commit 12f65d1203 upstream.
Both new_device_store and delete_device_store touch module global
resources (e.g. gpio_aggregator_lock). To prevent race conditions with
module unload, a reference needs to be held.
Add try_module_get() in these handlers.
For new_device_store, this eliminates what appears to be the most dangerous
scenario: if an id is allocated from gpio_aggregator_idr but
platform_device_register has not yet been called or completed, a concurrent
module unload could fail to unregister/delete the device, leaving behind a
dangling platform device/GPIO forwarder. This can result in various issues.
The following simple reproducer demonstrates these problems:
#!/bin/bash
while :; do
# note: whether 'gpiochip0 0' exists or not does not matter.
echo 'gpiochip0 0' > /sys/bus/platform/drivers/gpio-aggregator/new_device
done &
while :; do
modprobe gpio-aggregator
modprobe -r gpio-aggregator
done &
wait
Starting with the following warning, several kinds of warnings will appear
and the system may become unstable:
------------[ cut here ]------------
list_del corruption, ffff888103e2e980->next is LIST_POISON1 (dead000000000100)
WARNING: CPU: 1 PID: 1327 at lib/list_debug.c:56 __list_del_entry_valid_or_report+0xa3/0x120
[...]
RIP: 0010:__list_del_entry_valid_or_report+0xa3/0x120
[...]
Call Trace:
<TASK>
? __list_del_entry_valid_or_report+0xa3/0x120
? __warn.cold+0x93/0xf2
? __list_del_entry_valid_or_report+0xa3/0x120
? report_bug+0xe6/0x170
? __irq_work_queue_local+0x39/0xe0
? handle_bug+0x58/0x90
? exc_invalid_op+0x13/0x60
? asm_exc_invalid_op+0x16/0x20
? __list_del_entry_valid_or_report+0xa3/0x120
gpiod_remove_lookup_table+0x22/0x60
new_device_store+0x315/0x350 [gpio_aggregator]
kernfs_fop_write_iter+0x137/0x1f0
vfs_write+0x262/0x430
ksys_write+0x60/0xd0
do_syscall_64+0x6c/0x180
entry_SYSCALL_64_after_hwframe+0x76/0x7e
[...]
</TASK>
---[ end trace 0000000000000000 ]---
Fixes: 828546e242 ("gpio: Add GPIO Aggregator")
Cc: stable@vger.kernel.org
Signed-off-by: Koichiro Den <koichiro.den@canonical.com>
Link: https://lore.kernel.org/r/20250224143134.3024598-2-koichiro.den@canonical.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b9644fbfbc upstream.
The stmpe_reg_read function can fail, but its return value is not checked
in stmpe_gpio_irq_sync_unlock. This can lead to silent failures and
incorrect behavior if the hardware access fails.
This patch adds checks for the return value of stmpe_reg_read. If the
function fails, an error message is logged and the function returns
early to avoid further issues.
Fixes: b888fb6f2a ("gpio: stmpe: i2c transfer are forbiden in atomic context")
Cc: stable@vger.kernel.org # 4.16+
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Link: https://lore.kernel.org/r/20250212021849.275-1-vulab@iscas.ac.cn
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 57f5db77a9 ]
The settings for all GPIOs are locked by default in bcm_kona_gpio_reset.
The settings for a GPIO are unlocked when requesting it as a GPIO, but
not when requesting it as an interrupt, causing the IRQ settings to not
get applied.
Fix this by making sure to unlock the right bits when an IRQ is requested.
To avoid a situation where an IRQ being released causes a lock despite
the same GPIO being used by a GPIO request or vice versa, add an unlock
counter and only lock if it reaches 0.
Fixes: 757651e3d6 ("gpio: bcm281xx: Add GPIO driver")
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Markus Mayer <mmayer@broadcom.com>
Signed-off-by: Artur Weber <aweber.kernel@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250206-kona-gpio-fixes-v2-2-409135eab780@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d6179f6c62 ]
The GPIO drivers with latch interrupt support (typically types starting
with PCAL) have interrupt status registers to determine which particular
inputs have caused an interrupt. Unfortunately there is no atomic
operation to read these registers and clear the interrupt. Clearing the
interrupt is done by reading the input registers.
The code was reading the interrupt status registers, and then reading
the input registers. If an input changed between these two events it was
lost.
The solution in this patch is to revert to the non-latch version of
code, i.e. remembering the previous input status, and looking for the
changes. This system results in no more I2C transfers, so is no slower.
The latch property of the device still means interrupts will still be
noticed if the input changes back to its initial state.
Fixes: 44896beae6 ("gpio: pca953x: add PCAL9535 interrupt support for Galileo Gen2")
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240606033102.2271916-1-mark.tomlinson@alliedtelesis.co.nz
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 53c59d66c4 ]
Curtrently the error path is unsynchronised with removal due to
regulator being disabled before other device managed resources
are handled. Correct that by wrapping regulator enablement in
the respective call.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Stable-dep-of: 7cef813a91 ("gpio: pca953x: log an error when failing to get the reset GPIO")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9722c3b66e ]
The of_property_for_each_u32() macro needs five parameters, two of which
are primarily meant as internal variables for the macro itself (in the
for() clause). Yet these two parameters are used by a few drivers, and this
can be considered misuse or at least bad practice.
Now that the kernel uses C11 to build, these two parameters can be avoided
by declaring them internally, thus changing this pattern:
struct property *prop;
const __be32 *p;
u32 val;
of_property_for_each_u32(np, "xyz", prop, p, val) { ... }
to this:
u32 val;
of_property_for_each_u32(np, "xyz", val) { ... }
However two variables cannot be declared in the for clause even with C11,
so declare one struct that contain the two variables we actually need. As
the variables inside this struct are not meant to be used by users of this
macro, give the struct instance the noticeable name "_it" so it is visible
during code reviews, helping to avoid new code to use it directly.
Most usages are trivially converted as they do not use those two
parameters, as expected. The non-trivial cases are:
- drivers/clk/clk.c, of_clk_get_parent_name(): easily doable anyway
- drivers/clk/clk-si5351.c, si5351_dt_parse(): this is more complex as the
checks had to be replicated in a different way, making code more verbose
and somewhat uglier, but I refrained from a full rework to keep as much
of the original code untouched having no hardware to test my changes
All the changes have been build tested. The few for which I have the
hardware have been runtime-tested too.
Reviewed-by: Andre Przywara <andre.przywara@arm.com> # drivers/clk/sunxi/clk-simple-gates.c, drivers/clk/sunxi/clk-sun8i-bus-gates.c
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> # drivers/gpio/gpio-brcmstb.c
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> # drivers/irqchip/irq-atmel-aic-common.c
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # drivers/iio/adc/ti_am335x_adc.c
Acked-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> # drivers/pwm/pwm-samsung.c
Acked-by: Richard Leitner <richard.leitner@linux.dev> # drivers/usb/misc/usb251xb.c
Acked-by: Mark Brown <broonie@kernel.org> # sound/soc/codecs/arizona.c
Reviewed-by: Richard Fitzgerald <rf@opensource.cirrus.com> # sound/soc/codecs/arizona.c
Acked-by: Michael Ellerman <mpe@ellerman.id.au> # arch/powerpc/sysdev/xive/spapr.c
Acked-by: Stephen Boyd <sboyd@kernel.org> # clk
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Acked-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20240724-of_property_for_each_u32-v3-1-bea82ce429e2@bootlin.com
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Stable-dep-of: 28fa3291ca ("clk: fix an OF node reference leak in of_clk_get_parent_name()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 72cef64180 upstream.
Setting GPIO direction = high, sometimes results in GPIO value = 0.
If a GPIO is pulled high, the following construction results in the
value being 0 when the desired value is 1:
$ echo "high" > /sys/class/gpio/gpio336/direction
$ cat /sys/class/gpio/gpio336/value
0
Before the GPIO direction is changed from an input to an output,
exar_set_value() is called with value = 1, but since the GPIO is an
input when exar_set_value() is called, _regmap_update_bits() reads a 1
due to an external pull-up. regmap_set_bits() sets force_write =
false, so the value (1) is not written. When the direction is then
changed, the GPIO becomes an output with the value of 0 (the hardware
default).
regmap_write_bits() sets force_write = true, so the value is always
written by exar_set_value() and an external pull-up doesn't affect the
outcome of setting direction = high.
The same can happen when a GPIO is pulled low, but the scenario is a
little more complicated.
$ echo high > /sys/class/gpio/gpio351/direction
$ cat /sys/class/gpio/gpio351/value
1
$ echo in > /sys/class/gpio/gpio351/direction
$ cat /sys/class/gpio/gpio351/value
0
$ echo low > /sys/class/gpio/gpio351/direction
$ cat /sys/class/gpio/gpio351/value
1
Fixes: 36fb7218e8 ("gpio: exar: switch to using regmap")
Co-developed-by: Matthew McClain <mmcclain@noprivs.com>
Signed-off-by: Matthew McClain <mmcclain@noprivs.com>
Signed-off-by: Sai Kumar Cholleti <skmr537@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20241105071523.2372032-1-skmr537@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1bb5a99e1f ]
Performing a dummy read ensures that the register write operation is fully
completed, mitigating any potential bus delays that could otherwise impact
the frequency of bitbang usage. E.g., if the JTAG application uses GPIO to
control the JTAG pins (TCK, TMS, TDI, TDO, and TRST), and the application
sets the TCK clock to 1 MHz, the GPIO's high/low transitions will rely on
a delay function to ensure the clock frequency does not exceed 1 MHz.
However, this can lead to rapid toggling of the GPIO because the write
operation is POSTed and does not wait for a bus acknowledgment.
Fixes: 361b79119a ("gpio: Add Aspeed driver")
Reviewed-by: Andrew Jeffery <andrew@codeconstruct.com.au>
Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20241008081450.1490955-2-billy_tsai@aspeedtech.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit b440396387 upstream.
linereq_set_config() behaves badly when direction is not set.
The configuration validation is borrowed from linereq_create(), where,
to verify the intent of the user, the direction must be set to in order to
effect a change to the electrical configuration of a line. But, when
applied to reconfiguration, that validation does not allow for the unset
direction case, making it possible to clear flags set previously without
specifying the line direction.
Adding to the inconsistency, those changes are not immediately applied by
linereq_set_config(), but will take effect when the line value is next get
or set.
For example, by requesting a configuration with no flags set, an output
line with GPIO_V2_LINE_FLAG_ACTIVE_LOW and GPIO_V2_LINE_FLAG_OPEN_DRAIN
set could have those flags cleared, inverting the sense of the line and
changing the line drive to push-pull on the next line value set.
Skip the reconfiguration of lines for which the direction is not set, and
only reconfigure the lines for which direction is set.
Fixes: a54756cb24 ("gpiolib: cdev: support GPIO_V2_LINE_SET_CONFIG_IOCTL")
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20240626052925.174272-3-warthog618@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit aad4183232 ]
During Linux graceful reboot, the GPIO interrupts are not disabled.
Since the drivers are not removed during graceful reboot,
the logic to call mlxbf3_gpio_irq_disable() is not triggered.
Interrupts that remain enabled can cause issues on subsequent boots.
For example, the mlxbf-gige driver contains PHY logic to bring up the link.
If the gpio-mlxbf3 driver loads first, the mlxbf-gige driver
will use a GPIO interrupt to bring up the link.
Otherwise, it will use polling.
The next time Linux boots and loads the drivers in this order, we encounter the issue:
- mlxbf-gige loads first and uses polling while the GPIO10
interrupt is still enabled from the previous boot. So if
the interrupt triggers, there is nothing to clear it.
- gpio-mlxbf3 loads.
- i2c-mlxbf loads. The interrupt doesn't trigger for I2C
because it is shared with the GPIO interrupt line which
was not cleared.
The solution is to add a shutdown function to the GPIO driver to clear and disable
all interrupts. Also clear the interrupt after disabling it in mlxbf3_gpio_irq_disable().
Fixes: 38a700efc5 ("gpio: mlxbf3: Add gpio driver support")
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Reviewed-by: David Thompson <davthompson@nvidia.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20240611171509.22151-1-asmaa@nvidia.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d795848ecc ]
Userspace may trigger a speculative read of an address outside the gpio
descriptor array.
Users can do that by calling gpio_ioctl() with an offset out of range.
Offset is copied from user and then used as an array index to get
the gpio descriptor without sanitization in gpio_device_get_desc().
This change ensures that the offset is sanitized by using
array_index_nospec() to mitigate any possibility of speculative
information leaks.
This bug was discovered and resolved using Coverity Static Analysis
Security Testing (SAST) by Synopsys, Inc.
Signed-off-by: Hagar Hemdan <hagarhem@amazon.com>
Link: https://lore.kernel.org/r/20240523085332.1801-1-hagarhem@amazon.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bfc6444b57 ]
Ensure that `i2c_lock' is held when setting interrupt latch and mask in
pca953x_irq_bus_sync_unlock() in order to avoid races.
The other (non-probe) call site pca953x_gpio_set_multiple() ensures the
lock is held before calling pca953x_write_regs().
The problem occurred when a request raced against irq_bus_sync_unlock()
approximately once per thousand reboots on an i.MX8MP based system.
* Normal case
0-0022: write register AI|3a {03,02,00,00,01} Input latch P0
0-0022: write register AI|49 {fc,fd,ff,ff,fe} Interrupt mask P0
0-0022: write register AI|08 {ff,00,00,00,00} Output P3
0-0022: write register AI|12 {fc,00,00,00,00} Config P3
* Race case
0-0022: write register AI|08 {ff,00,00,00,00} Output P3
0-0022: write register AI|08 {03,02,00,00,01} *** Wrong register ***
0-0022: write register AI|12 {fc,00,00,00,00} Config P3
0-0022: write register AI|49 {fc,fd,ff,ff,fe} Interrupt mask P0
Signed-off-by: Ian Ray <ian.ray@gehealthcare.com>
Link: https://lore.kernel.org/r/20240620042915.2173-1-ian.ray@gehealthcare.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3645ffaf2b ]
As it turns out, there is a large number of out-of-tree DTSes (in
OpenWrt project) that used to specify incorrect (active high) polarity
for the Lantiq reset GPIO, so to keep compatibility while they are
being updated a quirk for force the polarity low is needed. Luckily
these old DTSes used nonstandard name for the property ("gpio-reset" vs
"reset-gpios") so the quirk will not hurt if there are any new devices
that need inverted polarity as they can specify the right polarity in
their DTS when using the standard "reset-gpios" property.
Additionally the condition to enable the transition from standard to
non-standard reset GPIO property name was inverted and the replacement
name for the property was not correct. Fix this as well.
Fixes: fbbbcd177a ("gpiolib: of: add quirk for locating reset lines with legacy bindings")
Fixes: 90c2d2eb7a ("MIPS: pci: lantiq: switch to using gpiod API")
Reported-by: Martin Schiller <ms@dev.tdt.de>
Acked-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Link: https://lore.kernel.org/r/ZoLpqv1PN08xHioh@google.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9919cce62f ]
linehandle_set_config() behaves badly when direction is not set.
The configuration validation is borrowed from linehandle_create(), where,
to verify the intent of the user, the direction must be set to in order
to effect a change to the electrical configuration of a line. But, when
applied to reconfiguration, that validation does not allow for the unset
direction case, making it possible to clear flags set previously without
specifying the line direction.
Adding to the inconsistency, those changes are not immediately applied by
linehandle_set_config(), but will take effect when the line value is next
get or set.
For example, by requesting a configuration with no flags set, an output
line with GPIOHANDLE_REQUEST_ACTIVE_LOW and GPIOHANDLE_REQUEST_OPEN_DRAIN
requested could have those flags cleared, inverting the sense of the line
and changing the line drive to push-pull on the next line value set.
Ensure the intent of the user by disallowing configurations which do not
have direction set, returning an error to userspace to indicate that the
configuration is invalid.
And, for clarity, use lflags, a local copy of gcnf.flags, throughout when
dealing with the requested flags, rather than a mixture of both.
Fixes: e588bb1eae ("gpio: add new SET_CONFIG ioctl() to gpio chardev")
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20240626052925.174272-2-warthog618@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7aa9b96e9a ]
Value of pdata->gpio_unbanked is taken from Device Tree. In case of broken
DT due to any error this value can be any. Without this value validation
there can be out of chips->irqs array boundaries access in
davinci_gpio_probe().
Validate the obtained nirq value so that it won't exceed the maximum
number of IRQs per bank.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: eb3744a2dd ("gpio: davinci: Do not assume continuous IRQ numbering")
Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru>
Link: https://lore.kernel.org/r/20240618144344.16943-1-amishin@t-argos.ru
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9d6a811b52 ]
The TQMx86 GPIO controller uses the same register address for input and
output data. Reading the register will always return current inputs
rather than the previously set outputs (regardless of the current
direction setting). Therefore, using a RMW pattern does not make sense
when setting output values. Instead, the previously set output register
value needs to be stored as a shadow register.
As there is no reliable way to get the current output values from the
hardware, also initialize all channels to 0, to ensure that stored and
actual output values match. This should usually not have any effect in
practise, as the TQMx86 UEFI sets all outputs to 0 during boot.
Also prepare for extension of the driver to more than 8 GPIOs by using
DECLARE_BITMAP.
Fixes: b868db94a6 ("gpio: tqmx86: Add GPIO from for this IO controller")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/d0555933becd45fa92a85675d26e4d59343ddc01.1717063994.git.matthias.schiffer@ew.tq-group.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit adbc49a5a8 ]
Previous patch modified the standard used by acpi_gpiochip_find()
to match device nodes. Using the device node set in gc->gpiodev->d-
ev instead of gc->parent.
However, there is a situation in gpio-dwapb where the GPIO device
driver will set gc->fwnode for each port corresponding to a child
node under a GPIO device, so gc->gpiodev->dev will be assigned the
value of each child node in gpiochip_add_data().
gpio-dwapb.c:
128,31 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
struct dwapb_port_property *pp,
unsigned int offs);
port->gc.fwnode = pp->fwnode;
693,39 static int dwapb_gpio_probe;
err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
When other drivers request GPIO pin resources through the GPIO device
node provided by ACPI (corresponding to the parent node), the change
of the matching object to gc->gpiodev->dev in acpi_gpiochip_find()
only allows finding the value of each port (child node), resulting
in a failed request.
Reapply the condition of using gc->parent for match in acpi_gpio-
chip_find() in the code can compatible with the problem of gpio-dwapb,
and will not affect the two cases mentioned in the patch:
1. There is no setting for gc->fwnode.
2. The case that depends on using gc->fwnode for match.
Fixes: 5062e4c14b ("gpiolib: acpi: use the fwnode in acpi_gpiochip_find()")
Fixes: 067dbc1ea5 ("gpiolib: acpi: Don't use GPIO chip fwnode in acpi_gpiochip_find()")
Signed-off-by: Devyn Liu <liudingyuan@huawei.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Benjamin Tissoires <bentiss@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ee0166b637 ]
If a line is requested with debounce, and that results in debouncing
in software, and the line is subsequently reconfigured to enable edge
detection then the allocation of the kfifo to contain edge events is
overlooked. This results in events being written to and read from an
uninitialised kfifo. Read events are returned to userspace.
Initialise the kfifo in the case where the software debounce is
already active.
Fixes: 65cff70464 ("gpiolib: cdev: support setting debounce")
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20240510065342.36191-1-warthog618@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9344e34e79 ]
Store the debounce period for a requested line locally, rather than in
the debounce_period_us field in the gpiolib struct gpio_desc.
Add a global tree of lines containing supplemental line information
to make the debounce period available to be reported by the
GPIO_V2_GET_LINEINFO_IOCTL and the line change notifier.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Stable-dep-of: ee0166b637 ("gpiolib: cdev: fix uninitialised kfifo")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 02f6b0e1ec ]
The use-after-free issue occurs as follows: when the GPIO chip device file
is being closed by invoking gpio_chrdev_release(), watched_lines is freed
by bitmap_free(), but the unregistration of lineinfo_changed_nb notifier
chain failed due to waiting write rwsem. Additionally, one of the GPIO
chip's lines is also in the release process and holds the notifier chain's
read rwsem. Consequently, a race condition leads to the use-after-free of
watched_lines.
Here is the typical stack when issue happened:
[free]
gpio_chrdev_release()
--> bitmap_free(cdev->watched_lines) <-- freed
--> blocking_notifier_chain_unregister()
--> down_write(&nh->rwsem) <-- waiting rwsem
--> __down_write_common()
--> rwsem_down_write_slowpath()
--> schedule_preempt_disabled()
--> schedule()
[use]
st54spi_gpio_dev_release()
--> gpio_free()
--> gpiod_free()
--> gpiod_free_commit()
--> gpiod_line_state_notify()
--> blocking_notifier_call_chain()
--> down_read(&nh->rwsem); <-- held rwsem
--> notifier_call_chain()
--> lineinfo_changed_notify()
--> test_bit(xxxx, cdev->watched_lines) <-- use after free
The side effect of the use-after-free issue is that a GPIO line event is
being generated for userspace where it shouldn't. However, since the chrdev
is being closed, userspace won't have the chance to read that event anyway.
To fix the issue, call the bitmap_free() function after the unregistration
of lineinfo_changed_nb notifier chain.
Fixes: 51c1064e82 ("gpiolib: add new ioctl() for monitoring changes in line info")
Signed-off-by: Zhongqiu Han <quic_zhonhan@quicinc.com>
Link: https://lore.kernel.org/r/20240505141156.2944912-1-quic_zhonhan@quicinc.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 11baa36d31 ]
Add MODULE_DEVICE_TABLE(), so the module could be properly autoloaded
based on the alias from of_device_id table.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ace0ebe5c9 ]
The GPIO library expects the drivers to return -ENOTSUPP in some
cases and not using analogue POSIX code. Make the driver to follow
this.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d806f474a9 ]
The controller has several register bits describing access control
information for a given GPIO pin. When SCR_SEC_[R|W]EN is unset, it
means we have full read/write access to all the registers for given GPIO
pin. When SCR_SEC[R|W]EN is set, it means we need to further check the
accompanying SCR_SEC_G1[R|W] bit to determine read/write access to all
the registers for given GPIO pin.
This check was previously declaring that a GPIO pin was accessible
only if either of the following conditions were met:
- SCR_SEC_REN + SCR_SEC_WEN both set
or
- SCR_SEC_REN + SCR_SEC_WEN both set and
SCR_SEC_G1R + SCR_SEC_G1W both set
Update the check to properly handle cases where only one of
SCR_SEC_REN or SCR_SEC_WEN is set.
Fixes: b2b56a1632 ("gpio: tegra186: Check GPIO pin permission before access.")
Signed-off-by: Prathamesh Shete <pshete@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20240424095514.24397-1-pshete@nvidia.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7d045025a2 ]
IRQ chip data contains a pointer to the GPIO chip. Luckily we have
the pointers the same, but strictly speaking it's not guaranteed.
Even though, still better to fix this.
Fixes: ccf6fd6dcc ("gpio: merrifield: Introduce GPIO driver to support Merrifield")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
