This is a note to let you know that I've just added the patch titled
iio: core: fix ioctl handlers removal
to the 5.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
iio-core-fix-ioctl-handlers-removal.patch
and it can be found in the queue-5.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 901f84de0e16bde10a72d7eb2f2eb73fcde8fa1a Mon Sep 17 00:00:00 2001
From: Tomasz Duszynski <tomasz.duszynski@xxxxxxxxxxx>
Date: Fri, 23 Apr 2021 10:02:44 +0200
Subject: iio: core: fix ioctl handlers removal
From: Tomasz Duszynski <tomasz.duszynski@xxxxxxxxxxx>
commit 901f84de0e16bde10a72d7eb2f2eb73fcde8fa1a upstream.
Currently ioctl handlers are removed twice. For the first time during
iio_device_unregister() then later on inside
iio_device_unregister_eventset() and iio_buffers_free_sysfs_and_mask().
Double free leads to kernel panic.
Fix this by not touching ioctl handlers list directly but rather
letting code responsible for registration call the matching cleanup
routine itself.
Fixes: 8dedcc3eee3ac ("iio: core: centralize ioctl() calls to the main chardev")
Signed-off-by: Tomasz Duszynski <tomasz.duszynski@xxxxxxxxxxx>
Acked-by: Alexandru Ardelean <ardeleanalex@xxxxxxxxx>
Cc: <Stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210423080244.2790-1-tomasz.duszynski@xxxxxxxxxxx
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/iio/industrialio-core.c | 6 ------
1 file changed, 6 deletions(-)
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -1863,9 +1863,6 @@ EXPORT_SYMBOL(__iio_device_register);
**/
void iio_device_unregister(struct iio_dev *indio_dev)
{
- struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
- struct iio_ioctl_handler *h, *t;
-
cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);
mutex_lock(&indio_dev->info_exist_lock);
@@ -1876,9 +1873,6 @@ void iio_device_unregister(struct iio_de
indio_dev->info = NULL;
- list_for_each_entry_safe(h, t, &iio_dev_opaque->ioctl_handlers, entry)
- list_del(&h->entry);
-
iio_device_wakeup_eventset(indio_dev);
iio_buffer_wakeup_poll(indio_dev);
Patches currently in stable-queue which might be from tomasz.duszynski@xxxxxxxxxxx are
queue-5.12/iio-core-fix-ioctl-handlers-removal.patch
