tree 1244b7cf2755c06a8a793149ce4717e4a1311218
parent 9e3bd6c3fb2334be171e69b432039cd18bce4458
author Oleg Nesterov <oleg@tv-sign.ru> 1209541962 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1209569374 -0700

signals: cleanup security_task_kill() usage/implementation

Every implementation of ->task_kill() does nothing when the signal comes from
the kernel.  This is correct, but means that check_kill_permission() should
call security_task_kill() only for SI_FROMUSER() case, and we can remove the
same check from ->task_kill() implementations.

(sadly, check_kill_permission() is the last user of signal->session/__session
 but we can't s/task_session_nr/task_session/ here).

NOTE: Eric W.  Biederman pointed out cap_task_kill() should die, and I think
he is very right.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: David Quigley <dpquigl@tycho.nsa.gov>
Cc: Eric Paris <eparis@redhat.com>
Cc: Harald Welte <laforge@gnumonks.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>