int main(int argc, char ** argv)
{
pid_t pid;
int mode, status;
int sk_pair[2], sk, ret;
char c = 'K';
test_init(argc, argv);
if (socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair)) {
pr_perror("socketpair");
return -1;
}
pid = fork();
if (pid < 0) {
pr_perror("fork");
return -1;
}
if (pid == 0) {
pthread_t th;
void *p = NULL;
if (pthread_mutex_init(&getpid_wait, NULL)) {
pr_perror("pthread_mutex_init");
_exit(1);
}
sk = sk_pair[1];
close(sk_pair[0]);
if (filter_syscall(__NR_getpid, 0) < 0)
_exit(1);
zdtm_seccomp = 1;
pthread_mutex_lock(&getpid_wait);
pthread_create(&th, NULL, wait_and_getpid, NULL);
test_msg("SECCOMP_MODE_FILTER is enabled\n");
if (write(sk, &c, 1) != 1) {
pr_perror("write");
_exit(1);
}
if (read(sk, &c, 1) != 1) {
pr_perror("read");
_exit(1);
}
/* Now we have c/r'd with a shared filter, so let's install
* another filter with TSYNC and make sure that it is
* inherited.
*/
if (filter_syscall(__NR_ptrace, SECCOMP_FILTER_FLAG_TSYNC) < 0)
_exit(1);
pthread_mutex_unlock(&getpid_wait);
if (pthread_join(th, &p) != 0) {
pr_perror("pthread_join");
exit(1);
}
/* Here we're abusing pthread exit slightly: if the thread gets
* to call pthread_exit, the value of p is one, but if it gets
* killed pthread_join doesn't set a value since the thread
* didn't, so the value is null; we exit 0 to indicate success
* as usual.
*/
syscall(__NR_exit, p);
}
sk = sk_pair[0];
close(sk_pair[1]);
if ((ret = read(sk, &c, 1)) != 1) {
pr_perror("read %d", ret);
goto err;
}
test_daemon();
test_waitsig();
mode = get_seccomp_mode(pid);
if (write(sk, &c, 1) != 1) {
pr_perror("write");
goto err;
}
if (waitpid(pid, &status, 0) != pid) {
pr_perror("waitpid");
exit(1);
}
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
pr_perror("expected 0 exit, got %d\n", WEXITSTATUS(status));
exit(1);
}
if (mode != SECCOMP_MODE_FILTER) {
fail("seccomp mode mismatch %d\n", mode);
return 1;
}
pass();
return 0;
err:
kill(pid, SIGKILL);
return 1;
}
int filter_syscall(int syscall_nr)
{
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, syscall_nr, 0, 1),
BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL),
BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW),
};
struct sock_fprog bpf_prog = {
.len = (unsigned short)(sizeof(filter)/sizeof(filter[0])),
.filter = filter,
};
if (prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &bpf_prog) < 0) {
pr_perror("prctl failed");
return -1;
}
return 0;
}
int main(int argc, char ** argv)
{
pid_t pid;
int mode, status;
int sk_pair[2], sk, ret;
char c = 'K';
test_init(argc, argv);
if (socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair)) {
pr_perror("socketpair");
return -1;
}
pid = fork();
if (pid < 0) {
pr_perror("fork");
return -1;
}
if (pid == 0) {
pid_t pid2;
sk = sk_pair[1];
close(sk_pair[0]);
if (filter_syscall(__NR_ptrace) < 0)
_exit(1);
if (filter_syscall(__NR_fstat) < 0)
_exit(1);
zdtm_seccomp = 1;
test_msg("SECCOMP_MODE_FILTER is enabled\n");
pid2 = fork();
if (pid2 < 0)
_exit(1);
if (!pid2) {
if (write(sk, &c, 1) != 1) {
pr_perror("write");
_exit(1);
}
if (read(sk, &c, 1) != 1) {
pr_perror("read");
_exit(1);
}
/* We expect to be killed by our policy above. */
ptrace(PTRACE_TRACEME);
_exit(1);
}
if (waitpid(pid2, &status, 0) != pid2) {
pr_perror("waitpid");
_exit(1);
}
if (WTERMSIG(status) != SIGSYS) {
pr_perror("expected SIGSYS, got %d\n", WTERMSIG(status));
_exit(1);
}
_exit(0);
}
sk = sk_pair[0];
close(sk_pair[1]);
if ((ret = read(sk, &c, 1)) != 1) {
pr_perror("read %d", ret);
goto err;
}
test_daemon();
test_waitsig();
mode = get_seccomp_mode(pid);
if (write(sk, &c, 1) != 1) {
pr_perror("write");
goto err;
}
if (mode != SECCOMP_MODE_FILTER) {
fail("seccomp mode mismatch %d\n", mode);
return 1;
}
if (waitpid(pid, &status, 0) != pid) {
pr_perror("waitpid");
_exit(1);
}
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
fail("bad exit status");
return 1;
}
pass();
return 0;
err:
kill(pid, SIGKILL);
return 1;
}
