Backport summary ---------------- 1756d7994ad8 ("cgroup: Use open-time credentials for process migraton perm checks") * Cherry pick from 5.10-stable with minor contextual adjustments.
0d2b5955b362 ("cgroup: Allocate cgroup_file_ctx for kernfs_open_file->priv") * Cherry-pick from 5.10-stable, no modifications.
e57457641613 ("cgroup: Use open-time cgroup namespace for process migration perm checks") * Cherry-pick from 5.10-stable. * Backport to 5.4: drop changes to cgroup_attach_permissions() and cgroup_css_set_fork() as the two functions are not present. Also, adjust cgroup_procs_write_permission() callsites directly in cgroup_procs_write() and cgroup_threads_write().
b09c2baa5634 ("selftests: cgroup: Make cg_create() use 0755 for permission instead of 0644") * Clean cherry-pick.
613e040e4dc2 ("selftests: cgroup: Test open-time credential usage for migration checks") * Minor contextual adjustments.
bf35a7879f1d ("selftests: cgroup: Test open-time cgroup namespace usage for migration checks") * Minor contextual adjustments and added wait.h and fcntl.h includes to fix compilation.
Testing ------- The newly introduced selftests (test_cgcore_lesser_euid_open() and test_cgcore_lesser_ns_open()) pass with this series applied:
root@intel-x86-64:~# ./test_core ok 1 test_cgcore_internal_process_constraint ok 2 test_cgcore_top_down_constraint_enable ok 3 test_cgcore_top_down_constraint_disable ok 4 test_cgcore_no_internal_process_constraint_on_threads ok 5 test_cgcore_parent_becomes_threaded ok 6 test_cgcore_invalid_domain ok 7 test_cgcore_populated ok 8 test_cgcore_lesser_euid_open ok 9 test_cgcore_lesser_ns_open
Tejun Heo (6): cgroup: Use open-time credentials for process migraton perm checks cgroup: Allocate cgroup_file_ctx for kernfs_open_file->priv cgroup: Use open-time cgroup namespace for process migration perm checks selftests: cgroup: Make cg_create() use 0755 for permission instead of 0644 selftests: cgroup: Test open-time credential usage for migration checks selftests: cgroup: Test open-time cgroup namespace usage for migration checks
kernel/cgroup/cgroup-internal.h | 19 +++ kernel/cgroup/cgroup-v1.c | 33 ++-- kernel/cgroup/cgroup.c | 93 ++++++++--- tools/testing/selftests/cgroup/cgroup_util.c | 2 +- tools/testing/selftests/cgroup/test_core.c | 167 +++++++++++++++++++ 5 files changed, 271 insertions(+), 43 deletions(-)