On Thu, 23 May 2024 14:11:48 +0200
Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
> Adding uretprobe shadow stack test that runs all existing
> uretprobe tests with shadow stack enabled if it's available.
>
According to the document and sample code, this looks good to me.
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Thanks,
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
> .../selftests/bpf/prog_tests/uprobe_syscall.c | 60 +++++++++++++++++++
> 1 file changed, 60 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
> index 3ef324c2db50..fda456401284 100644
> --- a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
> +++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
> @@ -9,6 +9,9 @@
> #include <linux/compiler.h>
> #include <linux/stringify.h>
> #include <sys/wait.h>
> +#include <sys/syscall.h>
> +#include <sys/prctl.h>
> +#include <asm/prctl.h>
> #include "uprobe_syscall.skel.h"
> #include "uprobe_syscall_executed.skel.h"
>
> @@ -297,6 +300,56 @@ static void test_uretprobe_syscall_call(void)
> close(go[1]);
> close(go[0]);
> }
> +
> +/*
> + * Borrowed from tools/testing/selftests/x86/test_shadow_stack.c.
> + *
> + * For use in inline enablement of shadow stack.
> + *
> + * The program can't return from the point where shadow stack gets enabled
> + * because there will be no address on the shadow stack. So it can't use
> + * syscall() for enablement, since it is a function.
> + *
> + * Based on code from nolibc.h. Keep a copy here because this can't pull
> + * in all of nolibc.h.
> + */
> +#define ARCH_PRCTL(arg1, arg2) \
> +({ \
> + long _ret; \
> + register long _num asm("eax") = __NR_arch_prctl; \
> + register long _arg1 asm("rdi") = (long)(arg1); \
> + register long _arg2 asm("rsi") = (long)(arg2); \
> + \
> + asm volatile ( \
> + "syscall\n" \
> + : "=a"(_ret) \
> + : "r"(_arg1), "r"(_arg2), \
> + "0"(_num) \
> + : "rcx", "r11", "memory", "cc" \
> + ); \
> + _ret; \
> +})
> +
> +#ifndef ARCH_SHSTK_ENABLE
> +#define ARCH_SHSTK_ENABLE 0x5001
> +#define ARCH_SHSTK_DISABLE 0x5002
> +#define ARCH_SHSTK_SHSTK (1ULL << 0)
> +#endif
> +
> +static void test_uretprobe_shadow_stack(void)
> +{
> + if (ARCH_PRCTL(ARCH_SHSTK_ENABLE, ARCH_SHSTK_SHSTK)) {
> + test__skip();
> + return;
> + }
> +
> + /* Run all of the uretprobe tests. */
> + test_uretprobe_regs_equal();
> + test_uretprobe_regs_change();
> + test_uretprobe_syscall_call();
> +
> + ARCH_PRCTL(ARCH_SHSTK_DISABLE, ARCH_SHSTK_SHSTK);
> +}
> #else
> static void test_uretprobe_regs_equal(void)
> {
> @@ -312,6 +365,11 @@ static void test_uretprobe_syscall_call(void)
> {
> test__skip();
> }
> +
> +static void test_uretprobe_shadow_stack(void)
> +{
> + test__skip();
> +}
> #endif
>
> void test_uprobe_syscall(void)
> @@ -322,4 +380,6 @@ void test_uprobe_syscall(void)
> test_uretprobe_regs_change();
> if (test__start_subtest("uretprobe_syscall_call"))
> test_uretprobe_syscall_call();
> + if (test__start_subtest("uretprobe_shadow_stack"))
> + test_uretprobe_shadow_stack();
> }
> --
> 2.45.1
>
--
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
