Re: [PATCH 04/11] kasan: add match-all tag tests

From: Andrey Konovalov
Date: Tue Jan 12 2021 - 13:11:02 EST


On Tue, Jan 12, 2021 at 9:05 AM Alexander Potapenko <glider@xxxxxxxxxx> wrote:
>
> On Tue, Jan 5, 2021 at 7:28 PM Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote:
> >
> > Add 3 new tests for tag-based KASAN modes:
> >
> > 1. Check that match-all pointer tag is not assigned randomly.
> > 2. Check that 0xff works as a match-all pointer tag.
> > 3. Check that there are no match-all memory tags.
> >
> > Note, that test #3 causes a significant number (255) of KASAN reports
> > to be printed during execution for the SW_TAGS mode.
> >
> > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
> > Link: https://linux-review.googlesource.com/id/I78f1375efafa162b37f3abcb2c5bc2f3955dfd8e
> > ---
> > lib/test_kasan.c | 93 ++++++++++++++++++++++++++++++++++++++++++++++++
> > mm/kasan/kasan.h | 6 ++++
> > 2 files changed, 99 insertions(+)
> >
> > diff --git a/lib/test_kasan.c b/lib/test_kasan.c
> > index 46e578c8e842..f1eda0bcc780 100644
> > --- a/lib/test_kasan.c
> > +++ b/lib/test_kasan.c
> > @@ -13,6 +13,7 @@
> > #include <linux/mman.h>
> > #include <linux/module.h>
> > #include <linux/printk.h>
> > +#include <linux/random.h>
> > #include <linux/slab.h>
> > #include <linux/string.h>
> > #include <linux/uaccess.h>
> > @@ -790,6 +791,95 @@ static void vmalloc_oob(struct kunit *test)
> > vfree(area);
> > }
> >
> > +/*
> > + * Check that match-all pointer tag is not assigned randomly for
> > + * tag-based modes.
> > + */
> > +static void match_all_not_assigned(struct kunit *test)
> > +{
>
> Do we want to run this test in non-tag-based modes? Probably not?

Will fix in v2, thanks!