From: Sriharsha Allenki Date: Thu, 26 Mar 2020 11:56:20 +0000 (+0530) Subject: usb: gadget: f_fs: Fix use after free issue as part of queue failure X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=1cb53343f0eb6cdf0609d4421fad34eeafe731c2;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git usb: gadget: f_fs: Fix use after free issue as part of queue failure commit f63ec55ff904b2f2e126884fcad93175f16ab4bb upstream. 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 CC: stable Reviewed-by: Peter Chen Link: https://lore.kernel.org/r/20200326115620.12571-1-sallenki@codeaurora.org Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index b5747f1270a6..223b28cbf3c8 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -1036,6 +1036,7 @@ 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; }