On Tue, 2023-02-14 at 16:42 -0800, Josh Triplett wrote:
> @@ -4177,17 +4177,37 @@ SYSCALL_DEFINE4(io_uring_register, unsigned
> int, fd, unsigned int, opcode,
> struct io_ring_ctx *ctx;
> long ret = -EBADF;
> struct fd f;
> + bool use_registered_ring;
> +
> + use_registered_ring = !!(opcode &
> IORING_REGISTER_USE_REGISTERED_RING);
> + opcode &= ~IORING_REGISTER_USE_REGISTERED_RING;
>
> if (opcode >= IORING_REGISTER_LAST)
> return -EINVAL;
>
> - f = fdget(fd);
> - if (!f.file)
> - return -EBADF;
> + if (use_registered_ring) {
> + /*
> + * Ring fd has been registered via
> IORING_REGISTER_RING_FDS, we
> + * need only dereference our task private array to
> find it.
> + */
> + struct io_uring_task *tctx = current->io_uring;
>
> - ret = -EOPNOTSUPP;
> - if (!io_is_uring_fops(f.file))
> - goto out_fput;
> + if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX))
> + return -EINVAL;
> + fd = array_index_nospec(fd, IO_RINGFD_REG_MAX);
> + f.file = tctx->registered_rings[fd];
> + f.flags = 0;
> + if (unlikely(!f.file))
> + return -EBADF;
> + opcode &= ~IORING_REGISTER_USE_REGISTERED_RING;
^ this line looks duplicated at the top of the function?
Also - is there a liburing regression test for this?
