This is a note to let you know that I've just added the patch titled

iio: trigger: free trigger resource correctly

to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: iio-trigger-free-trigger-resource-correctly.patch and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Thu Nov 9 18:22:51 CET 2017

From: Alison Schofield amsfield22@gmail.com Date: Thu, 19 Jan 2017 19:47:38 -0800 Subject: iio: trigger: free trigger resource correctly

From: Alison Schofield amsfield22@gmail.com

[ Upstream commit 10e840dfb0b7fc345082dd9e5fff3c1c02e7690e ]

These stand-alone trigger drivers were using iio_trigger_put() where they should have been using iio_trigger_free(). The iio_trigger_put() adds a module_put which is bad since they never did a module_get.

In the sysfs driver, module_get/put's are used as triggers are added & removed. This extra module_put() occurs on an error path in the probe routine (probably rare).

In the bfin-timer & interrupt trigger drivers, the module resources are not explicitly managed, so it's doing a put on something that was never get'd. It occurs on the probe error path and on the remove path (not so rare).

Tested with the sysfs trigger driver. The bfin & interrupt drivers were build tested & inspected only.

Signed-off-by: Alison Schofield amsfield22@gmail.com Signed-off-by: Jonathan Cameron jic23@kernel.org Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iio/trigger/iio-trig-interrupt.c | 8 ++++---- drivers/iio/trigger/iio-trig-sysfs.c | 2 +- drivers/staging/iio/trigger/iio-trig-bfin-timer.c | 4 ++-- 3 files changed, 7 insertions(+), 7 deletions(-)

--- a/drivers/iio/trigger/iio-trig-interrupt.c +++ b/drivers/iio/trigger/iio-trig-interrupt.c @@ -58,7 +58,7 @@ static int iio_interrupt_trigger_probe(s trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL); if (!trig_info) { ret = -ENOMEM; - goto error_put_trigger; + goto error_free_trigger; } iio_trigger_set_drvdata(trig, trig_info); trig_info->irq = irq; @@ -83,8 +83,8 @@ error_release_irq: free_irq(irq, trig); error_free_trig_info: kfree(trig_info); -error_put_trigger: - iio_trigger_put(trig); +error_free_trigger: + iio_trigger_free(trig); error_ret: return ret; } @@ -99,7 +99,7 @@ static int iio_interrupt_trigger_remove( iio_trigger_unregister(trig); free_irq(trig_info->irq, trig); kfree(trig_info); - iio_trigger_put(trig); + iio_trigger_free(trig);

return 0; } --- a/drivers/iio/trigger/iio-trig-sysfs.c +++ b/drivers/iio/trigger/iio-trig-sysfs.c @@ -174,7 +174,7 @@ static int iio_sysfs_trigger_probe(int i return 0;

out2: - iio_trigger_put(t->trig); + iio_trigger_free(t->trig); free_t: kfree(t); out1: --- a/drivers/staging/iio/trigger/iio-trig-bfin-timer.c +++ b/drivers/staging/iio/trigger/iio-trig-bfin-timer.c @@ -259,7 +259,7 @@ out_free_irq: out1: iio_trigger_unregister(st->trig); out: - iio_trigger_put(st->trig); + iio_trigger_free(st->trig); return ret; }

@@ -272,7 +272,7 @@ static int iio_bfin_tmr_trigger_remove(s peripheral_free(st->t->pin); free_irq(st->irq, st); iio_trigger_unregister(st->trig); - iio_trigger_put(st->trig); + iio_trigger_free(st->trig);

return 0; }

Patches currently in stable-queue which might be from amsfield22@gmail.com are

queue-4.4/iio-trigger-free-trigger-resource-correctly.patch