diff options
| author | Alexander Potapenko <glider@google.com> | 2023-03-06 12:13:22 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-03-28 16:20:14 -0700 |
| commit | 6204c9ab4a5a05a72e04c12276fffdd6c6636489 (patch) | |
| tree | ebc38eb9dace54e83e0a0649f2ba6fdc92abb8ac /mm/kmsan | |
| parent | 8e00b2dffd822b34d8d1c627dc19f0743f9f5ac6 (diff) | |
kmsan: add test_stackdepot_roundtrip
Ensure that KMSAN does not report false positives in instrumented callers
of stack_depot_save(), stack_depot_print(), and stack_depot_fetch().
Link: https://lkml.kernel.org/r/20230306111322.205724-2-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/kmsan')
| -rw-r--r-- | mm/kmsan/kmsan_test.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/mm/kmsan/kmsan_test.c b/mm/kmsan/kmsan_test.c index 7095d3fbb23a..d9eb141c27aa 100644 --- a/mm/kmsan/kmsan_test.c +++ b/mm/kmsan/kmsan_test.c @@ -551,6 +551,36 @@ static void test_long_origin_chain(struct kunit *test) KUNIT_EXPECT_TRUE(test, report_matches(&expect)); } +/* + * Test case: ensure that saving/restoring/printing stacks to/from stackdepot + * does not trigger errors. + * + * KMSAN uses stackdepot to store origin stack traces, that's why we do not + * instrument lib/stackdepot.c. Yet it must properly mark its outputs as + * initialized because other kernel features (e.g. netdev tracker) may also + * access stackdepot from instrumented code. + */ +static void test_stackdepot_roundtrip(struct kunit *test) +{ + unsigned long src_entries[16], *dst_entries; + unsigned int src_nentries, dst_nentries; + EXPECTATION_NO_REPORT(expect); + depot_stack_handle_t handle; + + kunit_info(test, "testing stackdepot roundtrip (no reports)\n"); + + src_nentries = + stack_trace_save(src_entries, ARRAY_SIZE(src_entries), 1); + handle = stack_depot_save(src_entries, src_nentries, GFP_KERNEL); + stack_depot_print(handle); + dst_nentries = stack_depot_fetch(handle, &dst_entries); + KUNIT_EXPECT_TRUE(test, src_nentries == dst_nentries); + + kmsan_check_memory((void *)dst_entries, + sizeof(*dst_entries) * dst_nentries); + KUNIT_EXPECT_TRUE(test, report_matches(&expect)); +} + static struct kunit_case kmsan_test_cases[] = { KUNIT_CASE(test_uninit_kmalloc), KUNIT_CASE(test_init_kmalloc), @@ -573,6 +603,7 @@ static struct kunit_case kmsan_test_cases[] = { KUNIT_CASE(test_memset32), KUNIT_CASE(test_memset64), KUNIT_CASE(test_long_origin_chain), + KUNIT_CASE(test_stackdepot_roundtrip), {}, }; |