On Fri, May 13, 2022 at 04:32:11PM +0800, David Gow wrote: > Most in-kernel tests (such as KUnit tests) are not supposed to run on > production systems: they may do deliberately illegal things to trigger > errors, and have security implications (for example, KUnit assertions > will often deliberately leak kernel addresses). > > Add a new taint type, TAINT_TEST to signal that a test has been run. > This will be printed as 'N' (originally for kuNit, as every other > sensible letter was taken.) > > This should discourage people from running these tests on production > systems, and to make it easier to tell if tests have been run > accidentally (by loading the wrong configuration, etc.) > > Signed-off-by: David Gow <davidgow@xxxxxxxxxx> > --- > > Updated this to handle the most common case of selftest modules, in > addition to KUnit tests. There's room for other tests or test frameworks > to use this as well, either with a call to add_taint() from within the > kernel, or by writing to /proc/sys/kernel/tainted. > > The 'N' character for the taint is even less useful now that it's no > longer short for kuNit, but all the letters in TEST are taken. :-( > > Changes since v2: > https://lore.kernel.org/linux-kselftest/20220430030019.803481-1-davidgow@xxxxxxxxxx/ > - Rename TAINT_KUNIT -> TAINT_TEST. > - Split into separate patches for adding the taint, and triggering it. > - Taint on a kselftest_module being loaded (patch 3/3) > > Changes since v1: > https://lore.kernel.org/linux-kselftest/20220429043913.626647-1-davidgow@xxxxxxxxxx/ > - Make the taint per-module, to handle the case when tests are in > (longer lasting) modules. (Thanks Greg KH). > > Note that this still has checkpatch.pl warnings around bracket > placement, which are intentional as part of matching the surrounding > code. > > --- > Documentation/admin-guide/tainted-kernels.rst | 1 + > include/linux/panic.h | 3 ++- > kernel/panic.c | 1 + > 3 files changed, 4 insertions(+), 1 deletion(-) > > diff --git a/Documentation/admin-guide/tainted-kernels.rst b/Documentation/admin-guide/tainted-kernels.rst > index ceeed7b0798d..546f3071940d 100644 > --- a/Documentation/admin-guide/tainted-kernels.rst > +++ b/Documentation/admin-guide/tainted-kernels.rst > @@ -100,6 +100,7 @@ Bit Log Number Reason that got the kernel tainted > 15 _/K 32768 kernel has been live patched > 16 _/X 65536 auxiliary taint, defined for and used by distros > 17 _/T 131072 kernel was built with the struct randomization plugin > + 18 _/N 262144 an in-kernel test (such as a KUnit test) has been run I think mentioning just kunit fuzzes its interpretation here. Best to keep that out. Other than that: Acked-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> Luis
