Files
linux/tools/testing/selftests/riscv/Makefile
Deepak Gupta d30c1683aa kselftest/riscv: add kselftest for user mode CFI
Add a kselftest for RISC-V control flow integrity implementation for
user mode. There is not a lot going on in the kernel to enable landing
pad for user mode. CFI selftests are intended to be compiled with a
zicfilp and zicfiss enabled compiler. This kselftest simply checks if
landing pads and shadow stacks for the process are enabled or not and
executes ptrace selftests on CFI. The selftest then registers a
SIGSEGV signal handler.  Any control flow violations are reported as
SIGSEGV with si_code = SEGV_CPERR.  The test will fail on receiving
any SEGV_CPERR. The shadow stack part has more changes in the kernel,
and thus there are separate tests for that.

- Exercise 'map_shadow_stack' syscall
- 'fork' test to make sure COW works for shadow stack pages
- gup tests
  Kernel uses FOLL_FORCE when access happens to memory via
  /proc/<pid>/mem. Not breaking that for shadow stack.
- signal test. Make sure signal delivery results in token creation on
  shadow stack and consumes (and verifies) token on sigreturn
- shadow stack protection test. attempts to write using regular store
  instruction on shadow stack memory must result in access faults
- ptrace test: adds landing pad violation, clears ELP and continues

In case the toolchain doesn't support the CFI extension, the CFI
kselftest won't be built.

Test output
===========

"""
TAP version 13
1..5
  This is to ensure shadow stack is indeed enabled and working
  This is to ensure shadow stack is indeed enabled and working
ok 1 shstk fork test
ok 2 map shadow stack syscall
ok 3 shadow stack gup tests
ok 4 shadow stack signal tests
ok 5 memory protections of shadow stack memory
"""

Suggested-by: Charlie Jenkins <charlie@rivosinc.com>
Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Signed-off-by: Deepak Gupta <debug@rivosinc.com>
Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6
Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com>
Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-28-b55691eacf4f@rivosinc.com
[pjw@kernel.org: updated to apply; cleaned up patch description, code comments]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29 02:38:40 -07:00

59 lines
1.4 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
# Originally tools/testing/arm64/Makefile
# When ARCH not overridden for crosscompiling, lookup machine
ARCH ?= $(shell uname -m 2>/dev/null || echo not)
ifneq (,$(filter $(ARCH),riscv))
RISCV_SUBTARGETS ?= abi hwprobe mm sigreturn vector cfi
else
RISCV_SUBTARGETS :=
endif
CFLAGS := -Wall -O2 -g
# A proper top_srcdir is needed by KSFT(lib.mk)
top_srcdir = $(realpath ../../../../)
# Additional include paths needed by kselftest.h and local headers
CFLAGS += -I$(top_srcdir)/tools/testing/selftests/
CFLAGS += $(KHDR_INCLUDES)
export CFLAGS
export top_srcdir
all:
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
mkdir -p $$BUILD_TARGET; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
install: all
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
run_tests: all
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
# Avoid any output on non riscv on emit_tests
emit_tests:
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
clean:
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
.PHONY: all clean install run_tests emit_tests