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134,602 commits

Author SHA1 Message Date
Jan Kara
f9438cb8c8 quota: Fix race of dquot_scan_active() with quota deactivation
[ Upstream commit e93ab401da ]

dquot_scan_active() can race with quota deactivation in
quota_release_workfn() like:

  CPU0 (quota_release_workfn)         CPU1 (dquot_scan_active)
  ==============================      ==============================
  spin_lock(&dq_list_lock);
  list_replace_init(
    &releasing_dquots, &rls_head);
    /* dquot X on rls_head,
       dq_count == 0,
       DQ_ACTIVE_B still set */
  spin_unlock(&dq_list_lock);
  synchronize_srcu(&dquot_srcu);
                                      spin_lock(&dq_list_lock);
                                      list_for_each_entry(dquot,
                                          &inuse_list, dq_inuse) {
                                        /* finds dquot X */
                                        dquot_active(X) -> true
                                        atomic_inc(&X->dq_count);
                                      }
                                      spin_unlock(&dq_list_lock);
  spin_lock(&dq_list_lock);
  dquot = list_first_entry(&rls_head);
  WARN_ON_ONCE(atomic_read(&dquot->dq_count));

The problem is not only a cosmetic one as under memory pressure the
caller of dquot_scan_active() can end up working on freed dquot.

Fix the problem by making sure the dquot is removed from releasing list
when we acquire a reference to it.

Fixes: 869b6ea160 ("quota: Fix slow quotaoff")
Reported-by: Sam Sun <samsun1006219@gmail.com>
Link: https://lore.kernel.org/all/CAEkJfYPTt3uP1vAYnQ5V2ZWn5O9PLhhGi5HbOcAzyP9vbXyjeg@mail.gmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:33 +02:00
Maxime Chevallier
7408cb7193 net: phy: qcom: at803x: Use the correct bit to disable extended next page
[ Upstream commit e7a62edd34 ]

As noted in the blamed commit, the AR8035 and other PHYs from this
family advertise the Extended Next Page support by default, which may be
understood by some partners as this PHY being multi-gig capable.

The fix is to disable XNP advertising, which is done by setting bit 12
of the Auto-Negotiation Advertisement Register (MII_ADVERTISE).

The blamed commit incorrectly uses MDIO_AN_CTRL1_XNP, which is bit 13 as per
802.3 : 45.2.7.1 AN control register (Register 7.0)

BIT 12 in MII_ADVERTISE is wrapped by ADVERTISE_RESV, used by some
drivers such as the aquantia one. 802.3 Clause 28 defines bit 12 as
Extended Next Page ability, at least in recent versions of the standard.

Let's add a define for it and use it in the at803x driver.

Fixes: 3c51fa5d2a ("net: phy: ar803x: disable extended next page bit")
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260410171021.1277138-1-maxime.chevallier@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:29 +02:00
Petr Pavlu
f137a21131 module: Fix freeing of charp module parameters when CONFIG_SYSFS=n
[ Upstream commit deffe1edba ]

When setting a charp module parameter, the param_set_charp() function
allocates memory to store a copy of the input value. Later, when the module
is potentially unloaded, the destroy_params() function is called to free
this allocated memory.

However, destroy_params() is available only when CONFIG_SYSFS=y, otherwise
only a dummy variant is present. In the unlikely case that the kernel is
configured with CONFIG_MODULES=y and CONFIG_SYSFS=n, this results in
a memory leak of charp values when a module is unloaded.

Fix this issue by making destroy_params() always available when
CONFIG_MODULES=y. Rename the function to module_destroy_params() to clarify
that it is intended for use by the module loader.

Fixes: e180a6b775 ("param: fix charp parameters set via sysfs")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:28 +02:00
Shyam Saini
7feee88029 kernel: globalize lookup_or_create_module_kobject()
[ Upstream commit 7c76c813cf ]

lookup_or_create_module_kobject() is marked as static and __init,
to make it global drop static keyword.
Since this function can be called from non-init code, use __modinit
instead of __init, __modinit marker will make it __init if
CONFIG_MODULES is not defined.

Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Shyam Saini <shyamsaini@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250227184930.34163-4-shyamsaini@linux.microsoft.com
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Stable-dep-of: deffe1edba ("module: Fix freeing of charp module parameters when CONFIG_SYSFS=n")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:27 +02:00
Mario Limonciello (AMD)
cd06f2ea35 firmware: dmi: Correct an indexing error in dmi.h
[ Upstream commit c064abc68e ]

The entries later in enum dmi_entry_type don't match the SMBIOS
specification¹.

The entry for type 33: `64-Bit Memory Error Information` is not present and
thus the index for all later entries is incorrect.

Add it.

Also, add missing entry types 43-46, while at it.

  ¹ Search for "System Management BIOS (SMBIOS) Reference Specification"

  [ bp: Drop the flaky SMBIOS spec URL. ]

Fixes: 93c890dbe5 ("firmware: Add DMI entry types to the headers")
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>
Link: https://patch.msgid.link/20260307141024.819807-2-superm1@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:27 +02:00
Bart Van Assche
8d146ecf5c locking: Fix rwlock support in <linux/spinlock_up.h>
[ Upstream commit 756a0e011c ]

Architecture support for rwlocks must be available whether or not
CONFIG_DEBUG_SPINLOCK has been defined. Move the definitions of the
arch_{read,write}_{lock,trylock,unlock}() macros such that these become
visbile if CONFIG_DEBUG_SPINLOCK=n.

This patch prepares for converting do_raw_{read,write}_trylock() into
inline functions. Without this patch that conversion triggers a build
failure for UP architectures, e.g. arm-ep93xx. I used the following
kernel configuration to build the kernel for that architecture:

	CONFIG_ARCH_MULTIPLATFORM=y
	CONFIG_ARCH_MULTI_V7=n
	CONFIG_ATAGS=y
	CONFIG_MMU=y
	CONFIG_ARCH_MULTI_V4T=y
	CONFIG_CPU_LITTLE_ENDIAN=y
	CONFIG_ARCH_EP93XX=y

Fixes: fb1c8f93d8 ("[PATCH] spinlock consolidation")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260313171510.230998-2-bvanassche@acm.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:27 +02:00
Miklos Szeredi
4a7611ad65 fanotify: fix false positive on permission events
commit 7746e3bd4c upstream.

fsnotify_get_mark_safe() may return false for a mark on an unrelated group,
which results in bypassing the permission check.

Fix by skipping over detached marks that are not in the current group.

CC: stable@vger.kernel.org
Fixes: abc77577a6 ("fsnotify: Provide framework for dropping SRCU lock in ->handle_event")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Link: https://patch.msgid.link/20260410144950.156160-1-mszeredi@redhat.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:21 +02:00
Rajat Gupta
5931f5651e fbdev: udlfb: add vm_ops to dlfb_ops_mmap to prevent use-after-free
commit 8de779dc40 upstream.

dlfb_ops_mmap() uses remap_pfn_range() to map vmalloc framebuffer pages
to userspace but sets no vm_ops on the VMA. This means the kernel cannot
track active mmaps. When dlfb_realloc_framebuffer() replaces the backing
buffer via FBIOPUT_VSCREENINFO, existing mmap PTEs are not invalidated.
On USB disconnect, dlfb_ops_destroy() calls vfree() on the old pages
while userspace PTEs still reference them, resulting in a use-after-free:
the process retains read/write access to freed kernel pages.

Add vm_operations_struct with open/close callbacks that maintain an
atomic mmap_count on struct dlfb_data. In dlfb_realloc_framebuffer(),
check mmap_count and return -EBUSY if the buffer is currently mapped,
preventing buffer replacement while userspace holds stale PTEs.

Tested with PoC using dummy_hcd + raw_gadget USB device emulation.

Signed-off-by: Rajat Gupta <rajgupt@qti.qualcomm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:19 +02:00
Douglas Anderson
e1f4825d2f driver core: Add kernel-doc for DEV_FLAG_COUNT enum value
commit 5b48431150 upstream.

Even though nobody should use this value (except when declaring the
"flags" bitmap), kernel-doc still gets upset that it's not documented.
It reports:

  WARNING: ../include/linux/device.h:519
  Enum value 'DEV_FLAG_COUNT' not described in enum 'struct_device_flags'

Add the description of DEV_FLAG_COUNT.

Fixes: a2225b6e83 ("driver core: Don't let a device probe until it's ready")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Closes: https://lore.kernel.org/f318cd43-81fd-48b9-abf7-92af85f12f91@infradead.org
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://patch.msgid.link/20260413195910.1.I23aca74fe2d3636a47df196a80920fecb2643220@changeid
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:18 +02:00
Arnd Bergmann
5db32746ff tpm: avoid -Wunused-but-set-variable
commit 6f1d4d2ecf upstream.

Outside of the EFI tpm code, the TPM_MEMREMAP()/TPM_MEMUNMAP functions are
defined as trivial macros, leading to the mapping_size variable ending
up unused:

In file included from drivers/char/tpm/tpm-sysfs.c:16:
In file included from drivers/char/tpm/tpm.h:28:
include/linux/tpm_eventlog.h:167:6: error: variable 'mapping_size' set but not used [-Werror,-Wunused-but-set-variable]
  167 |         int mapping_size;

Turn the stubs into inline functions to avoid this warning.

Cc: stable@vger.kernel.org # v5.3+
Fixes: c46f340569 ("tpm: Reserve the TPM final events table")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:16 +02:00
Douglas Anderson
34fdc6c621 driver core: Don't let a device probe until it's ready
[ Upstream commit a2225b6e83 ]

The moment we link a "struct device" into the list of devices for the
bus, it's possible probe can happen. This is because another thread
can load the driver at any time and that can cause the device to
probe. This has been seen in practice with a stack crawl that looks
like this [1]:

  really_probe()
  __driver_probe_device()
  driver_probe_device()
  __driver_attach()
  bus_for_each_dev()
  driver_attach()
  bus_add_driver()
  driver_register()
  __platform_driver_register()
  init_module() [some module]
  do_one_initcall()
  do_init_module()
  load_module()
  __arm64_sys_finit_module()
  invoke_syscall()

As a result of the above, it was seen that device_links_driver_bound()
could be called for the device before "dev->fwnode->dev" was
assigned. This prevented __fw_devlink_pickup_dangling_consumers() from
being called which meant that other devices waiting on our driver's
sub-nodes were stuck deferring forever.

It's believed that this problem is showing up suddenly for two
reasons:
1. Android has recently (last ~1 year) implemented an optimization to
   the order it loads modules [2]. When devices opt-in to this faster
   loading, modules are loaded one-after-the-other very quickly. This
   is unlike how other distributions do it. The reproduction of this
   problem has only been seen on devices that opt-in to Android's
   "parallel module loading".
2. Android devices typically opt-in to fw_devlink, and the most
   noticeable issue is the NULL "dev->fwnode->dev" in
   device_links_driver_bound(). fw_devlink is somewhat new code and
   also not in use by all Linux devices.

Even though the specific symptom where "dev->fwnode->dev" wasn't
assigned could be fixed by moving that assignment higher in
device_add(), other parts of device_add() (like the call to
device_pm_add()) are also important to run before probe. Only moving
the "dev->fwnode->dev" assignment would likely fix the current
symptoms but lead to difficult-to-debug problems in the future.

Fix the problem by preventing probe until device_add() has run far
enough that the device is ready to probe. If somehow we end up trying
to probe before we're allowed, __driver_probe_device() will return
-EPROBE_DEFER which will make certain the device is noticed.

In the race condition that was seen with Android's faster module
loading, we will temporarily add the device to the deferred list and
then take it off immediately when device_add() probes the device.

Instead of adding another flag to the bitfields already in "struct
device", instead add a new "flags" field and use that. This allows us
to freely change the bit from different thread without worrying about
corrupting nearby bits (and means threads changing other bit won't
corrupt us).

[1] Captured on a machine running a downstream 6.6 kernel
[2] https://cs.android.com/android/platform/superproject/main/+/main:system/core/libmodprobe/libmodprobe.cpp?q=LoadModulesParallel

Cc: stable@vger.kernel.org
Fixes: 2023c610dc ("Driver core: add new device to bus's list before probing")
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patch.msgid.link/20260406162231.v5.1.Id750b0fbcc94f23ed04b7aecabcead688d0d8c17@changeid
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:14 +02:00
Herbert Xu
be66b85d18 padata: Remove comment for reorder_work
[ Upstream commit 82a0302e71 ]

Remove comment for reorder_work which no longer exists.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 71203f68c7 ("padata: Fix pd UAF once and for all")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Bin Lan <lanbincn@139.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:14 +02:00
Herbert Xu
73f132e608 padata: Fix pd UAF once and for all
[ Upstream commit 71203f68c7 ]

There is a race condition/UAF in padata_reorder that goes back
to the initial commit.  A reference count is taken at the start
of the process in padata_do_parallel, and released at the end in
padata_serial_worker.

This reference count is (and only is) required for padata_replace
to function correctly.  If padata_replace is never called then
there is no issue.

In the function padata_reorder which serves as the core of padata,
as soon as padata is added to queue->serial.list, and the associated
spin lock released, that padata may be processed and the reference
count on pd would go away.

Fix this by getting the next padata before the squeue->serial lock
is released.

In order to make this possible, simplify padata_reorder by only
calling it once the next padata arrives.

Fixes: 16295bec63 ("padata: Generic parallelization/serialization interface")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[ Adjust context of padata_find_next(). Replace
cpumask_next_wrap(cpu, pd->cpumask.pcpu) with
cpumask_next_wrap(cpu, pd->cpumask.pcpu, -1, false) in padata_reorder() in
v5.15 according to dc5bb9b769 ("cpumask: deprecate cpumask_next_wrap()") and
f954a2d376 ("padata: switch padata_find_next() to using cpumask_next_wrap()")
. ]
Signed-off-by: Bin Lan <lanbincn@139.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:14 +02:00
Douglas Anderson
17f1675a47 device property: Make modifications of fwnode "flags" thread safe
commit f72e77c33e upstream.

In various places in the kernel, we modify the fwnode "flags" member
by doing either:
  fwnode->flags |= SOME_FLAG;
  fwnode->flags &= ~SOME_FLAG;

This type of modification is not thread-safe. If two threads are both
mucking with the flags at the same time then one can clobber the
other.

While flags are often modified while under the "fwnode_link_lock",
this is not universally true.

Create some accessor functions for setting, clearing, and testing the
FWNODE flags and move all users to these accessor functions. New
accessor functions use set_bit() and clear_bit(), which are
thread-safe.

Cc: stable@vger.kernel.org
Fixes: c2c724c868 ("driver core: Add fw_devlink_parse_fwtree()")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reviewed-by: Saravana Kannan <saravanak@kernel.org>
Link: https://patch.msgid.link/20260317090112.v2.1.I0a4d03104ecd5103df3d76f66c8d21b1d15a2e38@changeid
[ Fix fwnode_clear_flag() argument alignment, restore dropped blank
  line in fwnode_dev_initialized(), and remove unnecessary parentheses
  around fwnode_test_flag() calls. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:13 +02:00
Michal Pecio
1d93dae6cf usb: xhci: Make usb_host_endpoint.hcpriv survive endpoint_disable()
commit 25e531b422 upstream.

xHCI hardware maintains its endpoint state between add_endpoint()
and drop_endpoint() calls followed by successful check_bandwidth().
So does the driver.

Core may call endpoint_disable() during xHCI endpoint life, so don't
clear host_ep->hcpriv then, because this breaks endpoint_reset().

If a driver calls usb_set_interface(), submits URBs which make host
sequence state non-zero and calls usb_clear_halt(), the device clears
its sequence state but xhci_endpoint_reset() bails out. The next URB
malfunctions: USB2 loses one packet, USB3 gets Transaction Error or
may not complete at all on some (buggy?) HCs from ASMedia and AMD.
This is triggered by uvcvideo on bulk video devices.

The code was copied from ehci_endpoint_disable() but it isn't needed
here - hcpriv should only be NULL on emulated root hub endpoints.
It might prevent resetting and inadvertently enabling a disabled and
dropped endpoint, but core shouldn't try to reset dropped endpoints.

Document xhci requirements regarding hcpriv. They are currently met.

Fixes: 18b74067ac ("xhci: Fix use-after-free regression in xhci clear hub TT implementation")
Cc: stable@vger.kernel.org
Signed-off-by: Michal Pecio <michal.pecio@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://patch.msgid.link/20260402131342.2628648-26-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:13 +02:00
Miquel Sabaté Solà
2b846344b1 cpufreq: Avoid a bad reference count on CPU node
[ Upstream commit c0f02536ff ]

In the parse_perf_domain function, if the call to
of_parse_phandle_with_args returns an error, then the reference to the
CPU device node that was acquired at the start of the function would not
be properly decremented.

Address this by declaring the variable with the __free(device_node)
cleanup attribute.

Signed-off-by: Miquel Sabaté Solà <mikisabate@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/20240917134246.584026-1-mikisabate@gmail.com
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[ Minor context conflict resolved. ]
Signed-off-by: Bin Lan <lanbincn@139.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:11 +02:00
David Howells
c198628f3f rxrpc: Fix recvmsg() unconditional requeue
[ Upstream commit 2c28769a51 ]

If rxrpc_recvmsg() fails because MSG_DONTWAIT was specified but the call
at the front of the recvmsg queue already has its mutex locked, it
requeues the call - whether or not the call is already queued.  The call
may be on the queue because MSG_PEEK was also passed and so the call was
not dequeued or because the I/O thread requeued it.

The unconditional requeue may then corrupt the recvmsg queue, leading to
things like UAFs or refcount underruns.

Fix this by only requeuing the call if it isn't already on the queue -
and moving it to the front if it is already queued.  If we don't queue
it, we have to put the ref we obtained by dequeuing it.

Also, MSG_PEEK doesn't dequeue the call so shouldn't call
rxrpc_notify_socket() for the call if we didn't use up all the data on
the queue, so fix that also.

Fixes: 540b1c48c3 ("rxrpc: Fix deadlock between call creation and sendmsg/recvmsg")
Reported-by: Faith <faith@zellic.io>
Reported-by: Pumpkin Chang <pumpkin@devco.re>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cc: stable@vger.kernel.org
[Adapted to 5.15: use write_lock_bh/write_unlock_bh, trace_rxrpc_call
 directly for see-call tracing, 5.15 trace enum naming convention, and
 added entries to both plain enum and EM() macro list.]
Signed-off-by: Jay Wang <wanjay@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:11 +02:00
Kuniyuki Iwashima
90dee0a0ff Bluetooth: hci_core: Fix use-after-free in vhci_flush()
[ Upstream commit 1d6123102e ]

syzbot reported use-after-free in vhci_flush() without repro. [0]

>From the splat, a thread close()d a vhci file descriptor while
its device was being used by iotcl() on another thread.

Once the last fd refcnt is released, vhci_release() calls
hci_unregister_dev(), hci_free_dev(), and kfree() for struct
vhci_data, which is set to hci_dev->dev->driver_data.

The problem is that there is no synchronisation after unlinking
hdev from hci_dev_list in hci_unregister_dev().  There might be
another thread still accessing the hdev which was fetched before
the unlink operation.

We can use SRCU for such synchronisation.

Let's run hci_dev_reset() under SRCU and wait for its completion
in hci_unregister_dev().

Another option would be to restore hci_dev->destruct(), which was
removed in commit 587ae086f6 ("Bluetooth: Remove unused
hci-destruct cb").  However, this would not be a good solution, as
we should not run hci_unregister_dev() while there are in-flight
ioctl() requests, which could lead to another data-race KCSAN splat.

Note that other drivers seem to have the same problem, for exmaple,
virtbt_remove().

[0]:
BUG: KASAN: slab-use-after-free in skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline]
BUG: KASAN: slab-use-after-free in skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937
Read of size 8 at addr ffff88807cb8d858 by task syz.1.219/6718

CPU: 1 UID: 0 PID: 6718 Comm: syz.1.219 Not tainted 6.16.0-rc1-syzkaller-00196-g08207f42d3ff #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xd2/0x2b0 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline]
 skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937
 skb_queue_purge include/linux/skbuff.h:3368 [inline]
 vhci_flush+0x44/0x50 drivers/bluetooth/hci_vhci.c:69
 hci_dev_do_reset net/bluetooth/hci_core.c:552 [inline]
 hci_dev_reset+0x420/0x5c0 net/bluetooth/hci_core.c:592
 sock_do_ioctl+0xd9/0x300 net/socket.c:1190
 sock_ioctl+0x576/0x790 net/socket.c:1311
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcf5b98e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcf5c7b9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcf5bbb6160 RCX: 00007fcf5b98e929
RDX: 0000000000000000 RSI: 00000000400448cb RDI: 0000000000000009
RBP: 00007fcf5ba10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcf5bbb6160 R15: 00007ffd6353d528
 </TASK>

Allocated by task 6535:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 vhci_open+0x57/0x360 drivers/bluetooth/hci_vhci.c:635
 misc_open+0x2bc/0x330 drivers/char/misc.c:161
 chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414
 do_dentry_open+0xdf0/0x1970 fs/open.c:964
 vfs_open+0x3b/0x340 fs/open.c:1094
 do_open fs/namei.c:3887 [inline]
 path_openat+0x2ee5/0x3830 fs/namei.c:4046
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6535:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kfree+0x18e/0x440 mm/slub.c:4842
 vhci_release+0xbc/0xd0 drivers/bluetooth/hci_vhci.c:671
 __fput+0x44c/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6ad/0x22e0 kernel/exit.c:955
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104
 __do_sys_exit_group kernel/exit.c:1115 [inline]
 __se_sys_exit_group kernel/exit.c:1113 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1113
 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807cb8d800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 88 bytes inside of
 freed 1024-byte region [ffff88807cb8d800, ffff88807cb8dc00)

Fixes: bf18c7118c ("Bluetooth: vhci: Free driver_data on file release")
Reported-by: syzbot+2faa4825e556199361f9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=f62d64848fc4c7c30cd6
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
[ Minor context conflict resolved. ]
Signed-off-by: Ruohan Lan <ruohanlan@aliyun.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:09 +02:00
Oleg Nesterov
d9a60636fe x86/uprobes: Fix XOL allocation failure for 32-bit tasks
[ Upstream commit d55c571e43 ]

This script

	#!/usr/bin/bash

	echo 0 > /proc/sys/kernel/randomize_va_space

	echo 'void main(void) {}' > TEST.c

	# -fcf-protection to ensure that the 1st endbr32 insn can't be emulated
	gcc -m32 -fcf-protection=branch TEST.c -o test

	bpftrace -e 'uprobe:./test:main {}' -c ./test

"hangs", the probed ./test task enters an endless loop.

The problem is that with randomize_va_space == 0
get_unmapped_area(TASK_SIZE - PAGE_SIZE) called by xol_add_vma() can not
just return the "addr == TASK_SIZE - PAGE_SIZE" hint, this addr is used
by the stack vma.

arch_get_unmapped_area_topdown() doesn't take TIF_ADDR32 into account and
in_32bit_syscall() is false, this leads to info.high_limit > TASK_SIZE.
vm_unmapped_area() happily returns the high address > TASK_SIZE and then
get_unmapped_area() returns -ENOMEM after the "if (addr > TASK_SIZE - len)"
check.

handle_swbp() doesn't report this failure (probably it should) and silently
restarts the probed insn. Endless loop.

I think that the right fix should change the x86 get_unmapped_area() paths
to rely on TIF_ADDR32 rather than in_32bit_syscall(). Note also that if
CONFIG_X86_X32_ABI=y, in_x32_syscall() falsely returns true in this case
because ->orig_ax = -1.

But we need a simple fix for -stable, so this patch just sets TS_COMPAT if
the probed task is 32-bit to make in_ia32_syscall() true.

Fixes: 1b028f784e ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()")
Reported-by: Paulo Andrade <pandrade@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/aV5uldEvV7pb4RA8@redhat.com/
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/aWO7Fdxn39piQnxu@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:09 +02:00
Eric Dumazet
3905d3140c net: add skb_header_pointer_careful() helper
[ Upstream commit 13e00fdc92 ]

This variant of skb_header_pointer() should be used in contexts
where @offset argument is user-controlled and could be negative.

Negative offsets are supported, as long as the zone starts
between skb->head and skb->data.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260128141539.3404400-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ Adjust context ]
Signed-off-by: Bin Lan <lanbincn@139.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:09 +02:00
Felix Fietkau
5ef8ca1c16 wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure
[ Upstream commit d5ad6ab61c ]

ieee80211_tx_prepare_skb() has three error paths, but only two of them
free the skb. The first error path (ieee80211_tx_prepare() returning
TX_DROP) does not free it, while invoke_tx_handlers() failure and the
fragmentation check both do.

Add kfree_skb() to the first error path so all three are consistent,
and remove the now-redundant frees in callers (ath9k, mt76,
mac80211_hwsim) to avoid double-free.

Document the skb ownership guarantee in the function's kdoc.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://patch.msgid.link/20260314065455.2462900-1-nbd@nbd.name
Fixes: 06be6b149f ("mac80211: add ieee80211_tx_prepare_skb() helper function")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[ Exclude changes to drivers/net/wireless/mediatek/mt76/scan.c as this file is first
 introduced by commit 31083e38548f("wifi: mt76: add code for emulating hardware scanning")
 after linux-6.14.]
Signed-off-by: Li hongliang <1468888505@139.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:07 +02:00
Sean Christopherson
4569c66dd9 KVM: x86: Use scratch field in MMIO fragment to hold small write values
commit 0b16e69d17 upstream.

When exiting to userspace to service an emulated MMIO write, copy the
to-be-written value to a scratch field in the MMIO fragment if the size
of the data payload is 8 bytes or less, i.e. can fit in a single chunk,
instead of pointing the fragment directly at the source value.

This fixes a class of use-after-free bugs that occur when the emulator
initiates a write using an on-stack, local variable as the source, the
write splits a page boundary, *and* both pages are MMIO pages.  Because
KVM's ABI only allows for physically contiguous MMIO requests, accesses
that split MMIO pages are separated into two fragments, and are sent to
userspace one at a time.  When KVM attempts to complete userspace MMIO in
response to KVM_RUN after the first fragment, KVM will detect the second
fragment and generate a second userspace exit, and reference the on-stack
variable.

The issue is most visible if the second KVM_RUN is performed by a separate
task, in which case the stack of the initiating task can show up as truly
freed data.

  ==================================================================
  BUG: KASAN: use-after-free in complete_emulated_mmio+0x305/0x420
  Read of size 1 at addr ffff888009c378d1 by task syz-executor417/984

  CPU: 1 PID: 984 Comm: syz-executor417 Not tainted 5.10.0-182.0.0.95.h2627.eulerosv2r13.x86_64 #3
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 Call Trace:
  dump_stack+0xbe/0xfd
  print_address_description.constprop.0+0x19/0x170
  __kasan_report.cold+0x6c/0x84
  kasan_report+0x3a/0x50
  check_memory_region+0xfd/0x1f0
  memcpy+0x20/0x60
  complete_emulated_mmio+0x305/0x420
  kvm_arch_vcpu_ioctl_run+0x63f/0x6d0
  kvm_vcpu_ioctl+0x413/0xb20
  __se_sys_ioctl+0x111/0x160
  do_syscall_64+0x30/0x40
  entry_SYSCALL_64_after_hwframe+0x67/0xd1
  RIP: 0033:0x42477d
  Code: <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
  RSP: 002b:00007faa8e6890e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 00000000004d7338 RCX: 000000000042477d
  RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
  RBP: 00000000004d7330 R08: 00007fff28d546df R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004d733c
  R13: 0000000000000000 R14: 000000000040a200 R15: 00007fff28d54720

  The buggy address belongs to the page:
  page:0000000029f6a428 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9c37
  flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff)
  raw: 000fffffc0000000 0000000000000000 ffffea0000270dc8 0000000000000000
  raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected

  Memory state around the buggy address:
  ffff888009c37780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff888009c37800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  >ffff888009c37880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                   ^
  ffff888009c37900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff888009c37980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ==================================================================

The bug can also be reproduced with a targeted KVM-Unit-Test by hacking
KVM to fill a large on-stack variable in complete_emulated_mmio(), i.e. by
overwrite the data value with garbage.

Limit the use of the scratch fields to 8-byte or smaller accesses, and to
just writes, as larger accesses and reads are not affected thanks to
implementation details in the emulator, but add a sanity check to ensure
those details don't change in the future.  Specifically, KVM never uses
on-stack variables for accesses larger that 8 bytes, e.g. uses an operand
in the emulator context, and *all* reads are buffered through the mem_read
cache.

Note!  Using the scratch field for reads is not only unnecessary, it's
also extremely difficult to handle correctly.  As above, KVM buffers all
reads through the mem_read cache, and heavily relies on that behavior when
re-emulating the instruction after a userspace MMIO read exit.  If a read
splits a page, the first page is NOT an MMIO page, and the second page IS
an MMIO page, then the MMIO fragment needs to point at _just_ the second
chunk of the destination, i.e. its position in the mem_read cache.  Taking
the "obvious" approach of copying the fragment value into the destination
when re-emulating the instruction would clobber the first chunk of the
destination, i.e. would clobber the data that was read from guest memory.

Fixes: f78146b0f9 ("KVM: Fix page-crossing MMIO")
Suggested-by: Yashu Zhang <zhangjiaji1@huawei.com>
Reported-by: Yashu Zhang <zhangjiaji1@huawei.com>
Closes: https://lore.kernel.org/all/369eaaa2b3c1425c85e8477066391bc7@huawei.com
Cc: stable@vger.kernel.org
Tested-by: Tom Lendacky <thomas.lendacky@gmail.com>
Tested-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Link: https://patch.msgid.link/20260225012049.920665-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-01 17:35:06 +02:00
Pablo Neira Ayuso
eb7bf413e5 nf_tables: nft_dynset: fix possible stateful expression memleak in error path
[ Upstream commit 0548a13b5a ]

If cloning the second stateful expression in the element via GFP_ATOMIC
fails, then the first stateful expression remains in place without being
released.

   unreferenced object (percpu) 0x607b97e9cab8 (size 16):
     comm "softirq", pid 0, jiffies 4294931867
     hex dump (first 16 bytes on cpu 3):
       00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
     backtrace (crc 0):
       pcpu_alloc_noprof+0x453/0xd80
       nft_counter_clone+0x9c/0x190 [nf_tables]
       nft_expr_clone+0x8f/0x1b0 [nf_tables]
       nft_dynset_new+0x2cb/0x5f0 [nf_tables]
       nft_rhash_update+0x236/0x11c0 [nf_tables]
       nft_dynset_eval+0x11f/0x670 [nf_tables]
       nft_do_chain+0x253/0x1700 [nf_tables]
       nft_do_chain_ipv4+0x18d/0x270 [nf_tables]
       nf_hook_slow+0xaa/0x1e0
       ip_local_deliver+0x209/0x330

Fixes: 563125a73a ("netfilter: nftables: generalize set extension to support for several expressions")
Reported-by: Gurpreet Shergill <giki.shergill@proton.me>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
[ Minor conflict resolved. ]
Signed-off-by: Li hongliang <1468888505@139.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:05 +02:00
Krzysztof Kozlowski
533396c766 fsl-mc: Use driver_set_override() instead of open-coding
[ Upstream commit 5688f212e9 ]

Use a helper to set driver_override to reduce the amount of duplicated
code.  Make the driver_override field const char, because it is not
modified by the core and it matches other subsystems.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220419113435.246203-4-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:05 +02:00
Goldwyn Rodrigues
520e8b4bcf btrfs: tracepoints: get correct superblock from dentry in event btrfs_sync_file()
[ Upstream commit a85b46db14 ]

If overlay is used on top of btrfs, dentry->d_sb translates to overlay's
super block and fsid assignment will lead to a crash.

Use file_inode(file)->i_sb to always get btrfs_sb.

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-06-01 17:35:00 +02:00
Linus Torvalds
15b828a46f ptrace: slightly saner 'get_dumpable()' logic
commit 31e62c2ebb upstream.

The 'dumpability' of a task is fundamentally about the memory image of
the task - the concept comes from whether it can core dump or not - and
makes no sense when you don't have an associated mm.

And almost all users do in fact use it only for the case where the task
has a mm pointer.

But we have one odd special case: ptrace_may_access() uses 'dumpable' to
check various other things entirely independently of the MM (typically
explicitly using flags like PTRACE_MODE_READ_FSCREDS).  Including for
threads that no longer have a VM (and maybe never did, like most kernel
threads).

It's not what this flag was designed for, but it is what it is.

The ptrace code does check that the uid/gid matches, so you do have to
be uid-0 to see kernel thread details, but this means that the
traditional "drop capabilities" model doesn't make any difference for
this all.

Make it all make a *bit* more sense by saying that if you don't have a
MM pointer, we'll use a cached "last dumpability" flag if the thread
ever had a MM (it will be zero for kernel threads since it is never
set), and require a proper CAP_SYS_PTRACE capability to override.

Reported-by: Qualys Security Advisory <qsa@qualys.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <kees@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-15 14:48:45 +02:00
Herbert Xu
19d43105a9 crypto: algif_aead - Revert to operating out-of-place
commit a664bf3d60 upstream.

This mostly reverts commit 72548b093e except for the copying of
the associated data.

There is no benefit in operating in-place in algif_aead since the
source and destination come from different mappings.  Get rid of
all the complexity added for in-place operation and just copy the
AD directly.

Fixes: 72548b093e ("crypto: algif_aead - copy AAD from src to dst")
Reported-by: Taeyang Lee <0wn@theori.io>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-30 11:24:38 +02:00
Eric Biggers
36435a56cd crypto: scatterwalk - Backport memcpy_sglist()
This backports the current implementation of memcpy_sglist() from
upstream commit 4dffc9bbff.

This function was rewritten twice.  The earlier implementations had many
prerequisite commits, while the latest implementation is standalone.
It's much easier to just backport the latest code directly.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-30 11:24:37 +02:00
Jinjiang Tu
f1acf5887c mm/huge_memory: fix folio isn't locked in softleaf_to_folio()
[ Upstream commit 4c5e7f0fcd ]

On arm64 server, we found folio that get from migration entry isn't locked
in softleaf_to_folio().  This issue triggers when mTHP splitting and
zap_nonpresent_ptes() races, and the root cause is lack of memory barrier
in softleaf_to_folio().  The race is as follows:

	CPU0                                             CPU1

deferred_split_scan()                              zap_nonpresent_ptes()
  lock folio
  split_folio()
    unmap_folio()
      change ptes to migration entries
    __split_folio_to_order()                         softleaf_to_folio()
      set flags(including PG_locked) for tail pages    folio = pfn_folio(softleaf_to_pfn(entry))
      smp_wmb()                                        VM_WARN_ON_ONCE(!folio_test_locked(folio))
      prep_compound_page() for tail pages

In __split_folio_to_order(), smp_wmb() guarantees page flags of tail pages
are visible before the tail page becomes non-compound.  smp_wmb() should
be paired with smp_rmb() in softleaf_to_folio(), which is missed.  As a
result, if zap_nonpresent_ptes() accesses migration entry that stores tail
pfn, softleaf_to_folio() may see the updated compound_head of tail page
before page->flags.

This issue will trigger VM_WARN_ON_ONCE() in pfn_swap_entry_folio()
because of the race between folio split and zap_nonpresent_ptes()
leading to a folio incorrectly undergoing modification without a folio
lock being held.

This is a BUG_ON() before commit 93976a2034 ("mm: eliminate further
swapops predicates"), which in merged in v6.19-rc1.

To fix it, add missing smp_rmb() if the softleaf entry is migration entry
in softleaf_to_folio() and softleaf_to_page().

[tujinjiang@huawei.com: update function name and comments]
  Link: https://lkml.kernel.org/r/20260321075214.3305564-1-tujinjiang@huawei.com
Link: https://lkml.kernel.org/r/20260319012541.4158561-1-tujinjiang@huawei.com
Fixes: e9b61f1985 ("thp: reintroduce split_huge_page()")
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Barry Song <baohua@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ adapted fix from leafops.h softleaf_to_page()/softleaf_to_folio() ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-18 10:33:38 +02:00
Tuan Do
c581e5c8f2 netfilter: nft_ct: fix use-after-free in timeout object destroy
commit f8dca15a1b upstream.

nft_ct_timeout_obj_destroy() frees the timeout object with kfree()
immediately after nf_ct_untimeout(), without waiting for an RCU grace
period. Concurrent packet processing on other CPUs may still hold
RCU-protected references to the timeout object obtained via
rcu_dereference() in nf_ct_timeout_data().

Add an rcu_head to struct nf_ct_timeout and use kfree_rcu() to defer
freeing until after an RCU grace period, matching the approach already
used in nfnetlink_cttimeout.c.

KASAN report:
 BUG: KASAN: slab-use-after-free in nf_conntrack_tcp_packet+0x1381/0x29d0
 Read of size 4 at addr ffff8881035fe19c by task exploit/80

 Call Trace:
  nf_conntrack_tcp_packet+0x1381/0x29d0
  nf_conntrack_in+0x612/0x8b0
  nf_hook_slow+0x70/0x100
  __ip_local_out+0x1b2/0x210
  tcp_sendmsg_locked+0x722/0x1580
  __sys_sendto+0x2d8/0x320

 Allocated by task 75:
  nft_ct_timeout_obj_init+0xf6/0x290
  nft_obj_init+0x107/0x1b0
  nf_tables_newobj+0x680/0x9c0
  nfnetlink_rcv_batch+0xc29/0xe00

 Freed by task 26:
  nft_obj_destroy+0x3f/0xa0
  nf_tables_trans_destroy_work+0x51c/0x5c0
  process_one_work+0x2c4/0x5a0

Fixes: 7e0b2b57f0 ("netfilter: nft_ct: add ct timeout support")
Cc: stable@vger.kernel.org
Signed-off-by: Tuan Do <tuan@calif.io>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-18 10:33:36 +02:00
Quanmin Yan
39c2c1a277 fbcon: Set fb_display[i]->mode to NULL when the mode is released
[ Upstream commit a1f3058930 ]

Recently, we discovered the following issue through syzkaller:

BUG: KASAN: slab-use-after-free in fb_mode_is_equal+0x285/0x2f0
Read of size 4 at addr ff11000001b3c69c by task syz.xxx
...
Call Trace:
 <TASK>
 dump_stack_lvl+0xab/0xe0
 print_address_description.constprop.0+0x2c/0x390
 print_report+0xb9/0x280
 kasan_report+0xb8/0xf0
 fb_mode_is_equal+0x285/0x2f0
 fbcon_mode_deleted+0x129/0x180
 fb_set_var+0xe7f/0x11d0
 do_fb_ioctl+0x6a0/0x750
 fb_ioctl+0xe0/0x140
 __x64_sys_ioctl+0x193/0x210
 do_syscall_64+0x5f/0x9c0
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Based on experimentation and analysis, during framebuffer unregistration,
only the memory of fb_info->modelist is freed, without setting the
corresponding fb_display[i]->mode to NULL for the freed modes. This leads
to UAF issues during subsequent accesses. Here's an example of reproduction
steps:
1. With /dev/fb0 already registered in the system, load a kernel module
   to register a new device /dev/fb1;
2. Set fb1's mode to the global fb_display[] array (via FBIOPUT_CON2FBMAP);
3. Switch console from fb to VGA (to allow normal rmmod of the ko);
4. Unload the kernel module, at this point fb1's modelist is freed, leaving
   a wild pointer in fb_display[];
5. Trigger the bug via system calls through fb0 attempting to delete a mode
   from fb0.

Add a check in do_unregister_framebuffer(): if the mode to be freed exists
in fb_display[], set the corresponding mode pointer to NULL.

[ The context change is due to the commit 2c0c19b681
("fbdev: fbmem: Fix double free of 'fb_info->pixmap.addr'") in v5.16
which is irrelevant to the logic of this patch. ]

Signed-off-by: Quanmin Yan <yanquanmin1@huawei.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Johnny Hao <johnny_haocn@sina.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:35 +02:00
Florian Westphal
b48f844536 netfilter: ipset: use nla_strcmp for IPSET_ATTR_NAME attr
[ Upstream commit b7e8590987 ]

IPSET_ATTR_NAME and IPSET_ATTR_NAMEREF are of NLA_STRING type, they
cannot be treated like a c-string.

They either have to be switched to NLA_NUL_STRING, or the compare
operations need to use the nla functions.

Fixes: f830837f0e ("netfilter: ipset: list:set set type support")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:30 +02:00
Hans de Goede
870f9c647d ACPICA: Allow address_space_handler Install and _REG execution as 2 separate steps
[ Upstream commit 54c516aeb8 ]

ACPI-2.0 says that the EC op_region handler must be available immediately
(like the standard default op_region handlers):

Quoting from the ACPI spec version 6.3: "6.5.4 _REG (Region) ...
2. OSPM must make Embedded Controller operation regions, accessed via
the Embedded Controllers described in ECDT, available before executing
any control method. These operation regions may become inaccessible
after OSPM runs _REG(EmbeddedControl, 0)."

So the OS must probe the ECDT described EC and install the OpRegion handler
before calling acpi_enable_subsystem() and acpi_initialize_objects().

This is a problem because calling acpi_install_address_space_handler()
does not just install the op_region handler, it also runs the EC's _REG
method. This _REG method may rely on initialization done by the _INI
methods of one of the PCI / _SB root devices.

For the other early/default op_region handlers the op_region handler
install and the _REG execution is split into 2 separate steps:
1. acpi_ev_install_region_handlers(), called early from acpi_load_tables()
2. acpi_ev_initialize_op_regions(), called from acpi_initialize_objects()

To fix the EC op_region issue, add 2 bew functions:
1. acpi_install_address_space_handler_no_reg()
2. acpi_execute_reg_methods()
to allow doing things in 2 steps for other op_region handlers,
like the EC handler, too.

Note that the comment describing acpi_ev_install_region_handlers() even has
an alinea describing this problem. Using the new methods allows users
to avoid this problem.

Link: https://github.com/acpica/acpica/pull/786
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214899
Reported-and-tested-by: Johannes Penßel <johannespenssel@posteo.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: f6484cadbc ("ACPI: EC: clean up handlers on probe failure in acpi_ec_setup()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:26 +02:00
Hans de Goede
01237527e4 ACPICA: include/acpi/acpixf.h: Fix indentation
[ Upstream commit 7a9d74e7e4 ]

A bunch of the functions declared in include/acpi/acpixf.h have their
name aligned a space after the '(' of e.g. the
`ACPI_EXTERNAL_RETURN_STATUS(acpi_status` line above rather then being
directly aligned after the '('.

This breaks applying patches generated from the ACPICA upstream git,
remove the extra space before the function-names and all the arguments
to fix this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: f6484cadbc ("ACPI: EC: clean up handlers on probe failure in acpi_ec_setup()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:26 +02:00
David Carlier
2ef71307c8 netfilter: ctnetlink: use netlink policy range checks
[ Upstream commit 8f15b5071b ]

Replace manual range and mask validations with netlink policy
annotations in ctnetlink code paths, so that the netlink core rejects
invalid values early and can generate extack errors.

- CTA_PROTOINFO_TCP_STATE: reject values > TCP_CONNTRACK_SYN_SENT2 at
  policy level, removing the manual >= TCP_CONNTRACK_MAX check.
- CTA_PROTOINFO_TCP_WSCALE_ORIGINAL/REPLY: reject values > TCP_MAX_WSCALE
  (14). The normal TCP option parsing path already clamps to this value,
  but the ctnetlink path accepted 0-255, causing undefined behavior when
  used as a u32 shift count.
- CTA_FILTER_ORIG_FLAGS/REPLY_FLAGS: use NLA_POLICY_MASK with
  CTA_FILTER_F_ALL, removing the manual mask checks.
- CTA_EXPECT_FLAGS: use NLA_POLICY_MASK with NF_CT_EXPECT_MASK, adding
  a new mask define grouping all valid expect flags.

Extracted from a broader nf-next patch by Florian Westphal, scoped to
ctnetlink for the fixes tree.

Fixes: c8e2078cfe ("[NETFILTER]: ctnetlink: add support for internal tcp connection tracking flags handling")
Signed-off-by: David Carlier <devnexen@gmail.com>
Co-developed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:25 +02:00
Florian Westphal
72f3c34de5 netlink: allow be16 and be32 types in all uint policy checks
[ Upstream commit 5fac9b7c16 ]

__NLA_IS_BEINT_TYPE(tp) isn't useful.  NLA_BE16/32 are identical to
NLA_U16/32, the only difference is that it tells the netlink validation
functions that byteorder conversion might be needed before comparing
the value to the policy min/max ones.

After this change all policy macros that can be used with UINT types,
such as NLA_POLICY_MASK() can also be used with NLA_BE16/32.

This will be used to validate nf_tables flag attributes which
are in bigendian byte order.

Signed-off-by: Florian Westphal <fw@strlen.de>
Stable-dep-of: 8f15b5071b ("netfilter: ctnetlink: use netlink policy range checks")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:25 +02:00
Florian Westphal
cbfac0add2 netlink: introduce bigendian integer types
[ Upstream commit ecaf75ffd5 ]

Jakub reported that the addition of the "network_byte_order"
member in struct nla_policy increases size of 32bit platforms.

Instead of scraping the bit from elsewhere Johannes suggested
to add explicit NLA_BE types instead, so do this here.

NLA_POLICY_MAX_BE() macro is removed again, there is no need
for it: NLA_POLICY_MAX(NLA_BE.., ..) will do the right thing.

NLA_BE64 can be added later.

Fixes: 08724ef699 ("netlink: introduce NLA_POLICY_MAX_BE")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Suggested-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20221031123407.9158-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 8f15b5071b ("netfilter: ctnetlink: use netlink policy range checks")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:25 +02:00
Jakub Kicinski
72eab86197 netlink: hide validation union fields from kdoc
[ Upstream commit 7354c9024f ]

Mark the validation fields as private, users shouldn't set
them directly and they are too complicated to explain in
a more succinct way (there's already a long explanation
in the comment above).

The strict_start_type field is set directly and has a dedicated
comment so move that above the "private" section.

Link: https://lore.kernel.org/r/20221027212107.2639255-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 8f15b5071b ("netfilter: ctnetlink: use netlink policy range checks")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:25 +02:00
Florian Westphal
dd9df463d7 netlink: introduce NLA_POLICY_MAX_BE
[ Upstream commit 08724ef699 ]

netlink allows to specify allowed ranges for integer types.
Unfortunately, nfnetlink passes integers in big endian, so the existing
NLA_POLICY_MAX() cannot be used.

At the moment, nfnetlink users, such as nf_tables, need to resort to
programmatic checking via helpers such as nft_parse_u32_check().

This is both cumbersome and error prone.  This adds NLA_POLICY_MAX_BE
which adds range check support for BE16, BE32 and BE64 integers.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 8f15b5071b ("netfilter: ctnetlink: use netlink policy range checks")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:25 +02:00
Miguel Ojeda
fa207e6c81 dma-mapping: add missing inline for dma_free_attrs
[ Upstream commit 2cdaff22ed ]

Under an UML build for an upcoming series [1], I got `-Wstatic-in-inline`
for `dma_free_attrs`:

      BINDGEN rust/bindings/bindings_generated.rs - due to target missing
    In file included from rust/helpers/helpers.c:59:
    rust/helpers/dma.c:17:2: warning: static function 'dma_free_attrs' is used in an inline function with external linkage [-Wstatic-in-inline]
       17 |         dma_free_attrs(dev, size, cpu_addr, dma_handle, attrs);
          |         ^
    rust/helpers/dma.c:12:1: note: use 'static' to give inline function 'rust_helper_dma_free_attrs' internal linkage
       12 | __rust_helper void rust_helper_dma_free_attrs(struct device *dev, size_t size,
          | ^
          | static

The issue is that `dma_free_attrs` was not marked `inline` when it was
introduced alongside the rest of the stubs.

Thus mark it.

Fixes: ed6ccf10f2 ("dma-mapping: properly stub out the DMA API for !CONFIG_HAS_DMA")
Closes: https://lore.kernel.org/rust-for-linux/20260322194616.89847-1-ojeda@kernel.org/ [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20260325015548.70912-1-ojeda@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:25 +02:00
Isaac J. Manjarres
b1ee8a1b2f dma-buf: Include ioctl.h in UAPI header
[ Upstream commit a116bac871 ]

include/uapi/linux/dma-buf.h uses several macros from ioctl.h to define
its ioctl commands. However, it does not include ioctl.h itself. So,
if userspace source code tries to include the dma-buf.h file without
including ioctl.h, it can result in build failures.

Therefore, include ioctl.h in the dma-buf UAPI header.

Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com>
Reviewed-by: T.J. Mercier <tjmercier@google.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20260303002309.1401849-1-isaacmanjarres@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:23 +02:00
Valentin Spreckels
c4b53c06ee net: usb: r8152: add TRENDnet TUC-ET2G
[ Upstream commit 15fba71533 ]

The TRENDnet TUC-ET2G is a RTL8156 based usb ethernet adapter. Add its
vendor and product IDs.

Signed-off-by: Valentin Spreckels <valentin@spreckels.dev>
Link: https://patch.msgid.link/20260226195409.7891-2-valentin@spreckels.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:23 +02:00
Juergen Gross
a5ea87cc1a xen/privcmd: add boot control for restricted usage in domU
commit 1613462be6 upstream.

When running in an unprivileged domU under Xen, the privcmd driver
is restricted to allow only hypercalls against a target domain, for
which the current domU is acting as a device model.

Add a boot parameter "unrestricted" to allow all hypercalls (the
hypervisor will still refuse destructive hypercalls affecting other
guests).

Make this new parameter effective only in case the domU wasn't started
using secure boot, as otherwise hypercalls targeting the domU itself
might result in violating the secure boot functionality.

This is achieved by adding another lockdown reason, which can be
tested to not being set when applying the "unrestricted" option.

This is part of XSA-482

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-18 10:33:22 +02:00
Florian Westphal
c0f1f85097 netfilter: nft_set_pipapo: split gc into unlink and reclaim phase
commit 9df95785d3 upstream.

Yiming Qian reports Use-after-free in the pipapo set type:
  Under a large number of expired elements, commit-time GC can run for a very
  long time in a non-preemptible context, triggering soft lockup warnings and
  RCU stall reports (local denial of service).

We must split GC in an unlink and a reclaim phase.

We cannot queue elements for freeing until pointers have been swapped.
Expired elements are still exposed to both the packet path and userspace
dumpers via the live copy of the data structure.

call_rcu() does not protect us: dump operations or element lookups starting
after call_rcu has fired can still observe the free'd element, unless the
commit phase has made enough progress to swap the clone and live pointers
before any new reader has picked up the old version.

This a similar approach as done recently for the rbtree backend in commit
35f83a7552 ("netfilter: nft_set_rbtree: don't gc elements on insert").

Fixes: 3c4287f620 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Reported-by: Yiming Qian <yimingqian591@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-18 10:33:22 +02:00
Florian Westphal
d725560f80 netfilter: nf_tables: de-constify set commit ops function argument
commit 2560016721 upstream.

The set backend using this already has to work around this via ugly
cast, don't spread this pattern.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-18 10:33:22 +02:00
Xiang Mei
66117dbb3d udp_tunnel: fix NULL deref caused by udp_sock_create6 when CONFIG_IPV6=n
[ Upstream commit b3a6df291f ]

When CONFIG_IPV6 is disabled, the udp_sock_create6() function returns 0
(success) without actually creating a socket. Callers such as
fou_create() then proceed to dereference the uninitialized socket
pointer, resulting in a NULL pointer dereference.

The captured NULL deref crash:
  BUG: kernel NULL pointer dereference, address: 0000000000000018
  RIP: 0010:fou_nl_add_doit (net/ipv4/fou_core.c:590 net/ipv4/fou_core.c:764)
  [...]
  Call Trace:
    <TASK>
    genl_family_rcv_msg_doit.constprop.0 (net/netlink/genetlink.c:1114)
    genl_rcv_msg (net/netlink/genetlink.c:1194 net/netlink/genetlink.c:1209)
    [...]
    netlink_rcv_skb (net/netlink/af_netlink.c:2550)
    genl_rcv (net/netlink/genetlink.c:1219)
    netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
    netlink_sendmsg (net/netlink/af_netlink.c:1894)
    __sock_sendmsg (net/socket.c:727 (discriminator 1) net/socket.c:742 (discriminator 1))
    __sys_sendto (./include/linux/file.h:62 (discriminator 1) ./include/linux/file.h:83 (discriminator 1) net/socket.c:2183 (discriminator 1))
    __x64_sys_sendto (net/socket.c:2213 (discriminator 1) net/socket.c:2209 (discriminator 1) net/socket.c:2209 (discriminator 1))
    do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
    entry_SYSCALL_64_after_hwframe (net/arch/x86/entry/entry_64.S:130)

This patch makes udp_sock_create6 return -EPFNOSUPPORT instead, so
callers correctly take their error paths. There is only one caller of
the vulnerable function and only privileged users can trigger it.

Fixes: fd384412e1 ("udp_tunnel: Seperate ipv6 functions into its own file.")
Reported-by: Weiming Shi <bestswngs@gmail.com>
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Link: https://patch.msgid.link/20260317010241.1893893-1-xmei5@asu.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:21 +02:00
Jonathan Cameron
7bce17b3c7 of: Add cleanup.h based auto release via __free(device_node) markings
[ Upstream commit 9448e55d03 ]

The recent addition of scope based cleanup support to the kernel
provides a convenient tool to reduce the chances of leaking reference
counts where of_node_put() should have been called in an error path.

This enables
	struct device_node *child __free(device_node) = NULL;

	for_each_child_of_node(np, child) {
		if (test)
			return test;
	}

with no need for a manual call of of_node_put().
A following patch will reduce the scope of the child variable to the
for loop, to avoid an issues with ordering of autocleanup, and make it
obvious when this assigned a non NULL value.

In this simple example the gains are small but there are some very
complex error handling cases buried in these loops that will be
greatly simplified by enabling early returns with out the need
for this manual of_node_put() call.

Note that there are coccinelle checks in
scripts/coccinelle/iterators/for_each_child.cocci to detect a failure
to call of_node_put(). This new approach does not cause false positives.
Longer term we may want to add scripting to check this new approach is
done correctly with no double of_node_put() calls being introduced due
to the auto cleanup. It may also be useful to script finding places
this new approach is useful.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20240225142714.286440-2-jic23@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Stable-dep-of: 879c001afb ("firmware: arm_scpi: Fix device_node reference leak in probe path")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-04-18 10:33:20 +02:00
David Hildenbrand (Red Hat)
ce4cf24761 mm/hugetlb: fix excessive IPI broadcasts when unsharing PMD tables using mmu_gather
commit 8ce720d5bd upstream.

As reported, ever since commit 1013af4f58 ("mm/hugetlb: fix
huge_pmd_unshare() vs GUP-fast race") we can end up in some situations
where we perform so many IPI broadcasts when unsharing hugetlb PMD page
tables that it severely regresses some workloads.

In particular, when we fork()+exit(), or when we munmap() a large
area backed by many shared PMD tables, we perform one IPI broadcast per
unshared PMD table.

There are two optimizations to be had:

(1) When we process (unshare) multiple such PMD tables, such as during
    exit(), it is sufficient to send a single IPI broadcast (as long as
    we respect locking rules) instead of one per PMD table.

    Locking prevents that any of these PMD tables could get reused before
    we drop the lock.

(2) When we are not the last sharer (> 2 users including us), there is
    no need to send the IPI broadcast. The shared PMD tables cannot
    become exclusive (fully unshared) before an IPI will be broadcasted
    by the last sharer.

    Concurrent GUP-fast could walk into a PMD table just before we
    unshared it. It could then succeed in grabbing a page from the
    shared page table even after munmap() etc succeeded (and supressed
    an IPI). But there is not difference compared to GUP-fast just
    sleeping for a while after grabbing the page and re-enabling IRQs.

    Most importantly, GUP-fast will never walk into page tables that are
    no-longer shared, because the last sharer will issue an IPI
    broadcast.

    (if ever required, checking whether the PUD changed in GUP-fast
     after grabbing the page like we do in the PTE case could handle
     this)

So let's rework PMD sharing TLB flushing + IPI sync to use the mmu_gather
infrastructure so we can implement these optimizations and demystify the
code at least a bit. Extend the mmu_gather infrastructure to be able to
deal with our special hugetlb PMD table sharing implementation.

To make initialization of the mmu_gather easier when working on a single
VMA (in particular, when dealing with hugetlb), provide
tlb_gather_mmu_vma().

We'll consolidate the handling for (full) unsharing of PMD tables in
tlb_unshare_pmd_ptdesc() and tlb_flush_unshared_tables(), and track
in "struct mmu_gather" whether we had (full) unsharing of PMD tables.

Because locking is very special (concurrent unsharing+reuse must be
prevented), we disallow deferring flushing to tlb_finish_mmu() and instead
require an explicit earlier call to tlb_flush_unshared_tables().

From hugetlb code, we call huge_pmd_unshare_flush() where we make sure
that the expected lock protecting us from concurrent unsharing+reuse is
still held.

Check with a VM_WARN_ON_ONCE() in tlb_finish_mmu() that
tlb_flush_unshared_tables() was properly called earlier.

Document it all properly.

Notes about tlb_remove_table_sync_one() interaction with unsharing:

There are two fairly tricky things:

(1) tlb_remove_table_sync_one() is a NOP on architectures without
    CONFIG_MMU_GATHER_RCU_TABLE_FREE.

    Here, the assumption is that the previous TLB flush would send an
    IPI to all relevant CPUs. Careful: some architectures like x86 only
    send IPIs to all relevant CPUs when tlb->freed_tables is set.

    The relevant architectures should be selecting
    MMU_GATHER_RCU_TABLE_FREE, but x86 might not do that in stable
    kernels and it might have been problematic before this patch.

    Also, the arch flushing behavior (independent of IPIs) is different
    when tlb->freed_tables is set. Do we have to enlighten them to also
    take care of tlb->unshared_tables? So far we didn't care, so
    hopefully we are fine. Of course, we could be setting
    tlb->freed_tables as well, but that might then unnecessarily flush
    too much, because the semantics of tlb->freed_tables are a bit
    fuzzy.

    This patch changes nothing in this regard.

(2) tlb_remove_table_sync_one() is not a NOP on architectures with
    CONFIG_MMU_GATHER_RCU_TABLE_FREE that actually don't need a sync.

    Take x86 as an example: in the common case (!pv, !X86_FEATURE_INVLPGB)
    we still issue IPIs during TLB flushes and don't actually need the
    second tlb_remove_table_sync_one().

    This optimized can be implemented on top of this, by checking e.g., in
    tlb_remove_table_sync_one() whether we really need IPIs. But as
    described in (1), it really must honor tlb->freed_tables then to
    send IPIs to all relevant CPUs.

Notes on TLB flushing changes:

(1) Flushing for non-shared PMD tables

    We're converting from flush_hugetlb_tlb_range() to
    tlb_remove_huge_tlb_entry(). Given that we properly initialize the
    MMU gather in tlb_gather_mmu_vma() to be hugetlb aware, similar to
    __unmap_hugepage_range(), that should be fine.

(2) Flushing for shared PMD tables

    We're converting from various things (flush_hugetlb_tlb_range(),
    tlb_flush_pmd_range(), flush_tlb_range()) to tlb_flush_pmd_range().

    tlb_flush_pmd_range() achieves the same that
    tlb_remove_huge_tlb_entry() would achieve in these scenarios.
    Note that tlb_remove_huge_tlb_entry() also calls
    __tlb_remove_tlb_entry(), however that is only implemented on
    powerpc, which does not support PMD table sharing.

    Similar to (1), tlb_gather_mmu_vma() should make sure that TLB
    flushing keeps on working as expected.

Further, note that the ptdesc_pmd_pts_dec() in huge_pmd_share() is not a
concern, as we are holding the i_mmap_lock the whole time, preventing
concurrent unsharing. That ptdesc_pmd_pts_dec() usage will be removed
separately as a cleanup later.

There are plenty more cleanups to be had, but they have to wait until
this is fixed.

[david@kernel.org: fix kerneldoc]
  Link: https://lkml.kernel.org/r/f223dd74-331c-412d-93fc-69e360a5006c@kernel.org
Link: https://lkml.kernel.org/r/20251223214037.580860-5-david@kernel.org
Fixes: 1013af4f58 ("mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race")
Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reported-by: "Uschakow, Stanislav" <suschako@amazon.de>
Closes: https://lore.kernel.org/all/4d3878531c76479d9f8ca9789dc6485d@amazon.de/
Tested-by: Laurence Oberman <loberman@redhat.com>
Acked-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Rik van Riel <riel@surriel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ David: We don't have ptdesc and the wrappers, so work directly on
  page->pt_share_count and pass "struct page" instead of "struct ptdesc".
  CONFIG_HUGETLB_PMD_PAGE_TABLE_SHARING is still called
  CONFIG_ARCH_WANT_HUGE_PMD_SHARE and is set even without
  CONFIG_HUGETLB_PAGE. We don't have 550a7d60bd ("mm, hugepages: add
  mremap() support for hugepage backed vma"), so move_hugetlb_page_tables()
  does not exist. We don't have 40549ba8f8 ("hugetlb: use new vma_lock
  for pmd sharing synchronization") so changes in mm/rmap.c looks quite
  different. We don't have 4ddb4d91b8 ("hugetlb: do not update address
  in huge_pmd_unshare"), so huge_pmd_unshare() still gets a pointer to
  an address. Some smaller contextual stuff. ]
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-18 10:33:18 +02:00
David Hildenbrand (Red Hat)
bf3c2affe2 mm/hugetlb: fix hugetlb_pmd_shared()
commit ca1a47cd3f upstream.

Patch series "mm/hugetlb: fixes for PMD table sharing (incl.  using
mmu_gather)", v3.

One functional fix, one performance regression fix, and two related
comment fixes.

I cleaned up my prototype I recently shared [1] for the performance fix,
deferring most of the cleanups I had in the prototype to a later point.
While doing that I identified the other things.

The goal of this patch set is to be backported to stable trees "fairly"
easily. At least patch #1 and #4.

Patch #1 fixes hugetlb_pmd_shared() not detecting any sharing
Patch #2 + #3 are simple comment fixes that patch #4 interacts with.
Patch #4 is a fix for the reported performance regression due to excessive
IPI broadcasts during fork()+exit().

The last patch is all about TLB flushes, IPIs and mmu_gather.
Read: complicated

There are plenty of cleanups in the future to be had + one reasonable
optimization on x86. But that's all out of scope for this series.

Runtime tested, with a focus on fixing the performance regression using
the original reproducer [2] on x86.


This patch (of 4):

We switched from (wrongly) using the page count to an independent shared
count.  Now, shared page tables have a refcount of 1 (excluding
speculative references) and instead use ptdesc->pt_share_count to identify
sharing.

We didn't convert hugetlb_pmd_shared(), so right now, we would never
detect a shared PMD table as such, because sharing/unsharing no longer
touches the refcount of a PMD table.

Page migration, like mbind() or migrate_pages() would allow for migrating
folios mapped into such shared PMD tables, even though the folios are not
exclusive.  In smaps we would account them as "private" although they are
"shared", and we would be wrongly setting the PM_MMAP_EXCLUSIVE in the
pagemap interface.

Fix it by properly using ptdesc_pmd_is_shared() in hugetlb_pmd_shared().

Link: https://lkml.kernel.org/r/20251223214037.580860-1-david@kernel.org
Link: https://lkml.kernel.org/r/20251223214037.580860-2-david@kernel.org
Link: https://lore.kernel.org/all/8cab934d-4a56-44aa-b641-bfd7e23bd673@kernel.org/ [1]
Link: https://lore.kernel.org/all/8cab934d-4a56-44aa-b641-bfd7e23bd673@kernel.org/ [2]
Fixes: 59d9094df3 ("mm: hugetlb: independent PMD page table shared count")
Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Tested-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: "Uschakow, Stanislav" <suschako@amazon.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ David: We don't have ptdesc and the wrappers, so work directly on
  page->pt_share_count. ]
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-18 10:33:18 +02:00
Marc Zyngier
0f9563b0e5 irqchip/gic-v3-its: Limit number of per-device MSIs to the range the ITS supports
commit ce9e40a9a5 upstream.

The ITS driver blindly assumes that EventIDs are in abundant supply, to the
point where it never checks how many the hardware actually supports.

It turns out that some pretty esoteric integrations make it so that only a
few bits are available, all the way down to a single bit.

Enforce the advertised limitation at the point of allocating the device
structure, and hope that the endpoint driver can deal with such limitation.

Fixes: 84a6a2e7fc ("irqchip: GICv3: ITS: device allocation and configuration")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Zenghui Yu <zenghui.yu@linux.dev>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260206154816.3582887-1-maz@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-18 10:33:15 +02:00