Re: [Bug] io_uring_register_files_update broken

[Pavel Begunkov <asml.silence@gmail.com>]

On 6/30/21 10:14 PM, Victor Stewart wrote:
> i'm fairly confident there is something broken with
> io_uring_register_files_update,
> especially the offset parameter.
> 
> when trying to update a single fd, and getting a successful result of
> 1, proceeding
> operations with IOSQE_FIXED_FILE fail with -9. but if i update all of
> the fds with
> then my recv operations succeed, but close still fails with -9.
> 
> on Clear LInux 5.12.13-1050.native

Thanks for letting know, I'll take a look

 
> here's a diff for liburing send_recv test, to demonstrate this.
> 
> diff --git a/test/send_recv.c b/test/send_recv.c
> index 19adbdd..492b591 100644
> --- a/test/send_recv.c
> +++ b/test/send_recv.c
> @@ -27,6 +27,8 @@ static char str[] = "This is a test of send and recv
> over io_uring!";
>  #      define io_uring_prep_recv io_uring_prep_read
>  #endif
> 
> +static int *fds;
> +
>  static int recv_prep(struct io_uring *ring, struct iovec *iov, int *sock,
>                      int registerfiles)
>  {
> @@ -54,17 +56,28 @@ static int recv_prep(struct io_uring *ring, struct
> iovec *iov, int *sock,
>                 goto err;
>         }
> 
> +       fds = malloc(100 * sizeof(int));
> +       memset(fds, 0xff, sizeof(int) * 100);
> +
>         if (registerfiles) {
> -               ret = io_uring_register_files(ring, &sockfd, 1);
> +               ret = io_uring_register_files(ring, fds, 100);
>                 if (ret) {
>                         fprintf(stderr, "file reg failed\n");
>                         goto err;
>                 }
> -               use_fd = 0;
> -       } else {
> -               use_fd = sockfd;
> +
> +               fds[sockfd] = sockfd;
> +               int result = io_uring_register_files_update(ring,
> sockfd, fds, 1);
> +
> +               if (result != 1)
> +               {
> +                       fprintf(stderr, "file update failed\n");
> +                       goto err;
> +               }
>         }
> 
> +       use_fd = sockfd;
> +
>         sqe = io_uring_get_sqe(ring);
>         io_uring_prep_recv(sqe, use_fd, iov->iov_base, iov->iov_len, 0);
>         if (registerfiles)
> 

-- 
Pavel Begunkov