From 6358890cb939192f6169fdf7664d903bf9b1d338 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 16 Oct 2020 11:42:07 -0700 Subject: tests/tcg/aarch64: Add bti smoke tests MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The note test requires gcc 10 for -mbranch-protection=standard. The mmap test uses PROT_BTI and does not require special compiler support. Acked-by: Alex Bennée Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-id: 20201016184207.786698-13-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- tests/tcg/aarch64/Makefile.target | 10 ++++ tests/tcg/aarch64/bti-1.c | 62 ++++++++++++++++++++++ tests/tcg/aarch64/bti-2.c | 108 ++++++++++++++++++++++++++++++++++++++ tests/tcg/aarch64/bti-crt.inc.c | 51 ++++++++++++++++++ tests/tcg/configure.sh | 4 ++ 5 files changed, 235 insertions(+) create mode 100644 tests/tcg/aarch64/bti-1.c create mode 100644 tests/tcg/aarch64/bti-2.c create mode 100644 tests/tcg/aarch64/bti-crt.inc.c diff --git a/tests/tcg/aarch64/Makefile.target b/tests/tcg/aarch64/Makefile.target index e7249915e7..d7d33e293c 100644 --- a/tests/tcg/aarch64/Makefile.target +++ b/tests/tcg/aarch64/Makefile.target @@ -25,6 +25,16 @@ run-pauth-%: QEMU_OPTS += -cpu max run-plugin-pauth-%: QEMU_OPTS += -cpu max endif +# BTI Tests +# bti-1 tests the elf notes, so we require special compiler support. +ifneq ($(DOCKER_IMAGE)$(CROSS_CC_HAS_ARMV8_BTI),) +AARCH64_TESTS += bti-1 +bti-1: CFLAGS += -mbranch-protection=standard +bti-1: LDFLAGS += -nostdlib +endif +# bti-2 tests PROT_BTI, so no special compiler support required. +AARCH64_TESTS += bti-2 + # Semihosting smoke test for linux-user AARCH64_TESTS += semihosting run-semihosting: semihosting diff --git a/tests/tcg/aarch64/bti-1.c b/tests/tcg/aarch64/bti-1.c new file mode 100644 index 0000000000..61924f0d7a --- /dev/null +++ b/tests/tcg/aarch64/bti-1.c @@ -0,0 +1,62 @@ +/* + * Branch target identification, basic notskip cases. + */ + +#include "bti-crt.inc.c" + +static void skip2_sigill(int sig, siginfo_t *info, ucontext_t *uc) +{ + uc->uc_mcontext.pc += 8; + uc->uc_mcontext.pstate = 1; +} + +#define NOP "nop" +#define BTI_N "hint #32" +#define BTI_C "hint #34" +#define BTI_J "hint #36" +#define BTI_JC "hint #38" + +#define BTYPE_1(DEST) \ + asm("mov %0,#1; adr x16, 1f; br x16; 1: " DEST "; mov %0,#0" \ + : "=r"(skipped) : : "x16") + +#define BTYPE_2(DEST) \ + asm("mov %0,#1; adr x16, 1f; blr x16; 1: " DEST "; mov %0,#0" \ + : "=r"(skipped) : : "x16", "x30") + +#define BTYPE_3(DEST) \ + asm("mov %0,#1; adr x15, 1f; br x15; 1: " DEST "; mov %0,#0" \ + : "=r"(skipped) : : "x15") + +#define TEST(WHICH, DEST, EXPECT) \ + do { WHICH(DEST); fail += skipped ^ EXPECT; } while (0) + + +int main() +{ + int fail = 0; + int skipped; + + /* Signal-like with SA_SIGINFO. */ + signal_info(SIGILL, skip2_sigill); + + TEST(BTYPE_1, NOP, 1); + TEST(BTYPE_1, BTI_N, 1); + TEST(BTYPE_1, BTI_C, 0); + TEST(BTYPE_1, BTI_J, 0); + TEST(BTYPE_1, BTI_JC, 0); + + TEST(BTYPE_2, NOP, 1); + TEST(BTYPE_2, BTI_N, 1); + TEST(BTYPE_2, BTI_C, 0); + TEST(BTYPE_2, BTI_J, 1); + TEST(BTYPE_2, BTI_JC, 0); + + TEST(BTYPE_3, NOP, 1); + TEST(BTYPE_3, BTI_N, 1); + TEST(BTYPE_3, BTI_C, 1); + TEST(BTYPE_3, BTI_J, 0); + TEST(BTYPE_3, BTI_JC, 0); + + return fail; +} diff --git a/tests/tcg/aarch64/bti-2.c b/tests/tcg/aarch64/bti-2.c new file mode 100644 index 0000000000..6dc8908b5a --- /dev/null +++ b/tests/tcg/aarch64/bti-2.c @@ -0,0 +1,108 @@ +/* + * Branch target identification, basic notskip cases. + */ + +#include +#include +#include +#include +#include + +#ifndef PROT_BTI +#define PROT_BTI 0x10 +#endif + +static void skip2_sigill(int sig, siginfo_t *info, void *vuc) +{ + ucontext_t *uc = vuc; + uc->uc_mcontext.pc += 8; + uc->uc_mcontext.pstate = 1; +} + +#define NOP "nop" +#define BTI_N "hint #32" +#define BTI_C "hint #34" +#define BTI_J "hint #36" +#define BTI_JC "hint #38" + +#define BTYPE_1(DEST) \ + "mov x1, #1\n\t" \ + "adr x16, 1f\n\t" \ + "br x16\n" \ +"1: " DEST "\n\t" \ + "mov x1, #0" + +#define BTYPE_2(DEST) \ + "mov x1, #1\n\t" \ + "adr x16, 1f\n\t" \ + "blr x16\n" \ +"1: " DEST "\n\t" \ + "mov x1, #0" + +#define BTYPE_3(DEST) \ + "mov x1, #1\n\t" \ + "adr x15, 1f\n\t" \ + "br x15\n" \ +"1: " DEST "\n\t" \ + "mov x1, #0" + +#define TEST(WHICH, DEST, EXPECT) \ + WHICH(DEST) "\n" \ + ".if " #EXPECT "\n\t" \ + "eor x1, x1," #EXPECT "\n" \ + ".endif\n\t" \ + "add x0, x0, x1\n\t" + +extern char test_begin[], test_end[]; + +asm("\n" +"test_begin:\n\t" + BTI_C "\n\t" + "mov x2, x30\n\t" + "mov x0, #0\n\t" + + TEST(BTYPE_1, NOP, 1) + TEST(BTYPE_1, BTI_N, 1) + TEST(BTYPE_1, BTI_C, 0) + TEST(BTYPE_1, BTI_J, 0) + TEST(BTYPE_1, BTI_JC, 0) + + TEST(BTYPE_2, NOP, 1) + TEST(BTYPE_2, BTI_N, 1) + TEST(BTYPE_2, BTI_C, 0) + TEST(BTYPE_2, BTI_J, 1) + TEST(BTYPE_2, BTI_JC, 0) + + TEST(BTYPE_3, NOP, 1) + TEST(BTYPE_3, BTI_N, 1) + TEST(BTYPE_3, BTI_C, 1) + TEST(BTYPE_3, BTI_J, 0) + TEST(BTYPE_3, BTI_JC, 0) + + "ret x2\n" +"test_end:" +); + +int main() +{ + struct sigaction sa; + + void *p = mmap(0, getpagesize(), + PROT_EXEC | PROT_READ | PROT_WRITE | PROT_BTI, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (p == MAP_FAILED) { + perror("mmap"); + return 1; + } + + memset(&sa, 0, sizeof(sa)); + sa.sa_sigaction = skip2_sigill; + sa.sa_flags = SA_SIGINFO; + if (sigaction(SIGILL, &sa, NULL) < 0) { + perror("sigaction"); + return 1; + } + + memcpy(p, test_begin, test_end - test_begin); + return ((int (*)(void))p)(); +} diff --git a/tests/tcg/aarch64/bti-crt.inc.c b/tests/tcg/aarch64/bti-crt.inc.c new file mode 100644 index 0000000000..47805f4e35 --- /dev/null +++ b/tests/tcg/aarch64/bti-crt.inc.c @@ -0,0 +1,51 @@ +/* + * Minimal user-environment for testing BTI. + * + * Normal libc is not (yet) built with BTI support enabled, + * and so could generate a BTI TRAP before ever reaching main. + */ + +#include +#include +#include +#include + +int main(void); + +void _start(void) +{ + exit(main()); +} + +void exit(int ret) +{ + register int x0 __asm__("x0") = ret; + register int x8 __asm__("x8") = __NR_exit; + + asm volatile("svc #0" : : "r"(x0), "r"(x8)); + __builtin_unreachable(); +} + +/* + * Irritatingly, the user API struct sigaction does not match the + * kernel API struct sigaction. So for simplicity, isolate the + * kernel ABI here, and make this act like signal. + */ +void signal_info(int sig, void (*fn)(int, siginfo_t *, ucontext_t *)) +{ + struct kernel_sigaction { + void (*handler)(int, siginfo_t *, ucontext_t *); + unsigned long flags; + unsigned long restorer; + unsigned long mask; + } sa = { fn, SA_SIGINFO, 0, 0 }; + + register int x0 __asm__("x0") = sig; + register void *x1 __asm__("x1") = &sa; + register void *x2 __asm__("x2") = 0; + register int x3 __asm__("x3") = sizeof(unsigned long); + register int x8 __asm__("x8") = __NR_rt_sigaction; + + asm volatile("svc #0" + : : "r"(x0), "r"(x1), "r"(x2), "r"(x3), "r"(x8) : "memory"); +} diff --git a/tests/tcg/configure.sh b/tests/tcg/configure.sh index be51bdb5a4..e1b70e25f2 100755 --- a/tests/tcg/configure.sh +++ b/tests/tcg/configure.sh @@ -240,6 +240,10 @@ for target in $target_list; do -march=armv8.3-a -o $TMPE $TMPC; then echo "CROSS_CC_HAS_ARMV8_3=y" >> $config_target_mak fi + if do_compiler "$target_compiler" $target_compiler_cflags \ + -mbranch-protection=standard -o $TMPE $TMPC; then + echo "CROSS_CC_HAS_ARMV8_BTI=y" >> $config_target_mak + fi ;; esac -- cgit v1.2.3