73 Commits

Author SHA1 Message Date
Thomas Weißschuh
3ad09d72e4 tools/nolibc: add testcase for fork()/waitpid()
On s390 the arguments to clone() which is used by fork() are different
than other archs.
Make sure everything works correctly.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-06-09 11:46:07 -07:00
Thomas Weißschuh
fddc8f81f1 tools/nolibc: use C89 comment syntax
Most of nolibc is already using C89 comments.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-06-09 11:46:07 -07:00
Thomas Weißschuh
7f291cfa90 tools/nolibc: use standard __asm__ statements
Most of the code was migrated to C99-conformant __asm__ statements
before. It seems string.h was missed.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-06-09 11:46:07 -07:00
Thomas Weißschuh
69f2cd9fea tools/nolibc: add testcases for vfprintf
vfprintf() is complex and so far did not have proper tests.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-06-09 11:33:05 -07:00
Willy Tarreau
2df07fc55d tools/nolibc: fix build of the test case using glibc
Some extra tests for various integer types and limits were added by
commit d1209597ff00 ("tools/nolibc: add tests for the integer limits
in stdint.h"), but we forgot to retest with glibc. Stddef and stdint
are now needed for the program to build there.

Cc: Vincent Dagonneau <v@vda.io>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-06-09 11:33:04 -07:00
Willy Tarreau
aa662d127e tools/nolibc: tests: fix build on non-c99 compliant compilers
Commit 9735716830f2 ("tools/nolibc: tests: add test for -fstack-protector")
brought a declaration inside the initialization statement of a for loop,
which breaks the build on compilers that do not default to c99
compatibility, making it more difficult to validate that the lib still
builds on such compilers. The fix is trivial, so let's move the
declaration to the variables block of the function instead. No backport
is needed.

Cc: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-06-09 11:33:04 -07:00
Thomas Weißschuh
e7654c3fbd tools/nolibc: tests: use volatile to force stack smashing
Use a volatile pointer to write outside the buffer so the compiler can't
optimize it away.

Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Link: https://lore.kernel.org/lkml/c0584807-511c-4496-b062-1263ea38f349@p183/
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-06-09 11:33:04 -07:00
Thomas Weißschuh
9735716830 tools/nolibc: tests: add test for -fstack-protector
Test the previously introduce stack protector functionality in nolibc.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-03-27 16:26:10 -07:00
Thomas Weißschuh
c4560bd806 tools/nolibc: tests: constify test_names
Nothing ever modifies this structure.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-03-27 16:26:10 -07:00
Willy Tarreau
3e2d337b94 selftests/nolibc: skip the chroot_root and link_dir tests when not privileged
These two tests always fail when the program is started natively as an
unprivileged user, and require the user to carefully check the output
of "make run-user" and ignore them.

Let's add an euid check and condition these two tests to euid==0. Now
the test case stops needlessly reporting failures. E.g.:

  $ make -C tools/testing/selftests/nolibc run-user
  ...
    CC      nolibc-test
  123 test(s) passed.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-03-20 08:45:22 -07:00
Vincent Dagonneau
d1209597ff tools/nolibc: add tests for the integer limits in stdint.h
This commit adds tests for the limits added in a previous commit. The
limits are defined in decimal in stdint.h and as hexadecimal in the
tests (e.g. 0x7f = 127 or 0x80 = -128). Hopefully it catches some of the
most egregious mistakes.

As we rely on the compiler to provide __SIZEOF_LONG__, we also test
whether it is defined.

Signed-off-by: Vincent Dagonneau <v@vda.io>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-03-20 08:45:22 -07:00
Vincent Dagonneau
a0994fb98d tools/nolibc: enlarge column width of tests
This commit enlarges the column width from 40 to 64 characters to make
room for longer tests

Signed-off-by: Vincent Dagonneau <v@vda.io>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-03-20 08:45:22 -07:00
Ammar Faizi
a290296ab8 selftests/nolibc: Add getpagesize(2) selftest
Test the getpagesize() function. Make sure it returns the correct
value.

Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-01-10 13:33:56 -08:00
Willy Tarreau
c80b5a0a22 selftests/nolibc: Add 7 tests for memcmp()
This adds 7 combinations of input values for memcmp() using signed and
unsigned bytes, which will trigger on the original code before Rasmus'
fix. This is mostly aimed at helping backporters verify their work, and
showing how tests for corner cases can be added to the selftests suite.

Before the fix it reports:
  12 memcmp_20_20 = 0                      [OK]
  13 memcmp_20_60 = -64                    [OK]
  14 memcmp_60_20 = 64                     [OK]
  15 memcmp_20_e0 = 64                    [FAIL]
  16 memcmp_e0_20 = -64                   [FAIL]
  17 memcmp_80_e0 = -96                    [OK]
  18 memcmp_e0_80 = 96                     [OK]

And after:
  12 memcmp_20_20 = 0                      [OK]
  13 memcmp_20_60 = -64                    [OK]
  14 memcmp_60_20 = 64                     [OK]
  15 memcmp_20_e0 = -192                   [OK]
  16 memcmp_e0_20 = 192                    [OK]
  17 memcmp_80_e0 = -96                    [OK]
  18 memcmp_e0_80 = 96                     [OK]

Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-10-28 15:17:22 -07:00
Willy Tarreau
1da02f5108 selftests/nolibc: support glibc as well
Adding support for glibc can be useful to distinguish between bugs in
nolibc and bugs in the kernel when a syscall reports an unusual value.

It's not that much work and should not affect the long term
maintainability of the tests. The necessary changes can essentially be
summed up like this:
  - set _GNU_SOURCE a the top to access some definitions
  - many includes added when we know we don't come from nolibc (missing
    the stdio include guard)
  - disable gettid() which is not exposed by glibc
  - disable gettimeofday's support of bad pointers since these  crash
    in glibc
  - add a simple itoa() for errorname(); strerror() is too verbose (no
    way to get short messages). strerrorname_np() was added in modern
    glibc (2.32) to do exactly this but that 's too recent to be usable
    as the default fallback.
  - use the standard ioperm() definition. May be we need to implement
    ioperm() in nolibc if that's useful.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00
Willy Tarreau
7172f1c685 selftests/nolibc: condition some tests on /proc existence
If /proc is not available (program run inside a chroot or without
sufficient permissions), it's better to disable the associated tests.
Some will be preserved like the ones which check for a failure to
create some entries there since they're still supposed to fail.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00
Willy Tarreau
1a5454f625 selftests/nolibc: recreate and populate /dev and /proc if missing
Most of the time the program will be run alone in an initramfs. There
is no value in requiring the user to populate /dev and /proc for such
tests, we can do it ourselves, and it participates to the tests at the
same time.

What's done here is that when called as init (getpid()==1) we check
if /dev exists or create it, if /dev/console and /dev/null exists,
otherwise we try to mount a devtmpfs there, and if it fails we fall
back to mknod. The console is reopened if stdout was closed. Finally
/proc is created and mounted if /proc/self cannot be found. This is
sufficient for most tests.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00
Willy Tarreau
aa73a86cda selftests/nolibc: on x86, support exiting with isa-debug-exit
QEMU, when started with "-device isa-debug-exit -no-reboot" will exit
with status code 2N+1 when N is written to 0x501. This is particularly
convenient for automated tests but this is not portable. As such we
only enable this on x86_64 when pid==1. In addition, this requires an
ioperm() call but in order not to have to define arch-specific syscalls
we just perform the syscall by hand there.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00
Willy Tarreau
f49896d7d9 selftests/nolibc: exit with poweroff on success when getpid() == 1
The idea is to ease automated testing under qemu. If the test succeeds
while running as PID 1, indicating the system was booted with init=/test,
let's just power off so that qemu can exit with a successful code. In
other situations it will exit and provoke a panic, which may be caught
for example with CONFIG_PVPANIC.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00
Willy Tarreau
95bc989488 selftests/nolibc: add a few tests for some libc functions
The test series called "stdlib" covers some libc functions (string,
stdlib etc). By default they are automatically run after "syscall"
but may be requested in argument or in variable NOLIBC_TEST.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00
Willy Tarreau
b4844fa0bd selftests/nolibc: implement a few tests for various syscalls
This adds 63 tests covering about 34 syscalls. Both successes and
failures are tested. Two tests fail when run as unprivileged user
(link_dir which returns EACCESS instead of EPERM, and chroot which
returns EPERM). One test (execve("/")) expects to fail on EACCESS,
but needs to have valid arguments otherwise the kernel will log a
message. And a few tests require /proc to be mounted.

The code is not pretty since all tests are one-liners, sometimes
resulting in long lines, especially when using compount statements to
preset a line, but it's convenient and doesn't obfuscate the code,
which is important to understand what failed.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00
Willy Tarreau
23da7bc923 selftests/nolibc: support a test definition format
It now becomes possible to pass a string either in argv[1] or in the
NOLIBC_TEST environment variable (the former having precedence), to
specify which tests to run. The format is:

   testname[:range]*[,testname...]

Where a range is either a single value or the min and max numbers of the
test IDs in a sequence, delimited by a dash. Multiple ranges are possible.
This should provide enough flexibility to focus on certain failing parts
just by playing with the boot command line in a boot loader or in qemu
depending on what is accessible.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00
Willy Tarreau
362aecb2d8 selftests/nolibc: add basic infrastructure to ease creation of nolibc tests
This creates a "nolibc" selftest that intends to test various parts of
the nolibc component, both in terms of build and execution for a given
architecture.

The aim is for it to be as simple to run as a kernel build, by just
passing the compiler (for the build) and the ARCH (for kernel and
execution).

It brings a basic squeleton made of a single C file that will ease testing
and error reporting. The code will be arranged so that it remains easy to
add basic tests for syscalls or library calls that may rely on a condition
to be executed, and whose result is compared to a value or to an error
with a specific errno value.

Tests will just use a relative line number in switch/case statements as
an index, saving the user from having to maintain arrays and complicated
functions which can often just be one-liners.

MAINTAINERS was updated.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00