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* [PATCH] lib: test_ubsan: VLA no longer used in kernel
@ 2019-01-13 18:32 Olof Johansson
  2019-01-14  0:16 ` Kees Cook
  2019-01-14  6:47 ` Dmitry Vyukov
  0 siblings, 2 replies; 3+ messages in thread
From: Olof Johansson @ 2019-01-13 18:32 UTC (permalink / raw)
  To: akpm
  Cc: jinb.park7, colin.king, linux-kernel, Olof Johansson,
	Andrey Ryabinin, Dmitry Vyukov, Kees Cook

Since we now build with -Wvla, any use of VLA throws a warning.
Including this test, so... maybe we should just remove the test?

lib/test_ubsan.c: In function 'test_ubsan_vla_bound_not_positive':
lib/test_ubsan.c:48:2: warning: ISO C90 forbids variable length array 'buf' [-Wvla]

For the out-of-bounds test, switch to non-VLA setup.

lib/test_ubsan.c: In function 'test_ubsan_out_of_bounds':
lib/test_ubsan.c:64:2: warning: ISO C90 forbids variable length array 'arr' [-Wvla]

Cc: Colin Ian King <colin.king@canonical.com>
Cc: Jinbum Park <jinb.park7@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

---
 lib/test_ubsan.c | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/lib/test_ubsan.c b/lib/test_ubsan.c
index 280f4979d00ed..9ea10adf7a66f 100644
--- a/lib/test_ubsan.c
+++ b/lib/test_ubsan.c
@@ -42,14 +42,6 @@ static void test_ubsan_divrem_overflow(void)
 	val /= val2;
 }
 
-static void test_ubsan_vla_bound_not_positive(void)
-{
-	volatile int size = -1;
-	char buf[size];
-
-	(void)buf;
-}
-
 static void test_ubsan_shift_out_of_bounds(void)
 {
 	volatile int val = -1;
@@ -61,7 +53,7 @@ static void test_ubsan_shift_out_of_bounds(void)
 static void test_ubsan_out_of_bounds(void)
 {
 	volatile int i = 4, j = 5;
-	volatile int arr[i];
+	volatile int arr[4];
 
 	arr[j] = i;
 }
@@ -113,7 +105,6 @@ static const test_ubsan_fp test_ubsan_array[] = {
 	test_ubsan_mul_overflow,
 	test_ubsan_negate_overflow,
 	test_ubsan_divrem_overflow,
-	test_ubsan_vla_bound_not_positive,
 	test_ubsan_shift_out_of_bounds,
 	test_ubsan_out_of_bounds,
 	test_ubsan_load_invalid_value,
-- 
2.11.0


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] lib: test_ubsan: VLA no longer used in kernel
  2019-01-13 18:32 [PATCH] lib: test_ubsan: VLA no longer used in kernel Olof Johansson
@ 2019-01-14  0:16 ` Kees Cook
  2019-01-14  6:47 ` Dmitry Vyukov
  1 sibling, 0 replies; 3+ messages in thread
From: Kees Cook @ 2019-01-14  0:16 UTC (permalink / raw)
  To: Olof Johansson
  Cc: Andrew Morton, Jinbum Park, Colin King, LKML, Andrey Ryabinin,
	Dmitry Vyukov

On Sun, Jan 13, 2019 at 10:32 AM Olof Johansson <olof@lixom.net> wrote:
>
> Since we now build with -Wvla, any use of VLA throws a warning.
> Including this test, so... maybe we should just remove the test?
>
> lib/test_ubsan.c: In function 'test_ubsan_vla_bound_not_positive':
> lib/test_ubsan.c:48:2: warning: ISO C90 forbids variable length array 'buf' [-Wvla]

I patched the Makefile to remove -Wvla for the *SAN tests. Something
recently seems to be stripping it from the build command line, though.
I haven't figured out what's going on...

-Kees

>
> For the out-of-bounds test, switch to non-VLA setup.
>
> lib/test_ubsan.c: In function 'test_ubsan_out_of_bounds':
> lib/test_ubsan.c:64:2: warning: ISO C90 forbids variable length array 'arr' [-Wvla]
>
> Cc: Colin Ian King <colin.king@canonical.com>
> Cc: Jinbum Park <jinb.park7@gmail.com>
> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
> Cc: Dmitry Vyukov <dvyukov@google.com>
> Cc: Kees Cook <keescook@chromium.org>
> Signed-off-by: Olof Johansson <olof@lixom.net>
>
> ---
>  lib/test_ubsan.c | 11 +----------
>  1 file changed, 1 insertion(+), 10 deletions(-)
>
> diff --git a/lib/test_ubsan.c b/lib/test_ubsan.c
> index 280f4979d00ed..9ea10adf7a66f 100644
> --- a/lib/test_ubsan.c
> +++ b/lib/test_ubsan.c
> @@ -42,14 +42,6 @@ static void test_ubsan_divrem_overflow(void)
>         val /= val2;
>  }
>
> -static void test_ubsan_vla_bound_not_positive(void)
> -{
> -       volatile int size = -1;
> -       char buf[size];
> -
> -       (void)buf;
> -}
> -
>  static void test_ubsan_shift_out_of_bounds(void)
>  {
>         volatile int val = -1;
> @@ -61,7 +53,7 @@ static void test_ubsan_shift_out_of_bounds(void)
>  static void test_ubsan_out_of_bounds(void)
>  {
>         volatile int i = 4, j = 5;
> -       volatile int arr[i];
> +       volatile int arr[4];
>
>         arr[j] = i;
>  }
> @@ -113,7 +105,6 @@ static const test_ubsan_fp test_ubsan_array[] = {
>         test_ubsan_mul_overflow,
>         test_ubsan_negate_overflow,
>         test_ubsan_divrem_overflow,
> -       test_ubsan_vla_bound_not_positive,
>         test_ubsan_shift_out_of_bounds,
>         test_ubsan_out_of_bounds,
>         test_ubsan_load_invalid_value,
> --
> 2.11.0
>


-- 
Kees Cook

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] lib: test_ubsan: VLA no longer used in kernel
  2019-01-13 18:32 [PATCH] lib: test_ubsan: VLA no longer used in kernel Olof Johansson
  2019-01-14  0:16 ` Kees Cook
@ 2019-01-14  6:47 ` Dmitry Vyukov
  1 sibling, 0 replies; 3+ messages in thread
From: Dmitry Vyukov @ 2019-01-14  6:47 UTC (permalink / raw)
  To: Olof Johansson
  Cc: Andrew Morton, Jinbum Park, Colin King, LKML, Andrey Ryabinin, Kees Cook

On Sun, Jan 13, 2019 at 7:32 PM Olof Johansson <olof@lixom.net> wrote:
>
> Since we now build with -Wvla, any use of VLA throws a warning.
> Including this test, so... maybe we should just remove the test?
>
> lib/test_ubsan.c: In function 'test_ubsan_vla_bound_not_positive':
> lib/test_ubsan.c:48:2: warning: ISO C90 forbids variable length array 'buf' [-Wvla]
>
> For the out-of-bounds test, switch to non-VLA setup.
>
> lib/test_ubsan.c: In function 'test_ubsan_out_of_bounds':
> lib/test_ubsan.c:64:2: warning: ISO C90 forbids variable length array 'arr' [-Wvla]
>
> Cc: Colin Ian King <colin.king@canonical.com>
> Cc: Jinbum Park <jinb.park7@gmail.com>
> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
> Cc: Dmitry Vyukov <dvyukov@google.com>
> Cc: Kees Cook <keescook@chromium.org>
> Signed-off-by: Olof Johansson <olof@lixom.net>

Acked-by: Dmitry Vyukov <dvyukov@google.com>

> ---
>  lib/test_ubsan.c | 11 +----------
>  1 file changed, 1 insertion(+), 10 deletions(-)
>
> diff --git a/lib/test_ubsan.c b/lib/test_ubsan.c
> index 280f4979d00ed..9ea10adf7a66f 100644
> --- a/lib/test_ubsan.c
> +++ b/lib/test_ubsan.c
> @@ -42,14 +42,6 @@ static void test_ubsan_divrem_overflow(void)
>         val /= val2;
>  }
>
> -static void test_ubsan_vla_bound_not_positive(void)
> -{
> -       volatile int size = -1;
> -       char buf[size];
> -
> -       (void)buf;
> -}
> -
>  static void test_ubsan_shift_out_of_bounds(void)
>  {
>         volatile int val = -1;
> @@ -61,7 +53,7 @@ static void test_ubsan_shift_out_of_bounds(void)
>  static void test_ubsan_out_of_bounds(void)
>  {
>         volatile int i = 4, j = 5;
> -       volatile int arr[i];
> +       volatile int arr[4];
>
>         arr[j] = i;
>  }
> @@ -113,7 +105,6 @@ static const test_ubsan_fp test_ubsan_array[] = {
>         test_ubsan_mul_overflow,
>         test_ubsan_negate_overflow,
>         test_ubsan_divrem_overflow,
> -       test_ubsan_vla_bound_not_positive,
>         test_ubsan_shift_out_of_bounds,
>         test_ubsan_out_of_bounds,
>         test_ubsan_load_invalid_value,
> --
> 2.11.0
>

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2019-01-14  6:47 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2019-01-13 18:32 [PATCH] lib: test_ubsan: VLA no longer used in kernel Olof Johansson
2019-01-14  0:16 ` Kees Cook
2019-01-14  6:47 ` Dmitry Vyukov

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