ANDROID: cgroup: Add generic cgroup subsystem permission checks
Rather than using explicit euid == 0 checks when trying to move
tasks into a cgroup via CFS, move permission checks into each
specific cgroup subsystem. If a subsystem does not specify a
'allow_attach' handler, then we fall back to doing our checks
the old way.
Use the 'allow_attach' handler for the 'cpu' cgroup to allow
non-root processes to add arbitrary processes to a 'cpu' cgroup
if it has the CAP_SYS_NICE capability set.
This version of the patch adds a 'allow_attach' handler instead
of reusing the 'can_attach' handler. If the 'can_attach' handler
is reused, a new cgroup that implements 'can_attach' but not
the permission checks could end up with no permission checks
at all.
Includes fixes/maintenance by the following people:
Christian Poetzsch <christian.potzsch@imgtec.com>:
Fix generic cgroup subsystem permission checks
Dmitry Shmidt <dimitrysh@google.com>:
cgroup: fix cgroup_taskset_for_each call in allow_attach() for 4.1
Amit Pundir <amit.pundir@linaro.org>
cgroup: refactor allow_attach handler for 4.4
Original-Author: San Mehat <san@google.com>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Christian Poetzsch <christian.potzsch@imgtec.com>
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
BUG: 18260435
Patchset: cgroup-permission-checks
Signed-off-by: Mattias Nissler <mnissler@google.com>
Change-Id: I41e6bd0811879085437175e8bbaea09c7be3ba1e
3 files changed
