[PATCH 0/2] riscv: Improve KASAN coverage to fix unit tests

From: Samuel Holland
Date: Wed Jul 31 2024 - 23:37:35 EST


This series fixes two areas where uninstrumented assembly routines
caused gaps in KASAN coverage on RISC-V, which were caught by KUnit
tests. The KASAN KUnit test suite passes after applying this series.

This series fixes the following test failures:
# kasan_strings: EXPECTATION FAILED at mm/kasan/kasan_test.c:1520
KASAN failure expected in "kasan_int_result = strcmp(ptr, "2")", but none occurred
# kasan_strings: EXPECTATION FAILED at mm/kasan/kasan_test.c:1524
KASAN failure expected in "kasan_int_result = strlen(ptr)", but none occurred
not ok 60 kasan_strings
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan_test.c:1531
KASAN failure expected in "set_bit(nr, addr)", but none occurred
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan_test.c:1533
KASAN failure expected in "clear_bit(nr, addr)", but none occurred
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan_test.c:1535
KASAN failure expected in "clear_bit_unlock(nr, addr)", but none occurred
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan_test.c:1536
KASAN failure expected in "__clear_bit_unlock(nr, addr)", but none occurred
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan_test.c:1537
KASAN failure expected in "change_bit(nr, addr)", but none occurred
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan_test.c:1543
KASAN failure expected in "test_and_set_bit(nr, addr)", but none occurred
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan_test.c:1545
KASAN failure expected in "test_and_set_bit_lock(nr, addr)", but none occurred
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan_test.c:1546
KASAN failure expected in "test_and_clear_bit(nr, addr)", but none occurred
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan_test.c:1548
KASAN failure expected in "test_and_change_bit(nr, addr)", but none occurred
not ok 61 kasan_bitops_generic


Samuel Holland (2):
riscv: Omit optimized string routines when using KASAN
riscv: Enable bitops instrumentation

arch/riscv/include/asm/bitops.h | 43 ++++++++++++++++++---------------
arch/riscv/include/asm/string.h | 2 ++
arch/riscv/kernel/riscv_ksyms.c | 3 ---
arch/riscv/lib/Makefile | 2 ++
arch/riscv/lib/strcmp.S | 1 +
arch/riscv/lib/strlen.S | 1 +
arch/riscv/lib/strncmp.S | 1 +
arch/riscv/purgatory/Makefile | 2 ++
8 files changed, 32 insertions(+), 23 deletions(-)

--
2.45.1