[PATCH v2 1/2] usb: dwc3: host: fix dangling xhci pointer on init failure

[David Collin <davidcollin899@gmail.com>]

dwc3_host_init()'s error path frees xhci via platform_device_put()
but never clears dwc->xhci, leaving a dangling pointer that
dwc3_host_exit() dereferences unconditionally on removal/shutdown.
Clear dwc->xhci on the error path and return early from
dwc3_host_exit() if NULL.

Fixes: d07e8819a03d ("usb: dwc3: add xHCI Host support")
Cc: stable@vger.kernel.org
Signed-off-by: David Collin <davidcollin899@gmail.com>
---
 drivers/usb/dwc3/host.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
index c5674161b2b0..74117cbb2f42 100644
--- a/drivers/usb/dwc3/host.c
+++ b/drivers/usb/dwc3/host.c
@@ -219,12 +219,16 @@ int dwc3_host_init(struct dwc3 *dwc)
 	return 0;
 err:
 	platform_device_put(xhci);
+	dwc->xhci = NULL;
 	return ret;
 }
 EXPORT_SYMBOL_GPL(dwc3_host_init);
 
 void dwc3_host_exit(struct dwc3 *dwc)
 {
+	if (!dwc->xhci)
+		return;
+
 	if (dwc->sys_wakeup)
 		device_init_wakeup(&dwc->xhci->dev, false);
 
-- 
2.55.0