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 <[email protected]>
Signed-off-by: Xin Tan <[email protected]>
---
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
On Thu, Sep 9, 2021 at 12:26 AM 'Xiyu Yang' via KUnit Development
<[email protected]> 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 <[email protected]>
> Signed-off-by: Xin Tan <[email protected]>
Reviewed-by: Daniel Latypov <[email protected]>
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/[email protected]/.
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
>
> --
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> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
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On Thu, Sep 9, 2021 at 9:59 AM Daniel Latypov <[email protected]> wrote:
>
> On Thu, Sep 9, 2021 at 12:26 AM 'Xiyu Yang' via KUnit Development
> <[email protected]> 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 <[email protected]>
> > Signed-off-by: Xin Tan <[email protected]>
>
> Reviewed-by: Daniel Latypov <[email protected]>
>
> 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/[email protected]/.
> I'll send a v3 fix for that patch as well.
Fixed that patch:
https://lore.kernel.org/linux-kselftest/[email protected]/
I assume this patch and that one shouldn't have merge conflicts, so we
don't need these to be applied in any specific order.
>
> > ---
> > 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 [email protected].
> > 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.
On Thu, Sep 9, 2021 at 12:26 AM Xiyu Yang <[email protected]> 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 <[email protected]>
> Signed-off-by: Xin Tan <[email protected]>
Reviewed-by: Brendan Higgins <[email protected]>
Thanks!
On 9/28/21 3:27 PM, Brendan Higgins wrote:
> On Thu, Sep 9, 2021 at 12:26 AM Xiyu Yang <[email protected]> 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 <[email protected]>
>> Signed-off-by: Xin Tan <[email protected]>
>
> Reviewed-by: Brendan Higgins <[email protected]>
>
> Thanks!
>
Thank you for the fix.
Applied now after fixing a checkpatch alignment check to
git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git/
kunit-fixes branch.
Please remember to run checkpatch.pl before sending patches.
thanks,
-- Shuah