KUnit: KASAN Integration

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@oracle.com/T/#t)

Signed-off-by: Patricia Alfonso <trishalfonso@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20200915035828.570483-3-davidgow@google.com
Link: https://lkml.kernel.org/r/20200910070331.3358048-3-davidgow@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Patricia Alfonso 2020-10-13 16:55:02 -07:00 committed by Linus Torvalds
parent 393824f650
commit 83c4e7a036
5 changed files with 96 additions and 7 deletions

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@ -224,6 +224,11 @@ 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);

View File

@ -14,6 +14,12 @@ struct task_struct;
#include <linux/pgtable.h>
#include <asm/kasan.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];

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@ -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
@ -602,6 +602,9 @@ 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);

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@ -23,6 +23,8 @@
#include <asm/page.h>
#include <kunit/test.h>
#include "../mm/kasan/kasan.h"
#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_SHADOW_SCALE_SIZE)
@ -32,14 +34,55 @@
* are not eliminated as dead code.
*/
int kasan_int_result;
void *kasan_ptr_result;
int kasan_int_result;
static struct kunit_resource resource;
static struct kunit_kasan_expectation fail_data;
static bool multishot;
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();
return 0;
}
static void kasan_test_exit(struct kunit *test)
{
kasan_restore_multi_shot(multishot);
}
/**
* 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 { \
fail_data.report_expected = true; \
fail_data.report_found = false; \
kunit_add_named_resource(test, \
NULL, \
NULL, \
&resource, \
"kasan_data", &fail_data); \
condition; \
KUNIT_EXPECT_EQ(test, \
fail_data.report_expected, \
fail_data.report_found); \
} while (0)
/*
* Note: test functions are marked noinline so that their names appear in
* reports.
*/
static noinline void __init kmalloc_oob_right(void)
{
char *ptr;

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@ -33,6 +33,8 @@
#include <asm/sections.h>
#include <kunit/test.h>
#include "kasan.h"
#include "../slab.h"
@ -464,12 +466,37 @@ static bool report_enabled(void)
return !test_and_set_bit(KASAN_BIT_REPORTED, &kasan_flags);
}
#if IS_ENABLED(CONFIG_KUNIT)
static void kasan_update_kunit_status(struct kunit *cur_test)
{
struct kunit_resource *resource;
struct kunit_kasan_expectation *kasan_data;
resource = kunit_find_named_resource(cur_test, "kasan_data");
if (!resource) {
kunit_set_failure(cur_test);
return;
}
kasan_data = (struct kunit_kasan_expectation *)resource->data;
kasan_data->report_found = true;
kunit_put_resource(resource);
}
#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);
@ -488,6 +515,11 @@ static void __kasan_report(unsigned long addr, size_t size, bool is_write,
void *untagged_addr;
unsigned long flags;
#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;