diff mbox series

[v5,3/4] lib/test_kasan.c: add workqueue test case

Message ID 20201203022748.30681-1-walter-zh.wu@mediatek.com (mailing list archive)
State New, archived
Headers show
Series kasan: add workqueue stack for generic KASAN | expand

Commit Message

Walter Wu Dec. 3, 2020, 2:27 a.m. UTC
Adds a test to verify workqueue stack recording and print it in
KASAN report.

The KASAN report was as follows(cleaned up slightly):

 BUG: KASAN: use-after-free in kasan_workqueue_uaf

 Freed by task 54:
  kasan_save_stack+0x24/0x50
  kasan_set_track+0x24/0x38
  kasan_set_free_info+0x20/0x40
  __kasan_slab_free+0x10c/0x170
  kasan_slab_free+0x10/0x18
  kfree+0x98/0x270
  kasan_workqueue_work+0xc/0x18

 Last potentially related work creation:
  kasan_save_stack+0x24/0x50
  kasan_record_wq_stack+0xa8/0xb8
  insert_work+0x48/0x288
  __queue_work+0x3e8/0xc40
  queue_work_on+0xf4/0x118
  kasan_workqueue_uaf+0xfc/0x190

Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com>
Acked-by: Marco Elver <elver@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
---

v4:
- testcase has merge conflict, so that rebase onto the KASAN-KUNIT

---
 lib/test_kasan_module.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

Comments

Marco Elver Dec. 3, 2020, 10:29 a.m. UTC | #1
On Thu, 3 Dec 2020 at 03:27, Walter Wu <walter-zh.wu@mediatek.com> wrote:
>
> Adds a test to verify workqueue stack recording and print it in
> KASAN report.
>
> The KASAN report was as follows(cleaned up slightly):
>
>  BUG: KASAN: use-after-free in kasan_workqueue_uaf
>
>  Freed by task 54:
>   kasan_save_stack+0x24/0x50
>   kasan_set_track+0x24/0x38
>   kasan_set_free_info+0x20/0x40
>   __kasan_slab_free+0x10c/0x170
>   kasan_slab_free+0x10/0x18
>   kfree+0x98/0x270
>   kasan_workqueue_work+0xc/0x18
>
>  Last potentially related work creation:
>   kasan_save_stack+0x24/0x50
>   kasan_record_wq_stack+0xa8/0xb8
>   insert_work+0x48/0x288
>   __queue_work+0x3e8/0xc40
>   queue_work_on+0xf4/0x118
>   kasan_workqueue_uaf+0xfc/0x190
>
> Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com>
> Acked-by: Marco Elver <elver@google.com>
> Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
> Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
> Cc: Alexander Potapenko <glider@google.com>
> Cc: Matthias Brugger <matthias.bgg@gmail.com>
> ---
>
> v4:
> - testcase has merge conflict, so that rebase onto the KASAN-KUNIT
>
> ---
>  lib/test_kasan_module.c | 29 +++++++++++++++++++++++++++++
>  1 file changed, 29 insertions(+)
>
> diff --git a/lib/test_kasan_module.c b/lib/test_kasan_module.c
> index 2d68db6ae67b..62a87854b120 100644
> --- a/lib/test_kasan_module.c
> +++ b/lib/test_kasan_module.c
> @@ -91,6 +91,34 @@ static noinline void __init kasan_rcu_uaf(void)
>         call_rcu(&global_rcu_ptr->rcu, kasan_rcu_reclaim);
>  }
>
> +static noinline void __init kasan_workqueue_work(struct work_struct *work)
> +{
> +       kfree(work);
> +}
> +
> +static noinline void __init kasan_workqueue_uaf(void)
> +{
> +       struct workqueue_struct *workqueue;
> +       struct work_struct *work;
> +
> +       workqueue = create_workqueue("kasan_wq_test");
> +       if (!workqueue) {
> +               pr_err("Allocation failed\n");
> +               return;
> +       }
> +       work = kmalloc(sizeof(struct work_struct), GFP_KERNEL);
> +       if (!work) {
> +               pr_err("Allocation failed\n");
> +               return;
> +       }
> +
> +       INIT_WORK(work, kasan_workqueue_work);
> +       queue_work(workqueue, work);
> +       destroy_workqueue(workqueue);
> +
> +       pr_info("use-after-free on workqueue\n");
> +       ((volatile struct work_struct *)work)->data;
> +}
>
>  static int __init test_kasan_module_init(void)
>  {
> @@ -102,6 +130,7 @@ static int __init test_kasan_module_init(void)
>
>         copy_user_test();
>         kasan_rcu_uaf();
> +       kasan_workqueue_uaf();


Why can't this go into the KUnit based KASAN test?
Walter Wu Dec. 4, 2020, 1:32 a.m. UTC | #2
On Thu, 2020-12-03 at 11:29 +0100, Marco Elver wrote:
> On Thu, 3 Dec 2020 at 03:27, Walter Wu <walter-zh.wu@mediatek.com> wrote:
> >
> > Adds a test to verify workqueue stack recording and print it in
> > KASAN report.
> >
> > The KASAN report was as follows(cleaned up slightly):
> >
> >  BUG: KASAN: use-after-free in kasan_workqueue_uaf
> >
> >  Freed by task 54:
> >   kasan_save_stack+0x24/0x50
> >   kasan_set_track+0x24/0x38
> >   kasan_set_free_info+0x20/0x40
> >   __kasan_slab_free+0x10c/0x170
> >   kasan_slab_free+0x10/0x18
> >   kfree+0x98/0x270
> >   kasan_workqueue_work+0xc/0x18
> >
> >  Last potentially related work creation:
> >   kasan_save_stack+0x24/0x50
> >   kasan_record_wq_stack+0xa8/0xb8
> >   insert_work+0x48/0x288
> >   __queue_work+0x3e8/0xc40
> >   queue_work_on+0xf4/0x118
> >   kasan_workqueue_uaf+0xfc/0x190
> >
> > Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com>
> > Acked-by: Marco Elver <elver@google.com>
> > Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
> > Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
> > Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
> > Cc: Alexander Potapenko <glider@google.com>
> > Cc: Matthias Brugger <matthias.bgg@gmail.com>
> > ---
> >
> > v4:
> > - testcase has merge conflict, so that rebase onto the KASAN-KUNIT
> >
> > ---
> >  lib/test_kasan_module.c | 29 +++++++++++++++++++++++++++++
> >  1 file changed, 29 insertions(+)
> >
> > diff --git a/lib/test_kasan_module.c b/lib/test_kasan_module.c
> > index 2d68db6ae67b..62a87854b120 100644
> > --- a/lib/test_kasan_module.c
> > +++ b/lib/test_kasan_module.c
> > @@ -91,6 +91,34 @@ static noinline void __init kasan_rcu_uaf(void)
> >         call_rcu(&global_rcu_ptr->rcu, kasan_rcu_reclaim);
> >  }
> >
> > +static noinline void __init kasan_workqueue_work(struct work_struct *work)
> > +{
> > +       kfree(work);
> > +}
> > +
> > +static noinline void __init kasan_workqueue_uaf(void)
> > +{
> > +       struct workqueue_struct *workqueue;
> > +       struct work_struct *work;
> > +
> > +       workqueue = create_workqueue("kasan_wq_test");
> > +       if (!workqueue) {
> > +               pr_err("Allocation failed\n");
> > +               return;
> > +       }
> > +       work = kmalloc(sizeof(struct work_struct), GFP_KERNEL);
> > +       if (!work) {
> > +               pr_err("Allocation failed\n");
> > +               return;
> > +       }
> > +
> > +       INIT_WORK(work, kasan_workqueue_work);
> > +       queue_work(workqueue, work);
> > +       destroy_workqueue(workqueue);
> > +
> > +       pr_info("use-after-free on workqueue\n");
> > +       ((volatile struct work_struct *)work)->data;
> > +}
> >
> >  static int __init test_kasan_module_init(void)
> >  {
> > @@ -102,6 +130,7 @@ static int __init test_kasan_module_init(void)
> >
> >         copy_user_test();
> >         kasan_rcu_uaf();
> > +       kasan_workqueue_uaf();
> 
> 
> Why can't this go into the KUnit based KASAN test?

This test case has not been ported to KUnit, because KUnit's expect
failure will not check whether the work stack is exist. So it remains in
test_kasan_module, it is the same with kasan_rcu_uaf()[1].

[1]https://lkml.org/lkml/2020/8/1/45

Thanks.
Walter
diff mbox series

Patch

diff --git a/lib/test_kasan_module.c b/lib/test_kasan_module.c
index 2d68db6ae67b..62a87854b120 100644
--- a/lib/test_kasan_module.c
+++ b/lib/test_kasan_module.c
@@ -91,6 +91,34 @@  static noinline void __init kasan_rcu_uaf(void)
 	call_rcu(&global_rcu_ptr->rcu, kasan_rcu_reclaim);
 }
 
+static noinline void __init kasan_workqueue_work(struct work_struct *work)
+{
+	kfree(work);
+}
+
+static noinline void __init kasan_workqueue_uaf(void)
+{
+	struct workqueue_struct *workqueue;
+	struct work_struct *work;
+
+	workqueue = create_workqueue("kasan_wq_test");
+	if (!workqueue) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+	work = kmalloc(sizeof(struct work_struct), GFP_KERNEL);
+	if (!work) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	INIT_WORK(work, kasan_workqueue_work);
+	queue_work(workqueue, work);
+	destroy_workqueue(workqueue);
+
+	pr_info("use-after-free on workqueue\n");
+	((volatile struct work_struct *)work)->data;
+}
 
 static int __init test_kasan_module_init(void)
 {
@@ -102,6 +130,7 @@  static int __init test_kasan_module_init(void)
 
 	copy_user_test();
 	kasan_rcu_uaf();
+	kasan_workqueue_uaf();
 
 	kasan_restore_multi_shot(multishot);
 	return -EAGAIN;