On Thu, Sep 9, 2021 at 12:26 AM 'Xiyu Yang' via KUnit Development <kunit-dev@xxxxxxxxxxxxxxxx> wrote: > > The reference counting issue happens in the normal path of > kfree_at_end(). When kunit_alloc_and_get_resource() is invoked, the > function forgets to handle the returned resource object, whose refcount > increased inside, causing a refcount leak. > > Fix this issue by calling kunit_alloc_resource() instead of > kunit_alloc_and_get_resource(). > > Signed-off-by: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx> > Signed-off-by: Xin Tan <tanxin.ctf@xxxxxxxxx> Reviewed-by: Daniel Latypov <dlatypov@xxxxxxxxxx> Ah, thanks for finding and fixing this! We really should have better documentation/otherwise make it clearer that people shouldn't use the "_and_get" version. I went and added some pr_info() calls to verify that these were being leaked before and they're fixed now. I copy-pasted this mistake into https://lore.kernel.org/linux-kselftest/20210831171926.3832806-2-dlatypov@xxxxxxxxxx/. I'll send a v3 fix for that patch as well. > --- > lib/kunit/executor_test.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lib/kunit/executor_test.c b/lib/kunit/executor_test.c > index cdbe54b16501..c2dcfb1f6e97 100644 > --- a/lib/kunit/executor_test.c > +++ b/lib/kunit/executor_test.c > @@ -116,7 +116,7 @@ static void kfree_at_end(struct kunit *test, const void *to_free) > /* kfree() handles NULL already, but avoid allocating a no-op cleanup. */ > if (IS_ERR_OR_NULL(to_free)) > return; > - kunit_alloc_and_get_resource(test, NULL, kfree_res_free, GFP_KERNEL, > + kunit_alloc_resource(test, NULL, kfree_res_free, GFP_KERNEL, > (void *)to_free); > } > > -- > 2.7.4 > > -- > You received this message because you are subscribed to the Google Groups "KUnit Development" group. > To unsubscribe from this group and stop receiving emails from it, send an email to kunit-dev+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/kunit-dev/1631172276-82914-1-git-send-email-xiyuyang19%40fudan.edu.cn.
