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

[ Upstream commit 3ca8fbabcceb8bfe44f7f50640092fd8f1de375c ]

This reverts commit 1b28cb81dab7c1eedc6034206f4e8d644046ad31.

It is

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

[ Upstream commit 3ca8fbabcceb8bfe44f7f50640092fd8f1de375c ]

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 <oliver.sang@intel.com>
Fixes: 1b28cb81dab7 ("kobject: Remove redundant checks for whether ktype is NULL")
Cc: Zhen Lei <thunder.leizhen@huawei.com>
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 <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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kobject: Remove redundant checks for whether ktype is NULL

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

kobject: Remove redundant checks for whether ktype is NULL

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 <thunder.leizhen@huawei.com>
Link: https://lore.kernel.org/r/20230805084114.1298-3-thunder.leizhen@huaweicloud.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

When I register a kset in the following way:
static struct kset my_kset;
kobject_set_name(&my_kset.kobj, "my_kset");
ret =

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

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 <thunder.leizhen@huawei.com>
Link: https://lore.kernel.org/r/20230805084114.1298-2-thunder.leizhen@huaweicloud.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: Add helper kobj_ns_type_is_valid()

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

kobject: Add helper kobj_ns_type_is_valid()

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 <thunder.leizhen@huawei.com>
Link: https://lore.kernel.org/r/20230726062508.950-1-thunder.leizhen@huaweicloud.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: Use return value of strreplace()

Since strreplace() returns the pointer to the string itself,
we may use it directly in the code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.in

kobject: Use return value of strreplace()

Since strreplace() returns the pointer to the string itself,
we may use it directly in the code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230605170553.7835-4-andriy.shevchenko@linux.intel.com

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kobject: align stacktrace levels to logging message

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
happe

kobject: align stacktrace levels to logging message

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 <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20230311-kobject-warning-v1-2-1ebba4f71fb5@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: define common logging prefix

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-

kobject: define common logging prefix

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 <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20230311-kobject-warning-v1-1-1ebba4f71fb5@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: make dynamic_kobj_ktype and kset_ktype const

Since commit ee6d3dd4ed48 ("driver core: make kobj_type constant.")
the driver core allows the usage of const struct kobj_type.

Take advantage

kobject: make dynamic_kobj_ktype and kset_ktype const

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 <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20230204-kobj_type-kobj-v1-1-ddd1b4ef8ab5@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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

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

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:
<TASK>
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 <wanghai38@huawei.com>
Link: https://lore.kernel.org/r/20221220012143.52141-1-wanghai38@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: make kobject_namespace take a const *

kobject_namespace() should take a const *kobject as it does not modify
the kobject passed to it. Change that, and the functions
kobj_child_ns_ops() an

kobject: make kobject_namespace take a const *

kobject_namespace() should take a const *kobject as it does not modify
the kobject passed to it. Change that, and the functions
kobj_child_ns_ops() and kobj_ns_ops() needed to also be changed to const
*.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20221121094649.1556002-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: make kobject_get_ownership() take a constant kobject *

The call, kobject_get_ownership(), does not modify the kobject passed
into it, so make it const. This propagates down into the kobj_t

kobject: make kobject_get_ownership() take a constant kobject *

The call, kobject_get_ownership(), does not modify the kobject passed
into it, so make it const. This propagates down into the kobj_type
function callbacks so make the kobject passed into them also const,
ensuring that nothing in the kobject is being changed here.

This helps make it more obvious what calls and callbacks do, and do not,
modify structures passed to them.

Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: linux-nfs@vger.kernel.org
Cc: bridge@lists.linux-foundation.org
Cc: netdev@vger.kernel.org
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20221121094649.1556002-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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treewide: use get_random_u32_below() instead of deprecated function

This is a simple mechanical transformation done by:

@@
expression E;
@@
- prandom_u32_max
+ get_random_u32_below
(E)

Reviewed-

treewide: use get_random_u32_below() instead of deprecated function

This is a simple mechanical transformation done by:

@@
expression E;
@@
- prandom_u32_max
+ get_random_u32_below
(E)

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Reviewed-by: SeongJae Park <sj@kernel.org> # for damon
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> # for arm
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

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kset: fix memory leak when kset_register() returns error

Inject fault while loading module, kset_register() may fail.
If it fails, the kset.kobj.name allocated by kobject_set_name()
which must be ca

kset: fix memory leak when kset_register() returns error

Inject fault while loading module, kset_register() may fail.
If it fails, the kset.kobj.name allocated by kobject_set_name()
which must be called before a call to kset_register() may be
leaked, since refcount of kobj was set in kset_init().

To mitigate this, we free the name in kset_register() when an
error is encountered, i.e. when kset_register() returns an error.

A kset may be embedded in a larger structure which may be dynamically
allocated in callers, it needs to be freed in ktype.release() or error
path in callers, in this case, we can not call kset_put() in kset_register(),
or it will cause double free, so just call kfree_const() to free the
name and set it to NULL to avoid accessing bad pointer in callers.

With this fix, the callers don't need care about freeing the name
and may call kset_put() if kset_register() fails.

Suggested-by: Luben Tuikov <luben.tuikov@amd.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: <luben.tuikov@amd.com>
Link: https://lore.kernel.org/r/20221025071549.1280528-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: modify kobject_get_path() to take a const *

kobject_get_path() does not modify the kobject passed to it, so make the
pointer constant.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: htt

kobject: modify kobject_get_path() to take a const *

kobject_get_path() does not modify the kobject passed to it, so make the
pointer constant.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20221001165315.2690141-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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treewide: use prandom_u32_max() when possible, part 1

Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
t

treewide: use prandom_u32_max() when possible, part 1

Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() >> 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

- RAND = get_random_u32();
... when != RAND
- RAND %= (E);
+ RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

((T)get_random_u32()@p & (LITERAL))

// Add one to the literal.
@script:python add_one@
literal << literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
value = int(literal, 16)
elif literal[0] in '123456789':
value = int(literal, 10)
if value is None:
print("I don't know how to handle %s" % (literal))
cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
print("Skipping 0x%x for cleanup elsewhere" % (value))
cocci.include_match(False)
elif value & (value + 1) != 0:
print("Skipping 0x%x because it's not a power of two minus one" % (value))
cocci.include_match(False)
elif literal.startswith('0x'):
coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

- (FUNC()@p & (LITERAL))
+ prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

{
- T VAR;
- VAR = (E);
- return VAR;
+ return E;
}

@drop_var@
type T;
identifier VAR;
@@

{
- T VAR;
... when != VAR
}

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: KP Singh <kpsingh@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

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kobject: kobj_type: remove default_attrs

Now that all in-kernel users of default_attrs for the kobj_type are gone
and converted to properly use the default_groups pointer instead, it can
be safely r

kobject: kobj_type: remove default_attrs

Now that all in-kernel users of default_attrs for the kobj_type are gone
and converted to properly use the default_groups pointer instead, it can
be safely removed.

There is one standard way to create sysfs files in a kobj_type, and not
two like before, causing confusion as to which should be used.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20220106133151.607703-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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driver core: make kobj_type constant.

This way instances of kobj_type (which contain function pointers) can be
stored in .rodata, which means that they cannot be [easily/accidentally]
modified at ru

driver core: make kobj_type constant.

This way instances of kobj_type (which contain function pointers) can be
stored in .rodata, which means that they cannot be [easily/accidentally]
modified at runtime.

Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Link: https://lore.kernel.org/r/20211224231345.777370-1-wedsonaf@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: unexport kobject_create() in kobject.h

The function kobject_create() is only used by one caller,
kobject_create_and_add(), no other driver uses it, nor is exported to
other modules.

Howeve

kobject: unexport kobject_create() in kobject.h

The function kobject_create() is only used by one caller,
kobject_create_and_add(), no other driver uses it, nor is exported to
other modules.

However it's still exported in kobject.h, and can sometimes confuse
users of kobject.h.

Since all users should call kobject_create_and_add(), or if extra
attributes are needed, should alloc the memory manually then call
kobject_init_and_add().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Link: https://lore.kernel.org/r/20210831093044.110729-1-wqu@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: Drop unneeded conditional in __kobject_del()

__kobject_del() is called from two places, in one where kobj is dereferenced
before and thus can't be NULL, and in the other the NULL check is d

kobject: Drop unneeded conditional in __kobject_del()

__kobject_del() is called from two places, in one where kobj is dereferenced
before and thus can't be NULL, and in the other the NULL check is done before
call. Drop unneeded conditional in __kobject_del().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20200803083520.5460-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: Restore old behaviour of kobject_del(NULL)

The commit 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in
kobject_cleanup()") inadvertently dropped a possibility to call kobjec

kobject: Restore old behaviour of kobject_del(NULL)

The commit 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in
kobject_cleanup()") inadvertently dropped a possibility to call kobject_del()
with NULL pointer. Restore the old behaviour.

Fixes: 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in kobject_cleanup()")
Cc: stable <stable@vger.kernel.org>
Reported-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Link: https://lore.kernel.org/r/20200803082706.65347-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: Avoid premature parent object freeing in kobject_cleanup()

If kobject_del() is invoked by kobject_cleanup() to delete the
target kobject, it may cause its parent kobject to be freed
before

kobject: Avoid premature parent object freeing in kobject_cleanup()

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 <naresh.kamboju@linaro.org>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Fixes: 7589238a8cf3 ("Revert "software node: Simplify software_node_release() function"")
Suggested-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/1908555.IiAGLGrh1Z@kreacher
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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 re

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

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 <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20200524153041.2361-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Revert "kobject: Make sure the parent does not get released before its children"

This reverts commit 4ef12f7198023c09ad6d25b652bd8748c965c7fa.

Guenter reports:

All my arm64be (arm64 big endian) b

Revert "kobject: Make sure the parent does not get released before its children"

This reverts commit 4ef12f7198023c09ad6d25b652bd8748c965c7fa.

Guenter reports:

All my arm64be (arm64 big endian) boot tests crash with this
patch applied. Reverting it fixes the problem. Crash log and
bisect results (from pending-fixes branch) below.

And also:
arm64 images don't crash but report lots of "poison overwritten"
backtraces like the one below. On arm, I see "refcount_t:
underflow", also attached. I didn't bisect those, but given the
context I would suspect the same culprit.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200513151840.36400-1-heikki.krogerus@linux.intel.com
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: kernel test robot <rong.a.chen@intel.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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kobject: Make sure the parent does not get released before its children

In the function kobject_cleanup(), kobject_del(kobj) is
called before the kobj->release(). That makes it possible to
release t

kobject: Make sure the parent does not get released before its children

In the function kobject_cleanup(), kobject_del(kobj) is
called before the kobj->release(). That makes it possible to
release the parent of the kobject before the kobject itself.

To fix that, adding function __kboject_del() that does
everything that kobject_del() does except release the parent
reference. kobject_cleanup() then calls __kobject_del()
instead of kobject_del(), and separately decrements the
reference count of the parent kobject after kobj->release()
has been called.

Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Fixes: 7589238a8cf3 ("Revert "software node: Simplify software_node_release() function"")
Suggested-by: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20200513151840.36400-1-heikki.krogerus@linux.intel.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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docs: filesystems: fix renamed references

Some filesystem references got broken by a previous patch
series I submitted. Address those.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.or

docs: filesystems: fix renamed references

Some filesystem references got broken by a previous patch
series I submitted. Address those.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: David Sterba <dsterba@suse.com> # fs/affs/Kconfig
Link: https://lore.kernel.org/r/57318c53008dbda7f6f4a5a9e5787f4d37e8565a.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

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