Messages in this thread Patch in this message | | | Date | Wed, 3 Sep 2014 14:26:34 +0800 | From | Zhuang Jin Can <> | Subject | [PATCH] usb: dwc3: gadget: Fix desc NULL pointer in dwc3_gadget_ep_queue() |
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dep->endpoint.desc is checked at the beginning of dwc3_gadget_ep_queue(), but after that it may be set to NULL by another thread and then accessed again in dwc3_gadget_ep_queue(). This will lead to kernel oops.
Expand spinlock protection area to aviod race condition.
Signed-off-by: Zhuang Jin Can <jin.can.zhuang@intel.com> Signed-off-by: Jiebing Li <jiebing.li@intel.com> --- drivers/usb/dwc3/gadget.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 349cacc..e8fb231 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1225,16 +1225,17 @@ static int dwc3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request, int ret; + spin_lock_irqsave(&dwc->lock, flags); if (!dep->endpoint.desc) { dev_dbg(dwc->dev, "trying to queue request %p to disabled %s\n", request, ep->name); + spin_unlock_irqrestore(&dwc->lock, flags); return -ESHUTDOWN; } dev_vdbg(dwc->dev, "queing request %p to %s length %d\n", request, ep->name, request->length); - spin_lock_irqsave(&dwc->lock, flags); ret = __dwc3_gadget_ep_queue(dep, req); spin_unlock_irqrestore(&dwc->lock, flags); -- 1.7.9.5
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