tests: test_seccomp_validate: check for syscalls not in the filter

For each filter, we track which syscalls we have already seen, and at
the end we check for the ones we haven't seen.

Signed-off-by: Pablo Barbáchano <[email protected]>

Author: pb8o

tests/integration_tests/security/test_seccomp_validate.py

@@ -94,6 +94,9 @@ def test_validate_filter(seccompiler, bin_test_syscall, monkeypatch, tmp_path):
     fc_filter_path = Path(f"../resources/seccomp/{ARCH}-unknown-linux-musl.json")
     fc_filter = json.loads(fc_filter_path.read_text(encoding="ascii"))
 
+    # As of linux v6.12 both x786_64 and aarch64 are below this number
+    syscall_id_max = 512
+
     # cd to a tmp dir because we may generate a bunch of intermediate files
     monkeypatch.chdir(tmp_path)
     # prevent coredumps
@@ -105,14 +108,16 @@ def test_validate_filter(seccompiler, bin_test_syscall, monkeypatch, tmp_path):
     for thread, filter_data in fc_filter.items():
         filter_path = Path(f"{thread}.bpf")
         filter_path.write_bytes(filters[thread])
+        seen_syscalls = set()
         # for each rule, run the helper program and execute a syscall
         for rule in filter_data["filter"]:
             print(filter_path, rule)
             syscall = rule["syscall"]
+            syscall_id = seccomp.resolve_syscall(arch, syscall)
+            seen_syscalls.add(syscall_id)
             # this one cannot be called directly
             if syscall in ["rt_sigreturn"]:
                 continue
-            syscall_id = seccomp.resolve_syscall(arch, syscall)
             cmd = f"{bin_test_syscall} {filter_path} {syscall_id}"
             if "args" not in rule:
                 # syscall should be allowed with any arguments and exit 0
@@ -136,3 +141,11 @@ def test_validate_filter(seccompiler, bin_test_syscall, monkeypatch, tmp_path):
                     # if we call it with unallowed args, it should exit 159
                     # 159 = 128 (abnormal termination) + 31 (SIGSYS)
                     assert outcome.returncode == 159
+        print("now we test syscalls we didn't see in the filter")
+        for syscall_id in range(syscall_id_max):
+            if syscall_id in seen_syscalls:
+              continue
+            cmd = f"{bin_test_syscall} {filter_path} {syscall_id}"
+            print(cmd)
+            # and they should all exit 159
+            assert utils.run_cmd(cmd).returncode == 159