On Sun, Aug 23, 2026 at 12:51:48PM +0000, Bill Wendling wrote: > Add a KUnit test suite to verify the insertion and sorting of mappings > in struct uid_gid_map. This test suite validates both base extent > insertion (<= 5 mappings) and extended extent insertion (> 5 mappings, > which triggers the allocation of the forward and reverse pointers). > > This is especially useful for verifying that the __counted_by_ptr > attribute added to 'forward' and 'reverse' pointers works correctly > without causing any runtime bounds-checking panics or traps.
AFAIU patch 1 is supposed to not change any behavior. You could move the unit test to the front to make that clearer and also validate it. > Assisted-by: Gemini Next > Change-Id: If0c2c197a35cd7429cf0d2d6e3b33f0d9f0be66c Change-Id should not be used upstream. See Documentation/dev-tools/checkpatch.rst. > Signed-off-by: Bill Wendling <[email protected]> > --- > Cc: Kees Cook <[email protected]> > Cc: "Gustavo A. R. Silva" <[email protected]> > Cc: Christian Brauner <[email protected]> > Cc: Aleksa Sarai <[email protected]> > Cc: Jan Kara <[email protected]> > Cc: Nathan Chancellor <[email protected]> > Cc: Miguel Ojeda <[email protected]> > Cc: Thomas Gleixner <[email protected]> > Cc: Nicolas Schier <[email protected]> > Cc: Gary Guo <[email protected]> > Cc: "Thomas Weißschuh" <[email protected]> > Cc: Alice Ryhl <[email protected]> > Cc: Douglas Anderson <[email protected]> > Cc: Anand Moon <[email protected]> > Cc: Oleg Nesterov <[email protected]> > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > --- > init/Kconfig | 10 ++++ > kernel/.kunitconfig | 3 ++ > kernel/user_namespace.c | 4 ++ > kernel/user_namespace_kunit.c | 87 +++++++++++++++++++++++++++++++++++ > 4 files changed, 104 insertions(+) > create mode 100644 kernel/.kunitconfig > create mode 100644 kernel/user_namespace_kunit.c (...) > +static void test_user_ns_map_insert_extended(struct kunit *test) > +{ > + struct uid_gid_map map; > + struct uid_gid_extent extent; > + int i, ret; (...) > + /* Now sort the map to set up reverse mapping */ > + ret = sort_idmaps(&map); > + KUNIT_EXPECT_EQ(test, ret, 0); > + KUNIT_EXPECT_NOT_ERR_OR_NULL(test, map.reverse); KUNIT_EXPECT_*() will *not* abort the test when the assertion fails ... > + > + /* Verify sorting is correct */ > + for (i = 0; i < map.nr_extents; i++) { > + KUNIT_EXPECT_EQ(test, map.forward[i].count, 5); > + KUNIT_EXPECT_EQ(test, map.reverse[i].count, 5); ... leading to a crash here if map.reverse is invalid. To also abort the test on assertion failure use KUNIT_ASSERT_*(). > + } > + > + /* Clean up allocations to avoid leaks */ Pointless comment. This is true for every single call of kfree(). > + kfree(map.forward); > + kfree(map.reverse); > +} (...)
