AI Trajectory

null

{
  "EnableConfigs": [
    "USB",
    "USB_GADGET",
    "USB_RAW_GADGET",
    "USB_DUMMY_HCD"
  ],
  "FocusSymbols": [
    "gadget_bind",
    "gadget_unbind",
    "raw_ioctl",
    "raw_process_ep0_io",
    "raw_process_ep_io"
  ],
  "Reasoning": "The patch fixes a race condition in the USB Raw Gadget driver between UDC unbind and endpoint IO operations. It introduces a `udc_usage` counter and an `unbind_completion` to ensure that `gadget_unbind` waits for any pending IO to finish before completing the unbind process. This is a functional change in a core driver used for USB emulation and fuzzing, and it is reachable in virtualized environments.",
  "WorthFuzzing": true
}

null

{
  "PatchDiff": "commit 3777842ff8841936764b156439bf4cfcf0c6f3fe\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate:   Wed Jul 29 10:40:02 2026 +0000\n\n    syz-cluster: applied patch under review\n\ndiff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c\nindex 4febf8dac7ca5..bce4f8d3fa63f 100644\n--- a/drivers/usb/gadget/legacy/raw_gadget.c\n+++ b/drivers/usb/gadget/legacy/raw_gadget.c\n@@ -175,6 +175,8 @@ struct raw_dev {\n \tbool\t\t\t\tgadget_registered;\n \tstruct usb_gadget\t\t*gadget;\n \tstruct usb_request\t\t*req;\n+\tint\t\t\t\tudc_usage;\n+\tstruct completion\t\t*unbind_completion;\n \tbool\t\t\t\tep0_in_pending;\n \tbool\t\t\t\tep0_out_pending;\n \tbool\t\t\t\tep0_urb_queued;\n@@ -205,27 +207,13 @@ static struct raw_dev *dev_new(void)\n static void dev_free(struct kref *kref)\n {\n \tstruct raw_dev *dev = container_of(kref, struct raw_dev, count);\n-\tint i;\n \n \tkfree(dev-\u003eudc_name);\n \tkfree(dev-\u003edriver.udc_name);\n \tkfree(dev-\u003edriver.driver.name);\n \tif (dev-\u003edriver_id_number \u003e= 0)\n \t\tida_free(\u0026driver_id_numbers, dev-\u003edriver_id_number);\n-\tif (dev-\u003ereq) {\n-\t\tif (dev-\u003eep0_urb_queued)\n-\t\t\tusb_ep_dequeue(dev-\u003egadget-\u003eep0, dev-\u003ereq);\n-\t\tusb_ep_free_request(dev-\u003egadget-\u003eep0, dev-\u003ereq);\n-\t}\n \traw_event_queue_destroy(\u0026dev-\u003equeue);\n-\tfor (i = 0; i \u003c dev-\u003eeps_num; i++) {\n-\t\tif (dev-\u003eeps[i].state == STATE_EP_DISABLED)\n-\t\t\tcontinue;\n-\t\tusb_ep_disable(dev-\u003eeps[i].ep);\n-\t\tusb_ep_free_request(dev-\u003eeps[i].ep, dev-\u003eeps[i].req);\n-\t\tkfree(dev-\u003eeps[i].ep-\u003edesc);\n-\t\tdev-\u003eeps[i].state = STATE_EP_DISABLED;\n-\t}\n \tkfree(dev);\n }\n \n@@ -316,6 +304,11 @@ static int gadget_bind(struct usb_gadget *gadget,\n \tret = raw_queue_event(dev, USB_RAW_EVENT_CONNECT, 0, NULL);\n \tif (ret \u003c 0) {\n \t\tdev_err(\u0026gadget-\u003edev, \"failed to queue connect event\\n\");\n+\t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\tdev-\u003egadget = NULL;\n+\t\tdev-\u003ereq = NULL;\n+\t\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n+\t\tusb_ep_free_request(gadget-\u003eep0, req);\n \t\tset_gadget_data(gadget, NULL);\n \t\treturn ret;\n \t}\n@@ -328,6 +321,47 @@ static int gadget_bind(struct usb_gadget *gadget,\n static void gadget_unbind(struct usb_gadget *gadget)\n {\n \tstruct raw_dev *dev = get_gadget_data(gadget);\n+\tunsigned long flags;\n+\tDECLARE_COMPLETION_ONSTACK(done);\n+\tint i;\n+\n+\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\tdev-\u003estate = STATE_DEV_FAILED;\n+\n+\tif (dev-\u003eep0_urb_queued) {\n+\t\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n+\t\tusb_ep_dequeue(gadget-\u003eep0, dev-\u003ereq);\n+\t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t}\n+\tfor (i = 0; i \u003c dev-\u003eeps_num; i++) {\n+\t\tif (dev-\u003eeps[i].state == STATE_EP_ENABLED \u0026\u0026 dev-\u003eeps[i].urb_queued) {\n+\t\t\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n+\t\t\tusb_ep_dequeue(dev-\u003eeps[i].ep, dev-\u003eeps[i].req);\n+\t\t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\t}\n+\t}\n+\n+\tif (dev-\u003eudc_usage \u003e 0) {\n+\t\tdev-\u003eunbind_completion = \u0026done;\n+\t\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n+\t\twait_for_completion(\u0026done);\n+\t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t}\n+\tdev-\u003egadget = NULL;\n+\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n+\n+\tfor (i = 0; i \u003c dev-\u003eeps_num; i++) {\n+\t\tif (dev-\u003eeps[i].state == STATE_EP_DISABLED)\n+\t\t\tcontinue;\n+\t\tusb_ep_disable(dev-\u003eeps[i].ep);\n+\t\tusb_ep_free_request(dev-\u003eeps[i].ep, dev-\u003eeps[i].req);\n+\t\tkfree(dev-\u003eeps[i].ep-\u003edesc);\n+\t\tdev-\u003eeps[i].state = STATE_EP_DISABLED;\n+\t}\n+\tif (dev-\u003ereq) {\n+\t\tusb_ep_free_request(gadget-\u003eep0, dev-\u003ereq);\n+\t\tdev-\u003ereq = NULL;\n+\t}\n \n \tset_gadget_data(gadget, NULL);\n \t/* Matches kref_get() in gadget_bind(). */\n@@ -637,11 +671,11 @@ static int raw_ioctl_event_fetch(struct raw_dev *dev, unsigned long value)\n \n \tevent = raw_event_queue_fetch(\u0026dev-\u003equeue);\n \tif (PTR_ERR(event) == -EINTR) {\n-\t\tdev_dbg(\u0026dev-\u003egadget-\u003edev, \"event fetching interrupted\\n\");\n+\t\tdev_dbg(dev-\u003edev, \"event fetching interrupted\\n\");\n \t\treturn -EINTR;\n \t}\n \tif (IS_ERR(event)) {\n-\t\tdev_err(\u0026dev-\u003egadget-\u003edev, \"failed to fetch event\\n\");\n+\t\tdev_err(dev-\u003edev, \"failed to fetch event\\n\");\n \t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n \t\tdev-\u003estate = STATE_DEV_FAILED;\n \t\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n@@ -723,22 +757,37 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io,\n \tdev-\u003ereq-\u003elength = io-\u003elength;\n \tdev-\u003ereq-\u003ezero = usb_raw_io_flags_zero(io-\u003eflags);\n \tdev-\u003eep0_urb_queued = true;\n+\tdev-\u003eudc_usage++;\n \tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n \n \tret = usb_ep_queue(dev-\u003egadget-\u003eep0, dev-\u003ereq, GFP_KERNEL);\n \tif (ret) {\n-\t\tdev_err(\u0026dev-\u003egadget-\u003edev,\n-\t\t\t\t\"fail, usb_ep_queue returned %d\\n\", ret);\n+\t\tdev_err(dev-\u003edev, \"fail, usb_ep_queue returned %d\\n\", ret);\n \t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\tdev-\u003eudc_usage--;\n+\t\tif (!dev-\u003eudc_usage \u0026\u0026 dev-\u003eunbind_completion)\n+\t\t\tcomplete(dev-\u003eunbind_completion);\n \t\tgoto out_queue_failed;\n \t}\n \n \tret = wait_for_completion_interruptible(\u0026dev-\u003eep0_done);\n \tif (ret) {\n-\t\tdev_dbg(\u0026dev-\u003egadget-\u003edev, \"wait interrupted\\n\");\n-\t\tusb_ep_dequeue(dev-\u003egadget-\u003eep0, dev-\u003ereq);\n-\t\twait_for_completion(\u0026dev-\u003eep0_done);\n+\t\tdev_dbg(dev-\u003edev, \"wait interrupted\\n\");\n \t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\tif (dev-\u003estate != STATE_DEV_FAILED \u0026\u0026 dev-\u003egadget) {\n+\t\t\tstruct usb_ep *ep0 = dev-\u003egadget-\u003eep0;\n+\n+\t\t\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n+\n+\t\t\tusb_ep_dequeue(ep0, dev-\u003ereq);\n+\t\t\twait_for_completion(\u0026dev-\u003eep0_done);\n+\n+\t\t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\t} else {\n+\t\t\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n+\t\t\twait_for_completion(\u0026dev-\u003eep0_done);\n+\t\t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\t}\n \t\tif (dev-\u003eep0_status == -ECONNRESET)\n \t\t\tdev-\u003eep0_status = -EINTR;\n \t\tgoto out_interrupted;\n@@ -750,6 +799,9 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io,\n \tret = dev-\u003eep0_status;\n out_queue_failed:\n \tdev-\u003eep0_urb_queued = false;\n+\tdev-\u003eudc_usage--;\n+\tif (!dev-\u003eudc_usage \u0026\u0026 dev-\u003eunbind_completion)\n+\t\tcomplete(dev-\u003eunbind_completion);\n out_unlock:\n \tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n \treturn ret;\n@@ -956,11 +1008,15 @@ static int raw_ioctl_ep_disable(struct raw_dev *dev, unsigned long value)\n \t\tgoto out_unlock;\n \t}\n \tdev-\u003eeps[i].disabling = true;\n+\tdev-\u003eudc_usage++;\n \tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n \n \tusb_ep_disable(dev-\u003eeps[i].ep);\n \n \tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\tdev-\u003eudc_usage--;\n+\tif (!dev-\u003eudc_usage \u0026\u0026 dev-\u003eunbind_completion)\n+\t\tcomplete(dev-\u003eunbind_completion);\n \tusb_ep_free_request(dev-\u003eeps[i].ep, dev-\u003eeps[i].req);\n \tkfree(dev-\u003eeps[i].ep-\u003edesc);\n \tdev-\u003eeps[i].state = STATE_EP_DISABLED;\n@@ -1109,22 +1165,37 @@ static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io,\n \tep-\u003ereq-\u003elength = io-\u003elength;\n \tep-\u003ereq-\u003ezero = usb_raw_io_flags_zero(io-\u003eflags);\n \tep-\u003eurb_queued = true;\n+\tdev-\u003eudc_usage++;\n \tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n \n \tret = usb_ep_queue(ep-\u003eep, ep-\u003ereq, GFP_KERNEL);\n \tif (ret) {\n-\t\tdev_err(\u0026dev-\u003egadget-\u003edev,\n-\t\t\t\t\"fail, usb_ep_queue returned %d\\n\", ret);\n+\t\tdev_err(dev-\u003edev, \"fail, usb_ep_queue returned %d\\n\", ret);\n \t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\tdev-\u003eudc_usage--;\n+\t\tif (!dev-\u003eudc_usage \u0026\u0026 dev-\u003eunbind_completion)\n+\t\t\tcomplete(dev-\u003eunbind_completion);\n \t\tgoto out_queue_failed;\n \t}\n \n \tret = wait_for_completion_interruptible(\u0026done);\n \tif (ret) {\n-\t\tdev_dbg(\u0026dev-\u003egadget-\u003edev, \"wait interrupted\\n\");\n-\t\tusb_ep_dequeue(ep-\u003eep, ep-\u003ereq);\n-\t\twait_for_completion(\u0026done);\n+\t\tdev_dbg(dev-\u003edev, \"wait interrupted\\n\");\n \t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\tif (dev-\u003estate != STATE_DEV_FAILED \u0026\u0026 dev-\u003egadget) {\n+\t\t\tstruct usb_ep *usb_ep = ep-\u003eep;\n+\n+\t\t\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n+\n+\t\t\tusb_ep_dequeue(usb_ep, ep-\u003ereq);\n+\t\t\twait_for_completion(\u0026done);\n+\n+\t\t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\t} else {\n+\t\t\tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n+\t\t\twait_for_completion(\u0026done);\n+\t\t\tspin_lock_irqsave(\u0026dev-\u003elock, flags);\n+\t\t}\n \t\tif (ep-\u003estatus == -ECONNRESET)\n \t\t\tep-\u003estatus = -EINTR;\n \t\tgoto out_interrupted;\n@@ -1136,6 +1207,9 @@ static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io,\n \tret = ep-\u003estatus;\n out_queue_failed:\n \tep-\u003eurb_queued = false;\n+\tdev-\u003eudc_usage--;\n+\tif (!dev-\u003eudc_usage \u0026\u0026 dev-\u003eunbind_completion)\n+\t\tcomplete(dev-\u003eunbind_completion);\n out_unlock:\n \tspin_unlock_irqrestore(\u0026dev-\u003elock, flags);\n \treturn ret;\n"
}

best-expensive

null

{
  "EnableConfigs": [
    "USB",
    "USB_GADGET",
    "USB_RAW_GADGET",
    "USB_DUMMY_HCD"
  ],
  "FocusSymbols": [
    "gadget_bind",
    "gadget_unbind",
    "raw_ioctl",
    "raw_process_ep0_io",
    "raw_process_ep_io"
  ],
  "Reasoning": "The patch fixes a race condition in the USB Raw Gadget driver between UDC unbind and endpoint IO operations. It introduces a `udc_usage` counter and an `unbind_completion` to ensure that `gadget_unbind` waits for any pending IO to finish before completing the unbind process. This is a functional change in a core driver used for USB emulation and fuzzing, and it is reachable in virtualized environments.",
  "WorthFuzzing": true
}

You are an expert Linux kernel maintainer.
Your job is to review a provided patch series and determine
if it makes functional changes to the kernel that should be fuzzed.

IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in
your workspace. Do NOT rely on your internal knowledge of the kernel. You must actively
use your code access tools to examine the actual source code and confirm any assumptions.

Return WorthFuzzing=false if the patch only contains:
- Modifications to Documentation/, Kconfig files, or code comments.
- Purely decorative changes, such as logging (e.g., pr_err, printk) or tracepoints.
- Changes to numeric constants or macros that do not functionally alter execution flow.
- Code paths that are impossible to reach in virtualized environments like GCE or QEMU,
  even when utilizing software-emulated hardware (e.g., usb gadget, mac80211_hwsim).
- Code in vendor-specific PCIe switch, SmartNIC, or GPU drivers (e.g., mlxsw, pds_core, qed,
  ionic, amdgpu) that require physical PCIe hardware cards not emulated in standard QEMU.
- Driver .remove, .shutdown, or pci_unregister_driver teardown callbacks (e.g., igb_remove)
  that are executed only during PCI hot-unplug or sysfs driver unbind operations.

If it modifies reachable core kernel logic, drivers, or architectures, use your code search
tools to verify the code can be executed, then return WorthFuzzing=true.

When returning WorthFuzzing=true, you MUST ALSO:
1. Extract any specific kernel functions that should be heavily fuzzed into FocusSymbols.
   Avoid listing generic hot-path functions to prevent skewed test distributions.
   Prefer non-static, non-inlined API entrypoint functions over internal static helper functions
   (which are inlined by the compiler and do not have distinct symbol addresses).
2. Identify any specific CONFIG_ options required to properly test this new/modified feature.
   Go and look into the Kconfig files and check for ifdefs around the code, do not make assumptions.
   Also check "depends on" lines in Kconfig to include any non-standard parent subsystem configs
   needed for Kbuild to compile the code statically into vmlinux. List them in the EnableConfigs
   output array, and DO NOT add a 'CONFIG_' prefix (e.g., return "NET_IPV4" instead of "CONFIG_NET_IPV4").
Prefer calling several tools at the same time to save round-trips.


Use set-results tool to provide results of the analysis.
It must be called exactly once before the final reply.
Ignore results of this tool.

For your convenience, here is the diff of the changes:
commit 3777842ff8841936764b156439bf4cfcf0c6f3fe
Author: syz-cluster <triage@syzkaller.com>
Date:   Wed Jul 29 10:40:02 2026 +0000

    syz-cluster: applied patch under review

diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c
index 4febf8dac7ca5..bce4f8d3fa63f 100644
--- a/drivers/usb/gadget/legacy/raw_gadget.c
+++ b/drivers/usb/gadget/legacy/raw_gadget.c
@@ -175,6 +175,8 @@ struct raw_dev {
 	bool				gadget_registered;
 	struct usb_gadget		*gadget;
 	struct usb_request		*req;
+	int				udc_usage;
+	struct completion		*unbind_completion;
 	bool				ep0_in_pending;
 	bool				ep0_out_pending;
 	bool				ep0_urb_queued;
@@ -205,27 +207,13 @@ static struct raw_dev *dev_new(void)
 static void dev_free(struct kref *kref)
 {
 	struct raw_dev *dev = container_of(kref, struct raw_dev, count);
-	int i;
 
 	kfree(dev->udc_name);
 	kfree(dev->driver.udc_name);
 	kfree(dev->driver.driver.name);
 	if (dev->driver_id_number >= 0)
 		ida_free(&driver_id_numbers, dev->driver_id_number);
-	if (dev->req) {
-		if (dev->ep0_urb_queued)
-			usb_ep_dequeue(dev->gadget->ep0, dev->req);
-		usb_ep_free_request(dev->gadget->ep0, dev->req);
-	}
 	raw_event_queue_destroy(&dev->queue);
-	for (i = 0; i < dev->eps_num; i++) {
-		if (dev->eps[i].state == STATE_EP_DISABLED)
-			continue;
-		usb_ep_disable(dev->eps[i].ep);
-		usb_ep_free_request(dev->eps[i].ep, dev->eps[i].req);
-		kfree(dev->eps[i].ep->desc);
-		dev->eps[i].state = STATE_EP_DISABLED;
-	}
 	kfree(dev);
 }
 
@@ -316,6 +304,11 @@ static int gadget_bind(struct usb_gadget *gadget,
 	ret = raw_queue_event(dev, USB_RAW_EVENT_CONNECT, 0, NULL);
 	if (ret < 0) {
 		dev_err(&gadget->dev, "failed to queue connect event\n");
+		spin_lock_irqsave(&dev->lock, flags);
+		dev->gadget = NULL;
+		dev->req = NULL;
+		spin_unlock_irqrestore(&dev->lock, flags);
+		usb_ep_free_request(gadget->ep0, req);
 		set_gadget_data(gadget, NULL);
 		return ret;
 	}
@@ -328,6 +321,47 @@ static int gadget_bind(struct usb_gadget *gadget,
 static void gadget_unbind(struct usb_gadget *gadget)
 {
 	struct raw_dev *dev = get_gadget_data(gadget);
+	unsigned long flags;
+	DECLARE_COMPLETION_ONSTACK(done);
+	int i;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	dev->state = STATE_DEV_FAILED;
+
+	if (dev->ep0_urb_queued) {
+		spin_unlock_irqrestore(&dev->lock, flags);
+		usb_ep_dequeue(gadget->ep0, dev->req);
+		spin_lock_irqsave(&dev->lock, flags);
+	}
+	for (i = 0; i < dev->eps_num; i++) {
+		if (dev->eps[i].state == STATE_EP_ENABLED && dev->eps[i].urb_queued) {
+			spin_unlock_irqrestore(&dev->lock, flags);
+			usb_ep_dequeue(dev->eps[i].ep, dev->eps[i].req);
+			spin_lock_irqsave(&dev->lock, flags);
+		}
+	}
+
+	if (dev->udc_usage > 0) {
+		dev->unbind_completion = &done;
+		spin_unlock_irqrestore(&dev->lock, flags);
+		wait_for_completion(&done);
+		spin_lock_irqsave(&dev->lock, flags);
+	}
+	dev->gadget = NULL;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	for (i = 0; i < dev->eps_num; i++) {
+		if (dev->eps[i].state == STATE_EP_DISABLED)
+			continue;
+		usb_ep_disable(dev->eps[i].ep);
+		usb_ep_free_request(dev->eps[i].ep, dev->eps[i].req);
+		kfree(dev->eps[i].ep->desc);
+		dev->eps[i].state = STATE_EP_DISABLED;
+	}
+	if (dev->req) {
+		usb_ep_free_request(gadget->ep0, dev->req);
+		dev->req = NULL;
+	}
 
 	set_gadget_data(gadget, NULL);
 	/* Matches kref_get() in gadget_bind(). */
@@ -637,11 +671,11 @@ static int raw_ioctl_event_fetch(struct raw_dev *dev, unsigned long value)
 
 	event = raw_event_queue_fetch(&dev->queue);
 	if (PTR_ERR(event) == -EINTR) {
-		dev_dbg(&dev->gadget->dev, "event fetching interrupted\n");
+		dev_dbg(dev->dev, "event fetching interrupted\n");
 		return -EINTR;
 	}
 	if (IS_ERR(event)) {
-		dev_err(&dev->gadget->dev, "failed to fetch event\n");
+		dev_err(dev->dev, "failed to fetch event\n");
 		spin_lock_irqsave(&dev->lock, flags);
 		dev->state = STATE_DEV_FAILED;
 		spin_unlock_irqrestore(&dev->lock, flags);
@@ -723,22 +757,37 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io,
 	dev->req->length = io->length;
 	dev->req->zero = usb_raw_io_flags_zero(io->flags);
 	dev->ep0_urb_queued = true;
+	dev->udc_usage++;
 	spin_unlock_irqrestore(&dev->lock, flags);
 
 	ret = usb_ep_queue(dev->gadget->ep0, dev->req, GFP_KERNEL);
 	if (ret) {
-		dev_err(&dev->gadget->dev,
-				"fail, usb_ep_queue returned %d\n", ret);
+		dev_err(dev->dev, "fail, usb_ep_queue returned %d\n", ret);
 		spin_lock_irqsave(&dev->lock, flags);
+		dev->udc_usage--;
+		if (!dev->udc_usage && dev->unbind_completion)
+			complete(dev->unbind_completion);
 		goto out_queue_failed;
 	}
 
 	ret = wait_for_completion_interruptible(&dev->ep0_done);
 	if (ret) {
-		dev_dbg(&dev->gadget->dev, "wait interrupted\n");
-		usb_ep_dequeue(dev->gadget->ep0, dev->req);
-		wait_for_completion(&dev->ep0_done);
+		dev_dbg(dev->dev, "wait interrupted\n");
 		spin_lock_irqsave(&dev->lock, flags);
+		if (dev->state != STATE_DEV_FAILED && dev->gadget) {
+			struct usb_ep *ep0 = dev->gadget->ep0;
+
+			spin_unlock_irqrestore(&dev->lock, flags);
+
+			usb_ep_dequeue(ep0, dev->req);
+			wait_for_completion(&dev->ep0_done);
+
+			spin_lock_irqsave(&dev->lock, flags);
+		} else {
+			spin_unlock_irqrestore(&dev->lock, flags);
+			wait_for_completion(&dev->ep0_done);
+			spin_lock_irqsave(&dev->lock, flags);
+		}
 		if (dev->ep0_status == -ECONNRESET)
 			dev->ep0_status = -EINTR;
 		goto out_interrupted;
@@ -750,6 +799,9 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io,
 	ret = dev->ep0_status;
 out_queue_failed:
 	dev->ep0_urb_queued = false;
+	dev->udc_usage--;
+	if (!dev->udc_usage && dev->unbind_completion)
+		complete(dev->unbind_completion);
 out_unlock:
 	spin_unlock_irqrestore(&dev->lock, flags);
 	return ret;
@@ -956,11 +1008,15 @@ static int raw_ioctl_ep_disable(struct raw_dev *dev, unsigned long value)
 		goto out_unlock;
 	}
 	dev->eps[i].disabling = true;
+	dev->udc_usage++;
 	spin_unlock_irqrestore(&dev->lock, flags);
 
 	usb_ep_disable(dev->eps[i].ep);
 
 	spin_lock_irqsave(&dev->lock, flags);
+	dev->udc_usage--;
+	if (!dev->udc_usage && dev->unbind_completion)
+		complete(dev->unbind_completion);
 	usb_ep_free_request(dev->eps[i].ep, dev->eps[i].req);
 	kfree(dev->eps[i].ep->desc);
 	dev->eps[i].state = STATE_EP_DISABLED;
@@ -1109,22 +1165,37 @@ static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io,
 	ep->req->length = io->length;
 	ep->req->zero = usb_raw_io_flags_zero(io->flags);
 	ep->urb_queued = true;
+	dev->udc_usage++;
 	spin_unlock_irqrestore(&dev->lock, flags);
 
 	ret = usb_ep_queue(ep->ep, ep->req, GFP_KERNEL);
 	if (ret) {
-		dev_err(&dev->gadget->dev,
-				"fail, usb_ep_queue returned %d\n", ret);
+		dev_err(dev->dev, "fail, usb_ep_queue returned %d\n", ret);
 		spin_lock_irqsave(&dev->lock, flags);
+		dev->udc_usage--;
+		if (!dev->udc_usage && dev->unbind_completion)
+			complete(dev->unbind_completion);
 		goto out_queue_failed;
 	}
 
 	ret = wait_for_completion_interruptible(&done);
 	if (ret) {
-		dev_dbg(&dev->gadget->dev, "wait interrupted\n");
-		usb_ep_dequeue(ep->ep, ep->req);
-		wait_for_completion(&done);
+		dev_dbg(dev->dev, "wait interrupted\n");
 		spin_lock_irqsave(&dev->lock, flags);
+		if (dev->state != STATE_DEV_FAILED && dev->gadget) {
+			struct usb_ep *usb_ep = ep->ep;
+
+			spin_unlock_irqrestore(&dev->lock, flags);
+
+			usb_ep_dequeue(usb_ep, ep->req);
+			wait_for_completion(&done);
+
+			spin_lock_irqsave(&dev->lock, flags);
+		} else {
+			spin_unlock_irqrestore(&dev->lock, flags);
+			wait_for_completion(&done);
+			spin_lock_irqsave(&dev->lock, flags);
+		}
 		if (ep->status == -ECONNRESET)
 			ep->status = -EINTR;
 		goto out_interrupted;
@@ -1136,6 +1207,9 @@ static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io,
 	ret = ep->status;
 out_queue_failed:
 	ep->urb_queued = false;
+	dev->udc_usage--;
+	if (!dev->udc_usage && dev->unbind_completion)
+		complete(dev->unbind_completion);
 out_unlock:
 	spin_unlock_irqrestore(&dev->lock, flags);
 	return ret;

gemini-3.1-pro-preview

null

null

							input: 5201
							output: 35
							thoughts: 415
						

**Analyzing a USB Raw Gadget Patch for Fuzzing Potential**

Okay, so I'm looking at a patch for `drivers/usb/gadget/legacy/raw_gadget.c`. This is the USB Raw Gadget driver, which rings a bell – it's the one we use for emulating USB devices from userspace, specifically crucial for syzkaller's fuzzing efforts. The patch seems to be adding `udc_usage` and `unbind_completion` to `struct raw_dev`. It's tweaking `gadget_unbind` to ensure it properly waits for UDC usage to drop before unbinding and cleans up URBs correctly. I see modifications in `raw_process_ep0_io`, `raw_ioctl_ep_disable`, and `raw_process_ep_io` related to tracking `udc_usage` and completing `unbind_completion`. Plus, some fixes for those `dev_err` and `dev_dbg` calls, making sure they use `dev->dev` instead of `dev->gadget->dev` because `dev->gadget` can be null during the unbind process.

Hang on... the real question is whether this is reachable in a virtualized environment like QEMU or GCE. This is critical for fuzzing! Oh, right, the USB Raw Gadget is *designed* for precisely this use case. Syzkaller leverages it in virtualized environments. The prompt, remember, is asking me to return WorthFuzzing=false if the code paths are impossible to reach in virtualized environments *even* with software-emulated hardware. But this *is* software-emulated hardware! The prompt says "even when utilizing software-emulated hardware," meaning that if it is impossible to reach *even with* software-emulated hardware, then it's false. But this *is* the software-emulated hardware, so it is reachable.

So this looks promising. I need to take a quick look at the Kconfig for `drivers/usb/gadget/legacy/raw_gadget.c` to confirm it is enabled, but from the sound of it, this looks like a definite "WorthFuzzing=true."

{
  "Expression": "raw_gadget",
  "PathPrefix": "drivers/usb/gadget/legacy/Kconfig"
}

{
  "Output": "drivers/usb/gadget/legacy/Kconfig=516=config USB_RAW_GADGET\n--\ndrivers/usb/gadget/legacy/Kconfig-529-\t  Say \"y\" to link the driver statically, or \"m\" to build a\ndrivers/usb/gadget/legacy/Kconfig:530:\t  dynamically linked module called \"raw_gadget\".\ndrivers/usb/gadget/legacy/Kconfig-531-\n"
}

gemini-3.1-pro-preview

null

null

							input: 6242
							output: 38
							thoughts: 23
						

Okay, here's my take on those thoughts, tailored for an expert audience:

**Analyzing the USB Raw Gadget Configuration**

Alright, so we're talking about `CONFIG_USB_RAW_GADGET`. That's the key configuration setting we're focused on here. My first instinct, as always, is to dive into the dependencies. Understanding *how* `CONFIG_USB_RAW_GADGET` relates to other kernel components is absolutely crucial. We need to trace its connections to other USB gadget drivers, the core USB subsystem, and potentially even device tree configuration. Knowing its dependencies will tell me everything from what it needs to function to the potential side effects of enabling or disabling it. This will inform my assessment of its suitability for the intended use-case and if enabling it will cause any conflicts with other system configurations. My brain is already running through possible dependency paths and thinking about the implications for my current project. Let's dig in and see what we find.

{
  "Expression": "config USB_RAW_GADGET",
  "PathPrefix": "drivers/usb/gadget/legacy/Kconfig"
}

{
  "Output": "drivers/usb/gadget/legacy/Kconfig=501=config USB_G_WEBCAM\n--\ndrivers/usb/gadget/legacy/Kconfig-515-\ndrivers/usb/gadget/legacy/Kconfig:516:config USB_RAW_GADGET\ndrivers/usb/gadget/legacy/Kconfig-517-\ttristate \"USB Raw Gadget\"\n"
}

gemini-3.1-pro-preview

null

null

							input: 6613
							output: 39
							thoughts: 14
						

Here's my attempt at summarizing the thought process, tailored for an expert audience:

**Diving into the Kconfig - Line 516**

Okay, let's get down to brass tacks. Based on the current trajectory of this investigation, I need a deeper understanding of how this feature is controlled and configured. Line 516 in the Kconfig file has come up as a likely point of interest, so I'm going to start there. I'm not just looking for a specific variable, but the context around it: the dependencies, the relationships to other configurations, and the overall conditional logic. I want to build a complete mental model of this section of the config and see what decisions it drives. It is crucial to have a clear understanding of what influences the configuration and make sure there are no obvious misconfigurations.

{
  "File": "drivers/usb/gadget/legacy/Kconfig",
  "FirstLine": 510,
  "LineCount": 20
}

{
  "Contents": " 510:\t\t  device. It provides a userspace API to process UVC control requests\n 511:\t\t  and stream video data to the host.\n 512:\t\n 513:\t\t  Say \"y\" to link the driver statically, or \"m\" to build a\n 514:\t\t  dynamically linked module called \"g_webcam\".\n 515:\t\n 516:\tconfig USB_RAW_GADGET\n 517:\t\ttristate \"USB Raw Gadget\"\n 518:\t\thelp\n 519:\t\t  USB Raw Gadget is a gadget driver that gives userspace low-level\n 520:\t\t  control over the gadget's communication process.\n 521:\t\n 522:\t\t  Like any other gadget driver, Raw Gadget implements USB devices via\n 523:\t\t  the USB gadget API. Unlike most gadget drivers, Raw Gadget does not\n 524:\t\t  implement any concrete USB functions itself but requires userspace\n 525:\t\t  to do that.\n 526:\t\n 527:\t\t  See Documentation/usb/raw-gadget.rst for details.\n 528:\t\n 529:\t\t  Say \"y\" to link the driver statically, or \"m\" to build a\n"
}

gemini-3.1-pro-preview

null

null

							input: 7169
							output: 35
							thoughts: 27
						

Here's my attempt at summarizing the thought process, tailored for an expert audience:

**Investigating Dependency Declarations**

Alright, I was expecting to see a clear `depends on` declaration, but it's absent. That's a bit unusual; good project organization, especially in larger systems, *relies* on explicitly stated dependencies for clarity and maintainability. My first instinct is to scan the file's header or perhaps the project configuration menus. Hopefully, the dependency information is located within the same file or a neighboring configuration file, or perhaps the IDE has some hidden navigation options. It's a bit of an assumption, but it's always worth checking the obvious places first, before I go digging deeper into the code or the build system.

{
  "Expression": "menuconfig USB_GADGET",
  "PathPrefix": "drivers/usb/gadget/Kconfig"
}

{
  "Output": "drivers/usb/gadget/Kconfig-16-\ndrivers/usb/gadget/Kconfig:17:menuconfig USB_GADGET\ndrivers/usb/gadget/Kconfig-18-\ttristate \"USB Gadget Support\"\n"
}

gemini-3.1-pro-preview

null

null

							input: 7458
							output: 37
							thoughts: 21
						

Here's my take on the thought process:

**Diving into the USB Gadget Legacy Kconfig**

Alright, let's get down to brass tacks. I need to understand the specifics of this "legacy" USB gadget configuration. My first move is to jump right into the `drivers/usb/gadget/legacy/Kconfig` file. That's the key to understanding the context of these legacy options. I know that by examining the configuration file, I should get a better picture of what's controlled by it, dependencies that it has, and perhaps even the rationale behind its existence. I need to understand what's *legacy* about it. Let's see what we can find.

{
  "File": "drivers/usb/gadget/legacy/Kconfig",
  "FirstLine": 1,
  "LineCount": 20
}

{
  "Contents": "   1:\t# SPDX-License-Identifier: GPL-2.0\n   2:\t#\n   3:\t# USB Gadget support on a system involves\n   4:\t#    (a) a peripheral controller, and\n   5:\t#    (b) the gadget driver using it.\n   6:\t#\n   7:\t# NOTE:  Gadget support ** DOES NOT ** depend on host-side CONFIG_USB !!\n   8:\t#\n   9:\t#  - Host systems (like PCs) need CONFIG_USB (with \"A\" jacks).\n  10:\t#  - Peripherals (like PDAs) need CONFIG_USB_GADGET (with \"B\" jacks).\n  11:\t#  - Some systems have both kinds of controllers.\n  12:\t#\n  13:\t# With help from a special transceiver and a \"Mini-AB\" jack, systems with\n  14:\t# both kinds of controller can also support \"USB On-the-Go\" (CONFIG_USB_OTG).\n  15:\t#\n  16:\t# A Linux \"Gadget Driver\" talks to the USB Peripheral Controller\n  17:\t# driver through the abstract \"gadget\" API.  Some other operating\n  18:\t# systems call these \"client\" drivers, of which \"class drivers\"\n  19:\t# are a subset (implementing a USB device class specification).\n  20:\t# A gadget driver implements one or more USB functions using\n"
}

gemini-3.1-pro-preview

null

null

							input: 8021
							output: 33
							thoughts: 28
						

Okay, here's my interpretation of those thoughts, framed as an expert's internal monologue:

**Focusing on USB Gadget Configuration**

Alright, so we're diving into the USB gadget configuration here. My immediate focus is on `USB_GADGET` – that's the primary, overarching option. It's the big picture. Before I proceed, I need to double-check the dependencies of `USB_RAW_GADGET`. It's crucial to understand how that specific option fits within the larger gadget framework, ensuring no critical dependencies are overlooked. Let's make sure everything is in place for a proper build and functionality.

{
  "Expression": "depends on",
  "PathPrefix": "drivers/usb/gadget/legacy/Kconfig"
}

{
  "Output": "drivers/usb/gadget/legacy/Kconfig=65=config USB_ZERO_HNPTEST\ndrivers/usb/gadget/legacy/Kconfig-66-\tbool \"HNP Test Device\"\ndrivers/usb/gadget/legacy/Kconfig:67:\tdepends on USB_ZERO \u0026\u0026 USB_OTG\ndrivers/usb/gadget/legacy/Kconfig-68-\thelp\n--\ndrivers/usb/gadget/legacy/Kconfig=75=config USB_AUDIO\ndrivers/usb/gadget/legacy/Kconfig-76-\ttristate \"Audio Gadget\"\ndrivers/usb/gadget/legacy/Kconfig:77:\tdepends on SND\ndrivers/usb/gadget/legacy/Kconfig-78-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=100=config GADGET_UAC1\ndrivers/usb/gadget/legacy/Kconfig-101-\tbool \"UAC 1.0\"\ndrivers/usb/gadget/legacy/Kconfig:102:\tdepends on USB_AUDIO\ndrivers/usb/gadget/legacy/Kconfig-103-\thelp\n--\ndrivers/usb/gadget/legacy/Kconfig=107=config GADGET_UAC1_LEGACY\ndrivers/usb/gadget/legacy/Kconfig-108-\tbool \"UAC 1.0 (Legacy)\"\ndrivers/usb/gadget/legacy/Kconfig:109:\tdepends on GADGET_UAC1\ndrivers/usb/gadget/legacy/Kconfig-110-\thelp\n--\ndrivers/usb/gadget/legacy/Kconfig=115=config USB_ETH\ndrivers/usb/gadget/legacy/Kconfig-116-\ttristate \"Ethernet Gadget (with CDC Ethernet support)\"\ndrivers/usb/gadget/legacy/Kconfig:117:\tdepends on NET\ndrivers/usb/gadget/legacy/Kconfig-118-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig-140-\t  Within the USB device, this gadget driver exposes a network device\ndrivers/usb/gadget/legacy/Kconfig:141:\t  \"usbX\", where X depends on what other networking devices you have.\ndrivers/usb/gadget/legacy/Kconfig-142-\t  Treat it like a two-node Ethernet link:  host, and gadget.\n--\ndrivers/usb/gadget/legacy/Kconfig=153=config USB_ETH_RNDIS\ndrivers/usb/gadget/legacy/Kconfig-154-\tbool \"RNDIS support\"\ndrivers/usb/gadget/legacy/Kconfig:155:\tdepends on USB_ETH\ndrivers/usb/gadget/legacy/Kconfig-156-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=173=config USB_ETH_EEM\ndrivers/usb/gadget/legacy/Kconfig-174-\tbool \"Ethernet Emulation Model (EEM) support\"\ndrivers/usb/gadget/legacy/Kconfig:175:\tdepends on USB_ETH\ndrivers/usb/gadget/legacy/Kconfig-176-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=190=config USB_G_NCM\ndrivers/usb/gadget/legacy/Kconfig-191-\ttristate \"Network Control Model (NCM) support\"\ndrivers/usb/gadget/legacy/Kconfig:192:\tdepends on NET\ndrivers/usb/gadget/legacy/Kconfig-193-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=237=config USB_FUNCTIONFS_ETH\ndrivers/usb/gadget/legacy/Kconfig-238-\tbool \"Include configuration with CDC ECM (Ethernet)\"\ndrivers/usb/gadget/legacy/Kconfig:239:\tdepends on USB_FUNCTIONFS \u0026\u0026 NET\ndrivers/usb/gadget/legacy/Kconfig-240-\tselect USB_U_ETHER\n--\ndrivers/usb/gadget/legacy/Kconfig=247=config USB_FUNCTIONFS_RNDIS\ndrivers/usb/gadget/legacy/Kconfig-248-\tbool \"Include configuration with RNDIS (Ethernet)\"\ndrivers/usb/gadget/legacy/Kconfig:249:\tdepends on USB_FUNCTIONFS \u0026\u0026 NET\ndrivers/usb/gadget/legacy/Kconfig-250-\tselect USB_U_ETHER\n--\ndrivers/usb/gadget/legacy/Kconfig=255=config USB_FUNCTIONFS_GENERIC\ndrivers/usb/gadget/legacy/Kconfig-256-\tbool \"Include 'pure' configuration\"\ndrivers/usb/gadget/legacy/Kconfig:257:\tdepends on USB_FUNCTIONFS\ndrivers/usb/gadget/legacy/Kconfig-258-\thelp\n--\ndrivers/usb/gadget/legacy/Kconfig=262=config USB_MASS_STORAGE\ndrivers/usb/gadget/legacy/Kconfig-263-\ttristate \"Mass Storage Gadget\"\ndrivers/usb/gadget/legacy/Kconfig:264:\tdepends on BLOCK\ndrivers/usb/gadget/legacy/Kconfig-265-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=279=config USB_GADGET_TARGET\ndrivers/usb/gadget/legacy/Kconfig-280-\ttristate \"USB Gadget Target Fabric Module\"\ndrivers/usb/gadget/legacy/Kconfig:281:\tdepends on TARGET_CORE\ndrivers/usb/gadget/legacy/Kconfig-282-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=291=config USB_G_SERIAL\ndrivers/usb/gadget/legacy/Kconfig-292-\ttristate \"Serial Gadget (with CDC ACM and CDC OBEX support)\"\ndrivers/usb/gadget/legacy/Kconfig:293:\tdepends on TTY\ndrivers/usb/gadget/legacy/Kconfig-294-\tselect USB_U_SERIAL\n--\ndrivers/usb/gadget/legacy/Kconfig=316=config USB_MIDI_GADGET\ndrivers/usb/gadget/legacy/Kconfig-317-\ttristate \"MIDI Gadget\"\ndrivers/usb/gadget/legacy/Kconfig:318:\tdepends on SND\ndrivers/usb/gadget/legacy/Kconfig-319-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=351=config USB_CDC_COMPOSITE\ndrivers/usb/gadget/legacy/Kconfig-352-\ttristate \"CDC Composite Device (Ethernet and ACM)\"\ndrivers/usb/gadget/legacy/Kconfig:353:\tdepends on NET\ndrivers/usb/gadget/legacy/Kconfig-354-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=370=config USB_G_NOKIA\ndrivers/usb/gadget/legacy/Kconfig-371-\ttristate \"Nokia composite gadget\"\ndrivers/usb/gadget/legacy/Kconfig:372:\tdepends on PHONET\ndrivers/usb/gadget/legacy/Kconfig:373:\tdepends on BLOCK\ndrivers/usb/gadget/legacy/Kconfig-374-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=389=config USB_G_ACM_MS\ndrivers/usb/gadget/legacy/Kconfig-390-\ttristate \"CDC Composite Device (ACM and mass storage)\"\ndrivers/usb/gadget/legacy/Kconfig:391:\tdepends on BLOCK\ndrivers/usb/gadget/legacy/Kconfig-392-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=403=config USB_G_MULTI\ndrivers/usb/gadget/legacy/Kconfig-404-\ttristate \"Multifunction Composite Gadget\"\ndrivers/usb/gadget/legacy/Kconfig:405:\tdepends on BLOCK \u0026\u0026 NET\ndrivers/usb/gadget/legacy/Kconfig-406-\tselect USB_G_MULTI_CDC if !USB_G_MULTI_RNDIS\n--\ndrivers/usb/gadget/legacy/Kconfig=427=config USB_G_MULTI_RNDIS\ndrivers/usb/gadget/legacy/Kconfig-428-\tbool \"RNDIS + CDC Serial + Storage configuration\"\ndrivers/usb/gadget/legacy/Kconfig:429:\tdepends on USB_G_MULTI\ndrivers/usb/gadget/legacy/Kconfig-430-\tselect USB_F_RNDIS\n--\ndrivers/usb/gadget/legacy/Kconfig=440=config USB_G_MULTI_CDC\ndrivers/usb/gadget/legacy/Kconfig-441-\tbool \"CDC Ethernet + CDC Serial + Storage configuration\"\ndrivers/usb/gadget/legacy/Kconfig:442:\tdepends on USB_G_MULTI\ndrivers/usb/gadget/legacy/Kconfig-443-\tselect USB_F_ECM\n--\ndrivers/usb/gadget/legacy/Kconfig=468=config USB_G_DBGP\ndrivers/usb/gadget/legacy/Kconfig-469-\ttristate \"EHCI Debug Device Gadget\"\ndrivers/usb/gadget/legacy/Kconfig:470:\tdepends on TTY\ndrivers/usb/gadget/legacy/Kconfig-471-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/legacy/Kconfig=484=config USB_G_DBGP_PRINTK\ndrivers/usb/gadget/legacy/Kconfig:485:\tdepends on USB_G_DBGP\ndrivers/usb/gadget/legacy/Kconfig-486-\tbool \"printk\"\n--\ndrivers/usb/gadget/legacy/Kconfig=490=config USB_G_DBGP_SERIAL\ndrivers/usb/gadget/legacy/Kconfig:491:\tdepends on USB_G_DBGP\ndrivers/usb/gadget/legacy/Kconfig-492-\tselect USB_U_SERIAL\n--\ndrivers/usb/gadget/legacy/Kconfig=501=config USB_G_WEBCAM\ndrivers/usb/gadget/legacy/Kconfig-502-\ttristate \"USB Webcam Gadget\"\ndrivers/usb/gadget/legacy/Kconfig:503:\tdepends on VIDEO_DEV\ndrivers/usb/gadget/legacy/Kconfig-504-\tselect USB_LIBCOMPOSITE\n"
}

gemini-3.1-pro-preview

null

null

							input: 10857
							output: 31
							thoughts: 71
						

**Analyzing USB Gadget Configuration**

Okay, so I'm looking at this `USB_RAW_GADGET` option, and it's interesting. Directly, it doesn't seem to have any explicit dependencies declared in the Kconfig files, but it's nested within the `menuconfig USB_GADGET` block. Therefore, it implicitly *does* depend on `USB_GADGET`. That makes sense; it's a child configuration option.

Now, a further question arises. Does `USB_GADGET` itself rely on a broader support framework like `USB_SUPPORT`? To get a clear picture of its dependencies, the next logical step is to dive into the `drivers/usb/gadget/Kconfig` file. I'll need to examine that file to fully understand the relationships and what conditions need to be met for these options to be available.

{
  "Expression": "depends on",
  "PathPrefix": "drivers/usb/gadget/Kconfig"
}

{
  "Output": "drivers/usb/gadget/Kconfig=49=config USB_GADGET_DEBUG\ndrivers/usb/gadget/Kconfig-50-\tbool \"Debugging messages (DEVELOPMENT)\"\ndrivers/usb/gadget/Kconfig:51:\tdepends on DEBUG_KERNEL\ndrivers/usb/gadget/Kconfig-52-\thelp\n--\ndrivers/usb/gadget/Kconfig=63=config USB_GADGET_VERBOSE\ndrivers/usb/gadget/Kconfig-64-\tbool \"Verbose debugging Messages (DEVELOPMENT)\"\ndrivers/usb/gadget/Kconfig:65:\tdepends on USB_GADGET_DEBUG\ndrivers/usb/gadget/Kconfig-66-\thelp\n--\ndrivers/usb/gadget/Kconfig=77=config USB_GADGET_DEBUG_FILES\ndrivers/usb/gadget/Kconfig-78-\tbool \"Debugging information files (DEVELOPMENT)\"\ndrivers/usb/gadget/Kconfig:79:\tdepends on PROC_FS\ndrivers/usb/gadget/Kconfig-80-\thelp\n--\ndrivers/usb/gadget/Kconfig=88=config USB_GADGET_DEBUG_FS\ndrivers/usb/gadget/Kconfig-89-\tbool \"Debugging information files in debugfs (DEVELOPMENT)\"\ndrivers/usb/gadget/Kconfig:90:\tdepends on DEBUG_FS\ndrivers/usb/gadget/Kconfig-91-\thelp\n--\ndrivers/usb/gadget/Kconfig=132=config U_SERIAL_CONSOLE\ndrivers/usb/gadget/Kconfig-133-\tbool \"Serial gadget console support\"\ndrivers/usb/gadget/Kconfig:134:\tdepends on USB_U_SERIAL\ndrivers/usb/gadget/Kconfig-135-\thelp\n--\ndrivers/usb/gadget/Kconfig=145=config USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/Kconfig-147-\tselect CONFIGFS_FS\ndrivers/usb/gadget/Kconfig:148:\tdepends on USB_GADGET\ndrivers/usb/gadget/Kconfig-149-\n--\ndrivers/usb/gadget/Kconfig=240=config USB_CONFIGFS_SERIAL\ndrivers/usb/gadget/Kconfig-241-\tbool \"Generic serial bulk in/out\"\ndrivers/usb/gadget/Kconfig:242:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:243:\tdepends on TTY\ndrivers/usb/gadget/Kconfig-244-\tselect USB_U_SERIAL\n--\ndrivers/usb/gadget/Kconfig=249=config USB_CONFIGFS_ACM\ndrivers/usb/gadget/Kconfig-250-\tbool \"Abstract Control Model (CDC ACM)\"\ndrivers/usb/gadget/Kconfig:251:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:252:\tdepends on TTY\ndrivers/usb/gadget/Kconfig-253-\tselect USB_U_SERIAL\n--\ndrivers/usb/gadget/Kconfig=259=config USB_CONFIGFS_OBEX\ndrivers/usb/gadget/Kconfig-260-\tbool \"Object Exchange Model (CDC OBEX)\"\ndrivers/usb/gadget/Kconfig:261:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:262:\tdepends on TTY\ndrivers/usb/gadget/Kconfig-263-\tselect USB_U_SERIAL\n--\ndrivers/usb/gadget/Kconfig=269=config USB_CONFIGFS_NCM\ndrivers/usb/gadget/Kconfig-270-\tbool \"Network Control Model (CDC NCM)\"\ndrivers/usb/gadget/Kconfig:271:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:272:\tdepends on NET\ndrivers/usb/gadget/Kconfig-273-\tselect USB_U_ETHER\n--\ndrivers/usb/gadget/Kconfig=281=config USB_CONFIGFS_ECM\ndrivers/usb/gadget/Kconfig-282-\tbool \"Ethernet Control Model (CDC ECM)\"\ndrivers/usb/gadget/Kconfig:283:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:284:\tdepends on NET\ndrivers/usb/gadget/Kconfig-285-\tselect USB_U_ETHER\n--\ndrivers/usb/gadget/Kconfig=293=config USB_CONFIGFS_ECM_SUBSET\ndrivers/usb/gadget/Kconfig-294-\tbool \"Ethernet Control Model (CDC ECM) subset\"\ndrivers/usb/gadget/Kconfig:295:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:296:\tdepends on NET\ndrivers/usb/gadget/Kconfig-297-\tselect USB_U_ETHER\n--\ndrivers/usb/gadget/Kconfig=303=config USB_CONFIGFS_RNDIS\ndrivers/usb/gadget/Kconfig-304-\tbool \"RNDIS\"\ndrivers/usb/gadget/Kconfig:305:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:306:\tdepends on NET\ndrivers/usb/gadget/Kconfig-307-\tselect USB_U_ETHER\n--\ndrivers/usb/gadget/Kconfig=319=config USB_CONFIGFS_EEM\ndrivers/usb/gadget/Kconfig-320-\tbool \"Ethernet Emulation Model (EEM)\"\ndrivers/usb/gadget/Kconfig:321:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:322:\tdepends on NET\ndrivers/usb/gadget/Kconfig-323-\tselect USB_U_ETHER\n--\ndrivers/usb/gadget/Kconfig=335=config USB_CONFIGFS_PHONET\ndrivers/usb/gadget/Kconfig-336-\tbool \"Phonet protocol\"\ndrivers/usb/gadget/Kconfig:337:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:338:\tdepends on NET\ndrivers/usb/gadget/Kconfig:339:\tdepends on PHONET\ndrivers/usb/gadget/Kconfig-340-\tselect USB_U_ETHER\n--\ndrivers/usb/gadget/Kconfig=345=config USB_CONFIGFS_MASS_STORAGE\ndrivers/usb/gadget/Kconfig-346-\tbool \"Mass storage\"\ndrivers/usb/gadget/Kconfig:347:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:348:\tdepends on BLOCK\ndrivers/usb/gadget/Kconfig-349-\tselect USB_F_MASS_STORAGE\n--\ndrivers/usb/gadget/Kconfig=356=config USB_CONFIGFS_F_LB_SS\ndrivers/usb/gadget/Kconfig-357-\tbool \"Loopback and sourcesink function (for testing)\"\ndrivers/usb/gadget/Kconfig:358:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig-359-\tselect USB_F_SS_LB\n--\ndrivers/usb/gadget/Kconfig=369=config USB_CONFIGFS_F_FS\ndrivers/usb/gadget/Kconfig-370-\tbool \"Function filesystem (FunctionFS)\"\ndrivers/usb/gadget/Kconfig:371:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig-372-\tselect USB_F_FS\n--\ndrivers/usb/gadget/Kconfig=381=config USB_CONFIGFS_F_UAC1\ndrivers/usb/gadget/Kconfig-382-\tbool \"Audio Class 1.0\"\ndrivers/usb/gadget/Kconfig:383:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:384:\tdepends on SND\ndrivers/usb/gadget/Kconfig-385-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/Kconfig=399=config USB_CONFIGFS_F_UAC1_LEGACY\ndrivers/usb/gadget/Kconfig-400-\tbool \"Audio Class 1.0 (legacy implementation)\"\ndrivers/usb/gadget/Kconfig:401:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:402:\tdepends on SND\ndrivers/usb/gadget/Kconfig-403-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/Kconfig=412=config USB_CONFIGFS_F_UAC2\ndrivers/usb/gadget/Kconfig-413-\tbool \"Audio Class 2.0\"\ndrivers/usb/gadget/Kconfig:414:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:415:\tdepends on SND\ndrivers/usb/gadget/Kconfig-416-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/Kconfig=431=config USB_CONFIGFS_F_MIDI\ndrivers/usb/gadget/Kconfig-432-\tbool \"MIDI function\"\ndrivers/usb/gadget/Kconfig:433:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:434:\tdepends on SND\ndrivers/usb/gadget/Kconfig-435-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/Kconfig=445=config USB_CONFIGFS_F_MIDI2\ndrivers/usb/gadget/Kconfig-446-\tbool \"MIDI 2.0 function\"\ndrivers/usb/gadget/Kconfig:447:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:448:\tdepends on SND\ndrivers/usb/gadget/Kconfig-449-\tselect USB_LIBCOMPOSITE\n--\ndrivers/usb/gadget/Kconfig=458=config USB_CONFIGFS_F_HID\ndrivers/usb/gadget/Kconfig-459-\tbool \"HID function\"\ndrivers/usb/gadget/Kconfig:460:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig-461-\tselect USB_F_HID\n--\ndrivers/usb/gadget/Kconfig=468=config USB_CONFIGFS_F_UVC\ndrivers/usb/gadget/Kconfig-469-\tbool \"USB Webcam function\"\ndrivers/usb/gadget/Kconfig:470:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig:471:\tdepends on VIDEO_DEV\ndrivers/usb/gadget/Kconfig:472:\tdepends on VIDEO_DEV\ndrivers/usb/gadget/Kconfig-473-\tselect VIDEOBUF2_DMA_SG\n--\ndrivers/usb/gadget/Kconfig=481=config USB_CONFIGFS_F_PRINTER\n--\ndrivers/usb/gadget/Kconfig-483-\tselect USB_F_PRINTER\ndrivers/usb/gadget/Kconfig:484:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig-485-\thelp\n--\ndrivers/usb/gadget/Kconfig=495=config USB_CONFIGFS_F_TCM\ndrivers/usb/gadget/Kconfig-496-\tbool \"USB Gadget Target Fabric\"\ndrivers/usb/gadget/Kconfig:497:\tdepends on TARGET_CORE\ndrivers/usb/gadget/Kconfig:498:\tdepends on USB_CONFIGFS\ndrivers/usb/gadget/Kconfig-499-\tselect USB_LIBCOMPOSITE\n"
}

gemini-3.1-pro-preview

null

null

							input: 14036
							output: 35
							thoughts: 24
						

Okay, here's my take on those thoughts, tailored for an expert audience:

**Diving into USB Gadget Drivers**

Right, so we're talking about `USB_GADGET`, the core module for USB device emulation. My first thought is always to pinpoint its dependencies. It's almost axiomatic in this area. `USB_GADGET` *has* to rely on something fundamental within the USB subsystem itself. We need to figure out what those are to really understand the implications of tweaking this. What's upstream of it? Power management? The core USB controller driver model? The specific hardware platform? Getting at those relationships is key to knowing where performance bottlenecks or compatibility issues might crop up. This is the starting point for any in-depth exploration or modification of a gadget driver. It's never just a standalone module.

{
  "Expression": "menuconfig USB_GADGET",
  "PathPrefix": "drivers/usb/gadget/Kconfig"
}

{
  "Output": "drivers/usb/gadget/Kconfig-16-\ndrivers/usb/gadget/Kconfig:17:menuconfig USB_GADGET\ndrivers/usb/gadget/Kconfig-18-\ttristate \"USB Gadget Support\"\n"
}

gemini-3.1-pro-preview

null

null

							input: 14339
							output: 35
							thoughts: 22
						

Okay, let's dive into this Kconfig file for USB gadget drivers.

**Deep Dive into USB Gadget Driver Configuration**

Alright, I'm starting by taking a look at the first 20 lines of the `drivers/usb/gadget/Kconfig` file. Given my expertise, I'm expecting this to lay out the fundamental options for configuring USB gadget functionality within the kernel. I anticipate seeing the main feature switches, possibly the top-level selection for whether any gadget support is built at all. I'll be looking for any default values assigned, and if there's any hint of organization, maybe sections for specific gadget types. I'll be noting any cross-dependencies on other kernel subsystems—e.g., if there's an immediate dependency on USB core or something else. I'm keeping an eye out for any comments, especially if they explain the purpose of a particular option in relation to the functionality it enables. The ultimate goal here is to get a handle on the overall structure and design of the gadget driver configuration so I can understand how best to approach its customization or potential extensions.

{
  "File": "drivers/usb/gadget/Kconfig",
  "FirstLine": 1,
  "LineCount": 20
}

{
  "Contents": "   1:\t# SPDX-License-Identifier: GPL-2.0\n   2:\t#\n   3:\t# USB Gadget support on a system involves\n   4:\t#    (a) a peripheral controller, and\n   5:\t#    (b) the gadget driver using it.\n   6:\t#\n   7:\t# NOTE:  Gadget support ** DOES NOT ** depend on host-side CONFIG_USB !!\n   8:\t#\n   9:\t#  - Host systems (like PCs) need CONFIG_USB (with \"A\" jacks).\n  10:\t#  - Peripherals (like PDAs) need CONFIG_USB_GADGET (with \"B\" jacks).\n  11:\t#  - Some systems have both kinds of controllers.\n  12:\t#\n  13:\t# With help from a special transceiver and a \"Mini-AB\" jack, systems with\n  14:\t# both kinds of controller can also support \"USB On-the-Go\" (CONFIG_USB_OTG).\n  15:\t#\n  16:\t\n  17:\tmenuconfig USB_GADGET\n  18:\t\ttristate \"USB Gadget Support\"\n  19:\t\tselect USB_COMMON\n  20:\t\tselect NLS\n"
}

gemini-3.1-pro-preview

null

null

							input: 14938
							output: 38
							thoughts: 518
						

**Analyzing the USB Raw Gadget Driver Patch**

Okay, so I'm looking at this `USB_GADGET` configuration, and it doesn't have any explicit dependencies, just selects `USB_COMMON` and `NLS`. Seems straightforward enough. The configs we are interested in are `USB_RAW_GADGET` and `USB_GADGET`, as well as `USB_DUMMY_HCD`, which syzkaller uses for USB controller emulation. However, for the `USB_RAW_GADGET` functionality, the config itself is sufficient.

Let's dive into the code. The patch touches several key functions in `drivers/usb/gadget/legacy/raw_gadget.c`: `dev_free`, `gadget_bind`, `gadget_unbind`, `raw_ioctl_event_fetch`, `raw_process_ep0_io`, `raw_ioctl_ep_disable`, and `raw_process_ep_io`. These are all integral parts of the USB Raw Gadget driver implementation.

From the description, this patch is addressing a race condition. It sounds like the UDC (USB Device Controller) unbind could happen concurrently with an EP0 or EP IO operation, potentially leading to use-after-free or other memory corruption issues. The fix involves adding a `udc_usage` counter and an `unbind_completion` mechanism. Smart!

Is this patch fuzz-worthy? Absolutely! This is a functional change within a core driver, and, importantly, syzkaller utilizes this driver. Now, syzkaller leverages this driver to fuzz *other* USB drivers. However, this specific patch fixes a bug within `raw_gadget.c` itself. Syzkaller also directly fuzzez this driver, with descriptions for `/dev/raw-gadget`. So, it's definitely worth the effort.

Let's pinpoint those focus symbols for fuzzing. The modified functions are: `gadget_bind`, `gadget_unbind`, `raw_ioctl_event_fetch`, `raw_process_ep0_io`, `raw_ioctl_ep_disable`, and `raw_process_ep_io`.

Now, wait a minute... `gadget_bind` and `gadget_unbind` are *static* functions, acting as callbacks in `struct usb_gadget_driver`. The other four, `raw_ioctl_event_fetch`, `raw_process_ep0_io`, `raw_ioctl_ep_disable`, and `raw_process_ep_io`, are static functions called from `raw_ioctl`. So, let's turn our attention to `raw_ioctl` next.

{
  "Expression": "raw_ioctl",
  "PathPrefix": "drivers/usb/gadget/legacy/raw_gadget.c"
}

{
  "Output": "drivers/usb/gadget/legacy/raw_gadget.c=478=static int raw_release(struct inode *inode, struct file *fd)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-501-\t\t\t\tret);\ndrivers/usb/gadget/legacy/raw_gadget.c:502:\t\t/* Matches kref_get() in raw_ioctl_run(). */\ndrivers/usb/gadget/legacy/raw_gadget.c-503-\t\tkref_put(\u0026dev-\u003ecount, dev_free);\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-513-\ndrivers/usb/gadget/legacy/raw_gadget.c:514:static int raw_ioctl_init(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-515-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-612-\ndrivers/usb/gadget/legacy/raw_gadget.c:613:static int raw_ioctl_run(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-614-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-648-\ndrivers/usb/gadget/legacy/raw_gadget.c:649:static int raw_ioctl_event_fetch(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-650-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c=717=static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io,\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-809-\ndrivers/usb/gadget/legacy/raw_gadget.c:810:static int raw_ioctl_ep0_write(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-811-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-823-\ndrivers/usb/gadget/legacy/raw_gadget.c:824:static int raw_ioctl_ep0_read(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-825-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-847-\ndrivers/usb/gadget/legacy/raw_gadget.c:848:static int raw_ioctl_ep0_stall(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-849-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-891-\ndrivers/usb/gadget/legacy/raw_gadget.c:892:static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-893-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-971-\ndrivers/usb/gadget/legacy/raw_gadget.c:972:static int raw_ioctl_ep_disable(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-973-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1029-\ndrivers/usb/gadget/legacy/raw_gadget.c:1030:static int raw_ioctl_ep_set_clear_halt_wedge(struct raw_dev *dev,\ndrivers/usb/gadget/legacy/raw_gadget.c-1031-\t\tunsigned long value, bool set, bool halt)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c=1114=static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io,\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1217-\ndrivers/usb/gadget/legacy/raw_gadget.c:1218:static int raw_ioctl_ep_write(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1219-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1231-\ndrivers/usb/gadget/legacy/raw_gadget.c:1232:static int raw_ioctl_ep_read(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1233-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1255-\ndrivers/usb/gadget/legacy/raw_gadget.c:1256:static int raw_ioctl_configure(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1257-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1280-\ndrivers/usb/gadget/legacy/raw_gadget.c:1281:static int raw_ioctl_vbus_draw(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1282-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c=1315=static void fill_ep_limits(struct usb_ep *ep, struct usb_raw_ep_limits *limits)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1320-\ndrivers/usb/gadget/legacy/raw_gadget.c:1321:static int raw_ioctl_eps_info(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1322-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1367-\ndrivers/usb/gadget/legacy/raw_gadget.c:1368:static long raw_ioctl(struct file *fd, unsigned int cmd, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1369-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1377-\tcase USB_RAW_IOCTL_INIT:\ndrivers/usb/gadget/legacy/raw_gadget.c:1378:\t\tret = raw_ioctl_init(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1379-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1380-\tcase USB_RAW_IOCTL_RUN:\ndrivers/usb/gadget/legacy/raw_gadget.c:1381:\t\tret = raw_ioctl_run(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1382-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1383-\tcase USB_RAW_IOCTL_EVENT_FETCH:\ndrivers/usb/gadget/legacy/raw_gadget.c:1384:\t\tret = raw_ioctl_event_fetch(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1385-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1386-\tcase USB_RAW_IOCTL_EP0_WRITE:\ndrivers/usb/gadget/legacy/raw_gadget.c:1387:\t\tret = raw_ioctl_ep0_write(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1388-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1389-\tcase USB_RAW_IOCTL_EP0_READ:\ndrivers/usb/gadget/legacy/raw_gadget.c:1390:\t\tret = raw_ioctl_ep0_read(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1391-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1392-\tcase USB_RAW_IOCTL_EP_ENABLE:\ndrivers/usb/gadget/legacy/raw_gadget.c:1393:\t\tret = raw_ioctl_ep_enable(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1394-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1395-\tcase USB_RAW_IOCTL_EP_DISABLE:\ndrivers/usb/gadget/legacy/raw_gadget.c:1396:\t\tret = raw_ioctl_ep_disable(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1397-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1398-\tcase USB_RAW_IOCTL_EP_WRITE:\ndrivers/usb/gadget/legacy/raw_gadget.c:1399:\t\tret = raw_ioctl_ep_write(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1400-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1401-\tcase USB_RAW_IOCTL_EP_READ:\ndrivers/usb/gadget/legacy/raw_gadget.c:1402:\t\tret = raw_ioctl_ep_read(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1403-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1404-\tcase USB_RAW_IOCTL_CONFIGURE:\ndrivers/usb/gadget/legacy/raw_gadget.c:1405:\t\tret = raw_ioctl_configure(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1406-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1407-\tcase USB_RAW_IOCTL_VBUS_DRAW:\ndrivers/usb/gadget/legacy/raw_gadget.c:1408:\t\tret = raw_ioctl_vbus_draw(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1409-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1410-\tcase USB_RAW_IOCTL_EPS_INFO:\ndrivers/usb/gadget/legacy/raw_gadget.c:1411:\t\tret = raw_ioctl_eps_info(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1412-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1413-\tcase USB_RAW_IOCTL_EP0_STALL:\ndrivers/usb/gadget/legacy/raw_gadget.c:1414:\t\tret = raw_ioctl_ep0_stall(dev, value);\ndrivers/usb/gadget/legacy/raw_gadget.c-1415-\t\tbreak;\ndrivers/usb/gadget/legacy/raw_gadget.c-1416-\tcase USB_RAW_IOCTL_EP_SET_HALT:\ndrivers/usb/gadget/legacy/raw_gadget.c:1417:\t\tret = raw_ioctl_ep_set_clear_halt_wedge(\ndrivers/usb/gadget/legacy/raw_gadget.c-1418-\t\t\t\t\tdev, value, true, true);\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1420-\tcase USB_RAW_IOCTL_EP_CLEAR_HALT:\ndrivers/usb/gadget/legacy/raw_gadget.c:1421:\t\tret = raw_ioctl_ep_set_clear_halt_wedge(\ndrivers/usb/gadget/legacy/raw_gadget.c-1422-\t\t\t\t\tdev, value, false, true);\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1424-\tcase USB_RAW_IOCTL_EP_SET_WEDGE:\ndrivers/usb/gadget/legacy/raw_gadget.c:1425:\t\tret = raw_ioctl_ep_set_clear_halt_wedge(\ndrivers/usb/gadget/legacy/raw_gadget.c-1426-\t\t\t\t\tdev, value, true, false);\n--\ndrivers/usb/gadget/legacy/raw_gadget.c=1437=static const struct file_operations raw_fops = {\ndrivers/usb/gadget/legacy/raw_gadget.c-1438-\t.open =\t\t\traw_open,\ndrivers/usb/gadget/legacy/raw_gadget.c:1439:\t.unlocked_ioctl =\traw_ioctl,\ndrivers/usb/gadget/legacy/raw_gadget.c:1440:\t.compat_ioctl =\t\traw_ioctl,\ndrivers/usb/gadget/legacy/raw_gadget.c-1441-\t.release =\t\traw_release,\n"
}

gemini-3.1-pro-preview

null

null

							input: 19436
							output: 37
							thoughts: 211
						

**Analyzing the USB Gadget ioctl Structure**

Okay, so I'm diving into this `raw_ioctl` function, and it's looking like the central user-space entry point for the gadget driver. I see that it's calling a few static functions internally: `raw_ioctl_event_fetch`, `raw_process_ep0_io`, `raw_ioctl_ep_disable`, and `raw_process_ep_io`. Interesting. It looks like `raw_process_ep0_io` handles endpoint 0 I/O operations and that it is also called by `raw_ioctl_ep0_write` and `raw_ioctl_ep0_read`. Similarly, `raw_process_ep_io` is the workhorse for other endpoints, accessed via `raw_ioctl_ep_write` and `raw_ioctl_ep_read`.

So, the key functions to really understand are `raw_ioctl` itself, and then these endpoint processing functions. I'd assumed `raw_ioctl` would be non-static, but it looks like it's *also* static. I need to make sure I am not missing any non-static entry points, so let's start checking `raw_gadget.c` for any non-static functions.

{
  "Expression": "^static",
  "PathPrefix": "drivers/usb/gadget/legacy/raw_gadget.c"
}

{
  "Output": "drivers/usb/gadget/legacy/raw_gadget.c=37=MODULE_LICENSE(\"GPL\");\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-40-\ndrivers/usb/gadget/legacy/raw_gadget.c:41:static DEFINE_IDA(driver_id_numbers);\ndrivers/usb/gadget/legacy/raw_gadget.c-42-#define DRIVER_DRIVER_NAME_LENGTH_MAX\t32\n--\ndrivers/usb/gadget/legacy/raw_gadget.c=47=struct raw_event_queue {\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-54-\ndrivers/usb/gadget/legacy/raw_gadget.c:55:static void raw_event_queue_init(struct raw_event_queue *queue)\ndrivers/usb/gadget/legacy/raw_gadget.c-56-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-61-\ndrivers/usb/gadget/legacy/raw_gadget.c:62:static int raw_event_queue_add(struct raw_event_queue *queue,\ndrivers/usb/gadget/legacy/raw_gadget.c-63-\tenum usb_raw_event_type type, size_t length, const void *data)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-88-\ndrivers/usb/gadget/legacy/raw_gadget.c:89:static struct usb_raw_event *raw_event_queue_fetch(\ndrivers/usb/gadget/legacy/raw_gadget.c-90-\t\t\t\tstruct raw_event_queue *queue)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-120-\ndrivers/usb/gadget/legacy/raw_gadget.c:121:static void raw_event_queue_destroy(struct raw_event_queue *queue)\ndrivers/usb/gadget/legacy/raw_gadget.c-122-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c=160=struct raw_dev {\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-190-\ndrivers/usb/gadget/legacy/raw_gadget.c:191:static struct raw_dev *dev_new(void)\ndrivers/usb/gadget/legacy/raw_gadget.c-192-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-206-\ndrivers/usb/gadget/legacy/raw_gadget.c:207:static void dev_free(struct kref *kref)\ndrivers/usb/gadget/legacy/raw_gadget.c-208-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-221-\ndrivers/usb/gadget/legacy/raw_gadget.c:222:static int raw_queue_event(struct raw_dev *dev,\ndrivers/usb/gadget/legacy/raw_gadget.c-223-\tenum usb_raw_event_type type, size_t length, const void *data)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-236-\ndrivers/usb/gadget/legacy/raw_gadget.c:237:static void gadget_ep0_complete(struct usb_ep *ep, struct usb_request *req)\ndrivers/usb/gadget/legacy/raw_gadget.c-238-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-255-\ndrivers/usb/gadget/legacy/raw_gadget.c:256:static u8 get_ep_addr(const char *name)\ndrivers/usb/gadget/legacy/raw_gadget.c-257-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-268-\ndrivers/usb/gadget/legacy/raw_gadget.c:269:static int gadget_bind(struct usb_gadget *gadget,\ndrivers/usb/gadget/legacy/raw_gadget.c-270-\t\t\tstruct usb_gadget_driver *driver)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-320-\ndrivers/usb/gadget/legacy/raw_gadget.c:321:static void gadget_unbind(struct usb_gadget *gadget)\ndrivers/usb/gadget/legacy/raw_gadget.c-322-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-370-\ndrivers/usb/gadget/legacy/raw_gadget.c:371:static int gadget_setup(struct usb_gadget *gadget,\ndrivers/usb/gadget/legacy/raw_gadget.c-372-\t\t\tconst struct usb_ctrlrequest *ctrl)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-415-\ndrivers/usb/gadget/legacy/raw_gadget.c:416:static void gadget_disconnect(struct usb_gadget *gadget)\ndrivers/usb/gadget/legacy/raw_gadget.c-417-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-425-}\ndrivers/usb/gadget/legacy/raw_gadget.c:426:static void gadget_suspend(struct usb_gadget *gadget)\ndrivers/usb/gadget/legacy/raw_gadget.c-427-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-435-}\ndrivers/usb/gadget/legacy/raw_gadget.c:436:static void gadget_resume(struct usb_gadget *gadget)\ndrivers/usb/gadget/legacy/raw_gadget.c-437-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-445-}\ndrivers/usb/gadget/legacy/raw_gadget.c:446:static void gadget_reset(struct usb_gadget *gadget)\ndrivers/usb/gadget/legacy/raw_gadget.c-447-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-458-\ndrivers/usb/gadget/legacy/raw_gadget.c:459:static struct miscdevice raw_misc_device;\ndrivers/usb/gadget/legacy/raw_gadget.c-460-\ndrivers/usb/gadget/legacy/raw_gadget.c:461:static int raw_open(struct inode *inode, struct file *fd)\ndrivers/usb/gadget/legacy/raw_gadget.c-462-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-477-\ndrivers/usb/gadget/legacy/raw_gadget.c:478:static int raw_release(struct inode *inode, struct file *fd)\ndrivers/usb/gadget/legacy/raw_gadget.c-479-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-513-\ndrivers/usb/gadget/legacy/raw_gadget.c:514:static int raw_ioctl_init(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-515-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-612-\ndrivers/usb/gadget/legacy/raw_gadget.c:613:static int raw_ioctl_run(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-614-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-648-\ndrivers/usb/gadget/legacy/raw_gadget.c:649:static int raw_ioctl_event_fetch(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-650-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-693-\ndrivers/usb/gadget/legacy/raw_gadget.c:694:static void *raw_alloc_io_data(struct usb_raw_ep_io *io, void __user *ptr,\ndrivers/usb/gadget/legacy/raw_gadget.c-695-\t\t\t\tbool get_from_user)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-716-\ndrivers/usb/gadget/legacy/raw_gadget.c:717:static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io,\ndrivers/usb/gadget/legacy/raw_gadget.c-718-\t\t\t\tvoid *data, bool in)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-809-\ndrivers/usb/gadget/legacy/raw_gadget.c:810:static int raw_ioctl_ep0_write(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-811-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-823-\ndrivers/usb/gadget/legacy/raw_gadget.c:824:static int raw_ioctl_ep0_read(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-825-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-847-\ndrivers/usb/gadget/legacy/raw_gadget.c:848:static int raw_ioctl_ep0_stall(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-849-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-891-\ndrivers/usb/gadget/legacy/raw_gadget.c:892:static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-893-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-971-\ndrivers/usb/gadget/legacy/raw_gadget.c:972:static int raw_ioctl_ep_disable(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-973-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1029-\ndrivers/usb/gadget/legacy/raw_gadget.c:1030:static int raw_ioctl_ep_set_clear_halt_wedge(struct raw_dev *dev,\ndrivers/usb/gadget/legacy/raw_gadget.c-1031-\t\tunsigned long value, bool set, bool halt)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1097-\ndrivers/usb/gadget/legacy/raw_gadget.c:1098:static void gadget_ep_complete(struct usb_ep *ep, struct usb_request *req)\ndrivers/usb/gadget/legacy/raw_gadget.c-1099-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1113-\ndrivers/usb/gadget/legacy/raw_gadget.c:1114:static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io,\ndrivers/usb/gadget/legacy/raw_gadget.c-1115-\t\t\t\tvoid *data, bool in)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1217-\ndrivers/usb/gadget/legacy/raw_gadget.c:1218:static int raw_ioctl_ep_write(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1219-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1231-\ndrivers/usb/gadget/legacy/raw_gadget.c:1232:static int raw_ioctl_ep_read(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1233-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1255-\ndrivers/usb/gadget/legacy/raw_gadget.c:1256:static int raw_ioctl_configure(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1257-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1280-\ndrivers/usb/gadget/legacy/raw_gadget.c:1281:static int raw_ioctl_vbus_draw(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1282-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1303-\ndrivers/usb/gadget/legacy/raw_gadget.c:1304:static void fill_ep_caps(struct usb_ep_caps *caps,\ndrivers/usb/gadget/legacy/raw_gadget.c-1305-\t\t\t\tstruct usb_raw_ep_caps *raw_caps)\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1314-\ndrivers/usb/gadget/legacy/raw_gadget.c:1315:static void fill_ep_limits(struct usb_ep *ep, struct usb_raw_ep_limits *limits)\ndrivers/usb/gadget/legacy/raw_gadget.c-1316-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1320-\ndrivers/usb/gadget/legacy/raw_gadget.c:1321:static int raw_ioctl_eps_info(struct raw_dev *dev, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1322-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1367-\ndrivers/usb/gadget/legacy/raw_gadget.c:1368:static long raw_ioctl(struct file *fd, unsigned int cmd, unsigned long value)\ndrivers/usb/gadget/legacy/raw_gadget.c-1369-{\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1436-\ndrivers/usb/gadget/legacy/raw_gadget.c:1437:static const struct file_operations raw_fops = {\ndrivers/usb/gadget/legacy/raw_gadget.c-1438-\t.open =\t\t\traw_open,\n--\ndrivers/usb/gadget/legacy/raw_gadget.c-1443-\ndrivers/usb/gadget/legacy/raw_gadget.c:1444:static struct miscdevice raw_misc_device = {\ndrivers/usb/gadget/legacy/raw_gadget.c-1445-\t.minor = MISC_DYNAMIC_MINOR,\n"
}

gemini-3.1-pro-preview

null

null

							input: 23807
							output: 34
							thoughts: 461
						

**Focus Symbol Selection: A Deep Dive into `raw_gadget.c`**

Okay, let's break this down. I'm looking at how to identify the correct symbols for the `FocusSymbols` configuration, and the `raw_gadget.c` file is presenting some interesting nuances. Initially, I thought that I should choose the non-static functions over static ones. However, I've noticed a crucial detail: functions like `raw_ioctl`, `gadget_bind`, and `gadget_unbind` are *static* but their addresses are taken because they are assigned to function pointers in the `raw_fops` and `struct usb_gadget_driver` structures respectively. Therefore, they won't be inlined, and their distinct symbol addresses are perfectly usable as entry points.

The prompt explicitly says to favor non-static, non-inlined API entrypoint functions. Since `raw_ioctl`, `gadget_bind`, and `gadget_unbind` are static functions but *not* inlined, they seem like prime candidates.

Now, `raw_ioctl` looks like a significant multiplexer. The actual logic modifications are buried within its sub-functions: `raw_process_ep0_io`, `raw_ioctl_ep_disable`, and `raw_process_ep_io`. My gut feeling is that those might be inlined due to their usage, but they're not trivial. However, since the goal is to identify distinct entry points, I'll stick with `raw_ioctl`, `gadget_bind`, and `gadget_unbind` for the focus. I'm reasonably confident that these are the key symbols to track.

Finally, I need to check the dependencies. I have to double-check that `USB_RAW_GADGET` is the only config I need. I know `USB_GADGET` is fundamental. I think I will need `USB_DUMMY_HCD` if I'm testing without real hardware, but since this patch is within `raw_gadget.c`, `USB_RAW_GADGET` is the core one that enables this particular file's compilation. Checking the legacy `Makefile` is a good idea to confirm.

{
  "Expression": "raw_gadget",
  "PathPrefix": "drivers/usb/gadget/legacy/Makefile"
}

{
  "Output": "drivers/usb/gadget/legacy/Makefile=45=obj-$(CONFIG_USB_GADGET_TARGET)\t+= tcm_usb_gadget.o\ndrivers/usb/gadget/legacy/Makefile:46:obj-$(CONFIG_USB_RAW_GADGET)\t+= raw_gadget.o\n"
}

gemini-3.1-pro-preview

null

null

							input: 24859
							output: 29
							thoughts: 68
						

**USB Gadget Configuration Conundrum**

Okay, so I'm focusing on the USB raw gadget driver, and it seems like setting `CONFIG_USB_RAW_GADGET` should be all I need to get `raw_gadget.c` compiled. That makes sense, pretty straightforward. But hold on... something feels off. I vaguely recall needing a more encompassing configuration option to even get into the relevant Makefiles. Let me double-check the include structure. Right, I think `USB_GADGET` has something to do with that, let me confirm. Let's go look at `drivers/usb/gadget/Makefile` and see what that includes. Hopefully, this clears things up!

{
  "Expression": "legacy",
  "PathPrefix": "drivers/usb/gadget/Makefile"
}

{
  "Output": "drivers/usb/gadget/Makefile=10=libcomposite-y\t\t\t+= composite.o functions.o configfs.o u_f.o\ndrivers/usb/gadget/Makefile-11-\ndrivers/usb/gadget/Makefile:12:obj-$(CONFIG_USB_GADGET)\t+= udc/ function/ legacy/\n"
}

gemini-3.1-pro-preview

null

null

							input: 25196
							output: 36
							thoughts: 750
						

**My Analysis of the USB Raw Gadget Driver Patch**

Okay, so I'm looking at this patch for the USB Raw Gadget driver. First things first: I need `CONFIG_USB_GADGET` to even get into the `legacy/` directory, and it seems like I also need `USB_RAW_GADGET` as well, so my `EnableConfigs` should be `["USB_GADGET", "USB_RAW_GADGET"]`. That sounds right.

Now, let's nail down the focus symbols for the fuzzer. The patch touches `dev_free`, `gadget_bind`, `gadget_unbind`, `raw_ioctl_event_fetch`, `raw_process_ep0_io`, `raw_ioctl_ep_disable`, and `raw_process_ep_io`. Let's think through which of these are likely to be inlined by the compiler. `gadget_bind` and `gadget_unbind` are function pointers, so definitely not inlined. `dev_free` gets passed to `kref_put`, so also not inlined. The others, `raw_ioctl_event_fetch`, `raw_process_ep0_io`, `raw_ioctl_ep_disable`, and `raw_process_ep_io`, are called from `raw_ioctl` via a switch statement. They *could* be inlined, but they look pretty substantial.

Given all that, I think I'll include `gadget_bind`, `gadget_unbind`, and `raw_ioctl` as the main entry points. I might also include `raw_process_ep0_io` and `raw_process_ep_io` because they seem to contain the core logic changes. Wait, I think `raw_ioctl` is the entry point for all of the ioctls, so the fuzzer will be focused on that, so I will stick with just `gadget_bind`, `gadget_unbind`, and `raw_ioctl`.

Let's double-check any dependencies. `USB_GADGET` itself doesn't depend on anything, but it selects `USB_COMMON` and `NLS`. However, `USB_GADGET` and `USB_RAW_GADGET` should be sufficient. Okay, just to be thorough, I'll confirm that only `drivers/usb/gadget/legacy/raw_gadget.c` is being modified. Yep, just the one file.

Now, time to summarize this clearly for the fuzzer. This patch addresses a race condition in the USB Raw Gadget driver. It deals with UDC unbind and endpoint IO operations. Specifically, it introduces a `udc_usage` counter and an `unbind_completion` to ensure that `gadget_unbind` waits for any pending IO to finish before completing the unbind process. This is a functional change in a key driver used for USB emulation and fuzzing. The patch is reachable in virtualized environments.

So, here's the information I'm feeding the fuzzer:

*   `WorthFuzzing: true`
*   `FocusSymbols: gadget_bind, gadget_unbind, raw_ioctl`
*   `EnableConfigs: USB_GADGET, USB_RAW_GADGET`

Alright, let me double-check about `USB_DUMMY_HCD`. Ah, that's the dummy host controller and device controller. It is used to connect the raw gadget to a dummy host. While `USB_RAW_GADGET` compiles the code, to actually *test* it, syzkaller needs a UDC (USB Device Controller). `USB_DUMMY_HCD` provides this UDC in a virtualized environment. Let me double-check that this is a config. Good. I think I'm good to go.

{
  "Expression": "config USB_DUMMY_HCD",
  "PathPrefix": "drivers/usb/gadget/"
}

{
  "Output": "drivers/usb/gadget/udc/Kconfig=422=source \"drivers/usb/gadget/udc/cdns2/Kconfig\"\n--\ndrivers/usb/gadget/udc/Kconfig-427-\ndrivers/usb/gadget/udc/Kconfig:428:config USB_DUMMY_HCD\ndrivers/usb/gadget/udc/Kconfig-429-\ttristate \"Dummy HCD (DEVELOPMENT)\"\n"
}

gemini-3.1-pro-preview

null

null

							input: 26931
							output: 34
							thoughts: 96
						

**Checking the USB Dummy Host Controller Configuration**

Okay, so I see that `USB_DUMMY_HCD` is indeed defined within the `drivers/usb/gadget/udc/Kconfig` file. That confirms what I was thinking. If I enable this, it guarantees that the dummy USB device controller is available. And I know I need that to reliably trigger the `gadget_bind` and `gadget_unbind` functions within a virtual machine environment where I *don't* have access to actual, physical USB hardware. It's a key requirement for the testing I'm doing. Now, just to be thorough and to double-check my assumptions, I should quickly review the dependencies of `USB_DUMMY_HCD` to be absolutely certain there are no unforeseen conflicts or prerequisites. Let's see...

{
  "Expression": "depends on",
  "PathPrefix": "drivers/usb/gadget/udc/Kconfig"
}

{
  "Output": "drivers/usb/gadget/udc/Kconfig=33=config USB_AT91\ndrivers/usb/gadget/udc/Kconfig-34-\ttristate \"Atmel AT91 USB Device Port\"\ndrivers/usb/gadget/udc/Kconfig:35:\tdepends on ARCH_AT91\ndrivers/usb/gadget/udc/Kconfig:36:\tdepends on OF\ndrivers/usb/gadget/udc/Kconfig-37-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=46=config USB_LPC32XX\ndrivers/usb/gadget/udc/Kconfig-47-\ttristate \"LPC32XX USB Peripheral Controller\"\ndrivers/usb/gadget/udc/Kconfig:48:\tdepends on ARCH_LPC32XX || COMPILE_TEST\ndrivers/usb/gadget/udc/Kconfig:49:\tdepends on I2C\ndrivers/usb/gadget/udc/Kconfig-50-\tselect USB_ISP1301\n--\ndrivers/usb/gadget/udc/Kconfig=58=config USB_ATMEL_USBA\ndrivers/usb/gadget/udc/Kconfig-59-\ttristate \"Atmel USBA\"\ndrivers/usb/gadget/udc/Kconfig:60:\tdepends on ARCH_AT91\ndrivers/usb/gadget/udc/Kconfig-61-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=80=config USB_BCM63XX_UDC\ndrivers/usb/gadget/udc/Kconfig-81-\ttristate \"Broadcom BCM63xx Peripheral Controller\"\ndrivers/usb/gadget/udc/Kconfig:82:\tdepends on BCM63XX\ndrivers/usb/gadget/udc/Kconfig-83-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=91=config USB_FSL_USB2\ndrivers/usb/gadget/udc/Kconfig-92-\ttristate \"Freescale Highspeed USB DR Peripheral Controller\"\ndrivers/usb/gadget/udc/Kconfig:93:\tdepends on FSL_SOC\ndrivers/usb/gadget/udc/Kconfig-94-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=105=config USB_GR_UDC\ndrivers/usb/gadget/udc/Kconfig-106-\ttristate \"Aeroflex Gaisler GRUSBDC USB Peripheral Controller Driver\"\ndrivers/usb/gadget/udc/Kconfig:107:\tdepends on HAS_DMA\ndrivers/usb/gadget/udc/Kconfig-108-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=112=config USB_OMAP\ndrivers/usb/gadget/udc/Kconfig-113-\ttristate \"OMAP USB Device Controller\"\ndrivers/usb/gadget/udc/Kconfig:114:\tdepends on ARCH_OMAP1\ndrivers/usb/gadget/udc/Kconfig-115-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=126=config USB_PXA25X\ndrivers/usb/gadget/udc/Kconfig-127-\ttristate \"PXA 25x or IXP 4xx\"\ndrivers/usb/gadget/udc/Kconfig:128:\tdepends on (ARCH_PXA \u0026\u0026 PXA25x) || ARCH_IXP4XX\ndrivers/usb/gadget/udc/Kconfig:129:\tdepends on HAS_IOMEM\ndrivers/usb/gadget/udc/Kconfig-130-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=144=config USB_PXA25X_SMALL\ndrivers/usb/gadget/udc/Kconfig:145:\tdepends on USB_PXA25X\ndrivers/usb/gadget/udc/Kconfig-146-\tbool\n--\ndrivers/usb/gadget/udc/Kconfig=152=config USB_R8A66597\ndrivers/usb/gadget/udc/Kconfig-153-\ttristate \"Renesas R8A66597 USB Peripheral Controller\"\ndrivers/usb/gadget/udc/Kconfig:154:\tdepends on HAS_DMA\ndrivers/usb/gadget/udc/Kconfig-155-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=164=config USB_RENESAS_USBHS_UDC\ndrivers/usb/gadget/udc/Kconfig-165-\ttristate 'Renesas USBHS controller'\ndrivers/usb/gadget/udc/Kconfig:166:\tdepends on USB_RENESAS_USBHS\ndrivers/usb/gadget/udc/Kconfig-167-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=176=config USB_RZV2M_USB3DRD\ndrivers/usb/gadget/udc/Kconfig-177-\ttristate 'Renesas USB3.1 DRD controller'\ndrivers/usb/gadget/udc/Kconfig:178:\tdepends on ARCH_R9A09G011 || COMPILE_TEST\ndrivers/usb/gadget/udc/Kconfig-179-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=186=config USB_RENESAS_USB3\ndrivers/usb/gadget/udc/Kconfig-187-\ttristate 'Renesas USB3.0 Peripheral controller'\ndrivers/usb/gadget/udc/Kconfig:188:\tdepends on ARCH_RENESAS || COMPILE_TEST\ndrivers/usb/gadget/udc/Kconfig:189:\tdepends on USB_RZV2M_USB3DRD || !USB_RZV2M_USB3DRD\ndrivers/usb/gadget/udc/Kconfig:190:\tdepends on EXTCON\ndrivers/usb/gadget/udc/Kconfig-191-\tselect USB_ROLE_SWITCH\n--\ndrivers/usb/gadget/udc/Kconfig=200=config USB_RENESAS_USBF\ndrivers/usb/gadget/udc/Kconfig-201-\ttristate 'Renesas USB Function controller'\ndrivers/usb/gadget/udc/Kconfig:202:\tdepends on ARCH_RENESAS || COMPILE_TEST\ndrivers/usb/gadget/udc/Kconfig-203-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=211=config USB_PXA27X\ndrivers/usb/gadget/udc/Kconfig-212-\ttristate \"PXA 27x\"\ndrivers/usb/gadget/udc/Kconfig:213:\tdepends on HAS_IOMEM\ndrivers/usb/gadget/udc/Kconfig-214-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=225=config USB_SNP_CORE\ndrivers/usb/gadget/udc/Kconfig:226:\tdepends on (USB_AMD5536UDC || USB_SNP_UDC_PLAT)\ndrivers/usb/gadget/udc/Kconfig:227:\tdepends on HAS_DMA\ndrivers/usb/gadget/udc/Kconfig-228-\ttristate\n--\ndrivers/usb/gadget/udc/Kconfig=240=config USB_SNP_UDC_PLAT\ndrivers/usb/gadget/udc/Kconfig-241-\ttristate \"Synopsys USB 2.0 Device controller\"\ndrivers/usb/gadget/udc/Kconfig:242:\tdepends on USB_GADGET \u0026\u0026 OF \u0026\u0026 HAS_DMA\ndrivers/usb/gadget/udc/Kconfig:243:\tdepends on EXTCON || EXTCON=n\ndrivers/usb/gadget/udc/Kconfig-244-\tselect USB_SNP_CORE\n--\ndrivers/usb/gadget/udc/Kconfig=258=config USB_M66592\ndrivers/usb/gadget/udc/Kconfig-259-\ttristate \"Renesas M66592 USB Peripheral Controller\"\ndrivers/usb/gadget/udc/Kconfig:260:\tdepends on HAS_IOMEM\ndrivers/usb/gadget/udc/Kconfig-261-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=276=config USB_AMD5536UDC\ndrivers/usb/gadget/udc/Kconfig-277-\ttristate \"AMD5536 UDC\"\ndrivers/usb/gadget/udc/Kconfig:278:\tdepends on USB_PCI \u0026\u0026 HAS_DMA\ndrivers/usb/gadget/udc/Kconfig-279-\tselect USB_SNP_CORE\n--\ndrivers/usb/gadget/udc/Kconfig=294=config USB_FSL_QE\ndrivers/usb/gadget/udc/Kconfig-295-\ttristate \"Freescale QE/CPM USB Device Controller\"\ndrivers/usb/gadget/udc/Kconfig:296:\tdepends on FSL_SOC \u0026\u0026 (QUICC_ENGINE || CPM)\ndrivers/usb/gadget/udc/Kconfig:297:\tdepends on !64BIT || BROKEN\ndrivers/usb/gadget/udc/Kconfig-298-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=308=config USB_NET2280\ndrivers/usb/gadget/udc/Kconfig-309-\ttristate \"NetChip NET228x / PLX USB3x8x\"\ndrivers/usb/gadget/udc/Kconfig:310:\tdepends on USB_PCI\ndrivers/usb/gadget/udc/Kconfig-311-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=333=config USB_GOKU\ndrivers/usb/gadget/udc/Kconfig-334-\ttristate \"Toshiba TC86C001 'Goku-S'\"\ndrivers/usb/gadget/udc/Kconfig:335:\tdepends on USB_PCI\ndrivers/usb/gadget/udc/Kconfig-336-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=347=config USB_EG20T\ndrivers/usb/gadget/udc/Kconfig-348-\ttristate \"Intel QUARK X1000/EG20T PCH/LAPIS Semiconductor IOH(ML7213/ML7831) UDC\"\ndrivers/usb/gadget/udc/Kconfig:349:\tdepends on USB_PCI\ndrivers/usb/gadget/udc/Kconfig-350-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=371=config USB_GADGET_XILINX\ndrivers/usb/gadget/udc/Kconfig-372-\ttristate \"Xilinx USB Driver\"\ndrivers/usb/gadget/udc/Kconfig:373:\tdepends on HAS_DMA\ndrivers/usb/gadget/udc/Kconfig:374:\tdepends on OF\ndrivers/usb/gadget/udc/Kconfig-375-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=386=config USB_MAX3420_UDC\ndrivers/usb/gadget/udc/Kconfig-387-\ttristate \"MAX3420 (USB-over-SPI) support\"\ndrivers/usb/gadget/udc/Kconfig:388:\tdepends on SPI\ndrivers/usb/gadget/udc/Kconfig-389-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=396=config USB_TEGRA_XUDC\ndrivers/usb/gadget/udc/Kconfig-397-\ttristate \"NVIDIA Tegra Superspeed USB 3.0 Device Controller\"\ndrivers/usb/gadget/udc/Kconfig:398:\tdepends on ARCH_TEGRA || COMPILE_TEST\ndrivers/usb/gadget/udc/Kconfig:399:\tdepends on PHY_TEGRA_XUSB\ndrivers/usb/gadget/udc/Kconfig-400-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=407=config USB_ASPEED_UDC\ndrivers/usb/gadget/udc/Kconfig-408-\ttristate \"Aspeed UDC driver support\"\ndrivers/usb/gadget/udc/Kconfig:409:\tdepends on ARCH_ASPEED || COMPILE_TEST\ndrivers/usb/gadget/udc/Kconfig:410:\tdepends on USB_LIBCOMPOSITE\ndrivers/usb/gadget/udc/Kconfig-411-\thelp\n--\ndrivers/usb/gadget/udc/Kconfig=428=config USB_DUMMY_HCD\ndrivers/usb/gadget/udc/Kconfig-429-\ttristate \"Dummy HCD (DEVELOPMENT)\"\ndrivers/usb/gadget/udc/Kconfig:430:\tdepends on USB=y || (USB=m \u0026\u0026 USB_GADGET=m)\ndrivers/usb/gadget/udc/Kconfig-431-\thelp\n"
}

gemini-3.1-pro-preview

null

null

							input: 30608
							output: 190
							thoughts: 498
						

**USB Raw Gadget Fuzzing Configuration**

Okay, let's solidify this fuzzing configuration for the USB Raw Gadget driver. I've been thinking through the dependencies and how to ensure the fuzzer effectively interacts with this driver. Right now, `USB_DUMMY_HCD` is key. My initial thought was to include it because syzkaller uses it for testing `USB_RAW_GADGET`. But I realized, `USB_DUMMY_HCD` is both a UDC *and* an HCD, making it perfect for this test setup.

I need to make sure the fuzzer can actually bind the gadget, so, `USB_DUMMY_HCD` will definitely be in `EnableConfigs`. Given the dependency, `USB_DUMMY_HCD` depends on `USB`, which means that it has to be enabled as well. Also `USB_GADGET` and `USB_RAW_GADGET` need to be enabled for this to work.

Therefore, the list should be `["USB", "USB_GADGET", "USB_RAW_GADGET", "USB_DUMMY_HCD"]`.

I've reviewed the focus symbols for the fuzzing: `gadget_bind`, `gadget_unbind`, `raw_ioctl`, `raw_process_ep0_io`, and `raw_process_ep_io`. These look solid and cover the critical entry points to the driver's functionality, focusing on the core bind/unbind operations, and IO handling.

The reasoning is sound: the patch addresses a race condition between UDC unbind and endpoint IO in the USB Raw Gadget driver, which is a functional change in a core driver used for USB emulation. It's definitely reachable in virtualized environments.

This should be a robust configuration. I'll set the results.

{
  "EnableConfigs": [
    "USB",
    "USB_GADGET",
    "USB_RAW_GADGET",
    "USB_DUMMY_HCD"
  ],
  "FocusSymbols": [
    "gadget_bind",
    "gadget_unbind",
    "raw_ioctl",
    "raw_process_ep0_io",
    "raw_process_ep_io"
  ],
  "Reasoning": "The patch fixes a race condition in the USB Raw Gadget driver between UDC unbind and endpoint IO operations. It introduces a `udc_usage` counter and an `unbind_completion` to ensure that `gadget_unbind` waits for any pending IO to finish before completing the unbind process. This is a functional change in a core driver used for USB emulation and fuzzing, and it is reachable in virtualized environments.",
  "WorthFuzzing": true
}

{
  "EnableConfigs": [
    "USB",
    "USB_GADGET",
    "USB_RAW_GADGET",
    "USB_DUMMY_HCD"
  ],
  "FocusSymbols": [
    "gadget_bind",
    "gadget_unbind",
    "raw_ioctl",
    "raw_process_ep0_io",
    "raw_process_ep_io"
  ],
  "Reasoning": "The patch fixes a race condition in the USB Raw Gadget driver between UDC unbind and endpoint IO operations. It introduces a `udc_usage` counter and an `unbind_completion` to ensure that `gadget_unbind` waits for any pending IO to finish before completing the unbind process. This is a functional change in a core driver used for USB emulation and fuzzing, and it is reachable in virtualized environments.",
  "WorthFuzzing": true
}