On Thu, Apr 2, 2020 at 10:46 PM 'Patricia Alfonso' via kasan-dev <kasan-dev@xxxxxxxxxxxxxxxx> wrote: > > Integrate KASAN into KUnit testing framework. > - Fail tests when KASAN reports an error that is not expected > - Use KUNIT_EXPECT_KASAN_FAIL to expect a KASAN error in KASAN > tests > - Expected KASAN reports pass tests and are still printed when run > without kunit_tool (kunit_tool still bypasses the report due to the > test passing) > - KUnit struct in current task used to keep track of the current > test from KASAN code > > Make use of "[PATCH v3 kunit-next 1/2] kunit: generalize > kunit_resource API beyond allocated resources" and "[PATCH v3 > kunit-next 2/2] kunit: add support for named resources" from Alan > Maguire [1] > - A named resource is added to a test when a KASAN report is > expected > - This resource contains a struct for kasan_data containing > booleans representing if a KASAN report is expected and if a > KASAN report is found > > [1] (https://lore.kernel.org/linux-kselftest/1583251361-12748-1-git-send-email-alan.maguire@xxxxxxxxxx/T/#t) > > Signed-off-by: Patricia Alfonso <trishalfonso@xxxxxxxxxx> > Reviewed-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> > --- > include/kunit/test.h | 5 ++++ > include/linux/kasan.h | 6 +++++ > lib/kunit/test.c | 13 ++++++---- > lib/test_kasan.c | 56 +++++++++++++++++++++++++++++++++++++++---- > mm/kasan/report.c | 30 +++++++++++++++++++++++ > 5 files changed, 101 insertions(+), 9 deletions(-) > > diff --git a/include/kunit/test.h b/include/kunit/test.h > index ac59d18e6bab..1dc3d118f64b 100644 > --- a/include/kunit/test.h > +++ b/include/kunit/test.h > @@ -225,6 +225,11 @@ struct kunit { > struct list_head resources; /* Protected by lock. */ > }; > > +static inline void kunit_set_failure(struct kunit *test) > +{ > + WRITE_ONCE(test->success, false); > +} > + > void kunit_init_test(struct kunit *test, const char *name, char *log); > > int kunit_run_tests(struct kunit_suite *suite); > diff --git a/include/linux/kasan.h b/include/linux/kasan.h > index 5cde9e7c2664..148eaef3e003 100644 > --- a/include/linux/kasan.h > +++ b/include/linux/kasan.h > @@ -14,6 +14,12 @@ struct task_struct; > #include <asm/kasan.h> > #include <asm/pgtable.h> > > +/* kasan_data struct is used in KUnit tests for KASAN expected failures */ > +struct kunit_kasan_expectation { > + bool report_expected; > + bool report_found; > +}; > + > extern unsigned char kasan_early_shadow_page[PAGE_SIZE]; > extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE]; > extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD]; > diff --git a/lib/kunit/test.c b/lib/kunit/test.c > index 2cb7c6220a00..030a3281591e 100644 > --- a/lib/kunit/test.c > +++ b/lib/kunit/test.c > @@ -10,16 +10,12 @@ > #include <linux/kernel.h> > #include <linux/kref.h> > #include <linux/sched/debug.h> > +#include <linux/sched.h> > > #include "debugfs.h" > #include "string-stream.h" > #include "try-catch-impl.h" > > -static void kunit_set_failure(struct kunit *test) > -{ > - WRITE_ONCE(test->success, false); > -} > - > static void kunit_print_tap_version(void) > { > static bool kunit_has_printed_tap_version; > @@ -288,6 +284,10 @@ static void kunit_try_run_case(void *data) > struct kunit_suite *suite = ctx->suite; > struct kunit_case *test_case = ctx->test_case; > > +#if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT)) > + current->kunit_test = test; > +#endif /* IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT) */ > + > /* > * kunit_run_case_internal may encounter a fatal error; if it does, > * abort will be called, this thread will exit, and finally the parent > @@ -603,6 +603,9 @@ void kunit_cleanup(struct kunit *test) > spin_unlock(&test->lock); > kunit_remove_resource(test, res); > } > +#if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT)) > + current->kunit_test = NULL; > +#endif /* IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT)*/ > } > EXPORT_SYMBOL_GPL(kunit_cleanup); > > diff --git a/lib/test_kasan.c b/lib/test_kasan.c > index 3872d250ed2c..dbfa0875ee09 100644 > --- a/lib/test_kasan.c > +++ b/lib/test_kasan.c > @@ -23,12 +23,60 @@ > > #include <asm/page.h> > > -/* > - * Note: test functions are marked noinline so that their names appear in > - * reports. > +#include <kunit/test.h> > + > +static struct kunit_resource resource; > +static struct kunit_kasan_expectation fail_data; > +static bool multishot; > +static int orig_panic_on_warn; > + > +static int kasan_test_init(struct kunit *test) > +{ > + /* > + * Temporarily enable multi-shot mode and set panic_on_warn=0. > + * Otherwise, we'd only get a report for the first case. > + */ > + multishot = kasan_save_enable_multi_shot(); > + > + orig_panic_on_warn = panic_on_warn; > + panic_on_warn = 0; > + > + return 0; > +} > + > +static void kasan_test_exit(struct kunit *test) > +{ > + kasan_restore_multi_shot(multishot); > + > + /* Restore panic_on_warn */ Nit: no need for this comment, I think it's clear that here we're restoring stuff we saved in kasan_test_init(). > + panic_on_warn = orig_panic_on_warn; > +} > + > +/** > + * KUNIT_EXPECT_KASAN_FAIL() - Causes a test failure when the expression does > + * not cause a KASAN error. This uses a KUnit resource named "kasan_data." Do > + * Do not use this name for a KUnit resource outside here. > + * > */ > +#define KUNIT_EXPECT_KASAN_FAIL(test, condition) do { \ > + struct kunit_resource *res; \ > + struct kunit_kasan_expectation *kasan_data; \ > + fail_data.report_expected = true; \ > + fail_data.report_found = false; \ > + kunit_add_named_resource(test, \ > + NULL, \ > + NULL, \ > + &resource, \ > + "kasan_data", &fail_data); \ > + condition; \ > + res = kunit_find_named_resource(test, "kasan_data"); \ Is res going to be == &resource here? If so, no need to call kunit_find_named_resource(). > + kasan_data = res->data; \ > + KUNIT_EXPECT_EQ(test, \ > + kasan_data->report_expected, \ > + kasan_data->report_found); \ Nit: no need to add kasan_data var, just use resource.data->report_expected. > + kunit_put_resource(res); \ > +} while (0) > > -static noinline void __init kmalloc_oob_right(void) > { > char *ptr; > size_t size = 123; > diff --git a/mm/kasan/report.c b/mm/kasan/report.c > index 5ef9f24f566b..497477c4b679 100644 > --- a/mm/kasan/report.c > +++ b/mm/kasan/report.c > @@ -32,6 +32,8 @@ > > #include <asm/sections.h> > > +#include <kunit/test.h> > + > #include "kasan.h" > #include "../slab.h" > > @@ -455,12 +457,35 @@ static bool report_enabled(void) > return !test_and_set_bit(KASAN_BIT_REPORTED, &kasan_flags); > } > > +#if IS_ENABLED(CONFIG_KUNIT) > +void kasan_update_kunit_status(struct kunit *cur_test) This isn't used outside of report.c, right? Then _static_ void kasan_update_kunit_status(). > +{ > + struct kunit_resource *resource; > + struct kunit_kasan_expectation *kasan_data; > + > + if (!kunit_find_named_resource(cur_test, "kasan_data")) { > + kunit_set_failure(cur_test); > + return; > + } > + > + resource = kunit_find_named_resource(cur_test, "kasan_data"); Do this before the if above, and then check if (!resource), will save you a call to kunit_find_named_resource(). > + kasan_data = resource->data; > + kasan_data->report_found = true; No need for kasan_data var (if it can't be NULL or something), just do: resource->data->report_found = true; > +} > +#endif /* IS_ENABLED(CONFIG_KUNIT) */ > + > void kasan_report_invalid_free(void *object, unsigned long ip) > { > unsigned long flags; > u8 tag = get_tag(object); > > object = reset_tag(object); > + > +#if IS_ENABLED(CONFIG_KUNIT) > + if (current->kunit_test) > + kasan_update_kunit_status(current->kunit_test); > +#endif /* IS_ENABLED(CONFIG_KUNIT) */ > + > start_report(&flags); > pr_err("BUG: KASAN: double-free or invalid-free in %pS\n", (void *)ip); > print_tags(tag, object); > @@ -481,6 +506,11 @@ void __kasan_report(unsigned long addr, size_t size, bool is_write, unsigned lon > if (likely(!report_enabled())) > return; > > +#if IS_ENABLED(CONFIG_KUNIT) > + if (current->kunit_test) > + kasan_update_kunit_status(current->kunit_test); > +#endif /* IS_ENABLED(CONFIG_KUNIT) */ > + > disable_trace_on_warning(); > > tagged_addr = (void *)addr; > -- > 2.26.0.292.g33ef6b2f38-goog > > -- > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/20200402204639.161637-2-trishalfonso%40google.com.
