user/sven/linux.git/lib/kobject.c, branch v5.8.2

kobject: Avoid premature parent object freeing in kobject_cleanup()

2020-08-19T06:26:33Z

[ Upstream commit 079ad2fb4bf9eba8a0aaab014b49705cd7f07c66 ] If kobject_del() is invoked by kobject_cleanup() to delete the target kobject, it may cause its parent kobject to be freed before invoking the target kobject's ->release() method, which effectively means freeing the parent before dealing with the child entirely. That is confusing at best and it may also lead to functional issues if the callers of kobject_cleanup() are not careful enough about the order in which these calls are made, so avoid the problem by making kobject_cleanup() drop the last reference to the target kobject's parent at the end, after invoking the target kobject's ->release() method. [ rjw: Rewrite the subject and changelog, make kobject_cleanup() drop the parent reference only when __kobject_del() has been called. ] Reported-by: Naresh Kamboju Reported-by: kernel test robot Fixes: 7589238a8cf3 ("Revert "software node: Simplify software_node_release() function"") Suggested-by: Rafael J. Wysocki Signed-off-by: Heikki Krogerus Signed-off-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/1908555.IiAGLGrh1Z@kreacher Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

Merge tag 'driver-core-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2020-06-07T17:53:36Z

Pull driver core updates from Greg KH: "Here is the set of driver core patches for 5.8-rc1. Not all that huge this release, just a number of small fixes and updates: - software node fixes - kobject now sends KOBJ_REMOVE when it is removed from sysfs, not when it is removed from memory (which could come much later) - device link additions and fixes based on testing on more devices - firmware core cleanups - other minor changes, full details in the shortlog All have been in linux-next for a while with no reported issues" * tag 'driver-core-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits) driver core: Update device link status correctly for SYNC_STATE_ONLY links firmware_loader: change enum fw_opt to u32 software node: implement software_node_unregister() kobject: send KOBJ_REMOVE uevent when the object is removed from sysfs driver core: Remove unnecessary is_fwnode_dev variable in device_add() drivers property: When no children in primary, try secondary driver core: platform: Fix spelling errors in platform.c driver core: Remove check in driver_deferred_probe_force_trigger() of: platform: Batch fwnode parsing when adding all top level devices driver core: fw_devlink: Add support for batching fwnode parsing driver core: Look for waiting consumers only for a fwnode's primary device driver core: Move code to the right part of the file Revert "Revert "driver core: Set fw_devlink to "permissive" behavior by default"" drivers: base: Fix NULL pointer exception in __platform_driver_probe() if a driver developer is foolish firmware_loader: move fw_fallback_config to a private kernel symbol namespace driver core: Add missing '\n' in log messages driver/base/soc: Use kobj_to_dev() API Add documentation on meaning of -EPROBE_DEFER driver core: platform: remove redundant assignment to variable ret debugfs: Use the correct style for SPDX License Identifier ...

kobject: send KOBJ_REMOVE uevent when the object is removed from sysfs

2020-05-25T12:49:22Z

It is possible for a KOBJ_REMOVE uevent to be sent to userspace way after the files are actually gone from sysfs, due to how reference counting for kobjects work. This should not be a problem, but it would be good to properly send the information when things are going away, not at some later point in time in the future. Before this move, if a kobject's parent was torn down before the child, when the call to kobject_uevent() happened, the parent walk to try to reconstruct the full path of the kobject could be a total mess and cause crashes. It's not good to try to tear down a kobject tree from top down, but let's at least try to not to crash if a user does so. Reviewed-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20200524153041.2361-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

docs: filesystems: fix renamed references

2020-04-20T21:45:22Z

Some filesystem references got broken by a previous patch series I submitted. Address those. Signed-off-by: Mauro Carvalho Chehab Acked-by: David Sterba # fs/affs/Kconfig Link: https://lore.kernel.org/r/57318c53008dbda7f6f4a5a9e5787f4d37e8565a.1586881715.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet

lib : kobject: fix refcount imblance on kobject_rename

2019-06-19T17:27:39Z

the kobj refcount increased by kobject_get should be released before error return, otherwise lead to a memory leak. Signed-off-by: Lin Yi Signed-off-by: Greg Kroah-Hartman

kobject: clean up the kobject add documentation a bit more

2019-05-03T06:26:51Z

Commit 1fd7c3b438a2 ("kobject: Improve doc clarity kobject_init_and_add()") tried to provide more clarity, but the reference to kobject_del() was incorrect. Fix that up by removing that line, and hopefully be more explicit as to exactly what needs to happen here once you register a kobject with the kobject core. Acked-by: Tobin C. Harding Fixes: 1fd7c3b438a2 ("kobject: Improve doc clarity kobject_init_and_add()") Signed-off-by: Greg Kroah-Hartman

kobject: Fix kernel-doc comment first line

2019-05-02T07:28:18Z

kernel-doc comments have a prescribed format. This includes parenthesis on the function name. To be _particularly_ correct we should also capitalise the brief description and terminate it with a period. In preparation for adding/updating kernel-doc function comments clean up the ones currently present. Signed-off-by: Tobin C. Harding Signed-off-by: Greg Kroah-Hartman

kobject: Remove docstring reference to kset

2019-05-02T07:24:06Z

Currently the docstring for kobject_get_path() mentions 'kset'. The kset is not used in the function callchain starting from this function. Remove docstring reference to kset from the function kobject_get_path(). Signed-off-by: Tobin C. Harding Signed-off-by: Greg Kroah-Hartman

kobject: fix dereference before null check on kobj

2019-05-01T13:08:38Z

The kobj pointer is being null-checked so potentially it could be null, however, the ktype declaration before the null check is dereferencing kobj hence we have a potential null pointer deference. Fix this by moving the assignment of ktype after kobj has been null checked. Addresses-Coverity: ("Dereference before null check") Fixes: aa30f47cf666 ("kobject: Add support for default attribute groups to kobj_type") Signed-off-by: Colin Ian King Signed-off-by: Greg Kroah-Hartman

kobject: Improve doc clarity kobject_init_and_add()

2019-04-28T16:16:03Z

Function kobject_init_and_add() is currently misused in a number of places in the kernel. On error return kobject_put() must be called but is at times not. Make the function documentation more explicit about calling kobject_put() in the error path. Signed-off-by: Tobin C. Harding Signed-off-by: Greg Kroah-Hartman