<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/lib/kunit, branch v5.18</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.18</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.18'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2022-03-23T19:56:39Z</updated>
<entry>
<title>Merge tag 'linux-kselftest-kunit-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest</title>
<updated>2022-03-23T19:56:39Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-03-23T19:56:39Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d51b1b33c51d147b757f042b4d336603b699f362'/>
<id>urn:sha1:d51b1b33c51d147b757f042b4d336603b699f362</id>
<content type='text'>
Pull KUnit updates from Shuah Khan:

 - changes to decrease macro layering string, integer, EQ/NE asserts

 - remove unused macros

 - several cleanups and fixes

 - new list tests for list_del_init_careful(), list_is_head() and
   list_entry_is_head()

* tag 'linux-kselftest-kunit-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  list: test: Add a test for list_entry_is_head()
  list: test: Add a test for list_is_head()
  list: test: Add test for list_del_init_careful()
  kunit: cleanup assertion macro internal variables
  kunit: factor out str constants from binary assertion structs
  kunit: consolidate KUNIT_INIT_BINARY_ASSERT_STRUCT macros
  kunit: remove va_format from kunit_assert
  kunit: tool: drop mostly unused KunitResult.result field
  kunit: decrease macro layering for EQ/NE asserts
  kunit: decrease macro layering for integer asserts
  kunit: reduce layering in string assertion macros
  kunit: drop unused intermediate macros for ptr inequality checks
  kunit: make KUNIT_EXPECT_EQ() use KUNIT_EXPECT_EQ_MSG(), etc.
  kunit: drop unused assert_type from kunit_assert and clean up macros
  kunit: split out part of kunit_assert into a static const
  kunit: factor out kunit_base_assert_format() call into kunit_fail()
  kunit: drop unused kunit* field in kunit_assert
  kunit: move check if assertion passed into the macros
  kunit: add example test case showing off all the expect macros
</content>
</entry>
<entry>
<title>kunit: make kunit_test_timeout compatible with comment</title>
<updated>2022-03-22T22:57:11Z</updated>
<author>
<name>Peng Liu</name>
<email>liupeng256@huawei.com</email>
</author>
<published>2022-03-22T21:48:19Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=bdd015f7b71b92c2e4ecabac689642cc72553e04'/>
<id>urn:sha1:bdd015f7b71b92c2e4ecabac689642cc72553e04</id>
<content type='text'>
In function kunit_test_timeout, it is declared "300 * MSEC_PER_SEC"
represent 5min.  However, it is wrong when dealing with arm64 whose
default HZ = 250, or some other situations.  Use msecs_to_jiffies to fix
this, and kunit_test_timeout will work as desired.

Link: https://lkml.kernel.org/r/20220309083753.1561921-3-liupeng256@huawei.com
Fixes: 5f3e06208920 ("kunit: test: add support for test abort")
Signed-off-by: Peng Liu &lt;liupeng256@huawei.com&gt;
Reviewed-by: Marco Elver &lt;elver@google.com&gt;
Reviewed-by: Daniel Latypov &lt;dlatypov@google.com&gt;
Reviewed-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Tested-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Wang Kefeng &lt;wangkefeng.wang@huawei.com&gt;
Cc: David Gow &lt;davidgow@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kunit: fix UAF when run kfence test case test_gfpzero</title>
<updated>2022-03-22T22:57:11Z</updated>
<author>
<name>Peng Liu</name>
<email>liupeng256@huawei.com</email>
</author>
<published>2022-03-22T21:48:16Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=adf505457032c11b79b5a7c277c62ff5d61b17c2'/>
<id>urn:sha1:adf505457032c11b79b5a7c277c62ff5d61b17c2</id>
<content type='text'>
Patch series "kunit: fix a UAF bug and do some optimization", v2.

This series is to fix UAF (use after free) when running kfence test case
test_gfpzero, which is time costly.  This UAF bug can be easily triggered
by setting CONFIG_KFENCE_NUM_OBJECTS = 65535.  Furthermore, some
optimization for kunit tests has been done.

This patch (of 3):

Kunit will create a new thread to run an actual test case, and the main
process will wait for the completion of the actual test thread until
overtime.  The variable "struct kunit test" has local property in function
kunit_try_catch_run, and will be used in the test case thread.  Task
kunit_try_catch_run will free "struct kunit test" when kunit runs
overtime, but the actual test case is still run and an UAF bug will be
triggered.

The above problem has been both observed in a physical machine and qemu
platform when running kfence kunit tests.  The problem can be triggered
when setting CONFIG_KFENCE_NUM_OBJECTS = 65535.  Under this setting, the
test case test_gfpzero will cost hours and kunit will run to overtime.
The follows show the panic log.

  BUG: unable to handle page fault for address: ffffffff82d882e9

  Call Trace:
   kunit_log_append+0x58/0xd0
   ...
   test_alloc.constprop.0.cold+0x6b/0x8a [kfence_test]
   test_gfpzero.cold+0x61/0x8ab [kfence_test]
   kunit_try_run_case+0x4c/0x70
   kunit_generic_run_threadfn_adapter+0x11/0x20
   kthread+0x166/0x190
   ret_from_fork+0x22/0x30
  Kernel panic - not syncing: Fatal exception
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
  Ubuntu-1.8.2-1ubuntu1 04/01/2014

To solve this problem, the test case thread should be stopped when the
kunit frame runs overtime.  The stop signal will send in function
kunit_try_catch_run, and test_gfpzero will handle it.

Link: https://lkml.kernel.org/r/20220309083753.1561921-1-liupeng256@huawei.com
Link: https://lkml.kernel.org/r/20220309083753.1561921-2-liupeng256@huawei.com
Signed-off-by: Peng Liu &lt;liupeng256@huawei.com&gt;
Reviewed-by: Marco Elver &lt;elver@google.com&gt;
Reviewed-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Tested-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Wang Kefeng &lt;wangkefeng.wang@huawei.com&gt;
Cc: Daniel Latypov &lt;dlatypov@google.com&gt;
Cc: David Gow &lt;davidgow@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kunit: factor out str constants from binary assertion structs</title>
<updated>2022-01-31T18:55:39Z</updated>
<author>
<name>Daniel Latypov</name>
<email>dlatypov@google.com</email>
</author>
<published>2022-01-25T21:00:11Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2b6861e2372bac68861c54372f68f6016a7484fc'/>
<id>urn:sha1:2b6861e2372bac68861c54372f68f6016a7484fc</id>
<content type='text'>
If the compiler doesn't optimize them away, each kunit assertion (use of
KUNIT_EXPECT_EQ, etc.) can use 88 bytes of stack space in the worst and
most common case. This has led to compiler warnings and a suggestion
from Linus to move data from the structs into static const's where
possible [1].

This builds upon [2] which did so for the base struct kunit_assert type.
That only reduced sizeof(struct kunit_binary_assert) from 88 to 64.

Given these are by far the most commonly used asserts, this patch
factors out the textual representations of the operands and comparator
into another static const, saving 16 more bytes.

In detail, KUNIT_EXPECT_EQ(test, 2 + 2, 5) yields the following struct
  (struct kunit_binary_assert) {
    .assert = &lt;struct kunit_assert&gt;,
    .operation = "==",
    .left_text = "2 + 2",
    .left_value = 4,
    .right_text = "5",
    .right_value = 5,
  }
After this change
  static const struct kunit_binary_assert_text __text = {
    .operation = "==",
    .left_text = "2 + 2",
    .right_text = "5",
  };
  (struct kunit_binary_assert) {
    .assert = &lt;struct kunit_assert&gt;,
    .text = &amp;__text,
    .left_value = 4,
    .right_value = 5,
  }

This also DRYs the code a bit more since these str fields were repeated
for the string and pointer versions of kunit_binary_assert.

Note: we could name the kunit_binary_assert_text fields left/right
instead of left_text/right_text. But that would require changing the
macros a bit since they have args called "left" and "right" which would
be substituted in `.left = #left` as `.2 + 2 = \"2 + 2\"`.

[1] https://groups.google.com/g/kunit-dev/c/i3fZXgvBrfA/m/VULQg1z6BAAJ
[2] https://lore.kernel.org/linux-kselftest/20220113165931.451305-6-dlatypov@google.com/

Signed-off-by: Daniel Latypov &lt;dlatypov@google.com&gt;
Reviewed-by: David Gow &lt;davidgow@google.com&gt;
Reviewed-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>kunit: remove va_format from kunit_assert</title>
<updated>2022-01-31T18:55:27Z</updated>
<author>
<name>Daniel Latypov</name>
<email>dlatypov@google.com</email>
</author>
<published>2022-01-25T21:00:09Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=6419abb80e82c603bbec6d7f5af6c2f79fa5c4ae'/>
<id>urn:sha1:6419abb80e82c603bbec6d7f5af6c2f79fa5c4ae</id>
<content type='text'>
The concern is that having a lot of redundant fields in kunit_assert can
blow up stack usage if the compiler doesn't optimize them away [1].

The comment on this field implies that it was meant to be initialized
when the expect/assert was declared, but this only happens when we run
kunit_do_failed_assertion().

We don't need to access it outside of that function, so move it out of
the struct and make it a local variable there.

This change also takes the chance to reduce the number of macros by
inlining the now simplified KUNIT_INIT_ASSERT_STRUCT() macro.

[1] https://groups.google.com/g/kunit-dev/c/i3fZXgvBrfA/m/VULQg1z6BAAJ

Signed-off-by: Daniel Latypov &lt;dlatypov@google.com&gt;
Reviewed-by: David Gow &lt;davidgow@google.com&gt;
Reviewed-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>kunit: split out part of kunit_assert into a static const</title>
<updated>2022-01-25T19:49:59Z</updated>
<author>
<name>Daniel Latypov</name>
<email>dlatypov@google.com</email>
</author>
<published>2022-01-13T16:59:30Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=21957f90b28f6bc118c055e3e564d45f6e4df45d'/>
<id>urn:sha1:21957f90b28f6bc118c055e3e564d45f6e4df45d</id>
<content type='text'>
This is per Linus's suggestion in [1].

The issue there is that every KUNIT_EXPECT/KUNIT_ASSERT puts a
kunit_assert object onto the stack. Normally we rely on compilers to
elide this, but when that doesn't work out, this blows up the stack
usage of kunit test functions.

We can move some data off the stack by making it static.
This change introduces a new `struct kunit_loc` to hold the file and
line number and then just passing assert_type (EXPECT or ASSERT) as an
argument.

In [1], it was suggested to also move out the format string as well, but
users could theoretically craft a format string at runtime, so we can't.

This change leaves a copy of `assert_type` in kunit_assert for now
because cleaning up all the macros to not pass it around is a bit more
involved.

Here's an example of the expanded code for KUNIT_FAIL():
if (__builtin_expect(!!(!(false)), 0)) {
  static const struct kunit_loc loc = { .file = ... };
  struct kunit_fail_assert __assertion = { .assert = { .type ...  };
  kunit_do_failed_assertion(test, &amp;loc, KUNIT_EXPECTATION, &amp;__assertion.assert, ...);
};

[1] https://groups.google.com/g/kunit-dev/c/i3fZXgvBrfA/m/VULQg1z6BAAJ

Signed-off-by: Daniel Latypov &lt;dlatypov@google.com&gt;
Suggested-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Reviewed-by: David Gow &lt;davidgow@google.com&gt;
Reviewed-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>kunit: factor out kunit_base_assert_format() call into kunit_fail()</title>
<updated>2022-01-25T19:49:53Z</updated>
<author>
<name>Daniel Latypov</name>
<email>dlatypov@google.com</email>
</author>
<published>2022-01-13T16:59:29Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=dd640d70874bd27fb081d444252677766321c32f'/>
<id>urn:sha1:dd640d70874bd27fb081d444252677766321c32f</id>
<content type='text'>
We call this function first thing for all the assertion `format()`
functions.
This is the part that prints the file and line number and assertion type
(EXPECTATION, ASSERTION).

Having it as part of the format functions lets us have the flexibility
to not print that information (or print it differently) for new
assertion types, but I think this we don't need that.

And in the future, we'd like to consider factoring that data (file,
line#, type) out of the kunit_assert struct and into a `static`
variable, as Linus suggested [1], so we'd need to extract it anyways.

[1] https://groups.google.com/g/kunit-dev/c/i3fZXgvBrfA/m/VULQg1z6BAAJ

Signed-off-by: Daniel Latypov &lt;dlatypov@google.com&gt;
Reviewed-by: David Gow &lt;davidgow@google.com&gt;
Reviewed-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>kunit: move check if assertion passed into the macros</title>
<updated>2022-01-25T19:49:40Z</updated>
<author>
<name>Daniel Latypov</name>
<email>dlatypov@google.com</email>
</author>
<published>2022-01-13T16:59:27Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4fdacef8ac5a5382eeb1bc6fc2632d71a09d52cd'/>
<id>urn:sha1:4fdacef8ac5a5382eeb1bc6fc2632d71a09d52cd</id>
<content type='text'>
Currently the code always calls kunit_do_assertion() even though it does
nothing when `pass` is true.

This change moves the `if(!(pass))` check into the macro instead
and renames the function to kunit_do_failed_assertion().
I feel this a bit easier to read and understand.

This has the potential upside of avoiding a function call that does
nothing most of the time (assuming your tests are passing) but comes
with the downside of generating a bit more code and branches. We try to
mitigate the branches by tagging them with `unlikely()`.

This also means we don't have to initialize structs that we don't need,
which will become a tiny bit more expensive if we switch over to using
static variables to try and reduce stack usage. (There's runtime code
to check if the variable has been initialized yet or not).

Signed-off-by: Daniel Latypov &lt;dlatypov@google.com&gt;
Reviewed-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Reviewed-by: David Gow &lt;davidgow@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>kunit: add example test case showing off all the expect macros</title>
<updated>2022-01-25T19:49:20Z</updated>
<author>
<name>Daniel Latypov</name>
<email>dlatypov@google.com</email>
</author>
<published>2022-01-13T16:59:26Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7b3391057fa1921ba84ef17852a6998c0af27e4d'/>
<id>urn:sha1:7b3391057fa1921ba84ef17852a6998c0af27e4d</id>
<content type='text'>
Currently, these macros are only really documented near the bottom of
https://www.kernel.org/doc/html/latest/dev-tools/kunit/api/test.html#c.KUNIT_FAIL.

E.g. it's likely someone might just not realize that
KUNIT_EXPECT_STREQ() exists and instead use KUNIT_EXPECT_FALSE(strcmp())
or similar.

This can also serve as a basic smoketest that the KUnit assert machinery
still works for all the macros.

Signed-off-by: Daniel Latypov &lt;dlatypov@google.com&gt;
Reviewed-by: Brendan Higgins &lt;brendanhiggins@google.com&gt;
Reviewed-by: David Gow &lt;davidgow@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace</title>
<updated>2022-01-17T03:49:30Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-01-17T03:49:30Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=35ce8ae9ae2e471f92759f9d6880eab42cc1c3b6'/>
<id>urn:sha1:35ce8ae9ae2e471f92759f9d6880eab42cc1c3b6</id>
<content type='text'>
Pull signal/exit/ptrace updates from Eric Biederman:
 "This set of changes deletes some dead code, makes a lot of cleanups
  which hopefully make the code easier to follow, and fixes bugs found
  along the way.

  The end-game which I have not yet reached yet is for fatal signals
  that generate coredumps to be short-circuit deliverable from
  complete_signal, for force_siginfo_to_task not to require changing
  userspace configured signal delivery state, and for the ptrace stops
  to always happen in locations where we can guarantee on all
  architectures that the all of the registers are saved and available on
  the stack.

  Removal of profile_task_ext, profile_munmap, and profile_handoff_task
  are the big successes for dead code removal this round.

  A bunch of small bug fixes are included, as most of the issues
  reported were small enough that they would not affect bisection so I
  simply added the fixes and did not fold the fixes into the changes
  they were fixing.

  There was a bug that broke coredumps piped to systemd-coredump. I
  dropped the change that caused that bug and replaced it entirely with
  something much more restrained. Unfortunately that required some
  rebasing.

  Some successes after this set of changes: There are few enough calls
  to do_exit to audit in a reasonable amount of time. The lifetime of
  struct kthread now matches the lifetime of struct task, and the
  pointer to struct kthread is no longer stored in set_child_tid. The
  flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is
  removed. Issues where task-&gt;exit_code was examined with
  signal-&gt;group_exit_code should been examined were fixed.

  There are several loosely related changes included because I am
  cleaning up and if I don't include them they will probably get lost.

  The original postings of these changes can be found at:
     https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org
     https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org
     https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org

  I trimmed back the last set of changes to only the obviously correct
  once. Simply because there was less time for review than I had hoped"

* 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits)
  ptrace/m68k: Stop open coding ptrace_report_syscall
  ptrace: Remove unused regs argument from ptrace_report_syscall
  ptrace: Remove second setting of PT_SEIZED in ptrace_attach
  taskstats: Cleanup the use of task-&gt;exit_code
  exit: Use the correct exit_code in /proc/&lt;pid&gt;/stat
  exit: Fix the exit_code for wait_task_zombie
  exit: Coredumps reach do_group_exit
  exit: Remove profile_handoff_task
  exit: Remove profile_task_exit &amp; profile_munmap
  signal: clean up kernel-doc comments
  signal: Remove the helper signal_group_exit
  signal: Rename group_exit_task group_exec_task
  coredump: Stop setting signal-&gt;group_exit_task
  signal: Remove SIGNAL_GROUP_COREDUMP
  signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process
  signal: Make coredump handling explicit in complete_signal
  signal: Have prepare_signal detect coredumps using signal-&gt;core_state
  signal: Have the oom killer detect coredumps using signal-&gt;core_state
  exit: Move force_uaccess back into do_exit
  exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit
  ...
</content>
</entry>
</feed>
