This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Pull char/misc/IIO driver updates from Greg KH:
"Here is the big set of char/misc/iio and other smaller driver
subsystem changes for 7.0-rc1. Lots of little things in here,
including:
- Loads of iio driver changes and updates and additions
- gpib driver updates
- interconnect driver updates
- i3c driver updates
- hwtracing (coresight and intel) driver updates
- deletion of the obsolete mwave driver
- binder driver updates (rust and c versions)
- mhi driver updates (causing a merge conflict, see below)
- mei driver updates
- fsi driver updates
- eeprom driver updates
- lots of other small char and misc driver updates and cleanups
All of these have been in linux-next for a while, with no reported
issues"
* tag 'char-misc-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (297 commits)
mux: mmio: fix regmap leak on probe failure
rust_binder: return p from rust_binder_transaction_target_node()
drivers: android: binder: Update ARef imports from sync::aref
rust_binder: fix needless borrow in context.rs
iio: magn: mmc5633: Fix Kconfig for combination of I3C as module and driver builtin
iio: sca3000: Fix a resource leak in sca3000_probe()
iio: proximity: rfd77402: Add interrupt handling support
iio: proximity: rfd77402: Document device private data structure
iio: proximity: rfd77402: Use devm-managed mutex initialization
iio: proximity: rfd77402: Use kernel helper for result polling
iio: proximity: rfd77402: Align polling timeout with datasheet
iio: cros_ec: Allow enabling/disabling calibration mode
iio: frequency: ad9523: correct kernel-doc bad line warning
iio: buffer: buffer_impl.h: fix kernel-doc warnings
iio: gyro: itg3200: Fix unchecked return value in read_raw
MAINTAINERS: add entry for ADE9000 driver
iio: accel: sca3000: remove unused last_timestamp field
iio: accel: adxl372: remove unused int2_bitmask field
iio: adc: ad7766: Use iio_trigger_generic_data_rdy_poll()
iio: magnetometer: Remove IRQF_ONESHOT
...
Pull non-MM updates from Andrew Morton:
- "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves
disk space by teaching ocfs2 to reclaim suballocator block group
space (Heming Zhao)
- "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the
ARRAY_END() macro and uses it in various places (Alejandro Colomar)
- "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes
the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the
page size (Pnina Feder)
- "kallsyms: Prevent invalid access when showing module buildid" cleans
up kallsyms code related to module buildid and fixes an invalid
access crash when printing backtraces (Petr Mladek)
- "Address page fault in ima_restore_measurement_list()" fixes a
kexec-related crash that can occur when booting the second-stage
kernel on x86 (Harshit Mogalapalli)
- "kho: ABI headers and Documentation updates" updates the kexec
handover ABI documentation (Mike Rapoport)
- "Align atomic storage" adds the __aligned attribute to atomic_t and
atomic64_t definitions to get natural alignment of both types on
csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain)
- "kho: clean up page initialization logic" simplifies the page
initialization logic in kho_restore_page() (Pratyush Yadav)
- "Unload linux/kernel.h" moves several things out of kernel.h and into
more appropriate places (Yury Norov)
- "don't abuse task_struct.group_leader" removes the usage of
->group_leader when it is "obviously unnecessary" (Oleg Nesterov)
- "list private v2 & luo flb" adds some infrastructure improvements to
the live update orchestrator (Pasha Tatashin)
* tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits)
watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency
procfs: fix missing RCU protection when reading real_parent in do_task_stat()
watchdog/softlockup: fix sample ring index wrap in need_counting_irqs()
kcsan, compiler_types: avoid duplicate type issues in BPF Type Format
kho: fix doc for kho_restore_pages()
tests/liveupdate: add in-kernel liveupdate test
liveupdate: luo_flb: introduce File-Lifecycle-Bound global state
liveupdate: luo_file: Use private list
list: add kunit test for private list primitives
list: add primitives for private list manipulations
delayacct: fix uapi timespec64 definition
panic: add panic_force_cpu= parameter to redirect panic to a specific CPU
netclassid: use thread_group_leader(p) in update_classid_task()
RDMA/umem: don't abuse current->group_leader
drm/pan*: don't abuse current->group_leader
drm/amd: kill the outdated "Only the pthreads threading model is supported" checks
drm/amdgpu: don't abuse current->group_leader
android/binder: use same_thread_group(proc->tsk, current) in binder_mmap()
android/binder: don't abuse current->group_leader
kho: skip memoryless NUMA nodes when reserving scratch areas
...
Oneway transactions sent to frozen targets via binder_proc_transaction()
return a BR_TRANSACTION_PENDING_FROZEN error but they are still treated
as successful since the target is expected to thaw at some point. It is
then not safe to access 't' after BR_TRANSACTION_PENDING_FROZEN errors
as the transaction could have been consumed by the now thawed target.
This is the case for binder_netlink_report() which derreferences 't'
after a pending frozen error, as pointed out by the following KASAN
report:
==================================================================
BUG: KASAN: slab-use-after-free in binder_netlink_report.isra.0+0x694/0x6c8
Read of size 8 at addr ffff00000f98ba38 by task binder-util/522
CPU: 4 UID: 0 PID: 522 Comm: binder-util Not tainted 6.19.0-rc6-00015-gc03e9c42ae8f #1 PREEMPT
Hardware name: linux,dummy-virt (DT)
Call trace:
binder_netlink_report.isra.0+0x694/0x6c8
binder_transaction+0x66e4/0x79b8
binder_thread_write+0xab4/0x4440
binder_ioctl+0x1fd4/0x2940
[...]
Allocated by task 522:
__kmalloc_cache_noprof+0x17c/0x50c
binder_transaction+0x584/0x79b8
binder_thread_write+0xab4/0x4440
binder_ioctl+0x1fd4/0x2940
[...]
Freed by task 488:
kfree+0x1d0/0x420
binder_free_transaction+0x150/0x234
binder_thread_read+0x2d08/0x3ce4
binder_ioctl+0x488/0x2940
[...]
==================================================================
Instead, make a transaction copy so the data can be safely accessed by
binder_netlink_report() after a pending frozen error. While here, add a
comment about not using t->buffer in binder_netlink_report().
Cc: stable@vger.kernel.org
Fixes: 63740349eb ("binder: introduce transaction reports via netlink")
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260122180203.1502637-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the past %pK was preferable to %p as it would not leak raw pointer
values into the kernel log. Since commit ad67b74d24 ("printk: hash
addresses printed with %p") the regular %p has been improved to avoid
this issue. Furthermore, restricted pointers ("%pK") were never meant
to be used through printk(). They can still unintentionally leak raw
pointers or acquire sleeping locks in atomic contexts.
Switch to the regular pointer formatting which is safer and
easier to reason about.
There are still a few users of %pK left, but these use it through
seq_file, for which its usage is safe.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260107-restricted-pointers-binder-v1-1-181018bf3812@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are no scenarios where a weak increment is invalid on binder_node.
The only possible case where it could be invalid is if the kernel
delivers BR_DECREFS to the process that owns the node, and then
increments the weak refcount again, effectively "reviving" a dead node.
However, that is not possible: when the BR_DECREFS command is delivered,
the kernel removes and frees the binder_node. The fact that you were
able to call binder_inc_node_nilocked() implies that the node is not yet
destroyed, which implies that BR_DECREFS has not been delivered to
userspace, so incrementing the weak refcount is valid.
Note that it's currently possible to trigger this condition if the owner
calls BINDER_THREAD_EXIT while node->has_weak_ref is true. This causes
BC_INCREFS on binder_ref instances to fail when they should not.
Cc: stable@vger.kernel.org
Fixes: 457b9a6f09 ("Staging: android: add binder driver")
Reported-by: Yu-Ting Tseng <yutingtseng@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20251015-binder-weak-inc-v1-1-7914b092c371@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix several kernel-doc warnings in `drivers/android/binder.c` caused by
undocumented struct members and function parameters.
In particular, add missing documentation for the `@thread` parameter in
binder_free_buf_locked().
Signed-off-by: Kriish Sharma <kriish.sharma2006@gmail.com>
Acked-by: Carlos Llamas <cmllamas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce a generic netlink multicast event to report binder transaction
failures to userspace. This allows subscribers to monitor these events
and take appropriate actions, such as stopping a misbehaving application
that is spamming a service with huge amount of transactions.
The multicast event contains full details of the failed transactions,
including the sender/target PIDs, payload size and specific error code.
This interface is defined using a YAML spec, from which the UAPI and
kernel headers and source are auto-generated.
Signed-off-by: Li Li <dualli@google.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20250727182932.2499194-4-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace the t->need_reply flag with the more descriptive t->is_async and
and t->is_reply flags. The 'need_reply' flag was only used for debugging
purposes and the new flags can be used to distinguish between the type
of transactions too: sync, async and reply.
For now, only update the logging in print_binder_transaction_ilocked().
However, the new flags can be used in the future to replace the current
patterns and improve readability. e.g.:
- if (!reply && !(tr->flags & TF_ONE_WAY))
+ if (t->is_async)
This patch is in preparation for binder's generic netlink implementation
and no functional changes are intended.
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20250727182932.2499194-3-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the allocation of 'struct binder_transaction' to the beginning of
the binder_transaction() function, along with the initialization of all
the members that are known at that time. This minor refactoring helps to
consolidate the usage of transaction information at later points.
This patch is in preparation for binder's generic netlink implementation
and no functional changes are intended.
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20250727182932.2499194-2-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull char / misc / IIO / other driver updates from Greg KH:
"Here is the big set of char/misc/iio and other smaller driver
subsystems for 6.17-rc1. It's a big set this time around, with the
huge majority being in the iio subsystem with new drivers and dts
files being added there.
Highlights include:
- IIO driver updates, additions, and changes making more code const
and cleaning up some init logic
- bus_type constant conversion changes
- misc device test functions added
- rust miscdevice minor fixup
- unused function removals for some drivers
- mei driver updates
- mhi driver updates
- interconnect driver updates
- Android binder updates and test infrastructure added
- small cdx driver updates
- small comedi fixes
- small nvmem driver updates
- small pps driver updates
- some acrn virt driver fixes for printk messages
- other small driver updates
All of these have been in linux-next with no reported issues"
* tag 'char-misc-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits)
binder: Use seq_buf in binder_alloc kunit tests
binder: Add copyright notice to new kunit files
misc: ti_fpc202: Switch to of_fwnode_handle()
bus: moxtet: Use dev_fwnode()
pc104: move PC104 option to drivers/Kconfig
drivers: virt: acrn: Don't use %pK through printk
comedi: fix race between polling and detaching
interconnect: qcom: Add Milos interconnect provider driver
dt-bindings: interconnect: document the RPMh Network-On-Chip Interconnect in Qualcomm Milos SoC
mei: more prints with client prefix
mei: bus: use cldev in prints
bus: mhi: host: pci_generic: Add Telit FN990B40 modem support
bus: mhi: host: Detect events pointing to unexpected TREs
bus: mhi: host: pci_generic: Add Foxconn T99W696 modem
bus: mhi: host: Use str_true_false() helper
bus: mhi: host: pci_generic: Add support for EM929x and set MRU to 32768 for better performance.
bus: mhi: host: Fix endianness of BHI vector table
bus: mhi: host: pci_generic: Disable runtime PM for QDU100
bus: mhi: host: pci_generic: Fix the modem name of Foxconn T99W640
dt-bindings: interconnect: qcom,msm8998-bwmon: Allow 'nonposted-mmio'
...
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
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>
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>
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>
Pull Char/Misc/IIO driver updates from Greg KH:
"Here is the "big" set of char/misc/iio and other smaller driver
subsystem updates for 6.14-rc1. Loads of different things in here this
development cycle, highlights are:
- ntsync "driver" to handle Windows locking types enabling Wine to
work much better on many workloads (i.e. games). The driver
framework was in 6.13, but now it's enabled and fully working
properly. Should make many SteamOS users happy. Even comes with
tests!
- Large IIO driver updates and bugfixes
- FPGA driver updates
- Coresight driver updates
- MHI driver updates
- PPS driver updatesa
- const bin_attribute reworking for many drivers
- binder driver updates
- smaller driver updates and fixes
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (311 commits)
ntsync: Fix reference leaks in the remaining create ioctls.
spmi: hisi-spmi-controller: Drop duplicated OF node assignment in spmi_controller_probe()
spmi: Set fwnode for spmi devices
ntsync: fix a file reference leak in drivers/misc/ntsync.c
scripts/tags.sh: Don't tag usages of DECLARE_BITMAP
dt-bindings: interconnect: qcom,msm8998-bwmon: Add SM8750 CPU BWMONs
dt-bindings: interconnect: OSM L3: Document sm8650 OSM L3 compatible
dt-bindings: interconnect: qcom-bwmon: Document QCS615 bwmon compatibles
interconnect: sm8750: Add missing const to static qcom_icc_desc
memstick: core: fix kernel-doc notation
intel_th: core: fix kernel-doc warnings
binder: log transaction code on failure
iio: dac: ad3552r-hs: clear reset status flag
iio: dac: ad3552r-common: fix ad3541/2r ranges
iio: chemical: bme680: Fix uninitialized variable in __bme680_read_raw()
misc: fastrpc: Fix copy buffer page size
misc: fastrpc: Fix registered buffer page address
misc: fastrpc: Deregister device nodes properly in error scenarios
nvmem: core: improve range check for nvmem_cell_write()
nvmem: qcom-spmi-sdam: Set size in struct nvmem_config
...
When binderfs is not enabled, the binder driver parses the kernel
config to create all binder devices. All of the new binder devices
are stored in the list binder_devices.
When binderfs is enabled, the binder driver creates new binder devices
dynamically when userspace applications call BINDER_CTL_ADD ioctl. But
the devices created in this way are not stored in the same list.
This patch fixes that.
Signed-off-by: Li Li <dualli@google.com>
Acked-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20241218212935.4162907-2-dualli@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is possible to reach the end of binder_transaction() without
having set lsmctx. As the variable value is checked there it needs
to be initialized.
Suggested-by: Kees Bakker <kees@ijzerbout.nl>
[PM: subj tweak to fit convention]
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Replace the (secctx,seclen) pointer pair with a single
lsm_context pointer to allow return of the LSM identifier
along with the context and context length. This allows
security_release_secctx() to know how to release the
context. Callers have been modified to use or save the
returned data from the new structure.
security_secid_to_secctx() and security_lsmproc_to_secctx()
will now return the length value on success instead of 0.
Cc: netdev@vger.kernel.org
Cc: audit@vger.kernel.org
Cc: netfilter-devel@vger.kernel.org
Cc: Todd Kjos <tkjos@google.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
[PM: subject tweak, kdoc fix, signedness fix from Dan Carpenter]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Add a new lsm_context data structure to hold all the information about a
"security context", including the string, its size and which LSM allocated
the string. The allocation information is necessary because LSMs have
different policies regarding the lifecycle of these strings. SELinux
allocates and destroys them on each use, whereas Smack provides a pointer
to an entry in a list that never goes away.
Update security_release_secctx() to use the lsm_context instead of a
(char *, len) pair. Change its callers to do likewise. The LSMs
supporting this hook have had comments added to remind the developer
that there is more work to be done.
The BPF security module provides all LSM hooks. While there has yet to
be a known instance of a BPF configuration that uses security contexts,
the possibility is real. In the existing implementation there is
potential for multiple frees in that case.
Cc: linux-integrity@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: audit@vger.kernel.org
Cc: netfilter-devel@vger.kernel.org
To: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: linux-nfs@vger.kernel.org
Cc: Todd Kjos <tkjos@google.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
[PM: subject tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
If a freeze notification is cleared with BC_CLEAR_FREEZE_NOTIFICATION
before calling binder_freeze_notification_done(), then it is detached
from its reference (e.g. ref->freeze) but the work remains queued in
proc->delivered_freeze. This leads to a memory leak when the process
exits as any pending entries in proc->delivered_freeze are not freed:
unreferenced object 0xffff38e8cfa36180 (size 64):
comm "binder-util", pid 655, jiffies 4294936641
hex dump (first 32 bytes):
b8 e9 9e c8 e8 38 ff ff b8 e9 9e c8 e8 38 ff ff .....8.......8..
0b 00 00 00 00 00 00 00 3c 1f 4b 00 00 00 00 00 ........<.K.....
backtrace (crc 95983b32):
[<000000000d0582cf>] kmemleak_alloc+0x34/0x40
[<000000009c99a513>] __kmalloc_cache_noprof+0x208/0x280
[<00000000313b1704>] binder_thread_write+0xdec/0x439c
[<000000000cbd33bb>] binder_ioctl+0x1b68/0x22cc
[<000000002bbedeeb>] __arm64_sys_ioctl+0x124/0x190
[<00000000b439adee>] invoke_syscall+0x6c/0x254
[<00000000173558fc>] el0_svc_common.constprop.0+0xac/0x230
[<0000000084f72311>] do_el0_svc+0x40/0x58
[<000000008b872457>] el0_svc+0x38/0x78
[<00000000ee778653>] el0t_64_sync_handler+0x120/0x12c
[<00000000a8ec61bf>] el0t_64_sync+0x190/0x194
This patch fixes the leak by ensuring that any pending entries in
proc->delivered_freeze are freed during binder_deferred_release().
Fixes: d579b04a52 ("binder: frozen notification")
Cc: stable@vger.kernel.org
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Todd Kjos <tkjos@google.com>
Link: https://lore.kernel.org/r/20240926233632.821189-8-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The BINDER_WORK_FROZEN_BINDER type is not handled in the binder_logs
entries and it shows up as "unknown work" when logged:
proc 649
context binder-test
thread 649: l 00 need_return 0 tr 0
ref 13: desc 1 node 8 s 1 w 0 d 0000000053c4c0c3
unknown work: type 10
This patch add the freeze work type and is now logged as such:
proc 637
context binder-test
thread 637: l 00 need_return 0 tr 0
ref 8: desc 1 node 3 s 1 w 0 d 00000000dc39e9c6
has frozen binder
Fixes: d579b04a52 ("binder: frozen notification")
Cc: stable@vger.kernel.org
Acked-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240926233632.821189-5-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a binder reference is cleaned up, any freeze work queued in the
associated process should also be removed. Otherwise, the reference is
freed while its ref->freeze.work is still queued in proc->work leading
to a use-after-free issue as shown by the following KASAN report:
==================================================================
BUG: KASAN: slab-use-after-free in binder_release_work+0x398/0x3d0
Read of size 8 at addr ffff31600ee91488 by task kworker/5:1/211
CPU: 5 UID: 0 PID: 211 Comm: kworker/5:1 Not tainted 6.11.0-rc7-00382-gfc6c92196396 #22
Hardware name: linux,dummy-virt (DT)
Workqueue: events binder_deferred_func
Call trace:
binder_release_work+0x398/0x3d0
binder_deferred_func+0xb60/0x109c
process_one_work+0x51c/0xbd4
worker_thread+0x608/0xee8
Allocated by task 703:
__kmalloc_cache_noprof+0x130/0x280
binder_thread_write+0xdb4/0x42a0
binder_ioctl+0x18f0/0x25ac
__arm64_sys_ioctl+0x124/0x190
invoke_syscall+0x6c/0x254
Freed by task 211:
kfree+0xc4/0x230
binder_deferred_func+0xae8/0x109c
process_one_work+0x51c/0xbd4
worker_thread+0x608/0xee8
==================================================================
This commit fixes the issue by ensuring any queued freeze work is removed
when cleaning up a binder reference.
Fixes: d579b04a52 ("binder: frozen notification")
Cc: stable@vger.kernel.org
Acked-by: Todd Kjos <tkjos@android.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20240926233632.821189-4-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In binder_add_freeze_work() we iterate over the proc->nodes with the
proc->inner_lock held. However, this lock is temporarily dropped to
acquire the node->lock first (lock nesting order). This can race with
binder_deferred_release() which removes the nodes from the proc->nodes
rbtree and adds them into binder_dead_nodes list. This leads to a broken
iteration in binder_add_freeze_work() as rb_next() will use data from
binder_dead_nodes, triggering an out-of-bounds access:
==================================================================
BUG: KASAN: global-out-of-bounds in rb_next+0xfc/0x124
Read of size 8 at addr ffffcb84285f7170 by task freeze/660
CPU: 8 UID: 0 PID: 660 Comm: freeze Not tainted 6.11.0-07343-ga727812a8d45 #18
Hardware name: linux,dummy-virt (DT)
Call trace:
rb_next+0xfc/0x124
binder_add_freeze_work+0x344/0x534
binder_ioctl+0x1e70/0x25ac
__arm64_sys_ioctl+0x124/0x190
The buggy address belongs to the variable:
binder_dead_nodes+0x10/0x40
[...]
==================================================================
This is possible because proc->nodes (rbtree) and binder_dead_nodes
(list) share entries in binder_node through a union:
struct binder_node {
[...]
union {
struct rb_node rb_node;
struct hlist_node dead_node;
};
Fix the race by checking that the proc is still alive. If not, simply
break out of the iteration.
Fixes: d579b04a52 ("binder: frozen notification")
Cc: stable@vger.kernel.org
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20240926233632.821189-3-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In binder_add_freeze_work() we iterate over the proc->nodes with the
proc->inner_lock held. However, this lock is temporarily dropped in
order to acquire the node->lock first (lock nesting order). This can
race with binder_node_release() and trigger a use-after-free:
==================================================================
BUG: KASAN: slab-use-after-free in _raw_spin_lock+0xe4/0x19c
Write of size 4 at addr ffff53c04c29dd04 by task freeze/640
CPU: 5 UID: 0 PID: 640 Comm: freeze Not tainted 6.11.0-07343-ga727812a8d45 #17
Hardware name: linux,dummy-virt (DT)
Call trace:
_raw_spin_lock+0xe4/0x19c
binder_add_freeze_work+0x148/0x478
binder_ioctl+0x1e70/0x25ac
__arm64_sys_ioctl+0x124/0x190
Allocated by task 637:
__kmalloc_cache_noprof+0x12c/0x27c
binder_new_node+0x50/0x700
binder_transaction+0x35ac/0x6f74
binder_thread_write+0xfb8/0x42a0
binder_ioctl+0x18f0/0x25ac
__arm64_sys_ioctl+0x124/0x190
Freed by task 637:
kfree+0xf0/0x330
binder_thread_read+0x1e88/0x3a68
binder_ioctl+0x16d8/0x25ac
__arm64_sys_ioctl+0x124/0x190
==================================================================
Fix the race by taking a temporary reference on the node before
releasing the proc->inner lock. This ensures the node remains alive
while in use.
Fixes: d579b04a52 ("binder: frozen notification")
Cc: stable@vger.kernel.org
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20240926233632.821189-2-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kees Cook
Linus Torvalds
Oleg Nesterov
Carlos Llamas
Thomas Weißschuh
Sunday Adelodun
Alice Ryhl
Kriish Sharma
Li Li
Tiffany Yang
Dmitry Antipov
Al Viro
Greg Kroah-Hartman
Casey Schaufler
Ba Jing