Merge patch series "riscv: Improve KASAN coverage to fix unit tests"

Samuel Holland <samuel.holland@sifive.com> says:

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(-)

* b4-shazam-merge:
  riscv: Enable bitops instrumentation
  riscv: Omit optimized string routines when using KASAN

Link: https://lore.kernel.org/r/20240801033725.28816-1-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

4 files changed, 5 insertions, 0 deletions

diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile
index 2b369f51b0a5..8eec6b69a875 100644
--- a/arch/riscv/lib/Makefile
+++ b/arch/riscv/lib/Makefile
@@ -3,9 +3,11 @@ lib-y			+= delay.o
 lib-y			+= memcpy.o
 lib-y			+= memset.o
 lib-y			+= memmove.o
+ifeq ($(CONFIG_KASAN_GENERIC)$(CONFIG_KASAN_SW_TAGS),)
 lib-y			+= strcmp.o
 lib-y			+= strlen.o
 lib-y			+= strncmp.o
+endif
 lib-y			+= csum.o
 ifeq ($(CONFIG_MMU), y)
 lib-$(CONFIG_RISCV_ISA_V)	+= uaccess_vector.o
diff --git a/arch/riscv/lib/strcmp.S b/arch/riscv/lib/strcmp.S
index bc73325b2fd1..57a5c0066231 100644
--- a/arch/riscv/lib/strcmp.S
+++ b/arch/riscv/lib/strcmp.S
@@ -121,3 +121,4 @@ strcmp_zbb:
 #endif
 SYM_FUNC_END(strcmp)
 SYM_FUNC_ALIAS(__pi_strcmp, strcmp)
+EXPORT_SYMBOL(strcmp)
diff --git a/arch/riscv/lib/strlen.S b/arch/riscv/lib/strlen.S
index 8ae3064e45ff..962983b73251 100644
--- a/arch/riscv/lib/strlen.S
+++ b/arch/riscv/lib/strlen.S
@@ -131,3 +131,4 @@ strlen_zbb:
 #endif
 SYM_FUNC_END(strlen)
 SYM_FUNC_ALIAS(__pi_strlen, strlen)
+EXPORT_SYMBOL(strlen)
diff --git a/arch/riscv/lib/strncmp.S b/arch/riscv/lib/strncmp.S
index b36325a57f6a..7b2d0ff9ed6c 100644
--- a/arch/riscv/lib/strncmp.S
+++ b/arch/riscv/lib/strncmp.S
@@ -137,3 +137,4 @@ strncmp_zbb:
 #endif
 SYM_FUNC_END(strncmp)
 SYM_FUNC_ALIAS(__pi_strncmp, strncmp)
+EXPORT_SYMBOL(strncmp)