diff options
author | Martin Fuzzey <mfuzzey@parkeon.com> | 2015-02-19 15:17:44 +0100 |
---|---|---|
committer | Jonathan Cameron <jic23@kernel.org> | 2015-03-14 18:54:14 +0000 |
commit | c1b03ab5e886760bdd38c9c7a27af149046ffe01 (patch) | |
tree | ad8d671b87c667e8eeb4e6ae97811132cecfddbe | |
parent | af5e1a68318e2ed2de22fc2d7a02f2882abe073c (diff) | |
download | linux-c1b03ab5e886760bdd38c9c7a27af149046ffe01.tar.bz2 |
iio: core: Fix double free.
When an error occurred during event registration memory was freed twice
resulting in kernel memory corruption and a crash in unrelated code.
The problem was caused by
iio_device_unregister_eventset()
iio_device_unregister_sysfs()
being called twice, once on the error path and then
again via iio_dev_release().
Fix this by making these two functions idempotent so they
may be called multiple times.
The problem was observed before applying
78b33216 iio:core: Handle error when mask type is not separate
Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
-rw-r--r-- | drivers/iio/industrialio-core.c | 5 | ||||
-rw-r--r-- | drivers/iio/industrialio-event.c | 1 |
2 files changed, 4 insertions, 2 deletions
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index aaba9d3d980e..4df97f650e44 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -847,8 +847,7 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev, * @attr_list: List of IIO device attributes * * This function frees the memory allocated for each of the IIO device - * attributes in the list. Note: if you want to reuse the list after calling - * this function you have to reinitialize it using INIT_LIST_HEAD(). + * attributes in the list. */ void iio_free_chan_devattr_list(struct list_head *attr_list) { @@ -856,6 +855,7 @@ void iio_free_chan_devattr_list(struct list_head *attr_list) list_for_each_entry_safe(p, n, attr_list, l) { kfree(p->dev_attr.attr.name); + list_del(&p->l); kfree(p); } } @@ -936,6 +936,7 @@ static void iio_device_unregister_sysfs(struct iio_dev *indio_dev) iio_free_chan_devattr_list(&indio_dev->channel_attr_list); kfree(indio_dev->chan_attr_group.attrs); + indio_dev->chan_attr_group.attrs = NULL; } static void iio_dev_release(struct device *device) diff --git a/drivers/iio/industrialio-event.c b/drivers/iio/industrialio-event.c index a4b397048f71..a99692ba91bc 100644 --- a/drivers/iio/industrialio-event.c +++ b/drivers/iio/industrialio-event.c @@ -500,6 +500,7 @@ int iio_device_register_eventset(struct iio_dev *indio_dev) error_free_setup_event_lines: iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list); kfree(indio_dev->event_interface); + indio_dev->event_interface = NULL; return ret; } |