linux-stable/kernel/cgroup
Tejun Heo 1756d7994a cgroup: Use open-time credentials for process migraton perm checks
cgroup process migration permission checks are performed at write time as
whether a given operation is allowed or not is dependent on the content of
the write - the PID. This currently uses current's credentials which is a
potential security weakness as it may allow scenarios where a less
privileged process tricks a more privileged one into writing into a fd that
it created.

This patch makes both cgroup2 and cgroup1 process migration interfaces to
use the credentials saved at the time of open (file->f_cred) instead of
current's.

Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Fixes: 187fe84067 ("cgroup: require write perm on common ancestor when moving processes on the default hierarchy")
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2022-01-06 11:02:28 -10:00
..
cgroup-internal.h fs_parse: fold fs_parameter_desc/fs_parameter_spec 2020-02-07 14:48:37 -05:00
cgroup-v1.c cgroup: Use open-time credentials for process migraton perm checks 2022-01-06 11:02:28 -10:00
cgroup.c cgroup: Use open-time credentials for process migraton perm checks 2022-01-06 11:02:28 -10:00
cpuset.c mm/page_alloc: detect allocation forbidden by cpuset and bail out early 2021-11-06 13:30:38 -07:00
debug.c kernel: cgroup: fix misuse of %x 2019-05-06 08:47:48 -07:00
freezer.c cgroup: freezer: don't change task and cgroups status unnecessarily 2019-11-07 07:38:41 -08:00
legacy_freezer.c cgroup: rename freezer.c into legacy_freezer.c 2019-04-19 11:26:48 -07:00
Makefile cgroup: Add misc cgroup controller 2021-04-04 13:34:46 -04:00
misc.c misc_cgroup: remove error log to avoid log flood 2021-09-20 07:35:38 -10:00
namespace.c memcg: enable accounting for new namesapces and struct nsproxy 2021-09-03 09:58:12 -07:00
pids.c clone3: allow spawning processes into cgroups 2020-02-12 17:57:51 -05:00
rdma.c cgroup: fix spelling mistakes 2021-05-24 12:45:26 -04:00
rstat.c cgroup: Fix rootcg cpu.stat guest double counting 2021-11-01 06:47:08 -10:00