In AIO case, the request is freed up if ep_queue fails. However, io_data->req still has the reference to this freed request. In the case of this failure if there is aio_cancel call on this io_data it will lead to an invalid dequeue operation and a potential use after free issue. Fix this by setting the io_data->req to NULL when the request is freed as part of queue failure.

Fixes: 2e4c7553cd6f ("usb: gadget: f_fs: add aio support") Signed-off-by: Sriharsha Allenki sallenki@codeaurora.org CC: stable stable@vger.kernel.org Reviewed-by: Peter Chen peter.chen@nxp.com --- Changes in v2: - As suggested by Greg, updated the tags

drivers/usb/gadget/function/f_fs.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index 571917677d35..767f30b86645 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -1120,6 +1120,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)

ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC); if (unlikely(ret)) { + io_data->req = NULL; usb_ep_free_request(ep->ep, req); goto error_lock; }