Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- tests/tcg/aarch64/bti-1.c | 62 +++++++++++++++++++++++++++ tests/tcg/aarch64/bti-crt.inc.c | 69 +++++++++++++++++++++++++++++++ tests/tcg/aarch64/Makefile.target | 3 ++ 3 files changed, 134 insertions(+) create mode 100644 tests/tcg/aarch64/bti-1.c create mode 100644 tests/tcg/aarch64/bti-crt.inc.c
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-crt.inc.c b/tests/tcg/aarch64/bti-crt.inc.c new file mode 100644 index 0000000000..bb363853de --- /dev/null +++ b/tests/tcg/aarch64/bti-crt.inc.c @@ -0,0 +1,69 @@ +/* + * Minimal user-environment for testing BTI. + * + * Normal libc is not built with BTI support enabled, and so could + * generate a BTI TRAP before ever reaching main. + */ + +#include <stdlib.h> +#include <signal.h> +#include <ucontext.h> +#include <asm/unistd.h> + +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"); +} + +/* + * Create the PT_NOTE that will enable BTI in the page tables. + * This will be created by the compiler with -mbranch-protection=standard, + * but as of 2019-03-29, this is has not been committed to gcc mainline. + * This will probably be in GCC10. + */ +asm(".section .note.gnu.property,\"a\"\n\ + .align 3\n\ + .long 4\n\ + .long 16\n\ + .long 5\n\ + .string \"GNU\"\n\ + .long 0xc0000000\n\ + .long 4\n\ + .long 1\n\ + .align 3\n\ + .previous"); diff --git a/tests/tcg/aarch64/Makefile.target b/tests/tcg/aarch64/Makefile.target index 2bb914975b..21da3bc37f 100644 --- a/tests/tcg/aarch64/Makefile.target +++ b/tests/tcg/aarch64/Makefile.target @@ -18,4 +18,7 @@ run-fcvt: fcvt AARCH64_TESTS += pauth-1 run-pauth-%: QEMU += -cpu max +AARCH64_TESTS += bti-1 +bti-1: LDFLAGS += -nostartfiles -nodefaultlibs -nostdlib + TESTS:=$(AARCH64_TESTS) -- 2.17.1