Re: [PATCH v4] usb: gadget: f_fs: try to fix AIO issue under ARM 64 bit TAGGED mode

On Wed, Feb 26, 2020 at 08:01:52PM +0800, Macpaul Lin wrote:

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index ce1d023..192935f 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -715,7 +715,20 @@ static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req) static ssize_t ffs_copy_to_iter(void *data, int data_len, struct iov_iter *iter) {

• ssize_t ret = copy_to_iter(data, data_len, iter);

• ssize_t ret;

+#if defined(CONFIG_ARM64)

• /*

• * Replace tagged address passed by user space application before
  

• * copying.
  

• */
  

• if (IS_ENABLED(CONFIG_ARM64_TAGGED_ADDR_ABI) &&

• (iter->type == ITER_IOVEC)) {
  

• *(unsigned long *)&iter->iov->iov_base =
  

• 	(unsigned long)untagged_addr(iter->iov->iov_base);
  

• }

+#endif

• ret = copy_to_iter(data, data_len, iter); if (likely(ret == data_len)) return ret;

I had forgotten that we discussed a similar case already a few months ago (thanks to Evgenii for pointing out). Do you have this commit applied to your tree: df325e05a682 ("arm64: Validate tagged addresses in access_ok() called from kernel threads")?