[PATCH 08/15] selftests/seccomp: Convert HAVE_GETREG into ARCH_GETREG/ARCH_SETREG

Kees Cook
2020-09-12T11:11:36Z

Instead of special-casing the get/set-registers routines, move the
HAVE_GETREG logic into the new ARCH_GETREG() and ARCH_SETREG() macros.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
tools/testing/selftests/seccomp/seccomp_bpf.c | 27 ++++++++++---------
1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index 3b77bdbe7125..a986f2332327 100644
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -1821,20 +1821,21 @@ TEST_F(TRACE_poke, getpid_runs_normally)
} while (0)
#endif

-/* Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
+/*
+ * Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
* architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
*/
#if defined(__x86_64__) || defined(__i386__) || defined(__mips__)
-#define HAVE_GETREGS
+# define ARCH_GETREGS(_regs) ptrace(PTRACE_GETREGS, tracee, 0, &(_regs))
+# define ARCH_SETREGS(_regs) ptrace(PTRACE_SETREGS, tracee, 0, &(_regs))
#endif

/* Architecture-specific syscall fetching routine. */
int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
{
ARCH_REGS regs;
-#ifdef HAVE_GETREGS
- EXPECT_EQ(0, ptrace(PTRACE_GETREGS, tracee, 0, &regs)) {
- TH_LOG("PTRACE_GETREGS failed");
+#ifdef ARCH_GETREGS
+ EXPECT_EQ(0, ARCH_GETREGS(regs)) {
return -1;
}
#else
@@ -1855,17 +1856,19 @@ int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
void change_syscall(struct __test_metadata *_metadata,
pid_t tracee, int syscall, int result)
{
- int ret;
ARCH_REGS regs;
-#ifdef HAVE_GETREGS
- ret = ptrace(PTRACE_GETREGS, tracee, 0, &regs);
+#ifdef ARCH_GETREGS
+ EXPECT_EQ(0, ARCH_GETREGS(regs)) {
+ return;
+ }
#else
+ int ret;
struct iovec iov;
iov.iov_base = &regs;
iov.iov_len = sizeof(regs);
ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov);
-#endif
EXPECT_EQ(0, ret);
+#endif

SYSCALL_NUM_SET(regs, syscall);

@@ -1878,14 +1881,14 @@ void change_syscall(struct __test_metadata *_metadata,
#endif

/* Flush any register changes made. */
-#ifdef HAVE_GETREGS
- ret = ptrace(PTRACE_SETREGS, tracee, 0, &regs);
+#ifdef ARCH_SETREGS
+ EXPECT_EQ(0, ARCH_SETREGS(regs));
#else
iov.iov_base = &regs;
iov.iov_len = sizeof(regs);
ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov);
-#endif
EXPECT_EQ(0, ret);
+#endif
}

void tracer_seccomp(struct __test_metadata *_metadata, pid_t tracee,
--
2.25.1