diff options
| author | Martin Fuzzey <mfuzzey@parkeon.com> | 2015-02-19 15:17:44 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-04-19 10:10:19 +0200 |
| commit | a8173cd017a912dd333f68bf1c0c31afaf70d4e3 (patch) | |
| tree | 7fcd767f8e7f218dba2ce8aaeaadb669b96c9296 | |
| parent | 6cf22b22f477fc59341d96f1d2a56f2b6f09b5e7 (diff) | |
iio: core: Fix double free.
commit c1b03ab5e886760bdd38c9c7a27af149046ffe01 upstream.
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>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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 af3e76d652ba..f009d053384a 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -832,8 +832,7 @@ 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) { @@ -841,6 +840,7 @@ 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); } } @@ -921,6 +921,7 @@ 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 0c1e37e3120a..35c02aeec75e 100644 --- a/drivers/iio/industrialio-event.c +++ b/drivers/iio/industrialio-event.c @@ -493,6 +493,7 @@ 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; } |