Commit Graph

6 Commits

Author SHA1 Message Date
Thomas Gleixner 80503b23b2 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 149
Based on 1 normalized pattern(s):

  licensed under the gpl 2 or later

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 82 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190524100845.150836982@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:25:18 -07:00
Lars-Peter Clausen f027e0b3a7 iio: adis_lib: Initialize trigger before requesting interrupt
The adis_probe_trigger() creates a new IIO trigger and requests an
interrupt associated with the trigger. The interrupt uses the generic
iio_trigger_generic_data_rdy_poll() function as its interrupt handler.

Currently the driver initializes some fields of the trigger structure after
the interrupt has been requested. But an interrupt can fire as soon as it
has been requested. This opens up a race condition.

iio_trigger_generic_data_rdy_poll() will access the trigger data structure
and dereference the ops field. If the ops field is not yet initialized this
will result in a NULL pointer deref.

It is not expected that the device generates an interrupt at this point, so
typically this issue did not surface unless e.g. due to a hardware
misconfiguration (wrong interrupt number, wrong polarity, etc.).

But some newer devices from the ADIS family start to generate periodic
interrupts in their power-on reset configuration and unfortunately the
interrupt can not be masked in the device.  This makes the race condition
much more visible and the following crash has been observed occasionally
when booting a system using the ADIS16460.

	Unable to handle kernel NULL pointer dereference at virtual address 00000008
	pgd = c0004000
	[00000008] *pgd=00000000
	Internal error: Oops: 5 [#1] PREEMPT SMP ARM
	Modules linked in:
	CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.9.0-04126-gf9739f0-dirty #257
	Hardware name: Xilinx Zynq Platform
	task: ef04f640 task.stack: ef050000
	PC is at iio_trigger_notify_done+0x30/0x68
	LR is at iio_trigger_generic_data_rdy_poll+0x18/0x20
	pc : [<c042d868>]    lr : [<c042d924>]    psr: 60000193
	sp : ef051bb8  ip : 00000000  fp : ef106400
	r10: c081d80a  r9 : ef3bfa00  r8 : 00000087
	r7 : ef051bec  r6 : 00000000  r5 : ef3bfa00  r4 : ee92ab00
	r3 : 00000000  r2 : 00000000  r1 : 00000000  r0 : ee97e400
	Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment none
	Control: 18c5387d  Table: 0000404a  DAC: 00000051
	Process swapper/0 (pid: 1, stack limit = 0xef050210)
	[<c042d868>] (iio_trigger_notify_done) from [<c0065b10>] (__handle_irq_event_percpu+0x88/0x118)
	[<c0065b10>] (__handle_irq_event_percpu) from [<c0065bbc>] (handle_irq_event_percpu+0x1c/0x58)
	[<c0065bbc>] (handle_irq_event_percpu) from [<c0065c30>] (handle_irq_event+0x38/0x5c)
	[<c0065c30>] (handle_irq_event) from [<c0068e28>] (handle_level_irq+0xa4/0x130)
	[<c0068e28>] (handle_level_irq) from [<c0064e74>] (generic_handle_irq+0x24/0x34)
	[<c0064e74>] (generic_handle_irq) from [<c021ab7c>] (zynq_gpio_irqhandler+0xb8/0x13c)
	[<c021ab7c>] (zynq_gpio_irqhandler) from [<c0064e74>] (generic_handle_irq+0x24/0x34)
	[<c0064e74>] (generic_handle_irq) from [<c0065370>] (__handle_domain_irq+0x5c/0xb4)
	[<c0065370>] (__handle_domain_irq) from [<c000940c>] (gic_handle_irq+0x48/0x8c)
	[<c000940c>] (gic_handle_irq) from [<c0013e8c>] (__irq_svc+0x6c/0xa8)

To fix this make sure that the trigger is fully initialized before
requesting the interrupt.

Fixes: ccd2b52f4a ("staging:iio: Add common ADIS library")
Reported-by: Robin Getz <Robin.Getz@analog.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-02-17 14:16:35 +00:00
Jonathan Cameron 79978a9bd0 iio:imu: drop assign iio_info.driver_module and iio_trigger_ops.owner
The equivalent of both of these are now done via macro magic when
the relevant register calls are made.  The actual structure
elements will shortly go away.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
2017-08-22 21:31:01 +01:00
Darshana Padmadas 4ce7ca89d6 iio: imu: Use iio_trigger_get for indio_dev->trig assignment
This patch uses iio_trigger_get to increment the reference
count of trigger device, to avoid incorrect assignment.
Can result in a null pointer dereference during removal if the
trigger has been changed before removal.

This patch refers to a similar situation encountered through the
following discussion:
http://www.spinics.net/lists/linux-iio/msg13669.html

Signed-off-by: Darshana Padmadas <darshanapadmadas@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-03-28 13:51:40 +00:00
Lars-Peter Clausen 1e9663c62b iio:trigger: Introduce iio_tigger_{set,get}_drvdata
Introduce iio_tigger_{set,get}_drvdata which allows to attach driver specific
data to a trigger. The functions wrap access to the triggers private_data field
and all current users are updated to use iio_tigger_{set,get}_drvdata instead of
directly accessing the private_data field. This is the first step towards
removing the private_data field from the iio_trigger struct.

The following coccinelle script has been used to update the drivers:
<smpl>
@@
struct iio_trigger *trigger;
expression priv;
@@
-trigger->private_data = priv
+iio_trigger_set_drv_data(trigger, priv)

@@
struct iio_trigger *trigger;
@@
-trigger->private_data
+iio_trigger_get_drv_data(trigger)
</smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-03-25 21:06:09 +00:00
Lars-Peter Clausen ec04cb048d staging:iio: Move adis library out of staging
Now that the adis library no longer depends on the sw_ring buffer implementation
we can move it out of staging.

While we are at it also sort the entries in the iio Kconfig and Makefile to be
in alphabetical order.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2012-11-19 22:22:12 +00:00