On Wed, 15 Oct 2025 at 15:23, Florian Schmaus florian.schmaus@codasip.com wrote:
The previous implementation incorrectly assumed the original type of 'priv' was void**, leading to an unnecessary and misleading cast. Correct the cast of the 'priv' pointer in test_dev_action() to its actual type, long*, removing an unnecessary cast.
As an additional benefit, this fixes an out-of-bounds CHERI fault on hardware with architectural capabilities. The original implementation tried to store a capability-sized pointer using the 'priv' pointer. However, the 'priv' pointer's capability only granted access to the memory region of its original long type, leading to a bounds violation since the size of a long is smaller than the size of a capability. This change ensures that the pointer usage respects the capabilities' bounds.
Signed-off-by: Florian Schmaus florian.schmaus@codasip.com
Thanks for this.
One simple formatting issue below, otherwise this is fine.
Also, it'd be good to add a 'Fixes' tag: Fixes: d03c720e03bd ("kunit: Add APIs for managing devices")
Reviewed-by: David Gow davidgow@google.com
Cheers, -- David
lib/kunit/kunit-test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c index 8c01eabd4eaf..957b67818489 100644 --- a/lib/kunit/kunit-test.c +++ b/lib/kunit/kunit-test.c @@ -739,7 +739,7 @@ static struct kunit_case kunit_current_test_cases[] = {
static void test_dev_action(void *priv) {
*(void **)priv = (void *)1;
*(long*)priv = 1;
checkpatch whinges here: ERROR: "(foo*)" should be "(foo *)" #39: FILE: lib/kunit/kunit-test.c:742: + *(long*)priv = 1;
}
static void kunit_device_test(struct kunit *test)
2.51.0