There are objects in /sys hierarchy (/sys/class/net/) that logically belong to a namespace/container. Unfortunately all sysfs objects start their life belonging to global root, and while we could change ownership manually, keeping tracks of all objects that come and go is cumbersome. It would be better if kernel created them using correct uid/gid from the beginning.
This series changes kernfs to allow creating object's with arbitrary uid/gid, adds get_ownership() callback to ktype structure so subsystems could supply their own logic (likely tied to namespace support) for determining ownership of kobjects, and adjusts sysfs code to make use of this information. Lastly net-sysfs is adjusted to make sure that objects in net namespace are owned by the root user from the owning user namespace. Note that we do not adjust ownership of objects moved into a new namespace (as when moving a network device into a container) as userspace can easily do it. Thanks! Dmitry Torokhov (5): kernfs: allow creating kernfs objects with arbitrary uid/gid sysfs, kobject: allow creating kobject belonging to arbitrary users kobject: kset_create_and_add() - fetch ownership info from parent driver core: set up ownership of class devices in sysfs net-sysfs: make sure objects belong to contrainer's owner drivers/base/core.c | 9 +++++++++ fs/kernfs/dir.c | 29 ++++++++++++++++++++++++++--- fs/kernfs/file.c | 8 ++++++-- fs/kernfs/inode.c | 2 +- fs/kernfs/kernfs-internal.h | 2 ++ fs/kernfs/symlink.c | 11 ++++++++++- fs/sysfs/dir.c | 7 ++++++- fs/sysfs/file.c | 33 +++++++++++++++++++++------------ fs/sysfs/group.c | 23 +++++++++++++++++------ fs/sysfs/sysfs.h | 3 ++- include/linux/device.h | 5 +++++ include/linux/kernfs.h | 28 +++++++++++++++++++--------- include/linux/kobject.h | 4 ++++ kernel/cgroup.c | 4 +++- lib/kobject.c | 28 +++++++++++++++++++++++++++- net/core/net-sysfs.c | 44 +++++++++++++++++++++++++++++++++++++++++++- 16 files changed, 201 insertions(+), 39 deletions(-) -- 2.8.0.rc3.226.g39d4020
