Pull misc VFS updates from Al Viro:
"VFS-related cleanups in various places (mostly of the "that really
can't happen" or "there's a better way to do it" variety)"
* tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
gpib: use file_inode()
binder_ioctl_write_read(): simplify control flow a bit
secretmem: move setting O_LARGEFILE and bumping users' count to the place where we create the file
apparmor: file never has NULL f_path.mnt
landlock: opened file never has a negative dentry
Each case tested by the binder allocator test is defined by 3 parameters:
the end alignment type of each requested buffer allocation, whether those
buffers share the front or back pages of the allotted address space, and
the order in which those buffers should be released. The alignment type
represents how a binder buffer may be laid out within or across page
boundaries and relative to other buffers, and it's used along with
whether the buffers cover part (sharing the front pages) of or all
(sharing the back pages) of the vma to calculate the sizes passed into
each test.
binder_alloc_test_alloc recursively generates each possible arrangement
of alignment types and then tests that the binder_alloc code tracks pages
correctly when those buffers are allocated and then freed in every
possible order at both ends of the address space. While they provide
comprehensive coverage, they are poor candidates to be represented as
KUnit test cases, which must be statically enumerated. For 5 buffers and
5 end alignment types, the test case array would have 750,000 entries.
This change structures the recursive calls into meaningful test cases so
that failures are easier to interpret.
Signed-off-by: Tiffany Yang <ynaffit@google.com>
Acked-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20250714185321.2417234-7-ynaffit@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert the existing binder_alloc_selftest tests into KUnit tests. These
tests allocate and free an exhaustive combination of buffers with
various sizes and alignments. This change allows them to be run without
blocking or otherwise interfering with other processes in binder.
This test is refactored into more meaningful cases in the subsequent
patch.
Signed-off-by: Tiffany Yang <ynaffit@google.com>
Acked-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20250714185321.2417234-6-ynaffit@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Store a pointer to the free pages list that the binder allocator should
use for a process inside of struct binder_alloc. This change allows
binder allocator code to be tested and debugged deterministically while
a system is using binder; i.e., without interfering with other binder
processes and independently of the shrinker. This is necessary to
convert the current binder_alloc_selftest into a kunit test that does
not rely on hijacking an existing binder_proc to run.
A binder process's binder_alloc->freelist should not be changed after
it is initialized. A sole exception is the process that runs the
existing binder_alloc selftest. Its freelist can be temporarily replaced
for the duration of the test because it runs as a single thread before
any pages can be added to the global binder freelist, and the test frees
every page it allocates before dropping the binder_selftest_lock. This
exception allows the existing selftest to be used to check for
regressions, but it will be dropped when the binder_alloc tests are
converted to kunit in a subsequent patch in this series.
Signed-off-by: Tiffany Yang <ynaffit@google.com>
Acked-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20250714185321.2417234-3-ynaffit@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
don't try to open-code simple_recursive_removal(), especially when
you miss things like d_invalidate()...
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull char / misc / iio driver updates from Greg KH:
"Here is the big char/misc/iio and other small driver subsystem pull
request for 6.16-rc1.
Overall, a lot of individual changes, but nothing major, just the
normal constant forward progress of new device support and cleanups to
existing subsystems. Highlights in here are:
- Large IIO driver updates and additions and device tree changes
- Android binder bugfixes and logfile fixes
- mhi driver updates
- comedi driver updates
- counter driver updates and additions
- coresight driver updates and additions
- echo driver removal as there are no in-kernel users of it
- nvmem driver updates
- spmi driver updates
- new amd-sbi driver "subsystem" and drivers added
- rust miscdriver binding documentation fix
- other small driver fixes and updates (uio, w1, acrn, hpet,
xillybus, cardreader drivers, fastrpc and others)
All of these have been in linux-next for quite a while with no
reported problems"
* tag 'char-misc-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (390 commits)
binder: fix yet another UAF in binder_devices
counter: microchip-tcb-capture: Add watch validation support
dt-bindings: iio: adc: Add ROHM BD79100G
iio: adc: add support for Nuvoton NCT7201
dt-bindings: iio: adc: add NCT7201 ADCs
iio: chemical: Add driver for SEN0322
dt-bindings: trivial-devices: Document SEN0322
iio: adc: ad7768-1: reorganize driver headers
iio: bmp280: zero-init buffer
iio: ssp_sensors: optimalize -> optimize
HID: sensor-hub: Fix typo and improve documentation
iio: admv1013: replace redundant ternary operator with just len
iio: chemical: mhz19b: Fix error code in probe()
iio: adc: at91-sama5d2: use IIO_DECLARE_BUFFER_WITH_TS
iio: accel: sca3300: use IIO_DECLARE_BUFFER_WITH_TS
iio: adc: ad7380: use IIO_DECLARE_DMA_BUFFER_WITH_TS
iio: adc: ad4695: rename AD4695_MAX_VIN_CHANNELS
iio: adc: ad4695: use IIO_DECLARE_DMA_BUFFER_WITH_TS
iio: introduce IIO_DECLARE_BUFFER_WITH_TS macros
iio: make IIO_DMA_MINALIGN minimum of 8 bytes
...
Pull vfs directory lookup updates from Christian Brauner:
"This contains cleanups for the lookup_one*() family of helpers.
We expose a set of functions with names containing "lookup_one_len"
and others without the "_len". This difference has nothing to do with
"len". It's rater a historical accident that can be confusing.
The functions without "_len" take a "mnt_idmap" pointer. This is found
in the "vfsmount" and that is an important question when choosing
which to use: do you have a vfsmount, or are you "inside" the
filesystem. A related question is "is permission checking relevant
here?".
nfsd and cachefiles *do* have a vfsmount but *don't* use the non-_len
functions. They pass nop_mnt_idmap and refuse to work on filesystems
which have any other idmap.
This work changes nfsd and cachefile to use the lookup_one family of
functions and to explictily pass &nop_mnt_idmap which is consistent
with all other vfs interfaces used where &nop_mnt_idmap is explicitly
passed.
The remaining uses of the "_one" functions do not require permission
checks so these are renamed to be "_noperm" and the permission
checking is removed.
This series also changes these lookup function to take a qstr instead
of separate name and len. In many cases this simplifies the call"
* tag 'vfs-6.16-rc1.async.dir' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
VFS: change lookup_one_common and lookup_noperm_common to take a qstr
Use try_lookup_noperm() instead of d_hash_and_lookup() outside of VFS
VFS: rename lookup_one_len family to lookup_noperm and remove permission check
cachefiles: Use lookup_one() rather than lookup_one_len()
nfsd: Use lookup_one() rather than lookup_one_len()
VFS: improve interface for lookup_one functions
Commit e77aff5528 ("binderfs: fix use-after-free in binder_devices")
addressed a use-after-free where devices could be released without first
being removed from the binder_devices list. However, there is a similar
path in binder_free_proc() that was missed:
==================================================================
BUG: KASAN: slab-use-after-free in binder_remove_device+0xd4/0x100
Write of size 8 at addr ffff0000c773b900 by task umount/467
CPU: 12 UID: 0 PID: 467 Comm: umount Not tainted 6.15.0-rc7-00138-g57483a362741 #9 PREEMPT
Hardware name: linux,dummy-virt (DT)
Call trace:
binder_remove_device+0xd4/0x100
binderfs_evict_inode+0x230/0x2f0
evict+0x25c/0x5dc
iput+0x304/0x480
dentry_unlink_inode+0x208/0x46c
__dentry_kill+0x154/0x530
[...]
Allocated by task 463:
__kmalloc_cache_noprof+0x13c/0x324
binderfs_binder_device_create.isra.0+0x138/0xa60
binder_ctl_ioctl+0x1ac/0x230
[...]
Freed by task 215:
kfree+0x184/0x31c
binder_proc_dec_tmpref+0x33c/0x4ac
binder_deferred_func+0xc10/0x1108
process_one_work+0x520/0xba4
[...]
==================================================================
Call binder_remove_device() within binder_free_proc() to ensure the
device is removed from the binder_devices list before being kfreed.
Cc: stable@vger.kernel.org
Fixes: 12d909cac1 ("binderfs: add new binder devices to binder_devices")
Reported-by: syzbot+4af454407ec393de51d6@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=4af454407ec393de51d6
Tested-by: syzbot+4af454407ec393de51d6@syzkaller.appspotmail.com
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20250524220758.915028-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Binder defines several seq_files that can be accessed via debugfs or
binderfs. Some of these files (e.g., 'state' and 'transactions')
contain more granular information about binder's internal state that
is helpful for debugging, but they also leak userspace address data
through user-defined 'cookie' or 'ptr' values. Consequently, access
to these files must be heavily restricted.
Add two new files, 'state_hashed' and 'transactions_hashed', that
reproduce the information in the original files but use the kernel's
raw pointer obfuscation to hash any potential user addresses. This
approach allows systems to grant broader access to the new files
without having to change the security policy around the existing ones.
In practice, userspace populates these fields with user addresses, but
within the driver, these values only serve as unique identifiers for
their associated binder objects. Consequently, binder logs can
obfuscate these values and still retain meaning. While this strategy
prevents leaking information about the userspace memory layout in the
existing log files, it also decouples log messages about binder
objects from their user-defined identifiers.
Acked-by: Carlos Llamas <cmllamas@google.com>
Tested-by: Carlos Llamas <cmllamas@google.com>
Signed-off-by: "Tiffany Y. Yang" <ynaffit@google.com>
Link: https://lore.kernel.org/r/20250510013435.1520671-7-ynaffit@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The binder driver outputs information about each dead binder node by
iterating over the dead nodes list, and it prints the state of each live
node in the system by traversing each binder_proc's proc->nodes tree.
Both cases require similar logic to maintain the global lock ordering
while accessing each node.
Create a helper function to synchronize around printing binder nodes in
a list. Opportunistically make minor cosmetic changes to binder print
functions.
Acked-by: Carlos Llamas <cmllamas@google.com>
Signed-off-by: "Tiffany Y. Yang" <ynaffit@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250510013435.1520671-5-ynaffit@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The lookup_one_len family of functions is (now) only used internally by
a filesystem on itself either
- in a context where permission checking is irrelevant such as by a
virtual filesystem populating itself, or xfs accessing its ORPHANAGE
or dquota accessing the quota file; or
- in a context where a permission check (MAY_EXEC on the parent) has just
been performed such as a network filesystem finding in "silly-rename"
file in the same directory. This is also the context after the
_parentat() functions where currently lookup_one_qstr_excl() is used.
So the permission check is pointless.
The name "one_len" is unhelpful in understanding the purpose of these
functions and should be changed. Most of the callers pass the len as
"strlen()" so using a qstr and QSTR() can simplify the code.
This patch renames these functions (include lookup_positive_unlocked()
which is part of the family despite the name) to have a name based on
"lookup_noperm". They are changed to receive a 'struct qstr' instead
of separate name and len. In a few cases the use of QSTR() results in a
new call to strlen().
try_lookup_noperm() takes a pointer to a qstr instead of the whole
qstr. This is consistent with d_hash_and_lookup() (which is nearly
identical) and useful for lookup_noperm_unlocked().
The new lookup_noperm_common() doesn't take a qstr yet. That will be
tidied up in a subsequent patch.
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://lore.kernel.org/r/20250319031545.2999807-5-neil@brown.name
Signed-off-by: Christian Brauner <brauner@kernel.org>
