| Message ID | 20221215052906.8993-3-quic_ugoswami@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | usb: gadget: f_fs: Prevent race between functionfs_unbind & ffs_ep0_queue_wait | expand |
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index bb6fe1f3a29d..523a961b910b 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -1895,6 +1895,8 @@ static void functionfs_unbind(struct ffs_data *ffs) ENTER(); if (!WARN_ON(!ffs->gadget)) { + /* dequeue before freeing ep0req */ + usb_ep_dequeue(ffs->gadget->ep0, ffs->ep0req); mutex_lock(&ffs->mutex); usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req); ffs->ep0req = NULL;
As per the documentation, function usb_ep_free_request guarantees the request will not be queued or no longer be re-queued (or otherwise used). However, with the current implementation it doesn't make sure that the request in ep0 isn't reused. Fix this by dequeuing the ep0req on functionfs_unbind before freeing the request to align with the definition. Fixes: ddf8abd25994 ("USB: f_fs: the FunctionFS driver") Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com> --- drivers/usb/gadget/function/f_fs.c | 2 ++ 1 file changed, 2 insertions(+)