linux-hardened/fs/sysfs
Tejun Heo 3eef34ad7d kernfs: implement kernfs_get_parent(), kernfs_name/path() and friends
kernfs_node->parent and ->name are currently marked as "published"
indicating that kernfs users may access them directly; however, those
fields may get updated by kernfs_rename[_ns]() and unrestricted access
may lead to erroneous values or oops.

Protect ->parent and ->name updates with a irq-safe spinlock
kernfs_rename_lock and implement the following accessors for these
fields.

* kernfs_name()		- format the node's name into the specified buffer
* kernfs_path()		- format the node's path into the specified buffer
* pr_cont_kernfs_name()	- pr_cont a node's name (doesn't need buffer)
* pr_cont_kernfs_path()	- pr_cont a node's path (doesn't need buffer)
* kernfs_get_parent()	- pin and return a node's parent

All can be called under any context.  The recursive sysfs_pathname()
in fs/sysfs/dir.c is replaced with kernfs_path() and
sysfs_rename_dir_ns() is updated to use kernfs_get_parent() instead of
dereferencing parent directly.

v2: Dummy definition of kernfs_path() for !CONFIG_KERNFS was missing
    static inline making it cause a lot of build warnings.  Add it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-07 16:05:35 -08:00
..
dir.c kernfs: implement kernfs_get_parent(), kernfs_name/path() and friends 2014-02-07 16:05:35 -08:00
file.c sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner() 2014-02-07 15:42:41 -08:00
group.c kernfs: add @mode to kernfs_create_dir[_ns]() 2013-12-17 08:59:15 -08:00
Kconfig kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
Makefile sysfs, kernfs: move inode code to fs/kernfs/inode.c 2013-11-29 17:55:10 -08:00
mount.c kernfs: allow nodes to be created in the deactivated state 2014-02-07 15:52:48 -08:00
symlink.c kernfs: s/sysfs/kernfs/ in constants 2013-12-11 17:39:20 -08:00
sysfs.h kernfs: s/sysfs_dirent/kernfs_node/ and rename its friends accordingly 2013-12-11 15:28:36 -08:00