[PATCH 09/15] selftests/seccomp: Convert REGSET calls into ARCH_GETREG/ARCH_SETREG

Kees Cook
2020-09-12T11:10:02Z

Consolidate the REGSET logic into the new ARCH_GETREG() and
ARCH_SETREG() macros, avoiding more #ifdef code in function bodies.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
tools/testing/selftests/seccomp/seccomp_bpf.c | 42 +++++++------------
1 file changed, 15 insertions(+), 27 deletions(-)

diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index a986f2332327..d9346121b89b 100644
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -1828,26 +1828,29 @@ TEST_F(TRACE_poke, getpid_runs_normally)
#if defined(__x86_64__) || defined(__i386__) || defined(__mips__)
# define ARCH_GETREGS(_regs) ptrace(PTRACE_GETREGS, tracee, 0, &(_regs))
# define ARCH_SETREGS(_regs) ptrace(PTRACE_SETREGS, tracee, 0, &(_regs))
+#else
+# define ARCH_GETREGS(_regs) ({ \
+ struct iovec __v; \
+ __v.iov_base = &(_regs); \
+ __v.iov_len = sizeof(_regs); \
+ ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &__v); \
+ })
+# define ARCH_SETREGS(_regs) ({ \
+ struct iovec __v; \
+ __v.iov_base = &(_regs); \
+ __v.iov_len = sizeof(_regs); \
+ ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &__v); \
+ })
#endif

/* Architecture-specific syscall fetching routine. */
int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
{
ARCH_REGS regs;
-#ifdef ARCH_GETREGS
- EXPECT_EQ(0, ARCH_GETREGS(regs)) {
- return -1;
- }
-#else
- struct iovec iov;

- iov.iov_base = &regs;
- iov.iov_len = sizeof(regs);
- EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) {
- TH_LOG("PTRACE_GETREGSET failed");
+ EXPECT_EQ(0, ARCH_GETREGS(regs)) {
return -1;
}
-#endif

return SYSCALL_NUM(regs);
}
@@ -1857,18 +1860,10 @@ void change_syscall(struct __test_metadata *_metadata,
pid_t tracee, int syscall, int result)
{
ARCH_REGS 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);
- EXPECT_EQ(0, ret);
-#endif

SYSCALL_NUM_SET(regs, syscall);

@@ -1881,14 +1876,7 @@ void change_syscall(struct __test_metadata *_metadata,
#endif

/* Flush any register changes made. */
-#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);
- EXPECT_EQ(0, ret);
-#endif
}

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