#define SECCOMP_MODE_FILTER 2
#endif
-#ifndef SECCOMP_RET_KILL
-#define SECCOMP_RET_KILL 0x00000000U /* kill the task immediately */
-#define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */
-#define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */
-#define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */
-#define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */
-
-/* Masks for the return value sections. */
-#define SECCOMP_RET_ACTION 0x7fff0000U
-#define SECCOMP_RET_DATA 0x0000ffffU
-
+#ifndef SECCOMP_RET_ALLOW
struct seccomp_data {
int nr;
__u32 arch;
};
#endif
+#ifndef SECCOMP_RET_KILL_PROCESS
+#define SECCOMP_RET_KILL_PROCESS 0x80000000U /* kill the process */
+#define SECCOMP_RET_KILL_THREAD 0x00000000U /* kill the thread */
+#endif
+#ifndef SECCOMP_RET_KILL
+#define SECCOMP_RET_KILL SECCOMP_RET_KILL_THREAD
+#define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */
+#define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */
+#define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */
+#define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */
+#endif
+#ifndef SECCOMP_RET_LOG
+#define SECCOMP_RET_LOG 0x7ffc0000U /* allow after logging */
+#endif
+
+#ifndef __NR_seccomp
+# if defined(__i386__)
+# define __NR_seccomp 354
+# elif defined(__x86_64__)
+# define __NR_seccomp 317
+# elif defined(__arm__)
+# define __NR_seccomp 383
+# elif defined(__aarch64__)
+# define __NR_seccomp 277
+# elif defined(__hppa__)
+# define __NR_seccomp 338
+# elif defined(__powerpc__)
+# define __NR_seccomp 358
+# elif defined(__s390__)
+# define __NR_seccomp 348
+# else
+# warning "seccomp syscall number unknown for this architecture"
+# define __NR_seccomp 0xffff
+# endif
+#endif
+
+#ifndef SECCOMP_SET_MODE_STRICT
+#define SECCOMP_SET_MODE_STRICT 0
+#endif
+
+#ifndef SECCOMP_SET_MODE_FILTER
+#define SECCOMP_SET_MODE_FILTER 1
+#endif
+
+#ifndef SECCOMP_GET_ACTION_AVAIL
+#define SECCOMP_GET_ACTION_AVAIL 2
+#endif
+
+#ifndef SECCOMP_FILTER_FLAG_TSYNC
+#define SECCOMP_FILTER_FLAG_TSYNC 1
+#endif
+
+#ifndef SECCOMP_FILTER_FLAG_LOG
+#define SECCOMP_FILTER_FLAG_LOG 2
+#endif
+
+#ifndef seccomp
+int seccomp(unsigned int op, unsigned int flags, void *args)
+{
+ errno = 0;
+ return syscall(__NR_seccomp, op, flags, args);
+}
+#endif
+
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
#elif __BYTE_ORDER == __BIG_ENDIAN
}
}
-/* Tests kernel support by checking for a copy_from_user() fault on * NULL. */
+/* Tests kernel support by checking for a copy_from_user() fault on NULL. */
TEST(mode_filter_support)
{
long ret;
EXPECT_EQ(EINVAL, errno);
}
+TEST(log_all)
+{
+ struct sock_filter filter[] = {
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
+ };
+ struct sock_fprog prog = {
+ .len = (unsigned short)ARRAY_SIZE(filter),
+ .filter = filter,
+ };
+ long ret;
+ pid_t parent = getppid();
+
+ ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
+ ASSERT_EQ(0, ret);
+
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
+ ASSERT_EQ(0, ret);
+
+ /* getppid() should succeed and be logged (no check for logging) */
+ EXPECT_EQ(parent, syscall(__NR_getppid));
+}
+
TEST_SIGNAL(unknown_ret_is_kill_inside, SIGSYS)
{
struct sock_filter filter[] = {
close(fd);
}
+/* This is a thread task to die via seccomp filter violation. */
+void *kill_thread(void *data)
+{
+ bool die = (bool)data;
+
+ if (die) {
+ prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
+ return (void *)SIBLING_EXIT_FAILURE;
+ }
+
+ return (void *)SIBLING_EXIT_UNKILLED;
+}
+
+/* Prepare a thread that will kill itself or both of us. */
+void kill_thread_or_group(struct __test_metadata *_metadata, bool kill_process)
+{
+ pthread_t thread;
+ void *status;
+ /* Kill only when calling __NR_prctl. */
+ struct sock_filter filter_thread[] = {
+ BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
+ offsetof(struct seccomp_data, nr)),
+ BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_THREAD),
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
+ };
+ struct sock_fprog prog_thread = {
+ .len = (unsigned short)ARRAY_SIZE(filter_thread),
+ .filter = filter_thread,
+ };
+ struct sock_filter filter_process[] = {
+ BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
+ offsetof(struct seccomp_data, nr)),
+ BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_PROCESS),
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
+ };
+ struct sock_fprog prog_process = {
+ .len = (unsigned short)ARRAY_SIZE(filter_process),
+ .filter = filter_process,
+ };
+
+ ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
+ TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
+ }
+
+ ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0,
+ kill_process ? &prog_process : &prog_thread));
+
+ /*
+ * Add the KILL_THREAD rule again to make sure that the KILL_PROCESS
+ * flag cannot be downgraded by a new filter.
+ */
+ ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog_thread));
+
+ /* Start a thread that will exit immediately. */
+ ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)false));
+ ASSERT_EQ(0, pthread_join(thread, &status));
+ ASSERT_EQ(SIBLING_EXIT_UNKILLED, (unsigned long)status);
+
+ /* Start a thread that will die immediately. */
+ ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)true));
+ ASSERT_EQ(0, pthread_join(thread, &status));
+ ASSERT_NE(SIBLING_EXIT_FAILURE, (unsigned long)status);
+
+ /*
+ * If we get here, only the spawned thread died. Let the parent know
+ * the whole process didn't die (i.e. this thread, the spawner,
+ * stayed running).
+ */
+ exit(42);
+}
+
+TEST(KILL_thread)
+{
+ int status;
+ pid_t child_pid;
+
+ child_pid = fork();
+ ASSERT_LE(0, child_pid);
+ if (child_pid == 0) {
+ kill_thread_or_group(_metadata, false);
+ _exit(38);
+ }
+
+ ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
+
+ /* If only the thread was killed, we'll see exit 42. */
+ ASSERT_TRUE(WIFEXITED(status));
+ ASSERT_EQ(42, WEXITSTATUS(status));
+}
+
+TEST(KILL_process)
+{
+ int status;
+ pid_t child_pid;
+
+ child_pid = fork();
+ ASSERT_LE(0, child_pid);
+ if (child_pid == 0) {
+ kill_thread_or_group(_metadata, true);
+ _exit(38);
+ }
+
+ ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
+
+ /* If the entire process was killed, we'll see SIGSYS. */
+ ASSERT_TRUE(WIFSIGNALED(status));
+ ASSERT_EQ(SIGSYS, WTERMSIG(status));
+}
+
/* TODO(wad) add 64-bit versus 32-bit arg tests. */
TEST(arg_out_of_range)
{
EXPECT_EQ(EINVAL, errno);
}
+#define ERRNO_FILTER(name, errno) \
+ struct sock_filter _read_filter_##name[] = { \
+ BPF_STMT(BPF_LD|BPF_W|BPF_ABS, \
+ offsetof(struct seccomp_data, nr)), \
+ BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), \
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | errno), \
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), \
+ }; \
+ struct sock_fprog prog_##name = { \
+ .len = (unsigned short)ARRAY_SIZE(_read_filter_##name), \
+ .filter = _read_filter_##name, \
+ }
+
+/* Make sure basic errno values are correctly passed through a filter. */
TEST(ERRNO_valid)
{
- struct sock_filter filter[] = {
- BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
- offsetof(struct seccomp_data, nr)),
- BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
- BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | E2BIG),
- BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
- };
- struct sock_fprog prog = {
- .len = (unsigned short)ARRAY_SIZE(filter),
- .filter = filter,
- };
+ ERRNO_FILTER(valid, E2BIG);
long ret;
pid_t parent = getppid();
ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
ASSERT_EQ(0, ret);
- ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_valid);
ASSERT_EQ(0, ret);
EXPECT_EQ(parent, syscall(__NR_getppid));
EXPECT_EQ(E2BIG, errno);
}
+/* Make sure an errno of zero is correctly handled by the arch code. */
TEST(ERRNO_zero)
{
- struct sock_filter filter[] = {
- BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
- offsetof(struct seccomp_data, nr)),
- BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
- BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | 0),
- BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
- };
- struct sock_fprog prog = {
- .len = (unsigned short)ARRAY_SIZE(filter),
- .filter = filter,
- };
+ ERRNO_FILTER(zero, 0);
long ret;
pid_t parent = getppid();
ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
ASSERT_EQ(0, ret);
- ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_zero);
ASSERT_EQ(0, ret);
EXPECT_EQ(parent, syscall(__NR_getppid));
EXPECT_EQ(0, read(0, NULL, 0));
}
+/*
+ * The SECCOMP_RET_DATA mask is 16 bits wide, but errno is smaller.
+ * This tests that the errno value gets capped correctly, fixed by
+ * 580c57f10768 ("seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO").
+ */
TEST(ERRNO_capped)
{
- struct sock_filter filter[] = {
- BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
- offsetof(struct seccomp_data, nr)),
- BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
- BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | 4096),
- BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
- };
- struct sock_fprog prog = {
- .len = (unsigned short)ARRAY_SIZE(filter),
- .filter = filter,
- };
+ ERRNO_FILTER(capped, 4096);
long ret;
pid_t parent = getppid();
ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
ASSERT_EQ(0, ret);
- ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_capped);
ASSERT_EQ(0, ret);
EXPECT_EQ(parent, syscall(__NR_getppid));
EXPECT_EQ(4095, errno);
}
+/*
+ * Filters are processed in reverse order: last applied is executed first.
+ * Since only the SECCOMP_RET_ACTION mask is tested for return values, the
+ * SECCOMP_RET_DATA mask results will follow the most recently applied
+ * matching filter return (and not the lowest or highest value).
+ */
+TEST(ERRNO_order)
+{
+ ERRNO_FILTER(first, 11);
+ ERRNO_FILTER(second, 13);
+ ERRNO_FILTER(third, 12);
+ long ret;
+ pid_t parent = getppid();
+
+ ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
+ ASSERT_EQ(0, ret);
+
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_first);
+ ASSERT_EQ(0, ret);
+
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_second);
+ ASSERT_EQ(0, ret);
+
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_third);
+ ASSERT_EQ(0, ret);
+
+ EXPECT_EQ(parent, syscall(__NR_getppid));
+ EXPECT_EQ(-1, read(0, NULL, 0));
+ EXPECT_EQ(12, errno);
+}
+
FIXTURE_DATA(TRAP) {
struct sock_fprog prog;
};
FIXTURE_DATA(precedence) {
struct sock_fprog allow;
+ struct sock_fprog log;
struct sock_fprog trace;
struct sock_fprog error;
struct sock_fprog trap;
struct sock_filter allow_insns[] = {
BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
};
+ struct sock_filter log_insns[] = {
+ BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
+ offsetof(struct seccomp_data, nr)),
+ BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
+ };
struct sock_filter trace_insns[] = {
BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
offsetof(struct seccomp_data, nr)),
memcpy(self->_x.filter, &_x##_insns, sizeof(_x##_insns)); \
self->_x.len = (unsigned short)ARRAY_SIZE(_x##_insns)
FILTER_ALLOC(allow);
+ FILTER_ALLOC(log);
FILTER_ALLOC(trace);
FILTER_ALLOC(error);
FILTER_ALLOC(trap);
{
#define FILTER_FREE(_x) if (self->_x.filter) free(self->_x.filter)
FILTER_FREE(allow);
+ FILTER_FREE(log);
FILTER_FREE(trace);
FILTER_FREE(error);
FILTER_FREE(trap);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
ASSERT_EQ(0, ret);
/* Should work just fine. */
ASSERT_EQ(0, ret);
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
/* Should work just fine. */
EXPECT_EQ(parent, syscall(__NR_getppid));
/* No ptracer */
EXPECT_EQ(-1, syscall(__NR_getpid));
}
+TEST_F(precedence, log_is_fifth)
+{
+ pid_t mypid, parent;
+ long ret;
+
+ mypid = getpid();
+ parent = getppid();
+ ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
+ ASSERT_EQ(0, ret);
+
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
+ ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
+ /* Should work just fine. */
+ EXPECT_EQ(parent, syscall(__NR_getppid));
+ /* Should also work just fine */
+ EXPECT_EQ(mypid, syscall(__NR_getpid));
+}
+
+TEST_F(precedence, log_is_fifth_in_any_order)
+{
+ pid_t mypid, parent;
+ long ret;
+
+ mypid = getpid();
+ parent = getppid();
+ ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
+ ASSERT_EQ(0, ret);
+
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
+ ASSERT_EQ(0, ret);
+ ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
+ ASSERT_EQ(0, ret);
+ /* Should work just fine. */
+ EXPECT_EQ(parent, syscall(__NR_getppid));
+ /* Should also work just fine */
+ EXPECT_EQ(mypid, syscall(__NR_getpid));
+}
+
#ifndef PTRACE_O_TRACESECCOMP
#define PTRACE_O_TRACESECCOMP 0x00000080
#endif
# error "Do not know how to find your architecture's registers and syscalls"
#endif
+/* When the syscall return can't be changed, stub out the tests for it. */
+#ifdef SYSCALL_NUM_RET_SHARE_REG
+# define EXPECT_SYSCALL_RETURN(val, action) EXPECT_EQ(-1, action)
+#else
+# define EXPECT_SYSCALL_RETURN(val, action) EXPECT_EQ(val, action)
+#endif
+
/* Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
* architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
*/
#ifdef SYSCALL_NUM_RET_SHARE_REG
TH_LOG("Can't modify syscall return on this architecture");
#else
- regs.SYSCALL_RET = 1;
+ regs.SYSCALL_RET = EPERM;
#endif
#ifdef HAVE_GETREGS
if (nr == __NR_getpid)
change_syscall(_metadata, tracee, __NR_getppid);
+ if (nr == __NR_open)
+ change_syscall(_metadata, tracee, -1);
}
FIXTURE_DATA(TRACE_syscall) {
free(self->prog.filter);
}
+TEST_F(TRACE_syscall, ptrace_syscall_redirected)
+{
+ /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
+ teardown_trace_fixture(_metadata, self->tracer);
+ self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
+ true);
+
+ /* Tracer will redirect getpid to getppid. */
+ EXPECT_NE(self->mypid, syscall(__NR_getpid));
+}
+
+TEST_F(TRACE_syscall, ptrace_syscall_dropped)
+{
+ /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
+ teardown_trace_fixture(_metadata, self->tracer);
+ self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
+ true);
+
+ /* Tracer should skip the open syscall, resulting in EPERM. */
+ EXPECT_SYSCALL_RETURN(EPERM, syscall(__NR_open));
+}
+
TEST_F(TRACE_syscall, syscall_allowed)
{
long ret;
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
ASSERT_EQ(0, ret);
-#ifdef SYSCALL_NUM_RET_SHARE_REG
- /* gettid has been skipped */
- EXPECT_EQ(-1, syscall(__NR_gettid));
-#else
/* gettid has been skipped and an altered return value stored. */
- EXPECT_EQ(1, syscall(__NR_gettid));
-#endif
+ EXPECT_SYSCALL_RETURN(EPERM, syscall(__NR_gettid));
EXPECT_NE(self->mytid, syscall(__NR_gettid));
}
ASSERT_EQ(0, ret);
/* Tracer will redirect getpid to getppid, and we should see EPERM. */
+ errno = 0;
EXPECT_EQ(-1, syscall(__NR_getpid));
EXPECT_EQ(EPERM, errno);
}
EXPECT_NE(self->mypid, syscall(__NR_getpid));
}
-#ifndef __NR_seccomp
-# if defined(__i386__)
-# define __NR_seccomp 354
-# elif defined(__x86_64__)
-# define __NR_seccomp 317
-# elif defined(__arm__)
-# define __NR_seccomp 383
-# elif defined(__aarch64__)
-# define __NR_seccomp 277
-# elif defined(__hppa__)
-# define __NR_seccomp 338
-# elif defined(__powerpc__)
-# define __NR_seccomp 358
-# elif defined(__s390__)
-# define __NR_seccomp 348
-# else
-# warning "seccomp syscall number unknown for this architecture"
-# define __NR_seccomp 0xffff
-# endif
-#endif
-
-#ifndef SECCOMP_SET_MODE_STRICT
-#define SECCOMP_SET_MODE_STRICT 0
-#endif
-
-#ifndef SECCOMP_SET_MODE_FILTER
-#define SECCOMP_SET_MODE_FILTER 1
-#endif
-
-#ifndef SECCOMP_FILTER_FLAG_TSYNC
-#define SECCOMP_FILTER_FLAG_TSYNC 1
-#endif
-
-#ifndef seccomp
-int seccomp(unsigned int op, unsigned int flags, void *args)
-{
- errno = 0;
- return syscall(__NR_seccomp, op, flags, args);
-}
-#endif
-
TEST(seccomp_syscall)
{
struct sock_filter filter[] = {
}
}
+/*
+ * Test detection of known and unknown filter flags. Userspace needs to be able
+ * to check if a filter flag is supported by the current kernel and a good way
+ * of doing that is by attempting to enter filter mode, with the flag bit in
+ * question set, and a NULL pointer for the _args_ parameter. EFAULT indicates
+ * that the flag is valid and EINVAL indicates that the flag is invalid.
+ */
+TEST(detect_seccomp_filter_flags)
+{
+ unsigned int flags[] = { SECCOMP_FILTER_FLAG_TSYNC,
+ SECCOMP_FILTER_FLAG_LOG };
+ unsigned int flag, all_flags;
+ int i;
+ long ret;
+
+ /* Test detection of known-good filter flags */
+ for (i = 0, all_flags = 0; i < ARRAY_SIZE(flags); i++) {
+ flag = flags[i];
+ ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
+ ASSERT_NE(ENOSYS, errno) {
+ TH_LOG("Kernel does not support seccomp syscall!");
+ }
+ EXPECT_EQ(-1, ret);
+ EXPECT_EQ(EFAULT, errno) {
+ TH_LOG("Failed to detect that a known-good filter flag (0x%X) is supported!",
+ flag);
+ }
+
+ all_flags |= flag;
+ }
+
+ /* Test detection of all known-good filter flags */
+ ret = seccomp(SECCOMP_SET_MODE_FILTER, all_flags, NULL);
+ EXPECT_EQ(-1, ret);
+ EXPECT_EQ(EFAULT, errno) {
+ TH_LOG("Failed to detect that all known-good filter flags (0x%X) are supported!",
+ all_flags);
+ }
+
+ /* Test detection of an unknown filter flag */
+ flag = -1;
+ ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
+ EXPECT_EQ(-1, ret);
+ EXPECT_EQ(EINVAL, errno) {
+ TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported!",
+ flag);
+ }
+
+ /*
+ * Test detection of an unknown filter flag that may simply need to be
+ * added to this test
+ */
+ flag = flags[ARRAY_SIZE(flags) - 1] << 1;
+ ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
+ EXPECT_EQ(-1, ret);
+ EXPECT_EQ(EINVAL, errno) {
+ TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported! Does a new flag need to be added to this test?",
+ flag);
+ }
+}
+
TEST(TSYNC_first)
{
struct sock_filter filter[] = {
_metadata->passed = 0;
}
+TEST_SIGNAL(filter_flag_log, SIGSYS)
+{
+ struct sock_filter allow_filter[] = {
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
+ };
+ struct sock_filter kill_filter[] = {
+ BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
+ offsetof(struct seccomp_data, nr)),
+ BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
+ };
+ struct sock_fprog allow_prog = {
+ .len = (unsigned short)ARRAY_SIZE(allow_filter),
+ .filter = allow_filter,
+ };
+ struct sock_fprog kill_prog = {
+ .len = (unsigned short)ARRAY_SIZE(kill_filter),
+ .filter = kill_filter,
+ };
+ long ret;
+ pid_t parent = getppid();
+
+ ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
+ ASSERT_EQ(0, ret);
+
+ /* Verify that the FILTER_FLAG_LOG flag isn't accepted in strict mode */
+ ret = seccomp(SECCOMP_SET_MODE_STRICT, SECCOMP_FILTER_FLAG_LOG,
+ &allow_prog);
+ ASSERT_NE(ENOSYS, errno) {
+ TH_LOG("Kernel does not support seccomp syscall!");
+ }
+ EXPECT_NE(0, ret) {
+ TH_LOG("Kernel accepted FILTER_FLAG_LOG flag in strict mode!");
+ }
+ EXPECT_EQ(EINVAL, errno) {
+ TH_LOG("Kernel returned unexpected errno for FILTER_FLAG_LOG flag in strict mode!");
+ }
+
+ /* Verify that a simple, permissive filter can be added with no flags */
+ ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
+ EXPECT_EQ(0, ret);
+
+ /* See if the same filter can be added with the FILTER_FLAG_LOG flag */
+ ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
+ &allow_prog);
+ ASSERT_NE(EINVAL, errno) {
+ TH_LOG("Kernel does not support the FILTER_FLAG_LOG flag!");
+ }
+ EXPECT_EQ(0, ret);
+
+ /* Ensure that the kill filter works with the FILTER_FLAG_LOG flag */
+ ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
+ &kill_prog);
+ EXPECT_EQ(0, ret);
+
+ EXPECT_EQ(parent, syscall(__NR_getppid));
+ /* getpid() should never return. */
+ EXPECT_EQ(0, syscall(__NR_getpid));
+}
+
+TEST(get_action_avail)
+{
+ __u32 actions[] = { SECCOMP_RET_KILL_THREAD, SECCOMP_RET_TRAP,
+ SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE,
+ SECCOMP_RET_LOG, SECCOMP_RET_ALLOW };
+ __u32 unknown_action = 0x10000000U;
+ int i;
+ long ret;
+
+ ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[0]);
+ ASSERT_NE(ENOSYS, errno) {
+ TH_LOG("Kernel does not support seccomp syscall!");
+ }
+ ASSERT_NE(EINVAL, errno) {
+ TH_LOG("Kernel does not support SECCOMP_GET_ACTION_AVAIL operation!");
+ }
+ EXPECT_EQ(ret, 0);
+
+ for (i = 0; i < ARRAY_SIZE(actions); i++) {
+ ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[i]);
+ EXPECT_EQ(ret, 0) {
+ TH_LOG("Expected action (0x%X) not available!",
+ actions[i]);
+ }
+ }
+
+ /* Check that an unknown action is handled properly (EOPNOTSUPP) */
+ ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &unknown_action);
+ EXPECT_EQ(ret, -1);
+ EXPECT_EQ(errno, EOPNOTSUPP);
+}
+
/*
* TODO:
* - add microbenchmarks
* - endianness checking when appropriate
* - 64-bit arg prodding
* - arch value testing (x86 modes especially)
+ * - verify that FILTER_FLAG_LOG filters generate log messages
+ * - verify that RET_LOG generates log messages
* - ...
*/
projects / linux-2.6-microblaze.git / blobdiff