Similar to previous commit 2a934fdb01 ("media: v4l2-dev: fix error
handling in __video_register_device()"), the release hook should be set
before device_register(). Otherwise, when device_register() return error
and put_device() try to callback the release function, the below warning
may happen.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4760 at drivers/base/core.c:2567 device_release+0x1bd/0x240 drivers/base/core.c:2567
Modules linked in:
CPU: 1 UID: 0 PID: 4760 Comm: syz.4.914 Not tainted 6.17.0-rc3+ #1 NONE
RIP: 0010:device_release+0x1bd/0x240 drivers/base/core.c:2567
Call Trace:
<TASK>
kobject_cleanup+0x136/0x410 lib/kobject.c:689
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0xe9/0x130 lib/kobject.c:737
put_device+0x24/0x30 drivers/base/core.c:3797
pps_register_cdev+0x2da/0x370 drivers/pps/pps.c:402
pps_register_source+0x2f6/0x480 drivers/pps/kapi.c:108
pps_tty_open+0x190/0x310 drivers/pps/clients/pps-ldisc.c:57
tty_ldisc_open+0xa7/0x120 drivers/tty/tty_ldisc.c:432
tty_set_ldisc+0x333/0x780 drivers/tty/tty_ldisc.c:563
tiocsetd drivers/tty/tty_io.c:2429 [inline]
tty_ioctl+0x5d1/0x1700 drivers/tty/tty_io.c:2728
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:598 [inline]
__se_sys_ioctl fs/ioctl.c:584 [inline]
__x64_sys_ioctl+0x194/0x210 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x5f/0x2a0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
</TASK>
Before commit c79a39dc8d ("pps: Fix a use-after-free"),
pps_register_cdev() call device_create() to create pps->dev, which will
init dev->release to device_create_release(). Now the comment is outdated,
just remove it.
Thanks for the reminder from Calvin Owens, 'kfree_pps' should be removed
in pps_register_source() to avoid a double free in the failure case.
Link: https://lore.kernel.org/all/20250827065010.3208525-1-wangliang74@huawei.com/
Fixes: c79a39dc8d ("pps: Fix a use-after-free")
Signed-off-by: Wang Liang <wangliang74@huawei.com>
Reviewed-By: Calvin Owens <calvin@wbinvd.org>
Link: https://lore.kernel.org/r/20250830075023.3498174-1-wangliang74@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because pps_cdev_poll() returns unconditionally EPOLLIN,
a user space program that calls select/poll get always an immediate data
ready-to-read response. As a result the intended use to wait until next
data becomes ready does not work.
User space snippet:
struct pollfd pollfd = {
.fd = open("/dev/pps0", O_RDONLY),
.events = POLLIN|POLLERR,
.revents = 0 };
while(1) {
poll(&pollfd, 1, 2000/*ms*/); // returns immediate, but should wait
if(revents & EPOLLIN) { // always true
struct pps_fdata fdata;
memset(&fdata, 0, sizeof(memdata));
ioctl(PPS_FETCH, &fdata); // currently fetches data at max speed
}
}
Lets remember the last fetch event counter and compare this value
in pps_cdev_poll() with most recent event counter
and return 0 if they are equal.
Signed-off-by: Denis OSTERLAND-HEIM <denis.osterland@diehl.com>
Co-developed-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Rodolfo Giometti <giometti@enneenne.com>
Fixes: eae9d2ba0c ("LinuxPPS: core support")
Link: https://lore.kernel.org/all/f6bed779-6d59-4f0f-8a59-b6312bd83b4e@enneenne.com/
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Link: https://lore.kernel.org/r/c3c50ad1eb19ef553eca8a57c17f4c006413ab70.camel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The interrupt handler in pps_gpio_probe() is registered after calling
pps_register_source() using devm_request_irq(). However, in the
corresponding remove function, pps_unregister_source() is called before
the IRQ is freed, since devm-managed resources are released after the
remove function completes.
This creates a potential race condition where an interrupt may occur
after the PPS source is unregistered but before the handler is removed,
possibly leading to a kernel panic.
To prevent this, switch from devm-managed IRQ registration to manual
management by using request_irq() and calling free_irq() explicitly in
the remove path before unregistering the PPS source. This ensures the
interrupt handler is safely removed before deactivating the PPS source.
Signed-off-by: Eliav Farber <farbere@amazon.com>
Link: https://lore.kernel.org/r/20250527053355.37185-1-farbere@amazon.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
platform_set_drvdata() is setting a double pointer to struct pps_tio as
driver_data, which will point to the local stack of probe function instead
of intended data. Set driver_data correctly and fix illegal memory access
by its user.
BUG: unable to handle page fault for address: ffffc9000117b738
RIP: 0010:hrtimer_active+0x2b/0x60
Call Trace:
? hrtimer_active+0x2b/0x60
hrtimer_cancel+0x19/0x50
pps_gen_tio_remove+0x1e/0x80 [pps_gen_tio]
Fixes: c89755d111 ("pps: generators: Add PPS Generator TIO Driver")
Signed-off-by: Raag Jadav <raag.jadav@intel.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250318114038.2058677-1-raag.jadav@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.
Replace hrtimer_init() and the open coded initialization of
hrtimer::function with the new setup mechanism.
Coccinelle scripted cleanup.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.
Conversion was done with coccinelle plus manual fixups where necessary.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull char / misc / IIO driver updates from Greg KH:
"Here is the big set of char, misc, iio, and other smaller driver
subsystems for 6.15-rc1. Lots of stuff in here, including:
- loads of IIO changes and driver updates
- counter driver updates
- w1 driver updates
- faux conversions for some drivers that were abusing the platform
bus interface
- coresight driver updates
- rust miscdevice binding updates based on real-world-use
- other minor driver updates
All of these have been in linux-next with no reported issues for quite
a while"
* tag 'char-misc-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits)
samples: rust_misc_device: fix markup in top-level docs
Coresight: Fix a NULL vs IS_ERR() bug in probe
misc: lis3lv02d: convert to use faux_device
tlclk: convert to use faux_device
regulator: dummy: convert to use the faux device interface
bus: mhi: host: Fix race between unprepare and queue_buf
coresight: configfs: Constify struct config_item_type
doc: iio: ad7380: describe offload support
iio: ad7380: add support for SPI offload
iio: light: Add check for array bounds in veml6075_read_int_time_ms
iio: adc: ti-ads7924 Drop unnecessary function parameters
staging: iio: ad9834: Use devm_regulator_get_enable()
staging: iio: ad9832: Use devm_regulator_get_enable()
iio: gyro: bmg160_spi: add of_match_table
dt-bindings: iio: adc: Add i.MX94 and i.MX95 support
iio: adc: ad7768-1: remove unnecessary locking
Documentation: ABI: add wideband filter type to sysfs-bus-iio
iio: adc: ad7768-1: set MOSI idle state to prevent accidental reset
iio: adc: ad7768-1: Fix conversion result sign
iio: adc: ad7124: Benefit of dev = indio_dev->dev.parent in ad7124_parse_channel_config()
...
The Intel Timed IO PPS generator driver outputs a PPS signal using
dedicated hardware that is more accurate than software actuated PPS.
The Timed IO hardware generates output events using the ART timer.
The ART timer period varies based on platform type, but is less than 100
nanoseconds for all current platforms. Timed IO output accuracy is
within 1 ART period.
PPS output is enabled by writing '1' the 'enable' sysfs attribute. The
driver uses hrtimers to schedule a wake-up 10 ms before each event
(edge) target time. At wakeup, the driver converts the target time in
terms of CLOCK_REALTIME to ART trigger time and writes this to the Timed
IO hardware. The Timed IO hardware generates an event precisely at the
requested system time without software involvement.
Co-developed-by: Christopher Hall <christopher.s.hall@intel.com>
Signed-off-by: Christopher Hall <christopher.s.hall@intel.com>
Co-developed-by: Pandith N <pandith.n@intel.com>
Signed-off-by: Pandith N <pandith.n@intel.com>
Co-developed-by: Thejesh Reddy T R <thejesh.reddy.t.r@intel.com>
Signed-off-by: Thejesh Reddy T R <thejesh.reddy.t.r@intel.com>
Signed-off-by: Lakshmi Sowjanya D <lakshmi.sowjanya.d@intel.com>
Reviewed-by: Eddie Dong <eddie.dong@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Subramanian Mohan <subramanian.mohan@intel.com>
Link: https://lore.kernel.org/r/20250219040618.70962-3-subramanian.mohan@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some PPS generator drivers may need to retrieve a pointer to their
internal data while executing the PPS generator enable() method.
During the driver registration the pps_gen_device pointer is returned
from the framework, and for that reason, there is difficulty in
getting generator driver data back in the enable function. We won't be
able to use container_of macro as it results in static assert, and we
might end up in using static pointer.
To solve the issue and to get back the generator driver data back, we
should not copy the struct pps_gen_source_info within the struct
pps_gen_device during the registration stage, but simply save the
pointer of the driver one. In this manner, driver may get a pointer
to their internal data as shown below:
struct pps_gen_foo_data_s {
...
struct pps_gen_source_info gen_info;
struct pps_gen_device *pps_gen;
...
};
static int __init pps_gen_foo_init(void)
{
struct pps_gen_foo_data_s *foo;
...
foo->pps_gen = pps_gen_register_source(&foo->gen_info);
...
}
Then, in the enable() method, we can retrieve the pointer to the main
struct by using the code below:
static int pps_gen_foo_enable(struct pps_gen_device *pps_gen, bool enable)
{
struct pps_gen_foo_data_s *foo = container_of(pps_gen->info,
struct pps_gen_foo_data_s, gen_info);
...
}
Signed-off-by: Rodolfo Giometti <giometti@enneenne.com>
Tested-by: Subramanian Mohan <subramanian.mohan@intel.com>
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Subramanian Mohan <subramanian.mohan@intel.com>
Link: https://lore.kernel.org/r/20250219040618.70962-2-subramanian.mohan@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the IRQ handler, the GPIO's state is read to verify the direction of
the edge that triggered the interruption before generating the PPS event.
If a pulse is too short, the GPIO line can reach back its original state
before this verification and the PPS event is lost.
This check is needed when info->capture_clear is set because it needs
interruptions on both rising and falling edges. When info->capture_clear
is not set, interruption is triggered by one edge only so this check can
be omitted.
Add a warning if irq_handler is left without triggering any PPS event.
Bypass the edge's direction verification when info->capture_clear is not
set.
Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Link: https://lore.kernel.org/r/20250108153012.514925-1-bastien.curutchet@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sometimes one needs to be able not only to catch PPS signals but to
produce them also. For example, running a distributed simulation,
which requires computers' clock to be synchronized very tightly.
This patch adds PPS generators class in order to have a well-defined
interface for these devices.
Signed-off-by: Rodolfo Giometti <giometti@enneenne.com>
Link: https://lore.kernel.org/r/20241108073115.759039-2-giometti@enneenne.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On a board running ntpd and gpsd, I'm seeing a consistent use-after-free
in sys_exit() from gpsd when rebooting:
pps pps1: removed
------------[ cut here ]------------
kobject: '(null)' (00000000db4bec24): is not initialized, yet kobject_put() is being called.
WARNING: CPU: 2 PID: 440 at lib/kobject.c:734 kobject_put+0x120/0x150
CPU: 2 UID: 299 PID: 440 Comm: gpsd Not tainted 6.11.0-rc6-00308-gb31c44928842 #1
Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT)
pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : kobject_put+0x120/0x150
lr : kobject_put+0x120/0x150
sp : ffffffc0803d3ae0
x29: ffffffc0803d3ae0 x28: ffffff8042dc9738 x27: 0000000000000001
x26: 0000000000000000 x25: ffffff8042dc9040 x24: ffffff8042dc9440
x23: ffffff80402a4620 x22: ffffff8042ef4bd0 x21: ffffff80405cb600
x20: 000000000008001b x19: ffffff8040b3b6e0 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 696e6920746f6e20
x14: 7369203a29343263 x13: 205d303434542020 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
kobject_put+0x120/0x150
cdev_put+0x20/0x3c
__fput+0x2c4/0x2d8
____fput+0x1c/0x38
task_work_run+0x70/0xfc
do_exit+0x2a0/0x924
do_group_exit+0x34/0x90
get_signal+0x7fc/0x8c0
do_signal+0x128/0x13b4
do_notify_resume+0xdc/0x160
el0_svc+0xd4/0xf8
el0t_64_sync_handler+0x140/0x14c
el0t_64_sync+0x190/0x194
---[ end trace 0000000000000000 ]---
...followed by more symptoms of corruption, with similar stacks:
refcount_t: underflow; use-after-free.
kernel BUG at lib/list_debug.c:62!
Kernel panic - not syncing: Oops - BUG: Fatal exception
This happens because pps_device_destruct() frees the pps_device with the
embedded cdev immediately after calling cdev_del(), but, as the comment
above cdev_del() notes, fops for previously opened cdevs are still
callable even after cdev_del() returns. I think this bug has always
been there: I can't explain why it suddenly started happening every time
I reboot this particular board.
In commit d953e0e837 ("pps: Fix a use-after free bug when
unregistering a source."), George Spelvin suggested removing the
embedded cdev. That seems like the simplest way to fix this, so I've
implemented his suggestion, using __register_chrdev() with pps_idr
becoming the source of truth for which minor corresponds to which
device.
But now that pps_idr defines userspace visibility instead of cdev_add(),
we need to be sure the pps->dev refcount can't reach zero while
userspace can still find it again. So, the idr_remove() call moves to
pps_unregister_cdev(), and pps_idr now holds a reference to pps->dev.
pps_core: source serial1 got cdev (251:1)
<...>
pps pps1: removed
pps_core: unregistering pps1
pps_core: deallocating pps1
Fixes: d953e0e837 ("pps: Fix a use-after free bug when unregistering a source.")
Cc: stable@vger.kernel.org
Signed-off-by: Calvin Owens <calvin@wbinvd.org>
Reviewed-by: Michal Schmidt <mschmidt@redhat.com>
Link: https://lore.kernel.org/r/a17975fd5ae99385791929e563f72564edbcf28f.1731383727.git.calvin@wbinvd.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The continual trickle of small conversion patches is grating on me, and
is really not helping. Just get rid of the 'remove_new' member
function, which is just an alias for the plain 'remove', and had a
comment to that effect:
/*
* .remove_new() is a relic from a prototype conversion of .remove().
* New drivers are supposed to implement .remove(). Once all drivers are
* converted to not use .remove_new any more, it will be dropped.
*/
This was just a tree-wide 'sed' script that replaced '.remove_new' with
'.remove', with some care taken to turn a subsequent tab into two tabs
to make things line up.
I did do some minimal manual whitespace adjustment for places that used
spaces to line things up.
Then I just removed the old (sic) .remove_new member function, and this
is the end result. No more unnecessary conversion noise.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
no_llseek had been defined to NULL two years ago, in commit 868941b144
("fs: remove no_llseek")
To quote that commit,
At -rc1 we'll need do a mechanical removal of no_llseek -
git grep -l -w no_llseek | grep -v porting.rst | while read i; do
sed -i '/\<no_llseek\>/d' $i
done
would do it.
Unfortunately, that hadn't been done. Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
.llseek = no_llseek,
so it's obviously safe.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull driver core updates from Greg KH:
"Here is the big set of driver core changes for 6.11-rc1.
Lots of stuff in here, with not a huge diffstat, but apis are evolving
which required lots of files to be touched. Highlights of the changes
in here are:
- platform remove callback api final fixups (Uwe took many releases
to get here, finally!)
- Rust bindings for basic firmware apis and initial driver-core
interactions.
It's not all that useful for a "write a whole driver in rust" type
of thing, but the firmware bindings do help out the phy rust
drivers, and the driver core bindings give a solid base on which
others can start their work.
There is still a long way to go here before we have a multitude of
rust drivers being added, but it's a great first step.
- driver core const api changes.
This reached across all bus types, and there are some fix-ups for
some not-common bus types that linux-next and 0-day testing shook
out.
This work is being done to help make the rust bindings more safe,
as well as the C code, moving toward the end-goal of allowing us to
put driver structures into read-only memory. We aren't there yet,
but are getting closer.
- minor devres cleanups and fixes found by code inspection
- arch_topology minor changes
- other minor driver core cleanups
All of these have been in linux-next for a very long time with no
reported problems"
* tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
ARM: sa1100: make match function take a const pointer
sysfs/cpu: Make crash_hotplug attribute world-readable
dio: Have dio_bus_match() callback take a const *
zorro: make match function take a const pointer
driver core: module: make module_[add|remove]_driver take a const *
driver core: make driver_find_device() take a const *
driver core: make driver_[create|remove]_file take a const *
firmware_loader: fix soundness issue in `request_internal`
firmware_loader: annotate doctests as `no_run`
devres: Correct code style for functions that return a pointer type
devres: Initialize an uninitialized struct member
devres: Fix memory leakage caused by driver API devm_free_percpu()
devres: Fix devm_krealloc() wasting memory
driver core: platform: Switch to use kmemdup_array()
driver core: have match() callback in struct bus_type take a const *
MAINTAINERS: add Rust device abstractions to DRIVER CORE
device: rust: improve safety comments
MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer
MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER
firmware: rust: improve safety comments
...
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Link: https://lore.kernel.org/r/f4b9402af72e5f285c8b0f068076a76418f653f5.1709886922.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Wang Liang
Denis OSTERLAND-HEIM
Eliav Farber
Ingo Molnar
Raag Jadav
Thomas Gleixner
Linus Torvalds
Subramanian Mohan
Nam Cao
Bastien Curutchet
Rodolfo Giometti
Calvin Owens
Al Viro
Ma Ke
Dr. David Alan Gilbert
Uwe Kleine-König
Christophe JAILLET
Lukas Bulwahn
Greg Kroah-Hartman
Ilpo Järvinen