[PATCH 2/4] seccomp: add two missing ptrace ifdefines

Christian Brauner
2019-09-18T08:48:49Z

Add tw missing ptrace ifdefines to avoid compilation errors on systems
that do not provide PTRACE_EVENTMSG_SYSCALL_ENTRY or
PTRACE_EVENTMSG_SYSCALL_EXIT or:

gcc -Wl,-no-as-needed -Wall seccomp_bpf.c -lpthread -o seccomp_bpf
In file included from seccomp_bpf.c:52:0:
seccomp_bpf.c: In function ‘tracer_ptrace’:
seccomp_bpf.c:1792:20: error: ‘PTRACE_EVENTMSG_SYSCALL_ENTRY’ undeclared (first use in this function); did you mean ‘PTRACE_EVENT_CLONE’?
EXPECT_EQ(entry ? PTRACE_EVENTMSG_SYSCALL_ENTRY
^
../kselftest_harness.h:608:13: note: in definition of macro ‘__EXPECT’
__typeof__(_expected) __exp = (_expected); \
^~~~~~~~~
seccomp_bpf.c:1792:2: note: in expansion of macro ‘EXPECT_EQ’
EXPECT_EQ(entry ? PTRACE_EVENTMSG_SYSCALL_ENTRY
^~~~~~~~~
seccomp_bpf.c:1792:20: note: each undeclared identifier is reported only once for each function it appears in
EXPECT_EQ(entry ? PTRACE_EVENTMSG_SYSCALL_ENTRY
^
../kselftest_harness.h:608:13: note: in definition of macro ‘__EXPECT’
__typeof__(_expected) __exp = (_expected); \
^~~~~~~~~
seccomp_bpf.c:1792:2: note: in expansion of macro ‘EXPECT_EQ’
EXPECT_EQ(entry ? PTRACE_EVENTMSG_SYSCALL_ENTRY
^~~~~~~~~
seccomp_bpf.c:1793:6: error: ‘PTRACE_EVENTMSG_SYSCALL_EXIT’ undeclared (first use in this function); did you mean ‘PTRACE_EVENTMSG_SYSCALL_ENTRY’?
: PTRACE_EVENTMSG_SYSCALL_EXIT, msg);
^
../kselftest_harness.h:608:13: note: in definition of macro ‘__EXPECT’
__typeof__(_expected) __exp = (_expected); \
^~~~~~~~~
seccomp_bpf.c:1792:2: note: in expansion of macro ‘EXPECT_EQ’
EXPECT_EQ(entry ? PTRACE_EVENTMSG_SYSCALL_ENTRY
^~~~~~~~~

Fixes: 6a21cc50f0c7 ("seccomp: add a return code to trap to userspace")
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Tycho Andersen <tycho@tycho.ws>
CC: Tyler Hicks <tyhicks@canonical.com>
Cc: Jann Horn <jannh@google.com>
Cc: stable@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: bpf@vger.kernel.org
---
tools/testing/selftests/seccomp/seccomp_bpf.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index 6ef7f16c4cf5..ee52eab01800 100644
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -155,6 +155,14 @@ struct seccomp_data {
#ifndef PTRACE_SECCOMP_GET_METADATA
#define PTRACE_SECCOMP_GET_METADATA 0x420d

+#ifndef PTRACE_EVENTMSG_SYSCALL_ENTRY
+#define PTRACE_EVENTMSG_SYSCALL_ENTRY 1
+#endif
+
+#ifndef PTRACE_EVENTMSG_SYSCALL_EXIT
+#define PTRACE_EVENTMSG_SYSCALL_EXIT 2
+#endif
+
struct seccomp_metadata {
__u64 filter_off; /* Input: which filter */
__u64 flags; /* Output: filter's flags */
--
2.23.0