request and buffer */
-	ncm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
-	if (!ncm->notify_req)
-		goto fail;
-	ncm->notify_req->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
-	if (!ncm->notify_req->buf)
-		goto fail;
-	ncm->notify_req->context = ncm;
-	ncm->notify_req->complete = ncm_notify_complete;
+	request = usb_ep_alloc_request(ep, GFP_KERNEL);
+	if (!request)
+		return -ENOMEM;
+	request->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
+	if (!request->buf)
+		return -ENOMEM;
+	request->context = ncm;
+	request->complete = ncm_notify_complete;
 
 	/*
 	 * support all relevant hardware speeds... we expect that when
@@ -1548,7 +1541,7 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
 			ncm_ss_function, ncm_ss_function);
 	if (status)
-		goto fail;
+		return status;
 
 	/*
 	 * NOTE:  all that is done without knowing or caring about
@@ -1561,23 +1554,18 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 
 	hrtimer_setup(&ncm->task_timer, ncm_tx_timeout, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
 
+	if (cdev->use_os_string) {
+		os_desc_table[0].os_desc = &ncm_opts->ncm_os_desc;
+		os_desc_table[0].if_id = ncm_iad_desc.bFirstInterface;
+		f->os_desc_table = no_free_ptr(os_desc_table);
+		f->os_desc_n = 1;
+	}
+	ncm->notify_req = no_free_ptr(request);
+
 	DBG(cdev, "CDC Network: IN/%s OUT/%s NOTIFY/%s\n",
 			ncm->port.in_ep->name, ncm->port.out_ep->name,
 			ncm->notify->name);
 	return 0;
-
-fail:
-	kfree(f->os_desc_table);
-	f->os_desc_n = 0;
-
-	if (ncm->notify_req) {
-		kfree(ncm->notify_req->buf);
-		usb_ep_free_request(ncm->notify, ncm->notify_req);
-	}
-
-	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
-
-	return status;
 }
 
 static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 5.15.y 1/3] usb: gadget: Store endpoint pointer in usb_request
  2025-10-16  9:19 FAILED: patch "[PATCH] usb: gadget: f_acm: Refactor bind path to use __free()" failed to apply to 5.15-stable tree gregkh
@ 2025-10-20 16:19 ` Sasha Levin
  0 siblings, 0 replies; 5+ messages in thread
From: Sasha Levin @ 2025-10-20 16:19 UTC (permalink / raw)
  To: stable; +Cc: Kuen-Han Tsai, Greg Kroah-Hartman, Sasha Levin

From: Kuen-Han Tsai <khtsai@google.com>

[ Upstream commit bfb1d99d969fe3b892db30848aeebfa19d21f57f ]

Gadget function drivers often have goto-based error handling in their
bind paths, which can be bug-prone. Refactoring these paths to use
__free() scope-based cleanup is desirable, but currently blocked.

The blocker is that usb_ep_free_request(ep, req) requires two
parameters, while the __free() mechanism can only pass a pointer to the
request itself.

Store an endpoint pointer in the struct usb_request. The pointer is
populated centrally in usb_ep_alloc_request() on every successful
allocation, making the request object self-contained.

Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
Link: https://lore.kernel.org/r/20250916-ready-v1-1-4997bf277548@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250916-ready-v1-1-4997bf277548@google.com
Stable-dep-of: 47b2116e54b4 ("usb: gadget: f_acm: Refactor bind path to use __free()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/gadget/udc/core.c | 3 +++
 include/linux/usb/gadget.h    | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index d865c4677ad7c..b59b6900e7051 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -177,6 +177,9 @@ struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
 
 	req = ep->ops->alloc_request(ep, gfp_flags);
 
+	if (req)
+		req->ep = ep;
+
 	trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM);
 
 	return req;
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index e4feeaa8bab30..35dc1009a703f 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -33,6 +33,7 @@ struct usb_ep;
 
 /**
  * struct usb_request - describes one i/o request
+ * @ep: The associated endpoint set by usb_ep_alloc_request().
  * @buf: Buffer used for data.  Always provide this; some controllers
  *	only use PIO, or don't use DMA for some endpoints.
  * @dma: DMA address corresponding to 'buf'.  If you don't set this
@@ -98,6 +99,7 @@ struct usb_ep;
  */
 
 struct usb_request {
+	struct usb_ep		*ep;
 	void			*buf;
 	unsigned		length;
 	dma_addr_t		dma;
-- 
2.51.0


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 5.15.y 1/3] usb: gadget: Store endpoint pointer in usb_request
  2025-10-16  9:18 FAILED: patch "[PATCH] usb: gadget: f_ncm: Refactor bind path to use __free()" failed to apply to 5.15-stable tree gregkh
@ 2025-10-20 16:20 ` Sasha Levin
  2025-10-20 16:20   ` [PATCH 5.15.y 2/3] usb: gadget: Introduce free_usb_request helper Sasha Levin
  2025-10-20 16:20   ` [PATCH 5.15.y 3/3] usb: gadget: f_ncm: Refactor bind path to use __free() Sasha Levin
  0 siblings, 2 replies; 5+ messages in thread
From: Sasha Levin @ 2025-10-20 16:20 UTC (permalink / raw)
  To: stable; +Cc: Kuen-Han Tsai, Greg Kroah-Hartman, Sasha Levin

From: Kuen-Han Tsai <khtsai@google.com>

[ Upstream commit bfb1d99d969fe3b892db30848aeebfa19d21f57f ]

Gadget function drivers often have goto-based error handling in their
bind paths, which can be bug-prone. Refactoring these paths to use
__free() scope-based cleanup is desirable, but currently blocked.

The blocker is that usb_ep_free_request(ep, req) requires two
parameters, while the __free() mechanism can only pass a pointer to the
request itself.

Store an endpoint pointer in the struct usb_request. The pointer is
populated centrally in usb_ep_alloc_request() on every successful
allocation, making the request object self-contained.

Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
Link: https://lore.kernel.org/r/20250916-ready-v1-1-4997bf277548@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250916-ready-v1-1-4997bf277548@google.com
Stable-dep-of: 75a5b8d4ddd4 ("usb: gadget: f_ncm: Refactor bind path to use __free()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/gadget/udc/core.c | 3 +++
 include/linux/usb/gadget.h    | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index d865c4677ad7c..b59b6900e7051 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -177,6 +177,9 @@ struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
 
 	req = ep->ops->alloc_request(ep, gfp_flags);
 
+	if (req)
+		req->ep = ep;
+
 	trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM);
 
 	return req;
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index e4feeaa8bab30..35dc1009a703f 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -33,6 +33,7 @@ struct usb_ep;
 
 /**
  * struct usb_request - describes one i/o request
+ * @ep: The associated endpoint set by usb_ep_alloc_request().
  * @buf: Buffer used for data.  Always provide this; some controllers
  *	only use PIO, or don't use DMA for some endpoints.
  * @dma: DMA address corresponding to 'buf'.  If you don't set this
@@ -98,6 +99,7 @@ struct usb_ep;
  */
 
 struct usb_request {
+	struct usb_ep		*ep;
 	void			*buf;
 	unsigned		length;
 	dma_addr_t		dma;
-- 
2.51.0


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 5.15.y 2/3] usb: gadget: Introduce free_usb_request helper
  2025-10-20 16:20 ` [PATCH 5.15.y 1/3] usb: gadget: Store endpoint pointer in usb_request Sasha Levin
@ 2025-10-20 16:20   ` Sasha Levin
  2025-10-20 16:20   ` [PATCH 5.15.y 3/3] usb: gadget: f_ncm: Refactor bind path to use __free() Sasha Levin
  1 sibling, 0 replies; 5+ messages in thread
From: Sasha Levin @ 2025-10-20 16:20 UTC (permalink / raw)
  To: stable; +Cc: Kuen-Han Tsai, Greg Kroah-Hartman, Sasha Levin

From: Kuen-Han Tsai <khtsai@google.com>

[ 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>
---
 include/linux/usb/gadget.h | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 35dc1009a703f..78f78dfbf92a9 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 */
-- 
2.51.0


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 5.15.y 3/3] usb: gadget: f_ncm: Refactor bind path to use __free()
  2025-10-20 16:20 ` [PATCH 5.15.y 1/3] usb: gadget: Store endpoint pointer in usb_request Sasha Levin
  2025-10-20 16:20   ` [PATCH 5.15.y 2/3] usb: gadget: Introduce free_usb_request helper Sasha Levin
@ 2025-10-20 16:20   ` Sasha Levin
  1 sibling, 0 replies; 5+ messages in thread
From: Sasha Levin @ 2025-10-20 16:20 UTC (permalink / raw)
  To: stable; +Cc: Kuen-Han Tsai, stable, Greg Kroah-Hartman, Sasha Levin

From: Kuen-Han Tsai <khtsai@google.com>

[ Upstream commit 75a5b8d4ddd4eb6b16cb0b475d14ff4ae64295ef ]

After an bind/unbind cycle, the ncm->notify_req is left stale. If a
subsequent bind fails, the unified error label attempts to free this
stale request, leading to a NULL pointer dereference when accessing
ep->ops->free_request.

Refactor the error handling in the bind path to use the __free()
automatic cleanup mechanism.

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
Call trace:
 usb_ep_free_request+0x2c/0xec
 ncm_bind+0x39c/0x3dc
 usb_add_function+0xcc/0x1f0
 configfs_composite_bind+0x468/0x588
 gadget_bind_driver+0x104/0x270
 really_probe+0x190/0x374
 __driver_probe_device+0xa0/0x12c
 driver_probe_device+0x3c/0x218
 __device_attach_driver+0x14c/0x188
 bus_for_each_drv+0x10c/0x168
 __device_attach+0xfc/0x198
 device_initial_probe+0x14/0x24
 bus_probe_device+0x94/0x11c
 device_add+0x268/0x48c
 usb_add_gadget+0x198/0x28c
 dwc3_gadget_init+0x700/0x858
 __dwc3_set_mode+0x3cc/0x664
 process_scheduled_works+0x1d8/0x488
 worker_thread+0x244/0x334
 kthread+0x114/0x1bc
 ret_from_fork+0x10/0x20

Fixes: 9f6ce4240a2b ("usb: gadget: f_ncm.c added")
Cc: stable@kernel.org
Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
Link: https://lore.kernel.org/r/20250916-ready-v1-3-4997bf277548@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250916-ready-v1-3-4997bf277548@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/gadget/function/f_ncm.c | 78 ++++++++++++-----------------
 1 file changed, 33 insertions(+), 45 deletions(-)

diff --git a/drivers/usb/gadget/function/f_ncm.c b/drivers/usb/gadget/function/f_ncm.c
index 00995d65b54c7..4fe6a1efe0986 100644
--- a/drivers/usb/gadget/function/f_ncm.c
+++ b/drivers/usb/gadget/function/f_ncm.c
@@ -11,6 +11,7 @@
  * Copyright (C) 2008 Nokia Corporation
  */
 
+#include <linux/cleanup.h>
 #include <linux/kernel.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
@@ -19,6 +20,7 @@
 #include <linux/crc32.h>
 
 #include <linux/usb/cdc.h>
+#include <linux/usb/gadget.h>
 
 #include "u_ether.h"
 #include "u_ether_configfs.h"
@@ -1441,18 +1443,18 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	struct usb_ep		*ep;
 	struct f_ncm_opts	*ncm_opts;
 
+	struct usb_os_desc_table	*os_desc_table __free(kfree) = NULL;
+	struct usb_request		*request __free(free_usb_request) = NULL;
+
 	if (!can_support_ecm(cdev->gadget))
 		return -EINVAL;
 
 	ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
 
 	if (cdev->use_os_string) {
-		f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
-					   GFP_KERNEL);
-		if (!f->os_desc_table)
+		os_desc_table = kzalloc(sizeof(*os_desc_table), GFP_KERNEL);
+		if (!os_desc_table)
 			return -ENOMEM;
-		f->os_desc_n = 1;
-		f->os_desc_table[0].os_desc = &ncm_opts->ncm_os_desc;
 	}
 
 	mutex_lock(&ncm_opts->lock);
@@ -1462,16 +1464,15 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	mutex_unlock(&ncm_opts->lock);
 
 	if (status)
-		goto fail;
+		return status;
 
 	ncm_opts->bound = true;
 
 	us = usb_gstrings_attach(cdev, ncm_strings,
 				 ARRAY_SIZE(ncm_string_defs));
-	if (IS_ERR(us)) {
-		status = PTR_ERR(us);
-		goto fail;
-	}
+	if (IS_ERR(us))
+		return PTR_ERR(us);
+
 	ncm_control_intf.iInterface = us[STRING_CTRL_IDX].id;
 	ncm_data_nop_intf.iInterface = us[STRING_DATA_IDX].id;
 	ncm_data_intf.iInterface = us[STRING_DATA_IDX].id;
@@ -1481,55 +1482,47 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	/* allocate instance-specific interface IDs */
 	status = usb_interface_id(c, f);
 	if (status < 0)
-		goto fail;
+		return status;
 	ncm->ctrl_id = status;
 	ncm_iad_desc.bFirstInterface = status;
 
 	ncm_control_intf.bInterfaceNumber = status;
 	ncm_union_desc.bMasterInterface0 = status;
 
-	if (cdev->use_os_string)
-		f->os_desc_table[0].if_id =
-			ncm_iad_desc.bFirstInterface;
-
 	status = usb_interface_id(c, f);
 	if (status < 0)
-		goto fail;
+		return status;
 	ncm->data_id = status;
 
 	ncm_data_nop_intf.bInterfaceNumber = status;
 	ncm_data_intf.bInterfaceNumber = status;
 	ncm_union_desc.bSlaveInterface0 = status;
 
-	status = -ENODEV;
-
 	/* allocate instance-specific endpoints */
 	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_in_desc);
 	if (!ep)
-		goto fail;
+		return -ENODEV;
 	ncm->port.in_ep = ep;
 
 	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_out_desc);
 	if (!ep)
-		goto fail;
+		return -ENODEV;
 	ncm->port.out_ep = ep;
 
 	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_notify_desc);
 	if (!ep)
-		goto fail;
+		return -ENODEV;
 	ncm->notify = ep;
 
-	status = -ENOMEM;
-
 	/* allocate notification request and buffer */
-	ncm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
-	if (!ncm->notify_req)
-		goto fail;
-	ncm->notify_req->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
-	if (!ncm->notify_req->buf)
-		goto fail;
-	ncm->notify_req->context = ncm;
-	ncm->notify_req->complete = ncm_notify_complete;
+	request = usb_ep_alloc_request(ep, GFP_KERNEL);
+	if (!request)
+		return -ENOMEM;
+	request->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
+	if (!request->buf)
+		return -ENOMEM;
+	request->context = ncm;
+	request->complete = ncm_notify_complete;
 
 	/*
 	 * support all relevant hardware speeds... we expect that when
@@ -1549,7 +1542,7 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
 			ncm_ss_function, ncm_ss_function);
 	if (status)
-		goto fail;
+		return status;
 
 	/*
 	 * NOTE:  all that is done without knowing or caring about
@@ -1563,25 +1556,20 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 	hrtimer_init(&ncm->task_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
 	ncm->task_timer.function = ncm_tx_timeout;
 
+	if (cdev->use_os_string) {
+		os_desc_table[0].os_desc = &ncm_opts->ncm_os_desc;
+		os_desc_table[0].if_id = ncm_iad_desc.bFirstInterface;
+		f->os_desc_table = no_free_ptr(os_desc_table);
+		f->os_desc_n = 1;
+	}
+        ncm->notify_req = no_free_ptr(request);
+
 	DBG(cdev, "CDC Network: %s speed IN/%s OUT/%s NOTIFY/%s\n",
 			gadget_is_superspeed(c->cdev->gadget) ? "super" :
 			gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
 			ncm->port.in_ep->name, ncm->port.out_ep->name,
 			ncm->notify->name);
 	return 0;
-
-fail:
-	kfree(f->os_desc_table);
-	f->os_desc_n = 0;
-
-	if (ncm->notify_req) {
-		kfree(ncm->notify_req->buf);
-		usb_ep_free_request(ncm->notify, ncm->notify_req);
-	}
-
-	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
-
-	return status;
 }
 
 static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)
-- 
2.51.0


^ permalink raw reply related	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2025-10-20 16:20 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-10-16  9:18 FAILED: patch "[PATCH] usb: gadget: f_ncm: Refactor bind path to use __free()" failed to apply to 5.15-stable tree gregkh
2025-10-20 16:20 ` [PATCH 5.15.y 1/3] usb: gadget: Store endpoint pointer in usb_request Sasha Levin
2025-10-20 16:20   ` [PATCH 5.15.y 2/3] usb: gadget: Introduce free_usb_request helper Sasha Levin
2025-10-20 16:20   ` [PATCH 5.15.y 3/3] usb: gadget: f_ncm: Refactor bind path to use __free() Sasha Levin
  -- strict thread matches above, loose matches on Subject: below --
2025-10-16  9:19 FAILED: patch "[PATCH] usb: gadget: f_acm: Refactor bind path to use __free()" failed to apply to 5.15-stable tree gregkh
2025-10-20 16:19 ` [PATCH 5.15.y 1/3] usb: gadget: Store endpoint pointer in usb_request Sasha Levin

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