Test targeted address matching for exact and containing access ranges, adjacent ranges, zero-sized accesses, and boundary addresses at ULONG_MAX. These cases cover subtraction-based matching without runtime debugfs setup.
Signed-off-by: Hui Su <[email protected]> --- kernel/kcsan/selftest.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/kernel/kcsan/selftest.c b/kernel/kcsan/selftest.c index 84a1200271af..8da1ba2ba25a 100644 --- a/kernel/kcsan/selftest.c +++ b/kernel/kcsan/selftest.c @@ -12,6 +12,7 @@ #include <linux/init.h> #include <linux/kcsan-checks.h> #include <linux/kernel.h> +#include <linux/limits.h> #include <linux/printk.h> #include <linux/random.h> #include <linux/sched.h> @@ -101,6 +102,33 @@ static bool __init test_matching_access(void) return true; } +/* Test whether an access contains the selected target byte. */ +static bool __init test_target_matching(void) +{ + const unsigned long target = 0x1004; + + if (WARN_ON(!kcsan_target_matches(target, 0x1004, 1))) + return false; + if (WARN_ON(!kcsan_target_matches(target, 0x1000, 8))) + return false; + if (WARN_ON(kcsan_target_matches(target, 0x1000, 4))) + return false; + if (WARN_ON(kcsan_target_matches(target, 0x1005, 1))) + return false; + if (WARN_ON(kcsan_target_matches(target, 0x1004, 0))) + return false; + if (WARN_ON(!kcsan_target_matches(ULONG_MAX, ULONG_MAX, 1))) + return false; + if (WARN_ON(!kcsan_target_matches(ULONG_MAX, ULONG_MAX - 3, 4))) + return false; + if (WARN_ON(kcsan_target_matches(ULONG_MAX, ULONG_MAX - 1, 1))) + return false; + if (WARN_ON(kcsan_target_matches(0, ULONG_MAX - 1, 4))) + return false; + + return true; +} + /* * Correct memory barrier instrumentation is critical to avoiding false * positives: simple test to check at boot certain barriers are always properly @@ -251,6 +279,7 @@ static int __init kcsan_selftest(void) RUN_TEST(test_encode_decode); RUN_TEST(test_matching_access); + RUN_TEST(test_target_matching); RUN_TEST(test_barrier); pr_info("selftest: %d/%d tests passed\n", passed, total); -- 2.55.0
