On Fri, Mar 18, 2022 at 2:50 AM David Gow <davidgow@xxxxxxxxxx> wrote: > > The kunit_remove_resource() function is used to unlink a resource from > the list of resources in the test, making it no longer show up in > kunit_find_resource(). > > However, this could lead to a race condition if two threads called > kunit_remove_resource() on the same resource at the same time: the > resource would be removed from the list twice (causing a crash at the > second list_del()), and the refcount for the resource would be > decremented twice (instead of once, for the reference held by the > resource list). > > Fix both problems, the first by using list_del_init(), and the second by > checking if the resource has already been removed using list_empty(), > and only decrementing its refcount if it has not. > > Also add a KUnit test for the kunit_remove_resource() function which > tests this behaviour. > > Reported-by: Daniel Latypov <dlatypov@xxxxxxxxxx> > Signed-off-by: David Gow <davidgow@xxxxxxxxxx> Reviewed-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
