Re: [PATCH v2 1/2] mm/memfd: Refactor and cleanup the logic in memfd_create()

[Alice Ryhl <aliceryhl@google.com>]

On Tue, Jan 7, 2025 at 7:48 PM Isaac J. Manjarres
<isaacmanjarres@google.com> wrote:
> +SYSCALL_DEFINE2(memfd_create,
> +               const char __user *, uname,
> +               unsigned int, flags)
> +{
> +       struct file *file;
> +       int fd;
> +       char *name;
> +
> +       name = memfd_create_name(uname);
> +       if (IS_ERR(name))
> +               return PTR_ERR(name);
> +
> +       file = memfd_file_create(name, flags);
> +       /* name is not needed beyond this point. */
>         kfree(name);
> -       return error;
> +       if (IS_ERR(file))
> +               return PTR_ERR(file);
> +
> +       fd = get_unused_fd_flags((flags & MFD_CLOEXEC) ? O_CLOEXEC : 0);
> +       if (fd >= 0)
> +               fd_install(fd, file);
> +       else
> +               fput(file);

You changed the order so that get_unused_fd_flags() happens after
creating the file, so the error path now does fput(file) instead of
put_unused_fd(fd). Is there a reason for this? I would generally
assume that calling get_unused_fd_flags() first is better.

Otherwise this LGTM.


Alice