Thanks Colin, good catch.
Enric, could you squash this into the real commit?
On Tue, Jun 18, 2019 at 9:39 AM Colin King <colin.king@xxxxxxxxxxxxx> wrote:
>
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> If the kzalloc of the entries queue q fails a null pointer dereference
> occurs when accessing q->capacity and q->lock. Add a kzalloc failure
> check and handle the null return case in the calling function
> event_device_add.
>
> Addresses-Coverity: ("Dereference null return")
> Fixes: 75589e37d1dc ("platform/chrome: wilco_ec: Add circular buffer as event queue")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
> drivers/platform/chrome/wilco_ec/event.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/platform/chrome/wilco_ec/event.c b/drivers/platform/chrome/wilco_ec/event.c
> index c975b76e6255..e251a989b152 100644
> --- a/drivers/platform/chrome/wilco_ec/event.c
> +++ b/drivers/platform/chrome/wilco_ec/event.c
> @@ -112,8 +112,11 @@ module_param(queue_size, int, 0644);
> static struct ec_event_queue *event_queue_new(int capacity)
> {
> size_t entries_size = sizeof(struct ec_event *) * capacity;
> - struct ec_event_queue *q = kzalloc(sizeof(*q) + entries_size,
> - GFP_KERNEL);
> + struct ec_event_queue *q;
> +
> + q = kzalloc(sizeof(*q) + entries_size, GFP_KERNEL);
> + if (!q)
> + return NULL;
>
> q->capacity = capacity;
> spin_lock_init(&q->lock);
> @@ -474,6 +477,11 @@ static int event_device_add(struct acpi_device *adev)
> /* Initialize the device data. */
> adev->driver_data = dev_data;
> dev_data->events = event_queue_new(queue_size);
> + if (!dev_data->events) {
> + kfree(dev_data);
> + error = -ENOMEM;
> + goto free_minor;
> + }
> init_waitqueue_head(&dev_data->wq);
> dev_data->exist = true;
> atomic_set(&dev_data->available, 1);
Signed-off-by: Nick Crews <ncrews@xxxxxxxxxxxx>
> --
> 2.20.1
>
