kernel/linux.git/lib/tests/printf_kunit.c, branch v6.18.21

vsprintf: Use %p4chR instead of %p4cn for reading data in reversed host ordering

2025-04-29T13:29:33+00:00

The generic FourCC format always prints the data using the big endian order. It is generic because it allows to read the data using a custom ordering. The current code uses "n" for reading data in the reverse host ordering. It makes the 4 variants [hnbl] consistent with the generic printing of IPv4 addresses. Unfortunately, it creates confusion on big endian systems. For example, it shows the data &(u32)0x67503030 as %p4cn 00Pg (0x30305067) But people expect that the ordering stays the same. The network ordering is a big-endian ordering. The problem is that the semantic is not the same. The modifiers affect the output ordering of IPv4 addresses while they affect the reading order in case of FourCC code. Avoid the confusion by replacing the "n" modifier with "hR", aka reverse host ordering. It is inspired by the existing %p[mM]R printf format. Reported-by: Geert Uytterhoeven Closes: https://lore.kernel.org/r/CAMuHMdV9tX=TG7E_CrSF=2PY206tXf+_yYRuacG48EWEtJLo-Q@mail.gmail.com Signed-off-by: Petr Mladek Acked-by: Alyssa Rosenzweig Reviewed-by: Geert Uytterhoeven Reviewed-by: Aditya Garg Link: https://lore.kernel.org/r/20250428123132.578771-1-pmladek@suse.com Signed-off-by: Alyssa Rosenzweig

printf: add tests for generic FourCCs

2025-04-21T14:18:30+00:00

This patch adds support for kunit tests of generic 32-bit FourCCs added to vsprintf. Acked-by: Tamir Duberstein Reviewed-by: Andy Shevchenko Reviewed-by: Petr Mladek Tested-by: Petr Mladek Signed-off-by: Aditya Garg Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/PN3PR01MB95973AF4F6262B2D1996FB25B8B52@PN3PR01MB9597.INDPRD01.PROD.OUTLOOK.COM Signed-off-by: Alyssa Rosenzweig

printf: implicate test line in failure messages

2025-03-13T17:26:33+00:00

This improves the failure output by pointing to the failing line at the top level of the test, e.g.: # test_number: EXPECTATION FAILED at lib/printf_kunit.c:103 lib/printf_kunit.c:167: vsnprintf(buf, 256, "%#-12x", ...) wrote '0x1234abcd ', expected '0x1234abce ' # test_number: EXPECTATION FAILED at lib/printf_kunit.c:142 lib/printf_kunit.c:167: kvasprintf(..., "%#-12x", ...) returned '0x1234abcd ', expected '0x1234abce ' Signed-off-by: Tamir Duberstein Reviewed-by: Petr Mladek Tested-by: Petr Mladek Link: https://lore.kernel.org/r/20250307-printf-kunit-convert-v6-3-4d85c361c241@gmail.com Signed-off-by: Kees Cook

printf: break kunit into test cases

2025-03-13T17:26:33+00:00

Move all tests into `printf_test_cases`. This gives us nicer output in the event of a failure. Combine `plain_format` and `plain_hash` into `hash_pointer` since they're testing the same scenario. Signed-off-by: Tamir Duberstein Reviewed-by: Petr Mladek Tested-by: Petr Mladek Link: https://lore.kernel.org/r/20250307-printf-kunit-convert-v6-2-4d85c361c241@gmail.com Signed-off-by: Kees Cook

printf: convert self-test to KUnit

2025-03-13T17:26:33+00:00

Convert the printf() self-test to a KUnit test. In the interest of keeping the patch reasonably-sized this doesn't refactor the tests into proper parameterized tests - it's all one big test case. Signed-off-by: Tamir Duberstein Reviewed-by: Petr Mladek Tested-by: Petr Mladek Link: https://lore.kernel.org/r/20250307-printf-kunit-convert-v6-1-4d85c361c241@gmail.com Signed-off-by: Kees Cook