selftests/seccomp: Check ENOSYS under tracing

There should be no difference between -1 and other negative syscalls
while tracing.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: Will Deacon <will@kernel.org>
Cc: Keno Fischer <keno@juliacomputing.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
This commit is contained in:
Kees Cook 2020-07-04 23:12:32 -07:00 committed by Shuah Khan
parent 0bf18a0cdc
commit 4c6614dc86
1 changed files with 26 additions and 0 deletions

View File

@ -1903,6 +1903,32 @@ FIXTURE_TEARDOWN(TRACE_syscall)
teardown_trace_fixture(_metadata, self->tracer);
}
TEST(negative_ENOSYS)
{
/* Untraced negative syscalls should return ENOSYS. */
errno = 0;
EXPECT_EQ(-1, syscall(-1));
EXPECT_EQ(errno, ENOSYS);
errno = 0;
EXPECT_EQ(-1, syscall(-101));
EXPECT_EQ(errno, ENOSYS);
}
TEST_F(TRACE_syscall, negative_ENOSYS)
{
/*
* There should be no difference between an "internal" skip
* and userspace asking for syscall "-1".
*/
errno = 0;
EXPECT_EQ(-1, syscall(-1));
EXPECT_EQ(errno, ENOSYS);
/* And no difference for "still not valid but not -1". */
errno = 0;
EXPECT_EQ(-1, syscall(-101));
EXPECT_EQ(errno, ENOSYS);
}
TEST_F(TRACE_syscall, syscall_allowed)
{
/* getppid works as expected (no changes). */