From 66cae9b5a1d92076b62d47dc102391f8f0493450 Mon Sep 17 00:00:00 2001 From: Chunfeng Yun Date: Fri, 25 May 2018 17:24:57 +0800 Subject: [PATCH] usb: gadget: composite: fix delayed_status race condition when set_interface [ Upstream commit 980900d6318066b9f8314bfb87329a20fd0d1ca4 ] It happens when enable debug log, if set_alt() returns USB_GADGET_DELAYED_STATUS and usb_composite_setup_continue() is called before increasing count of @delayed_status, so fix it by using spinlock of @cdev->lock. Signed-off-by: Chunfeng Yun Tested-by: Jay Hsu Signed-off-by: Felipe Balbi Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/composite.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c index 940de04ed72a..b805962f5154 100644 --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -1720,6 +1720,8 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) */ if (w_value && !f->get_alt) break; + + spin_lock(&cdev->lock); value = f->set_alt(f, w_index, w_value); if (value == USB_GADGET_DELAYED_STATUS) { DBG(cdev, @@ -1729,6 +1731,7 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) DBG(cdev, "delayed_status count %d\n", cdev->delayed_status); } + spin_unlock(&cdev->lock); break; case USB_REQ_GET_INTERFACE: if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE)) -- 2.20.1