Re: [PATCH] ioctl_console: Document new CAP_SYS_ADMIN restrictions (since Linux 6.7)

[Alejandro Colomar <alx@kernel.org>]

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Hi Günther, Greg,

On Fri, Dec 01, 2023 at 01:26:45PM +0100, Günther Noack wrote:
> Since Linux commit 8d1b43f6a6df7bce ("tty: Restrict access to TIOCLINUX'
> copy-and-paste subcommands"), the TIOCL_SETSEL, TIOCL_PASTESEL and
> TIOCL_SELLOADLUT subcommands require CAP_SYS_ADMIN.
> 
> Cc: Hanno Böck <hanno@hboeck.de>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Günther Noack <gnoack@google.com>
> ---
>  man2/ioctl_console.2 | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/man2/ioctl_console.2 b/man2/ioctl_console.2
> index 684b4d013..abc50b786 100644
> --- a/man2/ioctl_console.2
> +++ b/man2/ioctl_console.2
> @@ -715,12 +715,20 @@ is 0 for character-by-character selection,
>  or 2 for line-by-line selection.
>  The indicated screen characters are highlighted and saved
>  in a kernel buffer.
> +.IP
> +Since Linux 6.7, using this subcode requires the

Are these requirements expected to be backported to stable kernels?

Cheers,
Alex

> +.B CAP_SYS_ADMIN
> +capability.
>  .TP
>  .BR TIOCLINUX ", " subcode = TIOCL_PASTESEL
>  Paste selection.
>  The characters in the selection buffer are
>  written to
>  .IR fd .
> +.IP
> +Since Linux 6.7, using this subcode requires the
> +.B CAP_SYS_ADMIN
> +capability.
>  .TP
>  .BR TIOCLINUX ", " subcode = TIOCL_UNBLANKSCREEN
>  Unblank the screen.
> @@ -729,6 +737,10 @@ Unblank the screen.
>  Sets contents of a 256-bit look up table defining characters in a "word",
>  for word-by-word selection.
>  (Since Linux 1.1.32.)
> +.IP
> +Since Linux 6.7, using this subcode requires the
> +.B CAP_SYS_ADMIN
> +capability.
>  .TP
>  .BR TIOCLINUX ", " subcode = TIOCL_GETSHIFTSTATE
>  .I argp
> -- 
> 2.43.0.rc2.451.g8631bc7472-goog
> 

-- 
<https://www.alejandro-colomar.es/>

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