drbd: poison free'd device, resource and connection structs

Now that we have additional asynchronous kref_get/kref_put
via debugfs, make sure we catch access after free.

Poison struct drbd_device, drbd_connection and drbd_resource
before kfree() with 0xfd, 0xfc, and 0xf2, respectively.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit is contained in:
Lars Ellenberg 2014-05-14 21:35:21 +02:00 committed by Philipp Reisner
parent 45d2933c92
commit c2258ffc56

View File

@ -2192,6 +2192,7 @@ void drbd_destroy_device(struct kref *kref)
blk_cleanup_queue(device->rq_queue);
kfree(device->rs_plan_s);
kfree(first_peer_device(device));
memset(device, 0xfd, sizeof(*device));
kfree(device);
for_each_connection(connection, resource)
@ -2285,6 +2286,7 @@ void drbd_destroy_resource(struct kref *kref)
idr_destroy(&resource->devices);
free_cpumask_var(resource->cpu_mask);
kfree(resource->name);
memset(resource, 0xf2, sizeof(*resource));
kfree(resource);
}
@ -2665,6 +2667,7 @@ void drbd_destroy_connection(struct kref *kref)
drbd_free_socket(&connection->data);
kfree(connection->int_dig_in);
kfree(connection->int_dig_vv);
memset(connection, 0xfc, sizeof(*connection));
kfree(connection);
kref_put(&resource->kref, drbd_destroy_resource);
}