VT_PROCESS, VT_LOCKSWITCH capabilities

[Frank Benkstein <frank-lkml@benkstein.net>]

Hi,

I wonder why there are different permissions needed for VT_PROCESS
(access to the current virtual console) and VT_LOCKSWITCH
(CAP_SYS_TTY_CONFIG).

The first one lets the calling process decide if console switching is
allowed, the second one simply disables it.  If a program wants to
forbid console switching the only technical difference I can see is that
switching is automatically reenabled when the program exits when using
VT_PROCESS.  When using VT_LOCKSWITCH it must be manually reenabled.
When the program uses the first method and disables terminal signals and
SysRQ is disabled, too, I see no practical difference between the two.

Please CC me on replies, I am not on the list.

Best regards
Frank Benkstein.