KASAN-KUnit Integration
Subsystems (8)
v10 cover KASAN-KUnit Integration
This patchset contains everything needed to integrate KASAN and KUnit.
KUnit will be able to:
(1) Fail tests when an unexpected KASAN error occurs
(2) Pass tests when an expected KASAN error occurs
Convert KASAN tests to KUnit with the exception of copy_user_test because KUnit is unable to test those.
Add documentation on how to run the KASAN tests with KUnit and what to expect when running these tests.
This patchset depends on:
- "kunit: extend kunit resources API" [1]
- This is already present in the kselftest/kunit branch
I'd _really_ like to get this into 5.9 if possible: we also have some other changes which depend on some things here.
Changes from v9:
- Rebased on top of linux-next (20200731) + kselftest/kunit and [7]
- Note that the kasan_rcu_uaf test has not been ported to KUnit, and remains in test_kasan_module. This is because:
(a) KUnit's expect failure will not check if the RCU stacktraces show.
(b) KUnit is unable to link the failure to the test, as it occurs in an RCU callback.
Changes from v8:
- Rebased on top of kselftest/kunit
- (Which, with this patchset, should rebase cleanly on 5.8-rc7)
- Renamed the KUnit test suite, config name to patch the proposed naming guidelines for KUnit tests[6]
Changes from v7:
- Rebased on top of kselftest/kunit
- Rebased on top of v4 of the kunit resources API[1]
- Rebased on top of v4 of the FORTIFY_SOURCE fix[2,3,4]
- Updated the Kconfig entry to support KUNIT_ALL_TESTS
Changes from v6:
- Rebased on top of kselftest/kunit
- Rebased on top of Daniel Axtens' fix for FORTIFY_SOURCE incompatibilites [2]
- Removed a redundant report_enabled() check.
- Fixed some places with out of date Kconfig names in the documentation.
Changes from v5:
- Split out the panic_on_warn changes to a separate patch.
- Fix documentation to fewer to the new Kconfig names.
- Fix some changes which were in the wrong patch.
- Rebase on top of kselftest/kunit (currently identical to 5.7-rc1)
Changes from v4:
- KASAN no longer will panic on errors if both panic_on_warn and kasan_multishot are enabled.
- As a result, the KASAN tests will no-longer disable panic_on_warn.
- This also means panic_on_warn no-longer needs to be exported.
- The use of temporary "kasan_data" variables has been cleaned up somewhat.
- A potential refcount/resource leak should multiple KASAN errors appear during an assertion was fixed.
- Some wording changes to the KASAN test Kconfig entries.
Changes from v3:
- KUNIT_SET_KASAN_DATA and KUNIT_DO_EXPECT_KASAN_FAIL have been combined and included in KUNIT_DO_EXPECT_KASAN_FAIL() instead.
- Reordered logic in kasan_update_kunit_status() in report.c to be easier to read.
- Added comment to not use the name "kasan_data" for any kunit tests outside of KUNIT_EXPECT_KASAN_FAIL().
Changes since v2:
- Due to Alan's changes in [1], KUnit can be built as a module.
- The name of the tests that could not be run with KUnit has been changed to be more generic: test_kasan_module.
- Documentation on how to run the new KASAN tests and what to expect when running them has been added.
- Some variables and functions are now static.
- Now save/restore panic_on_warn in a similar way to kasan_multi_shot and renamed the init/exit functions to be more generic to accommodate.
- Due to [4] in kasan_strings, kasan_memchr, and kasan_memcmp will fail if CONFIG_AMD_MEM_ENCRYPT is enabled so return early and print message explaining this circumstance.
- Changed preprocessor checks to C checks where applicable.
Changes since v1:
- Make use of Alan Maguire's suggestion to use his patch that allows static resources for integration instead of adding a new attribute to the kunit struct
- All KUNIT_EXPECT_KASAN_FAIL statements are local to each test
- The definition of KUNIT_EXPECT_KASAN_FAIL is local to the test_kasan.c file since it seems this is the only place this will be used.
- Integration relies on KUnit being builtin
- copy_user_test has been separated into its own file since KUnit is unable to test these. This can be run as a module just as before, using CONFIG_TEST_KASAN_USER
- The addition to the current task has been separated into its own patch as this is a significant enough change to be on its own.
[1] https://lore.kernel.org/linux-kselftest/CAFd5g46Uu_5TG89uOm0Dj5CMq+11cwjBnsd-k_CVy6bQUeU4Jw@mail.gmail.com/T/#t
[2] https://lore.kernel.org/linux-mm/[email protected]/
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=adb72ae1915db28f934e9e02c18bfcea2f3ed3b7
[4] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=47227d27e2fcb01a9e8f5958d8997cf47a820afc
[5] https://bugzilla.kernel.org/show_bug.cgi?id=206337
[6] https://lore.kernel.org/linux-kselftest/[email protected]/
[7] https://lkml.org/lkml/2020/7/31/571
David Gow (1):
mm: kasan: Do not panic if both panic_on_warn and kasan_multishot set
Patricia Alfonso (4):
Add KUnit Struct to Current Task
KUnit: KASAN Integration
KASAN: Port KASAN Tests to KUnit KASAN: Testing Documentation
Documentation/dev-tools/kasan.rst | 70 +++ include/kunit/test.h | 5 + include/linux/kasan.h | 6 + include/linux/sched.h | 4 + lib/Kconfig.kasan | 22 +- lib/Makefile | 7 +- lib/kasan_kunit.c | 770 +++++++++++++++++++++++++ lib/kunit/test.c | 13 +- lib/test_kasan.c | 903 ------------------------------ lib/test_kasan_module.c | 111 ++++ mm/kasan/report.c | 34 +- 11 files changed, 1028 insertions(+), 917 deletions(-) create mode 100644 lib/kasan_kunit.c delete mode 100644 lib/test_kasan.c create mode 100644 lib/test_kasan_module.c
Signature · 1 line
2.28.0.163.g6104cc2f0b6-goog
PATCH v10 1/5 Add KUnit Struct to Current Task
From: Patricia Alfonso <[email protected]>
In order to integrate debugging tools like KASAN into the KUnit framework, add KUnit struct to the current task to keep track of the current KUnit test.
--- include/linux/sched.h | 4 ++++ 1 file changed, 4 insertions(+)
include/linux/sched.h +4 -0
@@ -1196,6 +1196,10 @@ struct task_struct {struct kcsan_ctx kcsan_ctx;#endif +#if IS_ENABLED (CONFIG_KUNIT ) +struct kunit *kunit_test; +#endif +#ifdef CONFIG_FUNCTION_GRAPH_TRACER /* Index of current stored address in ret_stack: */ int curr_ret_stack;
Signature · 1 line
2.28.0.163.g6104cc2f0b6-goog
PATCH v10 2/5 KUnit: KASAN Integration
In reply to David GowFrom: Patricia Alfonso <[email protected]>
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/[email protected]/T/#t)
--- include/kunit/test.h | 5 +++++ include/linux/kasan.h | 6 ++++++ lib/kunit/test.c | 13 +++++++----- lib/test_kasan.c | 47 +++++++++++++++++++++++++++++++++++++++++-- mm/kasan/report.c | 32 +++++++++++++++++++++++++++++ 5 files changed, 96 insertions(+), 7 deletions(-)
include/kunit/test.h +5 -0
@@ -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);
include/linux/kasan.h +6 -0
@@ -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 ];
lib/kunit/test.c +8 -5
@@ -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);
lib/test_kasan.c +45 -2
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mm/kasan/report.c +32 -0
@@ -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;
Signature · 1 line
2.28.0.163.g6104cc2f0b6-goog
PATCH v10 3/5 KASAN: Port KASAN Tests to KUnit
In reply to David GowFrom: Patricia Alfonso <[email protected]>
Transfer all previous tests for KASAN to KUnit so they can be run more easily. Using kunit_tool, developers can run these tests with their other KUnit tests and see "pass" or "fail" with the appropriate KASAN report instead of needing to parse each KASAN report to test KASAN functionalities. All KASAN reports are still printed to dmesg.
Stack tests do not work properly when KASAN_STACK is enabled so those tests use a check for "if IS_ENABLED(CONFIG_KASAN_STACK)" so they only run if stack instrumentation is enabled. If KASAN_STACK is not enabled, KUnit will print a statement to let the user know this test was not run with KASAN_STACK enabled.
copy_user_test and kasan_rcu_uaf cannot be run in KUnit so there is a separate test file for those tests, which can be run as before as a module.
--- lib/Kconfig.kasan | 22 +- lib/Makefile | 7 +- lib/kasan_kunit.c | 770 ++++++++++++++++++++++++++++++++ lib/test_kasan.c | 946 ---------------------------------------- lib/test_kasan_module.c | 111 +++++ 5 files changed, 902 insertions(+), 954 deletions(-) create mode 100644 lib/kasan_kunit.c delete mode 100644 lib/test_kasan.c create mode 100644 lib/test_kasan_module.c
lib/Kconfig.kasan +17 -5
@@ -167,12 +167,24 @@ config KASAN_VMALLOC for KASAN to detect more sorts of errors (and to support vmapped stacks), but at the cost of higher memory usage. -config TEST_KASAN - tristate "Module for testing KASAN for bug detection" - depends on m +config KASAN_KUNIT_TEST + tristate "KUnit-compatible tests of KASAN bug detection capabilities" if !KUNIT_ALL_TESTS + depends on KASAN && KUNIT + default KUNIT_ALL_TESTS help - This is a test module doing various nasty things like - out of bounds accesses, use after free. It is useful for testing + This is a KUnit test suite doing various nasty things like + out of bounds and use after free accesses. It is useful for testing kernel debugging features like KASAN. + For more information on KUnit and unit tests in general, please refer + to the KUnit documentation in Documentation/dev-tools/kunit + +config TEST_KASAN_MODULE + tristate "KUnit-incompatible tests of KASAN bug detection capabilities" + depends on m && KASAN + help + This is a part of the KASAN test suite that is incompatible with + KUnit. Currently includes tests that do bad copy_from/to_user + accesses. + endif # KASAN
lib/Makefile +4 -3
@@ -60,9 +60,10 @@ CFLAGS_test_bitops.o += -Werror obj-$(CONFIG_TEST_SYSCTL) += test_sysctl.o obj-$(CONFIG_TEST_HASH) += test_hash.o test_siphash.o obj-$(CONFIG_TEST_IDA) += test_ida.o -obj-$(CONFIG_TEST_KASAN) += test_kasan.o -CFLAGS_test_kasan.o += -fno-builtin -CFLAGS_test_kasan.o += $(call cc-disable-warning, vla) +obj-$(CONFIG_KASAN_KUNIT_TEST) += kasan_kunit.o +CFLAGS_kasan_kunit.o += -fno-builtin +CFLAGS_kasan_kunit.o += $(call cc-disable-warning, vla) +obj-$(CONFIG_TEST_KASAN_MODULE) += test_kasan_module.o obj-$(CONFIG_TEST_UBSAN) += test_ubsan.o CFLAGS_test_ubsan.o += $(call cc-disable-warning, vla) UBSAN_SANITIZE_test_ubsan.o := y
lib/kasan_kunit.c new file +770 -0
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lib/test_kasan.c deleted +0 -946
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lib/test_kasan_module.c new file +111 -0
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Signature · 1 line
2.28.0.163.g6104cc2f0b6-goog
Re: [PATCH v10 3/5] KASAN: Port KASAN Tests to KUnit
Quoted 24 lines · David Gow
From: Patricia Alfonso <[email protected]>
Transfer all previous tests for KASAN to KUnit so they can be run more easily. Using
kunit_tool, developers can run these tests with their other KUnit tests and see "pass" or "fail" with the appropriate KASAN report instead of needing to parse each KASAN report to test KASAN functionalities. All KASAN reports are still printed to dmesg.Stack tests do not work properly when
KASAN_STACKis enabled so those tests use a check for "ifIS_ENABLED(CONFIG_KASAN_STACK)" so they only run if stack instrumentation is enabled. IfKASAN_STACKis not enabled, KUnit will print a statement to let the user know this test was not run withKASAN_STACKenabled.
copy_user_testandkasan_rcu_uafcannot be run in KUnit so there is a separate test file for those tests, which can be run as before as a module.Signed-off-by Patricia Alfonso <[email protected]>Signed-off-by David Gow <[email protected]>Reviewed-by Brendan Higgins <[email protected]>Reviewed-by Andrey Konovalov <[email protected]>Reviewed-by Dmitry Vyukov <[email protected]>
Quoted 10 lines
--- lib/Kconfig.kasan | 22 +- lib/Makefile | 7 +- lib/kasan_kunit.c | 770 ++++++++++++++++++++++++++++++++ lib/test_kasan.c | 946 ---------------------------------------- lib/test_kasan_module.c | 111 +++++ 5 files changed, 902 insertions(+), 954 deletions(-) create mode 100644 lib/kasan_kunit.c delete mode 100644 lib/test_kasan.c create mode 100644 lib/test_kasan_module.c
Whoops -- this patch had a few nasty whitespace issues make it through. I'll send out a new version with those fixed.
I'm pondering splitting it up to do the file rename (test_kasan.c->kasan_kunit.c) separately as well, as git's rename detection is not particularly happy with it.
Sorry,
-- David
Re: [PATCH v10 3/5] KASAN: Port KASAN Tests to KUnit
Quoted 37 lines · David Gow
Quoted 24 lines · David Gow
From: Patricia Alfonso <[email protected]>
Transfer all previous tests for KASAN to KUnit so they can be run more easily. Using
kunit_tool, developers can run these tests with their other KUnit tests and see "pass" or "fail" with the appropriate KASAN report instead of needing to parse each KASAN report to test KASAN functionalities. All KASAN reports are still printed to dmesg.Stack tests do not work properly when
KASAN_STACKis enabled so those tests use a check for "ifIS_ENABLED(CONFIG_KASAN_STACK)" so they only run if stack instrumentation is enabled. IfKASAN_STACKis not enabled, KUnit will print a statement to let the user know this test was not run withKASAN_STACKenabled.
copy_user_testandkasan_rcu_uafcannot be run in KUnit so there is a separate test file for those tests, which can be run as before as a module.Signed-off-by Patricia Alfonso <[email protected]>Signed-off-by David Gow <[email protected]>Reviewed-by Brendan Higgins <[email protected]>Reviewed-by Andrey Konovalov <[email protected]>Reviewed-by Dmitry Vyukov <[email protected]>Quoted 10 lines
--- lib/Kconfig.kasan | 22 +- lib/Makefile | 7 +- lib/kasan_kunit.c | 770 ++++++++++++++++++++++++++++++++ lib/test_kasan.c | 946 ---------------------------------------- lib/test_kasan_module.c | 111 +++++ 5 files changed, 902 insertions(+), 954 deletions(-) create mode 100644 lib/kasan_kunit.c delete mode 100644 lib/test_kasan.c create mode 100644 lib/test_kasan_module.c
Quoted 6 lines
Whoops -- this patch had a few nasty whitespace issues make it through. I'll send out a new version with those fixed.
I'm pondering splitting it up to do the file rename (
test_kasan.c->kasan_kunit.c) separately as well, as git's rename detection is not particularly happy with it.
Maybe also name it kunit_kasan.c? Probably in the future we'll have kunit_kmsan.c, etc.
Re: [PATCH v10 3/5] KASAN: Port KASAN Tests to KUnit
Quoted 42 lines · Andrey Konovalov
Quoted 40 lines · David Gow
Quoted 24 lines · David Gow
From: Patricia Alfonso <[email protected]>
Transfer all previous tests for KASAN to KUnit so they can be run more easily. Using
kunit_tool, developers can run these tests with their other KUnit tests and see "pass" or "fail" with the appropriate KASAN report instead of needing to parse each KASAN report to test KASAN functionalities. All KASAN reports are still printed to dmesg.Stack tests do not work properly when
KASAN_STACKis enabled so those tests use a check for "ifIS_ENABLED(CONFIG_KASAN_STACK)" so they only run if stack instrumentation is enabled. IfKASAN_STACKis not enabled, KUnit will print a statement to let the user know this test was not run withKASAN_STACKenabled.
copy_user_testandkasan_rcu_uafcannot be run in KUnit so there is a separate test file for those tests, which can be run as before as a module.Signed-off-by Patricia Alfonso <[email protected]>Signed-off-by David Gow <[email protected]>Reviewed-by Brendan Higgins <[email protected]>Reviewed-by Andrey Konovalov <[email protected]>Reviewed-by Dmitry Vyukov <[email protected]>Quoted 10 lines
--- lib/Kconfig.kasan | 22 +- lib/Makefile | 7 +- lib/kasan_kunit.c | 770 ++++++++++++++++++++++++++++++++ lib/test_kasan.c | 946 ---------------------------------------- lib/test_kasan_module.c | 111 +++++ 5 files changed, 902 insertions(+), 954 deletions(-) create mode 100644 lib/kasan_kunit.c delete mode 100644 lib/test_kasan.c create mode 100644 lib/test_kasan_module.cWhoops -- this patch had a few nasty whitespace issues make it through. I'll send out a new version with those fixed.
Quoted 6 lines
Quoted 3 lines
I'm pondering splitting it up to do the file rename (
test_kasan.c->kasan_kunit.c) separately as well, as git's rename detection is not particularly happy with it.Maybe also name it
kunit_kasan.c? Probably in the future we'll havekunit_kmsan.c, etc.
The name here uses _kunit as a suffix as part of a plan to standardise that for all KUnit tests.
There's some draft documentation for the proposed naming guidelines here:
https://lore.kernel.org/linux-kselftest/[email protected]/
(The idea here was for kunit tests for modules to nicely sort next to the corresponding modules, which is why _kunit is a suffix, but that doesn't really apply for something built-in like KASAN.)
-- David
PATCH v10 4/5 KASAN: Testing Documentation
In reply to David GowFrom: Patricia Alfonso <[email protected]>
Include documentation on how to test KASAN using CONFIG_TEST_KASAN_KUNIT and CONFIG_TEST_KASAN_MODULE.
--- Documentation/dev-tools/kasan.rst | 70 +++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+)
Documentation/dev-tools/kasan.rst +70 -0
@@ -281,3 +281,73 @@ unmapped. This will require changes in arch-specific code. This allows ``VMAP_STACK`` support on x86, and can simplify support of architectures that do not have a fixed module region. + +CONFIG_KASAN_KUNIT_TEST & CONFIG_TEST_KASAN_MODULE +-------------------------------------------------- + +``CONFIG_KASAN_KUNIT_TEST`` utilizes the KUnit Test Framework for testing. +This means each test focuses on a small unit of functionality and +there are a few ways these tests can be run. + +Each test will print the KASAN report if an error is detected and then +print the number of the test and the status of the test: + +pass:: + + ok 28 - kmalloc_double_kzfree +or, if kmalloc failed:: + + # kmalloc_large_oob_right: ASSERTION FAILED at lib/test_kasan.c:163 + Expected ptr is not null, but is + not ok 4 - kmalloc_large_oob_right +or, if a KASAN report was expected, but not found:: + + # kmalloc_double_kzfree: EXPECTATION FAILED at lib/test_kasan.c:629 + Expected kasan_data->report_expected == kasan_data->report_found, but + kasan_data->report_expected == 1 + kasan_data->report_found == 0 + not ok 28 - kmalloc_double_kzfree + +All test statuses are tracked as they run and an overall status will +be printed at the end:: + + ok 1 - kasan_kunit_test + +or:: + + not ok 1 - kasan_kunit_test + +(1) Loadable Module +~~~~~~~~~~~~~~~~~~~~ + +With ``CONFIG_KUNIT`` enabled, ``CONFIG_KASAN_KUNIT_TEST`` can be built as +a loadable module and run on any architecture that supports KASAN +using something like insmod or modprobe. + +(2) Built-In +~~~~~~~~~~~~~ + +With ``CONFIG_KUNIT`` built-in, ``CONFIG_KASAN_KUNIT_TEST`` can be built-in +on any architecure that supports KASAN. These and any other KUnit +tests enabled will run and print the results at boot as a late-init +call. + +(3) Using kunit_tool +~~~~~~~~~~~~~~~~~~~~~ + +With ``CONFIG_KUNIT`` and ``CONFIG_KASAN_KUNIT_TEST`` built-in, we can also +use kunit_tool to see the results of these along with other KUnit +tests in a more readable way. This will not print the KASAN reports +of tests that passed. Use `KUnit documentation <https://www.kernel.org/doc/html/latest/dev-tools/kunit/index.html>`_ for more up-to-date +information on kunit_tool. + +.. _KUnit: https://www.kernel.org/doc/html/latest/dev-tools/kunit/index.html + +``CONFIG_TEST_KASAN_MODULE`` is a set of KASAN tests that could not be +converted to KUnit. These tests can be run only as a module with +``CONFIG_TEST_KASAN_MODULE`` built as a loadable module and +``CONFIG_KASAN`` built-in. The type of error expected and the +function being run is printed before the expression expected to give +an error. Then the error is printed, if found, and that test +should be interpretted to pass only if the error was the one expected +by the test.
Signature · 1 line
2.28.0.163.g6104cc2f0b6-goog
PATCH v10 5/5 mm: kasan: Do not panic if both panic_on_warn and kasan_multishot set
In reply to David GowKASAN errors will currently trigger a panic when panic_on_warn is set. This renders kasan_multishot useless, as further KASAN errors won't be reported if the kernel has already paniced. By making kasan_multishot disable this behaviour for KASAN errors, we can still have the benefits of panic_on_warn for non-KASAN warnings, yet be able to use kasan_multishot.
This is particularly important when running KASAN tests, which need to trigger multiple KASAN errors: previously these would panic the system if panic_on_warn was set, now they can run (and will panic the system should non-KASAN warnings show up).
--- mm/kasan/report.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
mm/kasan/report.c +1 -1
@@ -95,7 +95,7 @@ static void end_report(unsigned long *flags)pr_err ("==================================================================\n" );add_taint (TAINT_BAD_PAGE ,LOCKDEP_NOW_UNRELIABLE );spin_unlock_irqrestore (&report_lock, *flags); -if (panic_on_warn) { +if (panic_on_warn && !test_bit (KASAN_BIT_MULTI_SHOT , &kasan_flags)) {/* * This thread may hit another WARN() in the panic path. * Resetting this prevents additional WARN() from panicking the
Signature · 1 line
2.28.0.163.g6104cc2f0b6-goog
Quoted 13 lines · David Gow
This patchset contains everything needed to integrate KASAN and KUnit.
KUnit will be able to:
(1) Fail tests when an unexpected KASAN error occurs
(2) Pass tests when an expected KASAN error occursConvert KASAN tests to KUnit with the exception of
copy_user_testbecause KUnit is unable to test those.Add documentation on how to run the KASAN tests with KUnit and what to expect when running these tests.
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This patchset depends on:
- "kunit: extend kunit resources API" [1]
- This is already present in the kselftest/kunit branchI'd _really_ like to get this into 5.9 if possible: we also have some other changes which depend on some things here.
+Andew, could you PTAL at this patchset?
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Changes from v9:
- Rebased on top of linux-next (20200731) + kselftest/kunit and [7]
- Note that thekasan_rcu_uaftest has not been ported to KUnit, and remains intest_kasan_module. This is because:
(a) KUnit's expect failure will not check if the RCU stacktraces show.
(b) KUnit is unable to link the failure to the test, as it occurs in an RCU callback.Changes from v8:
- Rebased on top of kselftest/kunit
- (Which, with this patchset, should rebase cleanly on 5.8-rc7)
- Renamed the KUnit test suite, config name to patch the proposed naming guidelines for KUnit tests[6]Changes from v7:
- Rebased on top of kselftest/kunit
- Rebased on top of v4 of the kunit resources API[1]
- Rebased on top of v4 of theFORTIFY_SOURCEfix[2,3,4]
- Updated theKconfigentry to supportKUNIT_ALL_TESTSChanges from v6:
- Rebased on top of kselftest/kunit
- Rebased on top of Daniel Axtens' fix forFORTIFY_SOURCEincompatibilites [2]
- Removed a redundantreport_enabled()check.
- Fixed some places with out of dateKconfignames in the documentation.Changes from v5:
- Split out thepanic_on_warnchanges to a separate patch.
- Fix documentation to fewer to the newKconfignames.
- Fix some changes which were in the wrong patch.
- Rebase on top of kselftest/kunit (currently identical to 5.7-rc1)Changes from v4:
- KASAN no longer will panic on errors if bothpanic_on_warnandkasan_multishotare enabled.
- As a result, the KASAN tests will no-longer disablepanic_on_warn.
- This also meanspanic_on_warnno-longer needs to be exported.
- The use of temporary "kasan_data" variables has been cleaned up somewhat.
- A potential refcount/resource leak should multiple KASAN errors appear during an assertion was fixed.
- Some wording changes to the KASAN testKconfigentries.Changes from v3:
-KUNIT_SET_KASAN_DATAandKUNIT_DO_EXPECT_KASAN_FAILhave been combined and included inKUNIT_DO_EXPECT_KASAN_FAIL()instead.
- Reordered logic inkasan_update_kunit_status()inreport.cto be easier to read.
- Added comment to not use the name "kasan_data" for any kunit tests outside ofKUNIT_EXPECT_KASAN_FAIL().Changes since v2:
- Due to Alan's changes in [1], KUnit can be built as a module.
- The name of the tests that could not be run with KUnit has been changed to be more generic:test_kasan_module.
- Documentation on how to run the new KASAN tests and what to expect when running them has been added.
- Some variables and functions are now static.
- Now save/restorepanic_on_warnin a similar way tokasan_multi_shotand renamed the init/exit functions to be more generic to accommodate.
- Due to [4] inkasan_strings,kasan_memchr, andkasan_memcmpwill fail ifCONFIG_AMD_MEM_ENCRYPTis enabled so return early and print message explaining this circumstance.
- Changed preprocessor checks to C checks where applicable.Changes since v1:
- Make use of Alan Maguire's suggestion to use his patch that allows static resources for integration instead of adding a new attribute to the kunit struct
- AllKUNIT_EXPECT_KASAN_FAILstatements are local to each test
- The definition ofKUNIT_EXPECT_KASAN_FAILis local to thetest_kasan.cfile since it seems this is the only place this will be used.
- Integration relies on KUnit being builtin
-copy_user_testhas been separated into its own file since KUnit is unable to test these. This can be run as a module just as before, usingCONFIG_TEST_KASAN_USER
- The addition to the current task has been separated into its own patch as this is a significant enough change to be on its own.[1] https://lore.kernel.org/linux-kselftest/CAFd5g46Uu_5TG89uOm0Dj5CMq+11cwjBnsd-k_CVy6bQUeU4Jw@mail.gmail.com/T/#t
[2] https://lore.kernel.org/linux-mm/[email protected]/
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=adb72ae1915db28f934e9e02c18bfcea2f3ed3b7
[4] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=47227d27e2fcb01a9e8f5958d8997cf47a820afc
[5] https://bugzilla.kernel.org/show_bug.cgi?id=206337
[6] https://lore.kernel.org/linux-kselftest/[email protected]/
[7] https://lkml.org/lkml/2020/7/31/571David Gow (1):
mm: kasan: Do not panic if bothpanic_on_warnandkasan_multishotsetPatricia Alfonso (4):
Add KUnit Struct to Current Task
KUnit: KASAN IntegrationKASAN: Port KASAN Tests to KUnit KASAN: Testing DocumentationDocumentation/dev-tools/kasan.rst | 70 +++ include/kunit/test.h | 5 + include/linux/kasan.h | 6 + include/linux/sched.h | 4 + lib/Kconfig.kasan | 22 +- lib/Makefile | 7 +- lib/kasan_kunit.c | 770 +++++++++++++++++++++++++ lib/kunit/test.c | 13 +- lib/test_kasan.c | 903 ------------------------------ lib/test_kasan_module.c | 111 ++++ mm/kasan/report.c | 34 +- 11 files changed, 1028 insertions(+), 917 deletions(-) create mode 100644 lib/kasan_kunit.c delete mode 100644 lib/test_kasan.c create mode 100644 lib/test_kasan_module.c--
2.28.0.163.g6104cc2f0b6-goog