kernel/linux.git/lib/kobject.c, branch v6.19.11

kobject: Remove unused functions

2025-01-14T18:45:35+00:00

kobj_ns_initial() and kobj_ns_netlink() were adde din 2010 by commit bc451f205823 ("kobj: Add basic infrastructure for dealing with namespaces.") but have remained unused. Remove them. Signed-off-by: Dr. David Alan Gilbert Link: https://lore.kernel.org/r/20250112144907.270272-1-linux@treblig.org Signed-off-by: Greg Kroah-Hartman

Revert "kobject: Remove redundant checks for whether ktype is NULL"

2024-02-08T16:39:25+00:00

This reverts commit 1b28cb81dab7c1eedc6034206f4e8d644046ad31. It is reported to cause problems, so revert it for now until the root cause can be found. Reported-by: kernel test robot Fixes: 1b28cb81dab7 ("kobject: Remove redundant checks for whether ktype is NULL") Cc: Zhen Lei Closes: https://lore.kernel.org/oe-lkp/202402071403.e302e33a-oliver.sang@intel.com Link: https://lore.kernel.org/r/2024020849-consensus-length-6264@gregkh Signed-off-by: Greg Kroah-Hartman

kobject: Remove redundant checks for whether ktype is NULL

2023-08-19T17:37:53+00:00

When adding koject or kset, we have made sure that ktype cannot be NULL. Therefore, after adding koject or kset, there is no need to worry about ktype being NULL. Clear all ktype-related redundancy checks. Signed-off-by: Zhen Lei Link: https://lore.kernel.org/r/20230805084114.1298-3-thunder.leizhen@huaweicloud.com Signed-off-by: Greg Kroah-Hartman

kobject: Add sanity check for kset->kobj.ktype in kset_register()

2023-08-19T17:37:53+00:00

When I register a kset in the following way: static struct kset my_kset; kobject_set_name(&my_kset.kobj, "my_kset"); ret = kset_register(&my_kset); A null pointer dereference exception is occurred: [ 4453.568337] Unable to handle kernel NULL pointer dereference at \ virtual address 0000000000000028 ... ... [ 4453.810361] Call trace: [ 4453.813062] kobject_get_ownership+0xc/0x34 [ 4453.817493] kobject_add_internal+0x98/0x274 [ 4453.822005] kset_register+0x5c/0xb4 [ 4453.825820] my_kobj_init+0x44/0x1000 [my_kset] ... ... Because I didn't initialize my_kset.kobj.ktype. According to the description in Documentation/core-api/kobject.rst: - A ktype is the type of object that embeds a kobject. Every structure that embeds a kobject needs a corresponding ktype. So add sanity check to make sure kset->kobj.ktype is not NULL. Signed-off-by: Zhen Lei Link: https://lore.kernel.org/r/20230805084114.1298-2-thunder.leizhen@huaweicloud.com Signed-off-by: Greg Kroah-Hartman

kobject: Add helper kobj_ns_type_is_valid()

2023-08-05T06:31:41+00:00

There are too many "(type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES)" and "(type <= KOBJ_NS_TYPE_NONE) || (type >= KOBJ_NS_TYPES)", add helper kobj_ns_type_is_valid() to eliminate duplicate code and improve readability. Signed-off-by: Zhen Lei Link: https://lore.kernel.org/r/20230726062508.950-1-thunder.leizhen@huaweicloud.com Signed-off-by: Greg Kroah-Hartman

kobject: Use return value of strreplace()

2023-06-05T22:31:12+00:00

Since strreplace() returns the pointer to the string itself, we may use it directly in the code. Signed-off-by: Andy Shevchenko Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20230605170553.7835-4-andriy.shevchenko@linux.intel.com

kobject: align stacktrace levels to logging message

2023-03-17T14:15:23+00:00

Without an explicit level the stacktraces are printed at a default level. If this level does not match the one from the logging level it may happen that the stacktrace is shown without the message or vice versa. Both these cases are confusing, so make sure the user always sees both, the message and the stacktrace. Signed-off-by: Thomas Weißschuh Link: https://lore.kernel.org/r/20230311-kobject-warning-v1-2-1ebba4f71fb5@weissschuh.net Signed-off-by: Greg Kroah-Hartman

kobject: define common logging prefix

2023-03-17T14:15:19+00:00

All log messages start with the prefix "kobject: ". Deduplicate this by using the pr_fmt() facility. This makes the very long log strings shorter. Signed-off-by: Thomas Weißschuh Link: https://lore.kernel.org/r/20230311-kobject-warning-v1-1-1ebba4f71fb5@weissschuh.net Signed-off-by: Greg Kroah-Hartman

kobject: make dynamic_kobj_ktype and kset_ktype const

2023-02-08T12:34:20+00:00

Since commit ee6d3dd4ed48 ("driver core: make kobj_type constant.") the driver core allows the usage of const struct kobj_type. Take advantage of this to constify the structure definitions to prevent modification at runtime. Signed-off-by: Thomas Weißschuh Link: https://lore.kernel.org/r/20230204-kobj_type-kobj-v1-1-ddd1b4ef8ab5@weissschuh.net Signed-off-by: Greg Kroah-Hartman

kobject: Fix slab-out-of-bounds in fill_kobj_path()

2023-01-11T15:09:36+00:00

In kobject_get_path(), if kobj->name is changed between calls get_kobj_path_length() and fill_kobj_path() and the length becomes longer, then fill_kobj_path() will have an out-of-bounds bug. The actual current problem occurs when the ixgbe probe. In ixgbe_mii_bus_init(), if the length of netdev->dev.kobj.name length becomes longer, out-of-bounds will occur. cpu0 cpu1 ixgbe_probe register_netdev(netdev) netdev_register_kobject device_add kobject_uevent // Sending ADD events systemd-udevd // rename netdev dev_change_name device_rename kobject_rename ixgbe_mii_bus_init | mdiobus_register | __mdiobus_register | device_register | device_add | kobject_uevent | kobject_get_path | len = get_kobj_path_length // old name | path = kzalloc(len, gfp_mask); | kobj->name = name; /* name length becomes * longer */ fill_kobj_path /* kobj path length is * longer than path, * resulting in out of * bounds when filling path */ This is the kasan report: ================================================================== BUG: KASAN: slab-out-of-bounds in fill_kobj_path+0x50/0xc0 Write of size 7 at addr ff1100090573d1fd by task kworker/28:1/673 Workqueue: events work_for_cpu_fn Call Trace: dump_stack_lvl+0x34/0x48 print_address_description.constprop.0+0x86/0x1e7 print_report+0x36/0x4f kasan_report+0xad/0x130 kasan_check_range+0x35/0x1c0 memcpy+0x39/0x60 fill_kobj_path+0x50/0xc0 kobject_get_path+0x5a/0xc0 kobject_uevent_env+0x140/0x460 device_add+0x5c7/0x910 __mdiobus_register+0x14e/0x490 ixgbe_probe.cold+0x441/0x574 [ixgbe] local_pci_probe+0x78/0xc0 work_for_cpu_fn+0x26/0x40 process_one_work+0x3b6/0x6a0 worker_thread+0x368/0x520 kthread+0x165/0x1a0 ret_from_fork+0x1f/0x30 This reproducer triggers that bug: while: do rmmod ixgbe sleep 0.5 modprobe ixgbe sleep 0.5 When calling fill_kobj_path() to fill path, if the name length of kobj becomes longer, return failure and retry. This fixes the problem. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Wang Hai Link: https://lore.kernel.org/r/20221220012143.52141-1-wanghai38@huawei.com Signed-off-by: Greg Kroah-Hartman