On Fri, May 29, 2020 at 07:41:08AM +0000, Luis Chamberlain wrote:
> This moves the binfmt_misc sysctl to its own file to help remove
> clutter from kernel/sysctl.c.
>
> Signed-off-by: Luis Chamberlain <mcg...@kernel.org>
> ---
> fs/binfmt_misc.c | 1 +
> kernel/sysctl.c | 7 -------
> 2 files changed, 1 insertion(+), 7 deletions(-)
>
> diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c
> index f69a043f562b..656b3f5f3bbf 100644
> --- a/fs/binfmt_misc.c
> +++ b/fs/binfmt_misc.c
> @@ -821,6 +821,7 @@ static int __init init_misc_binfmt(void)
> int err = register_filesystem(&bm_fs_type);
> if (!err)
> insert_binfmt(&misc_format);
> + register_sysctl_empty_subdir("fs", "binfmt_misc");
> return err;
Nit: let's make the dir before registering the filesystem. I can't
imagine a realistic situation where userspace is reacting so fast it
would actually fail to mount the fs on /proc/sys/fs/binfmt_misc, but why
risk it?
-Kees
> }
>
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 460532cd5ac8..7714e7b476c2 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -3042,13 +3042,6 @@ static struct ctl_table fs_table[] = {
> .extra1 = SYSCTL_ZERO,
> .extra2 = SYSCTL_TWO,
> },
> -#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
> - {
> - .procname = "binfmt_misc",
> - .mode = 0555,
> - .child = sysctl_mount_point,
> - },
> -#endif
> {
> .procname = "pipe-max-size",
> .data = &pipe_max_size,
> --
> 2.26.2
>
--
Kees Cook
