// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
 *
 * Test code for seccomp bpf.
 */

#define _GNU_SOURCE
#include <sys/types.h>

/*
 * glibc 2.26 and later have SIGSYS in siginfo_t. Before that,
 * we need to use the kernel's siginfo.h file and trick glibc
 * into accepting it.
 */
#if !__GLIBC_PREREQ(2, 26)
# include <asm/siginfo.h>
# define __have_siginfo_t 1
# define __have_sigval_t 1
# define __have_sigevent_t 1
#endif

#include <errno.h>
#include <linux/filter.h>
#include <sys/prctl.h>
#include <sys/ptrace.h>
#include <sys/time.h>
#include <sys/user.h>
#include <linux/prctl.h>
#include <linux/ptrace.h>
#include <linux/seccomp.h>
#include <pthread.h>
#include <semaphore.h>
#include <signal.h>
#include <stddef.h>
#include <stdbool.h>
#include <string.h>
#include <time.h>
#include <limits.h>
#include <linux/elf.h>
#include <sys/uio.h>
#include <sys/utsname.h>
#include <sys/fcntl.h>
#include <sys/mman.h>
#include <sys/times.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <linux/kcmp.h>
#include <sys/resource.h>
#include <sys/capability.h>
#include <linux/perf_event.h>

#include <unistd.h>
#include <sys/syscall.h>
#include <poll.h>

#include "kselftest_harness.h"
#include "../clone3/clone3_selftests.h"

/* Attempt to de-conflict with the selftests tree. */
#ifndef SKIP
#define SKIP(s, ...)    XFAIL(s, ##__VA_ARGS__)
#endif

#ifndef MIN
#define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
#endif

#ifndef PR_SET_PTRACER
# define PR_SET_PTRACER 0x59616d61
#endif

#ifndef noinline
#define noinline __attribute__((noinline))
#endif

#ifndef __nocf_check
#define __nocf_check __attribute__((nocf_check))
#endif

#ifndef __naked
#define __naked __attribute__((__naked__))
#endif

#ifndef PR_SET_NO_NEW_PRIVS
#define PR_SET_NO_NEW_PRIVS 38
#define PR_GET_NO_NEW_PRIVS 39
#endif

#ifndef PR_SECCOMP_EXT
#define PR_SECCOMP_EXT 43
#endif

#ifndef SECCOMP_EXT_ACT
#define SECCOMP_EXT_ACT 1
#endif

#ifndef SECCOMP_EXT_ACT_TSYNC
#define SECCOMP_EXT_ACT_TSYNC 1
#endif

#ifndef SECCOMP_MODE_STRICT
#define SECCOMP_MODE_STRICT 1
#endif

#ifndef SECCOMP_MODE_FILTER
#define SECCOMP_MODE_FILTER 2
#endif

#ifndef SECCOMP_RET_ALLOW
struct seccomp_data {
        int nr;
        __u32 arch;
        __u64 instruction_pointer;
        __u64 args[6];
};
#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(__riscv)
#  define __NR_seccomp 277
# elif defined(__csky__)
#  define __NR_seccomp 277
# elif defined(__loongarch__)
#  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
# elif defined(__xtensa__)
#  define __NR_seccomp 337
# elif defined(__sh__)
#  define __NR_seccomp 372
# elif defined(__mc68000__)
#  define __NR_seccomp 380
# else
#  warning "seccomp syscall number unknown for this architecture"
#  define __NR_seccomp 0xffff
# endif
#endif

#ifndef __NR_uretprobe
# if defined(__x86_64__)
#  define __NR_uretprobe 335
# 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_GET_NOTIF_SIZES
#define SECCOMP_GET_NOTIF_SIZES 3
#endif

#ifndef SECCOMP_FILTER_FLAG_TSYNC
#define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0)
#endif

#ifndef SECCOMP_FILTER_FLAG_LOG
#define SECCOMP_FILTER_FLAG_LOG (1UL << 1)
#endif

#ifndef SECCOMP_FILTER_FLAG_SPEC_ALLOW
#define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2)
#endif

#ifndef PTRACE_SECCOMP_GET_METADATA
#define PTRACE_SECCOMP_GET_METADATA     0x420d

struct seccomp_metadata {
        __u64 filter_off;       /* Input: which filter */
        __u64 flags;             /* Output: filter's flags */
};
#endif

#ifndef SECCOMP_FILTER_FLAG_NEW_LISTENER
#define SECCOMP_FILTER_FLAG_NEW_LISTENER        (1UL << 3)
#endif

#ifndef SECCOMP_RET_USER_NOTIF
#define SECCOMP_RET_USER_NOTIF 0x7fc00000U

#define SECCOMP_IOC_MAGIC               '!'
#define SECCOMP_IO(nr)                  _IO(SECCOMP_IOC_MAGIC, nr)
#define SECCOMP_IOR(nr, type)           _IOR(SECCOMP_IOC_MAGIC, nr, type)
#define SECCOMP_IOW(nr, type)           _IOW(SECCOMP_IOC_MAGIC, nr, type)
#define SECCOMP_IOWR(nr, type)          _IOWR(SECCOMP_IOC_MAGIC, nr, type)

/* Flags for seccomp notification fd ioctl. */
#define SECCOMP_IOCTL_NOTIF_RECV        SECCOMP_IOWR(0, struct seccomp_notif)
#define SECCOMP_IOCTL_NOTIF_SEND        SECCOMP_IOWR(1, \
                                                struct seccomp_notif_resp)
#define SECCOMP_IOCTL_NOTIF_ID_VALID    SECCOMP_IOW(2, __u64)

struct seccomp_notif {
        __u64 id;
        __u32 pid;
        __u32 flags;
        struct seccomp_data data;
};

struct seccomp_notif_resp {
        __u64 id;
        __s64 val;
        __s32 error;
        __u32 flags;
};

struct seccomp_notif_sizes {
        __u16 seccomp_notif;
        __u16 seccomp_notif_resp;
        __u16 seccomp_data;
};
#endif

#ifndef SECCOMP_IOCTL_NOTIF_ADDFD
/* On success, the return value is the remote process's added fd number */
#define SECCOMP_IOCTL_NOTIF_ADDFD       SECCOMP_IOW(3,  \
                                                struct seccomp_notif_addfd)

/* valid flags for seccomp_notif_addfd */
#define SECCOMP_ADDFD_FLAG_SETFD        (1UL << 0) /* Specify remote fd */

struct seccomp_notif_addfd {
        __u64 id;
        __u32 flags;
        __u32 srcfd;
        __u32 newfd;
        __u32 newfd_flags;
};
#endif

#ifndef SECCOMP_ADDFD_FLAG_SEND
#define SECCOMP_ADDFD_FLAG_SEND (1UL << 1) /* Addfd and return it, atomically */
#endif

struct seccomp_notif_addfd_small {
        __u64 id;
        char weird[4];
};
#define SECCOMP_IOCTL_NOTIF_ADDFD_SMALL \
        SECCOMP_IOW(3, struct seccomp_notif_addfd_small)

struct seccomp_notif_addfd_big {
        union {
                struct seccomp_notif_addfd addfd;
                char buf[sizeof(struct seccomp_notif_addfd) + 8];
        };
};
#define SECCOMP_IOCTL_NOTIF_ADDFD_BIG   \
        SECCOMP_IOWR(3, struct seccomp_notif_addfd_big)

#ifndef PTRACE_EVENTMSG_SYSCALL_ENTRY
#define PTRACE_EVENTMSG_SYSCALL_ENTRY   1
#define PTRACE_EVENTMSG_SYSCALL_EXIT    2
#endif

#ifndef SECCOMP_USER_NOTIF_FLAG_CONTINUE
#define SECCOMP_USER_NOTIF_FLAG_CONTINUE 0x00000001
#endif

#ifndef SECCOMP_FILTER_FLAG_TSYNC_ESRCH
#define SECCOMP_FILTER_FLAG_TSYNC_ESRCH (1UL << 4)
#endif

#ifndef SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV
#define SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV (1UL << 5)
#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__ == __ORDER_LITTLE_ENDIAN__
#define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
#define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]) + sizeof(__u32))
#else
#error "wut? Unknown __BYTE_ORDER__?!"
#endif

#define SIBLING_EXIT_UNKILLED   0xbadbeef
#define SIBLING_EXIT_FAILURE    0xbadface
#define SIBLING_EXIT_NEWPRIVS   0xbadfeed

static int __filecmp(pid_t pid1, pid_t pid2, int fd1, int fd2)
{
#ifdef __NR_kcmp
        errno = 0;
        return syscall(__NR_kcmp, pid1, pid2, KCMP_FILE, fd1, fd2);
#else
        errno = ENOSYS;
        return -1;
#endif
}

/* Have TH_LOG report actual location filecmp() is used. */
#define filecmp(pid1, pid2, fd1, fd2)   ({              \
        int _ret;                                       \
                                                        \
        _ret = __filecmp(pid1, pid2, fd1, fd2);         \
        if (_ret != 0) {                                \
                if (_ret < 0 && errno == ENOSYS) {      \
                        TH_LOG("kcmp() syscall missing (test is less accurate)");\
                        _ret = 0;                       \
                }                                       \
        }                                               \
        _ret; })

TEST(kcmp)
{
        int ret;

        ret = __filecmp(getpid(), getpid(), 1, 1);
        EXPECT_EQ(ret, 0);
        if (ret != 0 && errno == ENOSYS)
                SKIP(return, "Kernel does not support kcmp() (missing CONFIG_KCMP?)");
}

TEST(mode_strict_support)
{
        long ret;

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support CONFIG_SECCOMP");
        }
        syscall(__NR_exit, 0);
}

TEST_SIGNAL(mode_strict_cannot_call_prctl, SIGKILL)
{
        long ret;

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support CONFIG_SECCOMP");
        }
        syscall(__NR_prctl, PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
                NULL, NULL, NULL);
        EXPECT_FALSE(true) {
                TH_LOG("Unreachable!");
        }
}

/* Note! This doesn't test no new privs behavior */
TEST(no_new_privs_support)
{
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        EXPECT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }
}

/* Tests kernel support by checking for a copy_from_user() fault on NULL. */
TEST(mode_filter_support)
{
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, NULL, NULL);
        EXPECT_EQ(-1, ret);
        EXPECT_EQ(EFAULT, errno) {
                TH_LOG("Kernel does not support CONFIG_SECCOMP_FILTER!");
        }
}

TEST(mode_filter_without_nnp)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;
        cap_t cap = cap_get_proc();
        cap_flag_value_t is_cap_sys_admin = 0;

        ret = prctl(PR_GET_NO_NEW_PRIVS, 0, NULL, 0, 0);
        ASSERT_LE(0, ret) {
                TH_LOG("Expected 0 or unsupported for NO_NEW_PRIVS");
        }
        errno = 0;
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        /* Succeeds with CAP_SYS_ADMIN, fails without */
        cap_get_flag(cap, CAP_SYS_ADMIN, CAP_EFFECTIVE, &is_cap_sys_admin);
        if (!is_cap_sys_admin) {
                EXPECT_EQ(-1, ret);
                EXPECT_EQ(EACCES, errno);
        } else {
                EXPECT_EQ(0, ret);
        }
}

#define MAX_INSNS_PER_PATH 32768

TEST(filter_size_limits)
{
        int i;
        int count = BPF_MAXINSNS + 1;
        struct sock_filter allow[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_filter *filter;
        struct sock_fprog prog = { };
        long ret;

        filter = calloc(count, sizeof(*filter));
        ASSERT_NE(NULL, filter);

        for (i = 0; i < count; i++)
                filter[i] = allow[0];

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        prog.filter = filter;
        prog.len = count;

        /* Too many filter instructions in a single filter. */
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        ASSERT_NE(0, ret) {
                TH_LOG("Installing %d insn filter was allowed", prog.len);
        }

        /* One less is okay, though. */
        prog.len -= 1;
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Installing %d insn filter wasn't allowed", prog.len);
        }
}

TEST(filter_chain_limits)
{
        int i;
        int count = BPF_MAXINSNS;
        struct sock_filter allow[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_filter *filter;
        struct sock_fprog prog = { };
        long ret;

        filter = calloc(count, sizeof(*filter));
        ASSERT_NE(NULL, filter);

        for (i = 0; i < count; i++)
                filter[i] = allow[0];

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        prog.filter = filter;
        prog.len = 1;

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        ASSERT_EQ(0, ret);

        prog.len = count;

        /* Too many total filter instructions. */
        for (i = 0; i < MAX_INSNS_PER_PATH; i++) {
                ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
                if (ret != 0)
                        break;
        }
        ASSERT_NE(0, ret) {
                TH_LOG("Allowed %d %d-insn filters (total with penalties:%d)",
                       i, count, i * (count + 4));
        }
}

TEST(mode_filter_cannot_move_to_strict)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        ASSERT_EQ(0, ret);

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, 0, 0);
        EXPECT_EQ(-1, ret);
        EXPECT_EQ(EINVAL, errno);
}


TEST(mode_filter_get_seccomp)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
        EXPECT_EQ(0, ret);

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        ASSERT_EQ(0, ret);

        ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
        EXPECT_EQ(2, ret);
}


TEST(ALLOW_all)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        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);
}

TEST(empty_prog)
{
        struct sock_filter filter[] = {
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
        EXPECT_EQ(-1, 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[] = {
                BPF_STMT(BPF_RET|BPF_K, 0x10000000U),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        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);
        EXPECT_EQ(0, syscall(__NR_getpid)) {
                TH_LOG("getpid() shouldn't ever return");
        }
}

/* return code >= 0x80000000 is unused. */
TEST_SIGNAL(unknown_ret_is_kill_above_allow, SIGSYS)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, 0x90000000U),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        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);
        EXPECT_EQ(0, syscall(__NR_getpid)) {
                TH_LOG("getpid() shouldn't ever return");
        }
}

TEST_SIGNAL(KILL_all, SIGSYS)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        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);
}

TEST_SIGNAL(KILL_one, SIGSYS)
{
        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_getpid, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        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);

        EXPECT_EQ(parent, syscall(__NR_getppid));
        /* getpid() should never return. */
        EXPECT_EQ(0, syscall(__NR_getpid));
}

TEST_SIGNAL(KILL_one_arg_one, SIGSYS)
{
        void *fatal_address;
        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_times, 1, 0),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
                /* Only both with lower 32-bit for now. */
                BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(0)),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K,
                        (unsigned long)&fatal_address, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;
        pid_t parent = getppid();
        struct tms timebuf;
        clock_t clock = times(&timebuf);

        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);

        EXPECT_EQ(parent, syscall(__NR_getppid));
        EXPECT_LE(clock, syscall(__NR_times, &timebuf));
        /* times() should never return. */
        EXPECT_EQ(0, syscall(__NR_times, &fatal_address));
}

TEST_SIGNAL(KILL_one_arg_six, SIGSYS)
{
#ifndef __NR_mmap2
        int sysno = __NR_mmap;
#else
        int sysno = __NR_mmap2;
#endif
        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, sysno, 1, 0),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
                /* Only both with lower 32-bit for now. */
                BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(5)),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x0C0FFEE, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;
        pid_t parent = getppid();
        int fd;
        void *map1, *map2;
        int page_size = sysconf(_SC_PAGESIZE);

        ASSERT_LT(0, page_size);

        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);

        fd = open("/dev/zero", O_RDONLY);
        ASSERT_NE(-1, fd);

        EXPECT_EQ(parent, syscall(__NR_getppid));
        map1 = (void *)syscall(sysno,
                NULL, page_size, PROT_READ, MAP_PRIVATE, fd, page_size);
        EXPECT_NE(MAP_FAILED, map1);
        /* mmap2() should never return. */
        map2 = (void *)syscall(sysno,
                 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, 0x0C0FFEE);
        EXPECT_EQ(MAP_FAILED, map2);

        /* The test failed, so clean up the resources. */
        munmap(map1, page_size);
        munmap(map2, page_size);
        close(fd);
}

/* This is a thread task to die via seccomp filter violation. */
void *kill_thread(void *data)
{
        bool die = (bool)data;

        if (die) {
                syscall(__NR_getpid);
                return (void *)SIBLING_EXIT_FAILURE;
        }

        return (void *)SIBLING_EXIT_UNKILLED;
}

enum kill_t {
        KILL_THREAD,
        KILL_PROCESS,
        RET_UNKNOWN
};

/* Prepare a thread that will kill itself or both of us. */
void kill_thread_or_group(struct __test_metadata *_metadata,
                          enum kill_t kill_how)
{
        pthread_t thread;
        void *status;
        /* Kill only when calling __NR_getpid. */
        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_getpid, 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,
        };
        int kill = kill_how == KILL_PROCESS ? SECCOMP_RET_KILL_PROCESS : 0xAAAAAAAA;
        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_getpid, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, kill),
                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_how == KILL_THREAD ? &prog_thread
                                                     : &prog_process));

        /*
         * Add the KILL_THREAD rule again to make sure that the KILL_PROCESS
         * flag cannot be downgraded by a new filter.
         */
        if (kill_how == KILL_PROCESS)
                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, KILL_THREAD);
                _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, KILL_PROCESS);
                _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));
}

TEST(KILL_unknown)
{
        int status;
        pid_t child_pid;

        child_pid = fork();
        ASSERT_LE(0, child_pid);
        if (child_pid == 0) {
                kill_thread_or_group(_metadata, RET_UNKNOWN);
                _exit(38);
        }

        ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));

        /* If the entire process was killed, we'll see SIGSYS. */
        EXPECT_TRUE(WIFSIGNALED(status)) {
                TH_LOG("Unknown SECCOMP_RET is only killing the thread?");
        }
        ASSERT_EQ(SIGSYS, WTERMSIG(status));
}

/* TODO(wad) add 64-bit versus 32-bit arg tests. */
TEST(arg_out_of_range)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(6)),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
        EXPECT_EQ(-1, ret);
        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)
{
        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_valid);
        ASSERT_EQ(0, ret);

        EXPECT_EQ(parent, syscall(__NR_getppid));
        EXPECT_EQ(-1, read(-1, NULL, 0));
        EXPECT_EQ(E2BIG, errno);
}

/* Make sure an errno of zero is correctly handled by the arch code. */
TEST(ERRNO_zero)
{
        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_zero);
        ASSERT_EQ(0, ret);

        EXPECT_EQ(parent, syscall(__NR_getppid));
        /* "errno" of 0 is ok. */
        EXPECT_EQ(0, read(-1, 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)
{
        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_capped);
        ASSERT_EQ(0, ret);

        EXPECT_EQ(parent, syscall(__NR_getppid));
        EXPECT_EQ(-1, read(-1, NULL, 0));
        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(-1, NULL, 0));
        EXPECT_EQ(12, errno);
}

FIXTURE(TRAP) {
        struct sock_fprog prog;
};

FIXTURE_SETUP(TRAP)
{
        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_getpid, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };

        memset(&self->prog, 0, sizeof(self->prog));
        self->prog.filter = malloc(sizeof(filter));
        ASSERT_NE(NULL, self->prog.filter);
        memcpy(self->prog.filter, filter, sizeof(filter));
        self->prog.len = (unsigned short)ARRAY_SIZE(filter);
}

FIXTURE_TEARDOWN(TRAP)
{
        if (self->prog.filter)
                free(self->prog.filter);
}

TEST_F_SIGNAL(TRAP, dfl, SIGSYS)
{
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
        ASSERT_EQ(0, ret);
        syscall(__NR_getpid);
}

/* Ensure that SIGSYS overrides SIG_IGN */
TEST_F_SIGNAL(TRAP, ign, SIGSYS)
{
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        signal(SIGSYS, SIG_IGN);

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
        ASSERT_EQ(0, ret);
        syscall(__NR_getpid);
}

static siginfo_t TRAP_info;
static volatile int TRAP_nr;
static void TRAP_action(int nr, siginfo_t *info, void *void_context)
{
        memcpy(&TRAP_info, info, sizeof(TRAP_info));
        TRAP_nr = nr;
}

TEST_F(TRAP, handler)
{
        int ret, test;
        struct sigaction act;
        sigset_t mask;

        memset(&act, 0, sizeof(act));
        sigemptyset(&mask);
        sigaddset(&mask, SIGSYS);

        act.sa_sigaction = &TRAP_action;
        act.sa_flags = SA_SIGINFO;
        ret = sigaction(SIGSYS, &act, NULL);
        ASSERT_EQ(0, ret) {
                TH_LOG("sigaction failed");
        }
        ret = sigprocmask(SIG_UNBLOCK, &mask, NULL);
        ASSERT_EQ(0, ret) {
                TH_LOG("sigprocmask failed");
        }

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
        ASSERT_EQ(0, ret);
        TRAP_nr = 0;
        memset(&TRAP_info, 0, sizeof(TRAP_info));
        /* Expect the registers to be rolled back. (nr = error) may vary
         * based on arch. */
        ret = syscall(__NR_getpid);
        /* Silence gcc warning about volatile. */
        test = TRAP_nr;
        EXPECT_EQ(SIGSYS, test);
        struct local_sigsys {
                void *_call_addr;       /* calling user insn */
                int _syscall;           /* triggering system call number */
                unsigned int _arch;     /* AUDIT_ARCH_* of syscall */
        } *sigsys = (struct local_sigsys *)
#ifdef si_syscall
                &(TRAP_info.si_call_addr);
#else
                &TRAP_info.si_pid;
#endif
        EXPECT_EQ(__NR_getpid, sigsys->_syscall);
        /* Make sure arch is non-zero. */
        EXPECT_NE(0, sigsys->_arch);
        EXPECT_NE(0, (unsigned long)sigsys->_call_addr);
}

FIXTURE(precedence) {
        struct sock_fprog allow;
        struct sock_fprog log;
        struct sock_fprog trace;
        struct sock_fprog error;
        struct sock_fprog trap;
        struct sock_fprog kill;
};

FIXTURE_SETUP(precedence)
{
        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)),
                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_TRACE),
        };
        struct sock_filter error_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_ERRNO),
        };
        struct sock_filter trap_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_TRAP),
        };
        struct sock_filter kill_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_KILL),
        };

        memset(self, 0, sizeof(*self));
#define FILTER_ALLOC(_x) \
        self->_x.filter = malloc(sizeof(_x##_insns)); \
        ASSERT_NE(NULL, self->_x.filter); \
        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);
        FILTER_ALLOC(kill);
}

FIXTURE_TEARDOWN(precedence)
{
#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);
        FILTER_FREE(kill);
}

TEST_F(precedence, allow_ok)
{
        pid_t parent, res = 0;
        long ret;

        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);
        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->kill);
        ASSERT_EQ(0, ret);
        /* Should work just fine. */
        res = syscall(__NR_getppid);
        EXPECT_EQ(parent, res);
}

TEST_F_SIGNAL(precedence, kill_is_highest, SIGSYS)
{
        pid_t parent, res = 0;
        long ret;

        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);
        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->kill);
        ASSERT_EQ(0, ret);
        /* Should work just fine. */
        res = syscall(__NR_getppid);
        EXPECT_EQ(parent, res);
        /* getpid() should never return. */
        res = syscall(__NR_getpid);
        EXPECT_EQ(0, res);
}

TEST_F_SIGNAL(precedence, kill_is_highest_in_any_order, SIGSYS)
{
        pid_t parent;
        long ret;

        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->kill);
        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);
        ASSERT_EQ(0, ret);
        /* Should work just fine. */
        EXPECT_EQ(parent, syscall(__NR_getppid));
        /* getpid() should never return. */
        EXPECT_EQ(0, syscall(__NR_getpid));
}

TEST_F_SIGNAL(precedence, trap_is_second, SIGSYS)
{
        pid_t parent;
        long ret;

        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);
        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);
        /* Should work just fine. */
        EXPECT_EQ(parent, syscall(__NR_getppid));
        /* getpid() should never return. */
        EXPECT_EQ(0, syscall(__NR_getpid));
}

TEST_F_SIGNAL(precedence, trap_is_second_in_any_order, SIGSYS)
{
        pid_t parent;
        long ret;

        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->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);
        ASSERT_EQ(0, ret);
        /* Should work just fine. */
        EXPECT_EQ(parent, syscall(__NR_getppid));
        /* getpid() should never return. */
        EXPECT_EQ(0, syscall(__NR_getpid));
}

TEST_F(precedence, errno_is_third)
{
        pid_t parent;
        long ret;

        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);
        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);
        /* Should work just fine. */
        EXPECT_EQ(parent, syscall(__NR_getppid));
        EXPECT_EQ(0, syscall(__NR_getpid));
}

TEST_F(precedence, errno_is_third_in_any_order)
{
        pid_t parent;
        long ret;

        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->error);
        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->allow);
        ASSERT_EQ(0, ret);
        /* Should work just fine. */
        EXPECT_EQ(parent, syscall(__NR_getppid));
        EXPECT_EQ(0, syscall(__NR_getpid));
}

TEST_F(precedence, trace_is_fourth)
{
        pid_t parent;
        long ret;

        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);
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
        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, trace_is_fourth_in_any_order)
{
        pid_t parent;
        long ret;

        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->trace);
        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

/* Catch the Ubuntu 12.04 value error. */
#if PTRACE_EVENT_SECCOMP != 7
#undef PTRACE_EVENT_SECCOMP
#endif

#ifndef PTRACE_EVENT_SECCOMP
#define PTRACE_EVENT_SECCOMP 7
#endif

#define PTRACE_EVENT_MASK(status) ((status) >> 16)
bool tracer_running;
void tracer_stop(int sig)
{
        tracer_running = false;
}

typedef void tracer_func_t(struct __test_metadata *_metadata,
                           pid_t tracee, int status, void *args);

void start_tracer(struct __test_metadata *_metadata, int fd, pid_t tracee,
            tracer_func_t tracer_func, void *args, bool ptrace_syscall)
{
        int ret = -1;
        struct sigaction action = {
                .sa_handler = tracer_stop,
        };

        /* Allow external shutdown. */
        tracer_running = true;
        ASSERT_EQ(0, sigaction(SIGUSR1, &action, NULL));

        errno = 0;
        while (ret == -1 && errno != EINVAL)
                ret = ptrace(PTRACE_ATTACH, tracee, NULL, 0);
        ASSERT_EQ(0, ret) {
                kill(tracee, SIGKILL);
        }
        /* Wait for attach stop */
        wait(NULL);

        ret = ptrace(PTRACE_SETOPTIONS, tracee, NULL, ptrace_syscall ?
                                                      PTRACE_O_TRACESYSGOOD :
                                                      PTRACE_O_TRACESECCOMP);
        ASSERT_EQ(0, ret) {
                TH_LOG("Failed to set PTRACE_O_TRACESECCOMP");
                kill(tracee, SIGKILL);
        }
        ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
                     tracee, NULL, 0);
        ASSERT_EQ(0, ret);

        /* Unblock the tracee */
        ASSERT_EQ(1, write(fd, "A", 1));
        ASSERT_EQ(0, close(fd));

        /* Run until we're shut down. Must assert to stop execution. */
        while (tracer_running) {
                int status;

                if (wait(&status) != tracee)
                        continue;

                if (WIFSIGNALED(status)) {
                        /* Child caught a fatal signal. */
                        return;
                }
                if (WIFEXITED(status)) {
                        /* Child exited with code. */
                        return;
                }

                /* Check if we got an expected event. */
                ASSERT_EQ(WIFCONTINUED(status), false);
                ASSERT_EQ(WIFSTOPPED(status), true);
                ASSERT_EQ(WSTOPSIG(status) & SIGTRAP, SIGTRAP) {
                        TH_LOG("Unexpected WSTOPSIG: %d", WSTOPSIG(status));
                }

                tracer_func(_metadata, tracee, status, args);

                ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
                             tracee, NULL, 0);
                ASSERT_EQ(0, ret);
        }
        /* Directly report the status of our test harness results. */
        syscall(__NR_exit, _metadata->exit_code);
}

/* Common tracer setup/teardown functions. */
void cont_handler(int num)
{ }
pid_t setup_trace_fixture(struct __test_metadata *_metadata,
                          tracer_func_t func, void *args, bool ptrace_syscall)
{
        char sync;
        int pipefd[2];
        pid_t tracer_pid;
        pid_t tracee = getpid();

        /* Setup a pipe for clean synchronization. */
        ASSERT_EQ(0, pipe(pipefd));

        /* Fork a child which we'll promote to tracer */
        tracer_pid = fork();
        ASSERT_LE(0, tracer_pid);
        signal(SIGALRM, cont_handler);
        if (tracer_pid == 0) {
                close(pipefd[0]);
                start_tracer(_metadata, pipefd[1], tracee, func, args,
                             ptrace_syscall);
                syscall(__NR_exit, 0);
        }
        close(pipefd[1]);
        prctl(PR_SET_PTRACER, tracer_pid, 0, 0, 0);
        read(pipefd[0], &sync, 1);
        close(pipefd[0]);

        return tracer_pid;
}

void teardown_trace_fixture(struct __test_metadata *_metadata,
                            pid_t tracer)
{
        if (tracer) {
                int status;
                ASSERT_EQ(0, kill(tracer, SIGUSR1));
                ASSERT_EQ(tracer, waitpid(tracer, &status, 0));
        }
}

/* "poke" tracer arguments and function. */
struct tracer_args_poke_t {
        unsigned long poke_addr;
};

void tracer_poke(struct __test_metadata *_metadata, pid_t tracee, int status,
                 void *args)
{
        int ret;
        unsigned long msg;
        struct tracer_args_poke_t *info = (struct tracer_args_poke_t *)args;

        ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
        EXPECT_EQ(0, ret);
        /* If this fails, don't try to recover. */
        ASSERT_EQ(0x1001, msg) {
                kill(tracee, SIGKILL);
        }
        /*
         * Poke in the message.
         * Registers are not touched to try to keep this relatively arch
         * agnostic.
         */
        ret = ptrace(PTRACE_POKEDATA, tracee, info->poke_addr, 0x1001);
        EXPECT_EQ(0, ret);
}

FIXTURE(TRACE_poke) {
        struct sock_fprog prog;
        pid_t tracer;
        long poked;
        struct tracer_args_poke_t tracer_args;
};

FIXTURE_SETUP(TRACE_poke)
{
        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_TRACE | 0x1001),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };

        self->poked = 0;
        memset(&self->prog, 0, sizeof(self->prog));
        self->prog.filter = malloc(sizeof(filter));
        ASSERT_NE(NULL, self->prog.filter);
        memcpy(self->prog.filter, filter, sizeof(filter));
        self->prog.len = (unsigned short)ARRAY_SIZE(filter);

        /* Set up tracer args. */
        self->tracer_args.poke_addr = (unsigned long)&self->poked;

        /* Launch tracer. */
        self->tracer = setup_trace_fixture(_metadata, tracer_poke,
                                           &self->tracer_args, false);
}

FIXTURE_TEARDOWN(TRACE_poke)
{
        teardown_trace_fixture(_metadata, self->tracer);
        if (self->prog.filter)
                free(self->prog.filter);
}

TEST_F(TRACE_poke, read_has_side_effects)
{
        ssize_t ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
        ASSERT_EQ(0, ret);

        EXPECT_EQ(0, self->poked);
        ret = read(-1, NULL, 0);
        EXPECT_EQ(-1, ret);
        EXPECT_EQ(0x1001, self->poked);
}

TEST_F(TRACE_poke, getpid_runs_normally)
{
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
        ASSERT_EQ(0, ret);

        EXPECT_EQ(0, self->poked);
        EXPECT_NE(0, syscall(__NR_getpid));
        EXPECT_EQ(0, self->poked);
}

#if defined(__x86_64__)
# define ARCH_REGS              struct user_regs_struct
# define SYSCALL_NUM(_regs)     (_regs).orig_rax
# define SYSCALL_RET(_regs)     (_regs).rax
#elif defined(__i386__)
# define ARCH_REGS              struct user_regs_struct
# define SYSCALL_NUM(_regs)     (_regs).orig_eax
# define SYSCALL_RET(_regs)     (_regs).eax
#elif defined(__arm__)
# define ARCH_REGS              struct pt_regs
# define SYSCALL_NUM(_regs)     (_regs).ARM_r7
# ifndef PTRACE_SET_SYSCALL
#  define PTRACE_SET_SYSCALL   23
# endif
# define SYSCALL_NUM_SET(_regs, _nr)    \
                EXPECT_EQ(0, ptrace(PTRACE_SET_SYSCALL, tracee, NULL, _nr))
# define SYSCALL_RET(_regs)     (_regs).ARM_r0
#elif defined(__aarch64__)
# define ARCH_REGS              struct user_pt_regs
# define SYSCALL_NUM(_regs)     (_regs).regs[8]
# ifndef NT_ARM_SYSTEM_CALL
#  define NT_ARM_SYSTEM_CALL 0x404
# endif
# define SYSCALL_NUM_SET(_regs, _nr)                            \
        do {                                                    \
                struct iovec __v;                               \
                typeof(_nr) __nr = (_nr);                       \
                __v.iov_base = &__nr;                           \
                __v.iov_len = sizeof(__nr);                     \
                EXPECT_EQ(0, ptrace(PTRACE_SETREGSET, tracee,   \
                                    NT_ARM_SYSTEM_CALL, &__v)); \
        } while (0)
# define SYSCALL_RET(_regs)     (_regs).regs[0]
#elif defined(__loongarch__)
# define ARCH_REGS              struct user_pt_regs
# define SYSCALL_NUM(_regs)     (_regs).regs[11]
# define SYSCALL_RET(_regs)     (_regs).regs[4]
#elif defined(__riscv) && __riscv_xlen == 64
# define ARCH_REGS              struct user_regs_struct
# define SYSCALL_NUM(_regs)     (_regs).a7
# define SYSCALL_RET(_regs)     (_regs).a0
#elif defined(__csky__)
# define ARCH_REGS              struct pt_regs
#  if defined(__CSKYABIV2__)
#   define SYSCALL_NUM(_regs)   (_regs).regs[3]
#  else
#   define SYSCALL_NUM(_regs)   (_regs).regs[9]
#  endif
# define SYSCALL_RET(_regs)     (_regs).a0
#elif defined(__hppa__)
# define ARCH_REGS              struct user_regs_struct
# define SYSCALL_NUM(_regs)     (_regs).gr[20]
# define SYSCALL_RET(_regs)     (_regs).gr[28]
#elif defined(__powerpc__)
# define ARCH_REGS              struct pt_regs
# define SYSCALL_NUM(_regs)     (_regs).gpr[0]
# define SYSCALL_RET(_regs)     (_regs).gpr[3]
# define SYSCALL_RET_SET(_regs, _val)                           \
        do {                                                    \
                typeof(_val) _result = (_val);                  \
                if ((_regs.trap & 0xfff0) == 0x3000) {          \
                        /*                                      \
                         * scv 0 system call uses -ve result    \
                         * for error, so no need to adjust.     \
                         */                                     \
                        SYSCALL_RET(_regs) = _result;           \
                } else {                                        \
                        /*                                      \
                         * A syscall error is signaled by the   \
                         * CR0 SO bit and the code is stored as \
                         * a positive value.                    \
                         */                                     \
                        if (_result < 0) {                      \
                                SYSCALL_RET(_regs) = -_result;  \
                                (_regs).ccr |= 0x10000000;      \
                        } else {                                \
                                SYSCALL_RET(_regs) = _result;   \
                                (_regs).ccr &= ~0x10000000;     \
                        }                                       \
                }                                               \
        } while (0)
# define SYSCALL_RET_SET_ON_PTRACE_EXIT
#elif defined(__s390__)
# define ARCH_REGS              s390_regs
# define SYSCALL_NUM(_regs)     (_regs).gprs[2]
# define SYSCALL_RET_SET(_regs, _val)                   \
                TH_LOG("Can't modify syscall return on this architecture")
#elif defined(__mips__)
# include <asm/unistd_nr_n32.h>
# include <asm/unistd_nr_n64.h>
# include <asm/unistd_nr_o32.h>
# define ARCH_REGS              struct pt_regs
# define SYSCALL_NUM(_regs)                             \
        ({                                              \
                typeof((_regs).regs[2]) _nr;            \
                if ((_regs).regs[2] == __NR_O32_Linux)  \
                        _nr = (_regs).regs[4];          \
                else                                    \
                        _nr = (_regs).regs[2];          \
                _nr;                                    \
        })
# define SYSCALL_NUM_SET(_regs, _nr)                    \
        do {                                            \
                if ((_regs).regs[2] == __NR_O32_Linux)  \
                        (_regs).regs[4] = _nr;          \
                else                                    \
                        (_regs).regs[2] = _nr;          \
        } while (0)
# define SYSCALL_RET_SET(_regs, _val)                   \
                TH_LOG("Can't modify syscall return on this architecture")
#elif defined(__xtensa__)
# define ARCH_REGS              struct user_pt_regs
# define SYSCALL_NUM(_regs)     (_regs).syscall
/*
 * On xtensa syscall return value is in the register
 * a2 of the current window which is not fixed.
 */
#define SYSCALL_RET(_regs)      (_regs).a[(_regs).windowbase * 4 + 2]
#elif defined(__sh__)
# define ARCH_REGS              struct pt_regs
# define SYSCALL_NUM(_regs)     (_regs).regs[3]
# define SYSCALL_RET(_regs)     (_regs).regs[0]
#elif defined(__mc68000__)
# define ARCH_REGS              struct user_regs_struct
# define SYSCALL_NUM(_regs)     (_regs).orig_d0
# define SYSCALL_RET(_regs)     (_regs).d0
#else
# error "Do not know how to find your architecture's registers and syscalls"
#endif

/*
 * Most architectures can change the syscall by just updating the
 * associated register. This is the default if not defined above.
 */
#ifndef SYSCALL_NUM_SET
# define SYSCALL_NUM_SET(_regs, _nr)            \
        do {                                    \
                SYSCALL_NUM(_regs) = (_nr);     \
        } while (0)
#endif
/*
 * Most architectures can change the syscall return value by just
 * writing to the SYSCALL_RET register. This is the default if not
 * defined above. If an architecture cannot set the return value
 * (for example when the syscall and return value register is
 * shared), report it with TH_LOG() in an arch-specific definition
 * of SYSCALL_RET_SET() above, and leave SYSCALL_RET undefined.
 */
#if !defined(SYSCALL_RET) && !defined(SYSCALL_RET_SET)
# error "One of SYSCALL_RET or SYSCALL_RET_SET is needed for this arch"
#endif
#ifndef SYSCALL_RET_SET
# define SYSCALL_RET_SET(_regs, _val)           \
        do {                                    \
                SYSCALL_RET(_regs) = (_val);    \
        } while (0)
#endif

/* When the syscall return can't be changed, stub out the tests for it. */
#ifndef SYSCALL_RET
# define EXPECT_SYSCALL_RETURN(val, action)     EXPECT_EQ(-1, action)
#else
# define EXPECT_SYSCALL_RETURN(val, action)             \
        do {                                            \
                errno = 0;                              \
                if (val < 0) {                          \
                        EXPECT_EQ(-1, action);          \
                        EXPECT_EQ(-(val), errno);       \
                } else {                                \
                        EXPECT_EQ(val, action);         \
                }                                       \
        } while (0)
#endif

/*
 * Some architectures (e.g. powerpc) can only set syscall
 * return values on syscall exit during ptrace.
 */
const bool ptrace_entry_set_syscall_nr = true;
const bool ptrace_entry_set_syscall_ret =
#ifndef SYSCALL_RET_SET_ON_PTRACE_EXIT
        true;
#else
        false;
#endif

/*
 * Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
 * architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
 */
#if defined(__x86_64__) || defined(__i386__) || defined(__mips__) || defined(__mc68000__)
# define ARCH_GETREGS(_regs)    ptrace(PTRACE_GETREGS, tracee, 0, &(_regs))
# define ARCH_SETREGS(_regs)    ptrace(PTRACE_SETREGS, tracee, 0, &(_regs))
#else
# define ARCH_GETREGS(_regs)    ({                                      \
                struct iovec __v;                                       \
                __v.iov_base = &(_regs);                                \
                __v.iov_len = sizeof(_regs);                            \
                ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &__v);    \
        })
# define ARCH_SETREGS(_regs)    ({                                      \
                struct iovec __v;                                       \
                __v.iov_base = &(_regs);                                \
                __v.iov_len = sizeof(_regs);                            \
                ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &__v);    \
        })
#endif

/* Architecture-specific syscall fetching routine. */
int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
{
        ARCH_REGS regs;

        EXPECT_EQ(0, ARCH_GETREGS(regs)) {
                return -1;
        }

        return SYSCALL_NUM(regs);
}

/* Architecture-specific syscall changing routine. */
void __change_syscall(struct __test_metadata *_metadata,
                    pid_t tracee, long *syscall, long *ret)
{
        ARCH_REGS orig, regs;

        /* Do not get/set registers if we have nothing to do. */
        if (!syscall && !ret)
                return;

        EXPECT_EQ(0, ARCH_GETREGS(regs)) {
                return;
        }
        orig = regs;

        if (syscall)
                SYSCALL_NUM_SET(regs, *syscall);

        if (ret)
                SYSCALL_RET_SET(regs, *ret);

        /* Flush any register changes made. */
        if (memcmp(&orig, &regs, sizeof(orig)) != 0)
                EXPECT_EQ(0, ARCH_SETREGS(regs));
}

/* Change only syscall number. */
void change_syscall_nr(struct __test_metadata *_metadata,
                       pid_t tracee, long syscall)
{
        __change_syscall(_metadata, tracee, &syscall, NULL);
}

/* Change syscall return value (and set syscall number to -1). */
void change_syscall_ret(struct __test_metadata *_metadata,
                        pid_t tracee, long ret)
{
        long syscall = -1;

        __change_syscall(_metadata, tracee, &syscall, &ret);
}

void tracer_seccomp(struct __test_metadata *_metadata, pid_t tracee,
                    int status, void *args)
{
        int ret;
        unsigned long msg;

        EXPECT_EQ(PTRACE_EVENT_MASK(status), PTRACE_EVENT_SECCOMP) {
                TH_LOG("Unexpected ptrace event: %d", PTRACE_EVENT_MASK(status));
                return;
        }

        /* Make sure we got the right message. */
        ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
        EXPECT_EQ(0, ret);

        /* Validate and take action on expected syscalls. */
        switch (msg) {
        case 0x1002:
                /* change getpid to getppid. */
                EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee));
                change_syscall_nr(_metadata, tracee, __NR_getppid);
                break;
        case 0x1003:
                /* skip gettid with valid return code. */
                EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
                change_syscall_ret(_metadata, tracee, 45000);
                break;
        case 0x1004:
                /* skip openat with error. */
                EXPECT_EQ(__NR_openat, get_syscall(_metadata, tracee));
                change_syscall_ret(_metadata, tracee, -ESRCH);
                break;
        case 0x1005:
                /* do nothing (allow getppid) */
                EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee));
                break;
        default:
                EXPECT_EQ(0, msg) {
                        TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg);
                        kill(tracee, SIGKILL);
                }
        }

}

FIXTURE(TRACE_syscall) {
        struct sock_fprog prog;
        pid_t tracer, mytid, mypid, parent;
        long syscall_nr;
};

void tracer_ptrace(struct __test_metadata *_metadata, pid_t tracee,
                   int status, void *args)
{
        int ret;
        unsigned long msg;
        static bool entry;
        long syscall_nr_val, syscall_ret_val;
        long *syscall_nr = NULL, *syscall_ret = NULL;
        FIXTURE_DATA(TRACE_syscall) *self = args;

        EXPECT_EQ(WSTOPSIG(status) & 0x80, 0x80) {
                TH_LOG("Unexpected WSTOPSIG: %d", WSTOPSIG(status));
                return;
        }

        /*
         * The traditional way to tell PTRACE_SYSCALL entry/exit
         * is by counting.
         */
        entry = !entry;

        /* Make sure we got an appropriate message. */
        ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
        EXPECT_EQ(0, ret);
        EXPECT_EQ(entry ? PTRACE_EVENTMSG_SYSCALL_ENTRY
                        : PTRACE_EVENTMSG_SYSCALL_EXIT, msg);

        /*
         * Some architectures only support setting return values during
         * syscall exit under ptrace, and on exit the syscall number may
         * no longer be available. Therefore, save the initial sycall
         * number here, so it can be examined during both entry and exit
         * phases.
         */
        if (entry)
                self->syscall_nr = get_syscall(_metadata, tracee);

        /*
         * Depending on the architecture's syscall setting abilities, we
         * pick which things to set during this phase (entry or exit).
         */
        if (entry == ptrace_entry_set_syscall_nr)
                syscall_nr = &syscall_nr_val;
        if (entry == ptrace_entry_set_syscall_ret)
                syscall_ret = &syscall_ret_val;

        /* Now handle the actual rewriting cases. */
        switch (self->syscall_nr) {
        case __NR_getpid:
                syscall_nr_val = __NR_getppid;
                /* Never change syscall return for this case. */
                syscall_ret = NULL;
                break;
        case __NR_gettid:
                syscall_nr_val = -1;
                syscall_ret_val = 45000;
                break;
        case __NR_openat:
                syscall_nr_val = -1;
                syscall_ret_val = -ESRCH;
                break;
        default:
                /* Unhandled, do nothing. */
                return;
        }

        __change_syscall(_metadata, tracee, syscall_nr, syscall_ret);
}

FIXTURE_VARIANT(TRACE_syscall) {
        /*
         * All of the SECCOMP_RET_TRACE behaviors can be tested with either
         * SECCOMP_RET_TRACE+PTRACE_CONT or plain ptrace()+PTRACE_SYSCALL.
         * This indicates if we should use SECCOMP_RET_TRACE (false), or
         * ptrace (true).
         */
        bool use_ptrace;
};

FIXTURE_VARIANT_ADD(TRACE_syscall, ptrace) {
        .use_ptrace = true,
};

FIXTURE_VARIANT_ADD(TRACE_syscall, seccomp) {
        .use_ptrace = false,
};

FIXTURE_SETUP(TRACE_syscall)
{
        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_getpid, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_openat, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1005),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        /* Prepare some testable syscall results. */
        self->mytid = syscall(__NR_gettid);
        ASSERT_GT(self->mytid, 0);
        ASSERT_NE(self->mytid, 1) {
                TH_LOG("Running this test as init is not supported. :)");
        }

        self->mypid = getpid();
        ASSERT_GT(self->mypid, 0);
        ASSERT_EQ(self->mytid, self->mypid);

        self->parent = getppid();
        ASSERT_GT(self->parent, 0);
        ASSERT_NE(self->parent, self->mypid);

        /* Launch tracer. */
        self->tracer = setup_trace_fixture(_metadata,
                                           variant->use_ptrace ? tracer_ptrace
                                                               : tracer_seccomp,
                                           self, variant->use_ptrace);

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret);

        /* Do not install seccomp rewrite filters, as we'll use ptrace instead. */
        if (variant->use_ptrace)
                return;

        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        ASSERT_EQ(0, ret);
}

FIXTURE_TEARDOWN(TRACE_syscall)
{
        teardown_trace_fixture(_metadata, self->tracer);
}

TEST(negative_ENOSYS)
{
#if defined(__arm__)
        SKIP(return, "arm32 does not support calling syscall -1");
#endif
        /*
         * 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, negative_ENOSYS)
{
        negative_ENOSYS(_metadata);
}

TEST_F(TRACE_syscall, syscall_allowed)
{
        /* getppid works as expected (no changes). */
        EXPECT_EQ(self->parent, syscall(__NR_getppid));
        EXPECT_NE(self->mypid, syscall(__NR_getppid));
}

TEST_F(TRACE_syscall, syscall_redirected)
{
        /* getpid has been redirected to getppid as expected. */
        EXPECT_EQ(self->parent, syscall(__NR_getpid));
        EXPECT_NE(self->mypid, syscall(__NR_getpid));
}

TEST_F(TRACE_syscall, syscall_errno)
{
        /* Tracer should skip the open syscall, resulting in ESRCH. */
        EXPECT_SYSCALL_RETURN(-ESRCH, syscall(__NR_openat));
}

TEST_F(TRACE_syscall, syscall_faked)
{
        /* Tracer skips the gettid syscall and store altered return value. */
        EXPECT_SYSCALL_RETURN(45000, syscall(__NR_gettid));
}

TEST_F_SIGNAL(TRACE_syscall, kill_immediate, SIGSYS)
{
        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_mknodat, 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 = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        /* Install "kill on mknodat" filter. */
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        ASSERT_EQ(0, ret);

        /* This should immediately die with SIGSYS, regardless of tracer. */
        EXPECT_EQ(-1, syscall(__NR_mknodat, -1, NULL, 0, 0));
}

TEST_F(TRACE_syscall, skip_after)
{
        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_getppid, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        /* Install additional "errno on getppid" filter. */
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        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);
}

TEST_F_SIGNAL(TRACE_syscall, kill_after, SIGSYS)
{
        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_getppid, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        /* Install additional "death on getppid" filter. */
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
        ASSERT_EQ(0, ret);

        /* Tracer will redirect getpid to getppid, and we should die. */
        EXPECT_NE(self->mypid, syscall(__NR_getpid));
}

TEST(seccomp_syscall)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        /* Reject insane operation. */
        ret = seccomp(-1, 0, &prog);
        ASSERT_NE(ENOSYS, errno) {
                TH_LOG("Kernel does not support seccomp syscall!");
        }
        EXPECT_EQ(EINVAL, errno) {
                TH_LOG("Did not reject crazy op value!");
        }

        /* Reject strict with flags or pointer. */
        ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL);
        EXPECT_EQ(EINVAL, errno) {
                TH_LOG("Did not reject mode strict with flags!");
        }
        ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog);
        EXPECT_EQ(EINVAL, errno) {
                TH_LOG("Did not reject mode strict with uargs!");
        }

        /* Reject insane args for filter. */
        ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog);
        EXPECT_EQ(EINVAL, errno) {
                TH_LOG("Did not reject crazy filter flags!");
        }
        ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL);
        EXPECT_EQ(EFAULT, errno) {
                TH_LOG("Did not reject NULL filter!");
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
        EXPECT_EQ(0, errno) {
                TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s",
                        strerror(errno));
        }
}

TEST(seccomp_syscall_mode_lock)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
        ASSERT_NE(ENOSYS, errno) {
                TH_LOG("Kernel does not support seccomp syscall!");
        }
        EXPECT_EQ(0, ret) {
                TH_LOG("Could not install filter!");
        }

        /* Make sure neither entry point will switch to strict. */
        ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0);
        EXPECT_EQ(EINVAL, errno) {
                TH_LOG("Switched to mode strict!");
        }

        ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL);
        EXPECT_EQ(EINVAL, errno) {
                TH_LOG("Switched to mode strict!");
        }
}

/*
 * 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,
                                 SECCOMP_FILTER_FLAG_SPEC_ALLOW,
                                 SECCOMP_FILTER_FLAG_NEW_LISTENER,
                                 SECCOMP_FILTER_FLAG_TSYNC_ESRCH };
        unsigned int exclusive[] = {
                                SECCOMP_FILTER_FLAG_TSYNC,
                                SECCOMP_FILTER_FLAG_NEW_LISTENER };
        unsigned int flag, all_flags, exclusive_mask;
        int i;
        long ret;

        /* Test detection of individual known-good filter flags */
        for (i = 0, all_flags = 0; i < ARRAY_SIZE(flags); i++) {
                int bits = 0;

                flag = flags[i];
                /* Make sure the flag is a single bit! */
                while (flag) {
                        if (flag & 0x1)
                                bits ++;
                        flag >>= 1;
                }
                ASSERT_EQ(1, bits);
                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 combined. But
         * for the exclusive flags we need to mask them out and try them
         * individually for the "all flags" testing.
         */
        exclusive_mask = 0;
        for (i = 0; i < ARRAY_SIZE(exclusive); i++)
                exclusive_mask |= exclusive[i];
        for (i = 0; i < ARRAY_SIZE(exclusive); i++) {
                flag = all_flags & ~exclusive_mask;
                flag |= exclusive[i];

                ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
                EXPECT_EQ(-1, ret);
                EXPECT_EQ(EFAULT, errno) {
                        TH_LOG("Failed to detect that all known-good filter flags (0x%X) are supported!",
                               flag);
                }
        }

        /* Test detection of an unknown filter flags, without exclusives. */
        flag = -1;
        flag &= ~exclusive_mask;
        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[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
                      &prog);
        ASSERT_NE(ENOSYS, errno) {
                TH_LOG("Kernel does not support seccomp syscall!");
        }
        EXPECT_EQ(0, ret) {
                TH_LOG("Could not install initial filter with TSYNC!");
        }
}

#define TSYNC_SIBLINGS 2
struct tsync_sibling {
        pthread_t tid;
        pid_t system_tid;
        sem_t *started;
        pthread_cond_t *cond;
        pthread_mutex_t *mutex;
        int diverge;
        int num_waits;
        struct sock_fprog *prog;
        struct __test_metadata *metadata;
};

/*
 * To avoid joining joined threads (which is not allowed by Bionic),
 * make sure we both successfully join and clear the tid to skip a
 * later join attempt during fixture teardown. Any remaining threads
 * will be directly killed during teardown.
 */
#define PTHREAD_JOIN(tid, status)                                       \
        do {                                                            \
                int _rc = pthread_join(tid, status);                    \
                if (_rc) {                                              \
                        TH_LOG("pthread_join of tid %u failed: %d\n",   \
                                (unsigned int)tid, _rc);                \
                } else {                                                \
                        tid = 0;                                        \
                }                                                       \
        } while (0)

FIXTURE(TSYNC) {
        struct sock_fprog root_prog, apply_prog;
        struct tsync_sibling sibling[TSYNC_SIBLINGS];
        sem_t started;
        pthread_cond_t cond;
        pthread_mutex_t mutex;
        int sibling_count;
};

FIXTURE_SETUP(TSYNC)
{
        struct sock_filter root_filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_filter apply_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_KILL),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };

        memset(&self->root_prog, 0, sizeof(self->root_prog));
        memset(&self->apply_prog, 0, sizeof(self->apply_prog));
        memset(&self->sibling, 0, sizeof(self->sibling));
        self->root_prog.filter = malloc(sizeof(root_filter));
        ASSERT_NE(NULL, self->root_prog.filter);
        memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter));
        self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter);

        self->apply_prog.filter = malloc(sizeof(apply_filter));
        ASSERT_NE(NULL, self->apply_prog.filter);
        memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter));
        self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter);

        self->sibling_count = 0;
        pthread_mutex_init(&self->mutex, NULL);
        pthread_cond_init(&self->cond, NULL);
        sem_init(&self->started, 0, 0);
        self->sibling[0].tid = 0;
        self->sibling[0].cond = &self->cond;
        self->sibling[0].started = &self->started;
        self->sibling[0].mutex = &self->mutex;
        self->sibling[0].diverge = 0;
        self->sibling[0].num_waits = 1;
        self->sibling[0].prog = &self->root_prog;
        self->sibling[0].metadata = _metadata;
        self->sibling[1].tid = 0;
        self->sibling[1].cond = &self->cond;
        self->sibling[1].started = &self->started;
        self->sibling[1].mutex = &self->mutex;
        self->sibling[1].diverge = 0;
        self->sibling[1].prog = &self->root_prog;
        self->sibling[1].num_waits = 1;
        self->sibling[1].metadata = _metadata;
}

FIXTURE_TEARDOWN(TSYNC)
{
        int sib = 0;

        if (self->root_prog.filter)
                free(self->root_prog.filter);
        if (self->apply_prog.filter)
                free(self->apply_prog.filter);

        for ( ; sib < self->sibling_count; ++sib) {
                struct tsync_sibling *s = &self->sibling[sib];

                if (!s->tid)
                        continue;
                /*
                 * If a thread is still running, it may be stuck, so hit
                 * it over the head really hard.
                 */
                pthread_kill(s->tid, 9);
        }
        pthread_mutex_destroy(&self->mutex);
        pthread_cond_destroy(&self->cond);
        sem_destroy(&self->started);
}

void *tsync_sibling(void *data)
{
        long ret = 0;
        struct tsync_sibling *me = data;

        me->system_tid = syscall(__NR_gettid);

        pthread_mutex_lock(me->mutex);
        if (me->diverge) {
                /* Just re-apply the root prog to fork the tree */
                ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
                                me->prog, 0, 0);
        }
        sem_post(me->started);
        /* Return outside of started so parent notices failures. */
        if (ret) {
                pthread_mutex_unlock(me->mutex);
                return (void *)SIBLING_EXIT_FAILURE;
        }
        do {
                pthread_cond_wait(me->cond, me->mutex);
                me->num_waits = me->num_waits - 1;
        } while (me->num_waits);
        pthread_mutex_unlock(me->mutex);

        ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
        if (!ret)
                return (void *)SIBLING_EXIT_NEWPRIVS;
        read(-1, NULL, 0);
        return (void *)SIBLING_EXIT_UNKILLED;
}

void tsync_start_sibling(struct tsync_sibling *sibling)
{
        pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling);
}

TEST_F(TSYNC, siblings_fail_prctl)
{
        long ret;
        void *status;
        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_prctl, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };

        ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        /* Check prctl failure detection by requesting sib 0 diverge. */
        ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
        ASSERT_NE(ENOSYS, errno) {
                TH_LOG("Kernel does not support seccomp syscall!");
        }
        ASSERT_EQ(0, ret) {
                TH_LOG("setting filter failed");
        }

        self->sibling[0].diverge = 1;
        tsync_start_sibling(&self->sibling[0]);
        tsync_start_sibling(&self->sibling[1]);

        while (self->sibling_count < TSYNC_SIBLINGS) {
                sem_wait(&self->started);
                self->sibling_count++;
        }

        /* Signal the threads to clean up*/
        pthread_mutex_lock(&self->mutex);
        ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
                TH_LOG("cond broadcast non-zero");
        }
        pthread_mutex_unlock(&self->mutex);

        /* Ensure diverging sibling failed to call prctl. */
        PTHREAD_JOIN(self->sibling[0].tid, &status);
        EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status);
        PTHREAD_JOIN(self->sibling[1].tid, &status);
        EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
}

TEST_F(TSYNC, two_siblings_with_ancestor)
{
        long ret;
        void *status;

        ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
        ASSERT_NE(ENOSYS, errno) {
                TH_LOG("Kernel does not support seccomp syscall!");
        }
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
        }
        tsync_start_sibling(&self->sibling[0]);
        tsync_start_sibling(&self->sibling[1]);

        while (self->sibling_count < TSYNC_SIBLINGS) {
                sem_wait(&self->started);
                self->sibling_count++;
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
                      &self->apply_prog);
        ASSERT_EQ(0, ret) {
                TH_LOG("Could install filter on all threads!");
        }
        /* Tell the siblings to test the policy */
        pthread_mutex_lock(&self->mutex);
        ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
                TH_LOG("cond broadcast non-zero");
        }
        pthread_mutex_unlock(&self->mutex);
        /* Ensure they are both killed and don't exit cleanly. */
        PTHREAD_JOIN(self->sibling[0].tid, &status);
        EXPECT_EQ(0x0, (long)status);
        PTHREAD_JOIN(self->sibling[1].tid, &status);
        EXPECT_EQ(0x0, (long)status);
}

TEST_F(TSYNC, two_sibling_want_nnp)
{
        void *status;

        /* start siblings before any prctl() operations */
        tsync_start_sibling(&self->sibling[0]);
        tsync_start_sibling(&self->sibling[1]);
        while (self->sibling_count < TSYNC_SIBLINGS) {
                sem_wait(&self->started);
                self->sibling_count++;
        }

        /* Tell the siblings to test no policy */
        pthread_mutex_lock(&self->mutex);
        ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
                TH_LOG("cond broadcast non-zero");
        }
        pthread_mutex_unlock(&self->mutex);

        /* Ensure they are both upset about lacking nnp. */
        PTHREAD_JOIN(self->sibling[0].tid, &status);
        EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
        PTHREAD_JOIN(self->sibling[1].tid, &status);
        EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
}

TEST_F(TSYNC, two_siblings_with_no_filter)
{
        long ret;
        void *status;

        /* start siblings before any prctl() operations */
        tsync_start_sibling(&self->sibling[0]);
        tsync_start_sibling(&self->sibling[1]);
        while (self->sibling_count < TSYNC_SIBLINGS) {
                sem_wait(&self->started);
                self->sibling_count++;
        }

        ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
                      &self->apply_prog);
        ASSERT_NE(ENOSYS, errno) {
                TH_LOG("Kernel does not support seccomp syscall!");
        }
        ASSERT_EQ(0, ret) {
                TH_LOG("Could install filter on all threads!");
        }

        /* Tell the siblings to test the policy */
        pthread_mutex_lock(&self->mutex);
        ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
                TH_LOG("cond broadcast non-zero");
        }
        pthread_mutex_unlock(&self->mutex);

        /* Ensure they are both killed and don't exit cleanly. */
        PTHREAD_JOIN(self->sibling[0].tid, &status);
        EXPECT_EQ(0x0, (long)status);
        PTHREAD_JOIN(self->sibling[1].tid, &status);
        EXPECT_EQ(0x0, (long)status);
}

TEST_F(TSYNC, two_siblings_with_one_divergence)
{
        long ret;
        void *status;

        ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
        ASSERT_NE(ENOSYS, errno) {
                TH_LOG("Kernel does not support seccomp syscall!");
        }
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
        }
        self->sibling[0].diverge = 1;
        tsync_start_sibling(&self->sibling[0]);
        tsync_start_sibling(&self->sibling[1]);

        while (self->sibling_count < TSYNC_SIBLINGS) {
                sem_wait(&self->started);
                self->sibling_count++;
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
                      &self->apply_prog);
        ASSERT_EQ(self->sibling[0].system_tid, ret) {
                TH_LOG("Did not fail on diverged sibling.");
        }

        /* Wake the threads */
        pthread_mutex_lock(&self->mutex);
        ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
                TH_LOG("cond broadcast non-zero");
        }
        pthread_mutex_unlock(&self->mutex);

        /* Ensure they are both unkilled. */
        PTHREAD_JOIN(self->sibling[0].tid, &status);
        EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
        PTHREAD_JOIN(self->sibling[1].tid, &status);
        EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
}

TEST_F(TSYNC, two_siblings_with_one_divergence_no_tid_in_err)
{
        long ret, flags;
        void *status;

        ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
        ASSERT_NE(ENOSYS, errno) {
                TH_LOG("Kernel does not support seccomp syscall!");
        }
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
        }
        self->sibling[0].diverge = 1;
        tsync_start_sibling(&self->sibling[0]);
        tsync_start_sibling(&self->sibling[1]);

        while (self->sibling_count < TSYNC_SIBLINGS) {
                sem_wait(&self->started);
                self->sibling_count++;
        }

        flags = SECCOMP_FILTER_FLAG_TSYNC | \
                SECCOMP_FILTER_FLAG_TSYNC_ESRCH;
        ret = seccomp(SECCOMP_SET_MODE_FILTER, flags, &self->apply_prog);
        ASSERT_EQ(ESRCH, errno) {
                TH_LOG("Did not return ESRCH for diverged sibling.");
        }
        ASSERT_EQ(-1, ret) {
                TH_LOG("Did not fail on diverged sibling.");
        }

        /* Wake the threads */
        pthread_mutex_lock(&self->mutex);
        ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
                TH_LOG("cond broadcast non-zero");
        }
        pthread_mutex_unlock(&self->mutex);

        /* Ensure they are both unkilled. */
        PTHREAD_JOIN(self->sibling[0].tid, &status);
        EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
        PTHREAD_JOIN(self->sibling[1].tid, &status);
        EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
}

TEST_F(TSYNC, two_siblings_not_under_filter)
{
        long ret, sib;
        void *status;
        struct timespec delay = { .tv_nsec = 100000000 };

        ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        /*
         * Sibling 0 will have its own seccomp policy
         * and Sibling 1 will not be under seccomp at
         * all. Sibling 1 will enter seccomp and 0
         * will cause failure.
         */
        self->sibling[0].diverge = 1;
        tsync_start_sibling(&self->sibling[0]);
        tsync_start_sibling(&self->sibling[1]);

        while (self->sibling_count < TSYNC_SIBLINGS) {
                sem_wait(&self->started);
                self->sibling_count++;
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
        ASSERT_NE(ENOSYS, errno) {
                TH_LOG("Kernel does not support seccomp syscall!");
        }
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
        }

        ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
                      &self->apply_prog);
        ASSERT_EQ(ret, self->sibling[0].system_tid) {
                TH_LOG("Did not fail on diverged sibling.");
        }
        sib = 1;
        if (ret == self->sibling[0].system_tid)
                sib = 0;

        pthread_mutex_lock(&self->mutex);

        /* Increment the other siblings num_waits so we can clean up
         * the one we just saw.
         */
        self->sibling[!sib].num_waits += 1;

        /* Signal the thread to clean up*/
        ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
                TH_LOG("cond broadcast non-zero");
        }
        pthread_mutex_unlock(&self->mutex);
        PTHREAD_JOIN(self->sibling[sib].tid, &status);
        EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
        /* Poll for actual task death. pthread_join doesn't guarantee it. */
        while (!kill(self->sibling[sib].system_tid, 0))
                nanosleep(&delay, NULL);
        /* Switch to the remaining sibling */
        sib = !sib;

        ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
                      &self->apply_prog);
        ASSERT_EQ(0, ret) {
                TH_LOG("Expected the remaining sibling to sync");
        };

        pthread_mutex_lock(&self->mutex);

        /* If remaining sibling didn't have a chance to wake up during
         * the first broadcast, manually reduce the num_waits now.
         */
        if (self->sibling[sib].num_waits > 1)
                self->sibling[sib].num_waits = 1;
        ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
                TH_LOG("cond broadcast non-zero");
        }
        pthread_mutex_unlock(&self->mutex);
        PTHREAD_JOIN(self->sibling[sib].tid, &status);
        EXPECT_EQ(0, (long)status);
        /* Poll for actual task death. pthread_join doesn't guarantee it. */
        while (!kill(self->sibling[sib].system_tid, 0))
                nanosleep(&delay, NULL);

        ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
                      &self->apply_prog);
        ASSERT_EQ(0, ret);  /* just us chickens */
}

/* Make sure restarted syscalls are seen directly as "restart_syscall". */
TEST(syscall_restart)
{
        long ret;
        unsigned long msg;
        pid_t child_pid;
        int pipefd[2];
        int status;
        siginfo_t info = { };
        struct sock_filter filter[] = {
                BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
                         offsetof(struct seccomp_data, nr)),

#ifdef __NR_sigreturn
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 7, 0),
#endif
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 6, 0),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 5, 0),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 4, 0),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 5, 0),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_clock_nanosleep, 4, 0),
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0),

                /* Allow __NR_write for easy logging. */
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
                /* The nanosleep jump target. */
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100),
                /* The restart_syscall jump target. */
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };
#if defined(__arm__)
        struct utsname utsbuf;
#endif

        ASSERT_EQ(0, pipe(pipefd));

        child_pid = fork();
        ASSERT_LE(0, child_pid);
        if (child_pid == 0) {
                /* Child uses EXPECT not ASSERT to deliver status correctly. */
                char buf = ' ';
                struct timespec timeout = { };

                /* Attach parent as tracer and stop. */
                EXPECT_EQ(0, ptrace(PTRACE_TRACEME));
                EXPECT_EQ(0, raise(SIGSTOP));

                EXPECT_EQ(0, close(pipefd[1]));

                EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
                        TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
                }

                ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
                EXPECT_EQ(0, ret) {
                        TH_LOG("Failed to install filter!");
                }

                EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
                        TH_LOG("Failed to read() sync from parent");
                }
                EXPECT_EQ('.', buf) {
                        TH_LOG("Failed to get sync data from read()");
                }

                /* Start nanosleep to be interrupted. */
                timeout.tv_sec = 1;
                errno = 0;
                EXPECT_EQ(0, nanosleep(&timeout, NULL)) {
                        TH_LOG("Call to nanosleep() failed (errno %d: %s)",
                                errno, strerror(errno));
                }

                /* Read final sync from parent. */
                EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
                        TH_LOG("Failed final read() from parent");
                }
                EXPECT_EQ('!', buf) {
                        TH_LOG("Failed to get final data from read()");
                }

                /* Directly report the status of our test harness results. */
                syscall(__NR_exit, _metadata->exit_code);
        }
        EXPECT_EQ(0, close(pipefd[0]));

        /* Attach to child, setup options, and release. */
        ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
        ASSERT_EQ(true, WIFSTOPPED(status));
        ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL,
                            PTRACE_O_TRACESECCOMP));
        ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
        ASSERT_EQ(1, write(pipefd[1], ".", 1));

        /* Wait for nanosleep() to start. */
        ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
        ASSERT_EQ(true, WIFSTOPPED(status));
        ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
        ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
        ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
        ASSERT_EQ(0x100, msg);
        ret = get_syscall(_metadata, child_pid);
        EXPECT_TRUE(ret == __NR_nanosleep || ret == __NR_clock_nanosleep);

        /* Might as well check siginfo for sanity while we're here. */
        ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
        ASSERT_EQ(SIGTRAP, info.si_signo);
        ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code);
        EXPECT_EQ(0, info.si_errno);
        EXPECT_EQ(getuid(), info.si_uid);
        /* Verify signal delivery came from child (seccomp-triggered). */
        EXPECT_EQ(child_pid, info.si_pid);

        /* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */
        ASSERT_EQ(0, kill(child_pid, SIGSTOP));
        ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
        ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
        ASSERT_EQ(true, WIFSTOPPED(status));
        ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
        ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
        /*
         * There is no siginfo on SIGSTOP any more, so we can't verify
         * signal delivery came from parent now (getpid() == info.si_pid).
         * https://lkml.kernel.org/r/CAGXu5jJaZAOzP1qFz66tYrtbuywqb+UN2SOA1VLHpCCOiYvYeg@mail.gmail.com
         * At least verify the SIGSTOP via PTRACE_GETSIGINFO.
         */
        EXPECT_EQ(SIGSTOP, info.si_signo);

        /* Restart nanosleep with SIGCONT, which triggers restart_syscall. */
        ASSERT_EQ(0, kill(child_pid, SIGCONT));
        ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
        ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
        ASSERT_EQ(true, WIFSTOPPED(status));
        ASSERT_EQ(SIGCONT, WSTOPSIG(status));
        ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));

        /* Wait for restart_syscall() to start. */
        ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
        ASSERT_EQ(true, WIFSTOPPED(status));
        ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
        ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
        ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));

        ASSERT_EQ(0x200, msg);
        ret = get_syscall(_metadata, child_pid);
#if defined(__arm__)
        /*
         * - native ARM registers do NOT expose true syscall.
         * - compat ARM registers on ARM64 DO expose true syscall.
         * - values of utsbuf.machine include 'armv8l' or 'armb8b'
         *   for ARM64 running in compat mode.
         */
        ASSERT_EQ(0, uname(&utsbuf));
        if ((strncmp(utsbuf.machine, "arm", 3) == 0) &&
            (strncmp(utsbuf.machine, "armv8l", 6) != 0) &&
            (strncmp(utsbuf.machine, "armv8b", 6) != 0)) {
                EXPECT_EQ(__NR_nanosleep, ret);
        } else
#endif
        {
                EXPECT_EQ(__NR_restart_syscall, ret);
        }

        /* Write again to end test. */
        ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
        ASSERT_EQ(1, write(pipefd[1], "!", 1));
        EXPECT_EQ(0, close(pipefd[1]));

        ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
        if (WIFSIGNALED(status) || WEXITSTATUS(status))
                _metadata->exit_code = KSFT_FAIL;
}

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);
}

TEST(get_metadata)
{
        pid_t pid;
        int pipefd[2];
        char buf;
        struct seccomp_metadata md;
        long ret;

        /* Only real root can get metadata. */
        if (geteuid()) {
                SKIP(return, "get_metadata requires real root");
                return;
        }

        ASSERT_EQ(0, pipe(pipefd));

        pid = fork();
        ASSERT_GE(pid, 0);
        if (pid == 0) {
                struct sock_filter filter[] = {
                        BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
                };
                struct sock_fprog prog = {
                        .len = (unsigned short)ARRAY_SIZE(filter),
                        .filter = filter,
                };

                /* one with log, one without */
                EXPECT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER,
                                     SECCOMP_FILTER_FLAG_LOG, &prog));
                EXPECT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog));

                EXPECT_EQ(0, close(pipefd[0]));
                ASSERT_EQ(1, write(pipefd[1], "1", 1));
                ASSERT_EQ(0, close(pipefd[1]));

                while (1)
                        sleep(100);
        }

        ASSERT_EQ(0, close(pipefd[1]));
        ASSERT_EQ(1, read(pipefd[0], &buf, 1));

        ASSERT_EQ(0, ptrace(PTRACE_ATTACH, pid));
        ASSERT_EQ(pid, waitpid(pid, NULL, 0));

        /* Past here must not use ASSERT or child process is never killed. */

        md.filter_off = 0;
        errno = 0;
        ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
        EXPECT_EQ(sizeof(md), ret) {
                if (errno == EINVAL)
                        SKIP(goto skip, "Kernel does not support PTRACE_SECCOMP_GET_METADATA (missing CONFIG_CHECKPOINT_RESTORE?)");
        }

        EXPECT_EQ(md.flags, SECCOMP_FILTER_FLAG_LOG);
        EXPECT_EQ(md.filter_off, 0);

        md.filter_off = 1;
        ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
        EXPECT_EQ(sizeof(md), ret);
        EXPECT_EQ(md.flags, 0);
        EXPECT_EQ(md.filter_off, 1);

skip:
        ASSERT_EQ(0, kill(pid, SIGKILL));
}

static int user_notif_syscall(int nr, unsigned int flags)
{
        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, 0, 1),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_USER_NOTIF),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };

        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };

        return seccomp(SECCOMP_SET_MODE_FILTER, flags, &prog);
}

#define USER_NOTIF_MAGIC INT_MAX
TEST(user_notification_basic)
{
        pid_t pid;
        long ret;
        int status, listener;
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};
        struct pollfd pollfd;

        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        pid = fork();
        ASSERT_GE(pid, 0);

        /* Check that we get -ENOSYS with no listener attached */
        if (pid == 0) {
                if (user_notif_syscall(__NR_getppid, 0) < 0)
                        exit(1);
                ret = syscall(__NR_getppid);
                exit(ret >= 0 || errno != ENOSYS);
        }

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));

        /* Add some no-op filters for grins. */
        EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
        EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
        EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
        EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);

        /* Check that the basic notification machinery works */
        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        /* Installing a second listener in the chain should EBUSY */
        EXPECT_EQ(user_notif_syscall(__NR_getppid,
                                     SECCOMP_FILTER_FLAG_NEW_LISTENER),
                  -1);
        EXPECT_EQ(errno, EBUSY);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                ret = syscall(__NR_getppid);
                exit(ret != USER_NOTIF_MAGIC);
        }

        pollfd.fd = listener;
        pollfd.events = POLLIN | POLLOUT;

        EXPECT_GT(poll(&pollfd, 1, -1), 0);
        EXPECT_EQ(pollfd.revents, POLLIN);

        /* Test that we can't pass garbage to the kernel. */
        memset(&req, 0, sizeof(req));
        req.pid = -1;
        errno = 0;
        ret = ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req);
        EXPECT_EQ(-1, ret);
        EXPECT_EQ(EINVAL, errno);

        if (ret) {
                req.pid = 0;
                EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
        }

        pollfd.fd = listener;
        pollfd.events = POLLIN | POLLOUT;

        EXPECT_GT(poll(&pollfd, 1, -1), 0);
        EXPECT_EQ(pollfd.revents, POLLOUT);

        EXPECT_EQ(req.data.nr,  __NR_getppid);

        resp.id = req.id;
        resp.error = 0;
        resp.val = USER_NOTIF_MAGIC;

        /* check that we make sure flags == 0 */
        resp.flags = 1;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
        EXPECT_EQ(errno, EINVAL);

        resp.flags = 0;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));
}

TEST(user_notification_with_tsync)
{
        int ret;
        unsigned int flags;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        /* these were exclusive */
        flags = SECCOMP_FILTER_FLAG_NEW_LISTENER |
                SECCOMP_FILTER_FLAG_TSYNC;
        ASSERT_EQ(-1, user_notif_syscall(__NR_getppid, flags));
        ASSERT_EQ(EINVAL, errno);

        /* but now they're not */
        flags |= SECCOMP_FILTER_FLAG_TSYNC_ESRCH;
        ret = user_notif_syscall(__NR_getppid, flags);
        close(ret);
        ASSERT_LE(0, ret);
}

TEST(user_notification_kill_in_middle)
{
        pid_t pid;
        long ret;
        int listener;
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        /*
         * Check that nothing bad happens when we kill the task in the middle
         * of a syscall.
         */
        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                ret = syscall(__NR_getppid);
                exit(ret != USER_NOTIF_MAGIC);
        }

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ID_VALID, &req.id), 0);

        EXPECT_EQ(kill(pid, SIGKILL), 0);
        EXPECT_EQ(waitpid(pid, NULL, 0), pid);

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ID_VALID, &req.id), -1);

        resp.id = req.id;
        ret = ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp);
        EXPECT_EQ(ret, -1);
        EXPECT_EQ(errno, ENOENT);
}

static int handled = -1;

static void signal_handler(int signal)
{
        if (write(handled, "c", 1) != 1)
                perror("write from signal");
}

static void signal_handler_nop(int signal)
{
}

TEST(user_notification_signal)
{
        pid_t pid;
        long ret;
        int status, listener, sk_pair[2];
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};
        char c;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        ASSERT_EQ(socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair), 0);

        listener = user_notif_syscall(__NR_gettid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                close(sk_pair[0]);
                handled = sk_pair[1];
                if (signal(SIGUSR1, signal_handler) == SIG_ERR) {
                        perror("signal");
                        exit(1);
                }
                /*
                 * ERESTARTSYS behavior is a bit hard to test, because we need
                 * to rely on a signal that has not yet been handled. Let's at
                 * least check that the error code gets propagated through, and
                 * hope that it doesn't break when there is actually a signal :)
                 */
                ret = syscall(__NR_gettid);
                exit(!(ret == -1 && errno == 512));
        }

        close(sk_pair[1]);

        memset(&req, 0, sizeof(req));
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);

        EXPECT_EQ(kill(pid, SIGUSR1), 0);

        /*
         * Make sure the signal really is delivered, which means we're not
         * stuck in the user notification code any more and the notification
         * should be dead.
         */
        EXPECT_EQ(read(sk_pair[0], &c, 1), 1);

        resp.id = req.id;
        resp.error = -EPERM;
        resp.val = 0;

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
        EXPECT_EQ(errno, ENOENT);

        memset(&req, 0, sizeof(req));
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);

        resp.id = req.id;
        resp.error = -512; /* -ERESTARTSYS */
        resp.val = 0;

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));
}

TEST(user_notification_closed_listener)
{
        pid_t pid;
        long ret;
        int status, listener;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        /*
         * Check that we get an ENOSYS when the listener is closed.
         */
        pid = fork();
        ASSERT_GE(pid, 0);
        if (pid == 0) {
                close(listener);
                ret = syscall(__NR_getppid);
                exit(ret != -1 && errno != ENOSYS);
        }

        close(listener);

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));
}

/*
 * Check that a pid in a child namespace still shows up as valid in ours.
 */
TEST(user_notification_child_pid_ns)
{
        pid_t pid;
        int status, listener;
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};

        ASSERT_EQ(unshare(CLONE_NEWUSER | CLONE_NEWPID), 0) {
                if (errno == EINVAL)
                        SKIP(return, "kernel missing CLONE_NEWUSER support");
        };

        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0)
                exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
        EXPECT_EQ(req.pid, pid);

        resp.id = req.id;
        resp.error = 0;
        resp.val = USER_NOTIF_MAGIC;

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));
        close(listener);
}

/*
 * Check that a pid in a sibling (i.e. unrelated) namespace shows up as 0, i.e.
 * invalid.
 */
TEST(user_notification_sibling_pid_ns)
{
        pid_t pid, pid2;
        int status, listener;
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};

        ASSERT_EQ(prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0), 0) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                ASSERT_EQ(unshare(CLONE_NEWPID), 0) {
                        if (errno == EPERM)
                                SKIP(return, "CLONE_NEWPID requires CAP_SYS_ADMIN");
                        else if (errno == EINVAL)
                                SKIP(return, "CLONE_NEWPID is invalid (missing CONFIG_PID_NS?)");
                }

                pid2 = fork();
                ASSERT_GE(pid2, 0);

                if (pid2 == 0)
                        exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);

                EXPECT_EQ(waitpid(pid2, &status, 0), pid2);
                EXPECT_EQ(true, WIFEXITED(status));
                EXPECT_EQ(0, WEXITSTATUS(status));
                exit(WEXITSTATUS(status));
        }

        /* Create the sibling ns, and sibling in it. */
        ASSERT_EQ(unshare(CLONE_NEWPID), 0) {
                if (errno == EPERM)
                        SKIP(return, "CLONE_NEWPID requires CAP_SYS_ADMIN");
                else if (errno == EINVAL)
                        SKIP(return, "CLONE_NEWPID is invalid (missing CONFIG_PID_NS?)");
        }
        ASSERT_EQ(errno, 0);

        pid2 = fork();
        ASSERT_GE(pid2, 0);

        if (pid2 == 0) {
                ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
                /*
                 * The pid should be 0, i.e. the task is in some namespace that
                 * we can't "see".
                 */
                EXPECT_EQ(req.pid, 0);

                resp.id = req.id;
                resp.error = 0;
                resp.val = USER_NOTIF_MAGIC;

                ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
                exit(0);
        }

        close(listener);

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));

        EXPECT_EQ(waitpid(pid2, &status, 0), pid2);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));
}

TEST(user_notification_fault_recv)
{
        pid_t pid;
        int status, listener;
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};

        ASSERT_EQ(unshare(CLONE_NEWUSER), 0) {
                if (errno == EINVAL)
                        SKIP(return, "kernel missing CLONE_NEWUSER support");
        }

        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0)
                exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);

        /* Do a bad recv() */
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, NULL), -1);
        EXPECT_EQ(errno, EFAULT);

        /* We should still be able to receive this notification, though. */
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
        EXPECT_EQ(req.pid, pid);

        resp.id = req.id;
        resp.error = 0;
        resp.val = USER_NOTIF_MAGIC;

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));
}

TEST(seccomp_get_notif_sizes)
{
        struct seccomp_notif_sizes sizes;

        ASSERT_EQ(seccomp(SECCOMP_GET_NOTIF_SIZES, 0, &sizes), 0);
        EXPECT_EQ(sizes.seccomp_notif, sizeof(struct seccomp_notif));
        EXPECT_EQ(sizes.seccomp_notif_resp, sizeof(struct seccomp_notif_resp));
}

TEST(user_notification_continue)
{
        pid_t pid;
        long ret;
        int status, listener;
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};
        struct pollfd pollfd;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        listener = user_notif_syscall(__NR_dup, SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                int dup_fd, pipe_fds[2];
                pid_t self;

                ASSERT_GE(pipe(pipe_fds), 0);

                dup_fd = dup(pipe_fds[0]);
                ASSERT_GE(dup_fd, 0);
                EXPECT_NE(pipe_fds[0], dup_fd);

                self = getpid();
                ASSERT_EQ(filecmp(self, self, pipe_fds[0], dup_fd), 0);
                exit(0);
        }

        pollfd.fd = listener;
        pollfd.events = POLLIN | POLLOUT;

        EXPECT_GT(poll(&pollfd, 1, -1), 0);
        EXPECT_EQ(pollfd.revents, POLLIN);

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);

        pollfd.fd = listener;
        pollfd.events = POLLIN | POLLOUT;

        EXPECT_GT(poll(&pollfd, 1, -1), 0);
        EXPECT_EQ(pollfd.revents, POLLOUT);

        EXPECT_EQ(req.data.nr, __NR_dup);

        resp.id = req.id;
        resp.flags = SECCOMP_USER_NOTIF_FLAG_CONTINUE;

        /*
         * Verify that setting SECCOMP_USER_NOTIF_FLAG_CONTINUE enforces other
         * args be set to 0.
         */
        resp.error = 0;
        resp.val = USER_NOTIF_MAGIC;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
        EXPECT_EQ(errno, EINVAL);

        resp.error = USER_NOTIF_MAGIC;
        resp.val = 0;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
        EXPECT_EQ(errno, EINVAL);

        resp.error = 0;
        resp.val = 0;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0) {
                if (errno == EINVAL)
                        SKIP(goto skip, "Kernel does not support SECCOMP_USER_NOTIF_FLAG_CONTINUE");
        }

skip:
        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status)) {
                if (WEXITSTATUS(status) == 2) {
                        SKIP(return, "Kernel does not support kcmp() syscall");
                        return;
                }
        }
}

TEST(user_notification_filter_empty)
{
        pid_t pid;
        long ret;
        int status;
        struct pollfd pollfd;
        struct __clone_args args = {
                .flags = CLONE_FILES,
                .exit_signal = SIGCHLD,
        };

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        if (__NR_clone3 < 0)
                SKIP(return, "Test not built with clone3 support");

        pid = sys_clone3(&args, sizeof(args));
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                int listener;

                listener = user_notif_syscall(__NR_mknodat, SECCOMP_FILTER_FLAG_NEW_LISTENER);
                if (listener < 0)
                        _exit(EXIT_FAILURE);

                if (dup2(listener, 200) != 200)
                        _exit(EXIT_FAILURE);

                close(listener);

                _exit(EXIT_SUCCESS);
        }

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));

        /*
         * The seccomp filter has become unused so we should be notified once
         * the kernel gets around to cleaning up task struct.
         */
        pollfd.fd = 200;
        pollfd.events = POLLHUP;

        EXPECT_GT(poll(&pollfd, 1, 2000), 0);
        EXPECT_GT((pollfd.revents & POLLHUP) ?: 0, 0);
}

TEST(user_ioctl_notification_filter_empty)
{
        pid_t pid;
        long ret;
        int status, p[2];
        struct __clone_args args = {
                .flags = CLONE_FILES,
                .exit_signal = SIGCHLD,
        };
        struct seccomp_notif req = {};

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        if (__NR_clone3 < 0)
                SKIP(return, "Test not built with clone3 support");

        ASSERT_EQ(0, pipe(p));

        pid = sys_clone3(&args, sizeof(args));
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                int listener;

                listener = user_notif_syscall(__NR_mknodat, SECCOMP_FILTER_FLAG_NEW_LISTENER);
                if (listener < 0)
                        _exit(EXIT_FAILURE);

                if (dup2(listener, 200) != 200)
                        _exit(EXIT_FAILURE);
                close(p[1]);
                close(listener);
                sleep(1);

                _exit(EXIT_SUCCESS);
        }
        if (read(p[0], &status, 1) != 0)
                _exit(EXIT_SUCCESS);
        close(p[0]);
        /*
         * The seccomp filter has become unused so we should be notified once
         * the kernel gets around to cleaning up task struct.
         */
        EXPECT_EQ(ioctl(200, SECCOMP_IOCTL_NOTIF_RECV, &req), -1);
        EXPECT_EQ(errno, ENOENT);

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));
}

static void *do_thread(void *data)
{
        return NULL;
}

TEST(user_notification_filter_empty_threaded)
{
        pid_t pid;
        long ret;
        int status;
        struct pollfd pollfd;
        struct __clone_args args = {
                .flags = CLONE_FILES,
                .exit_signal = SIGCHLD,
        };

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        if (__NR_clone3 < 0)
                SKIP(return, "Test not built with clone3 support");

        pid = sys_clone3(&args, sizeof(args));
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                pid_t pid1, pid2;
                int listener, status;
                pthread_t thread;

                listener = user_notif_syscall(__NR_dup, SECCOMP_FILTER_FLAG_NEW_LISTENER);
                if (listener < 0)
                        _exit(EXIT_FAILURE);

                if (dup2(listener, 200) != 200)
                        _exit(EXIT_FAILURE);

                close(listener);

                pid1 = fork();
                if (pid1 < 0)
                        _exit(EXIT_FAILURE);

                if (pid1 == 0)
                        _exit(EXIT_SUCCESS);

                pid2 = fork();
                if (pid2 < 0)
                        _exit(EXIT_FAILURE);

                if (pid2 == 0)
                        _exit(EXIT_SUCCESS);

                if (pthread_create(&thread, NULL, do_thread, NULL) ||
                    pthread_join(thread, NULL))
                        _exit(EXIT_FAILURE);

                if (pthread_create(&thread, NULL, do_thread, NULL) ||
                    pthread_join(thread, NULL))
                        _exit(EXIT_FAILURE);

                if (waitpid(pid1, &status, 0) != pid1 || !WIFEXITED(status) ||
                    WEXITSTATUS(status))
                        _exit(EXIT_FAILURE);

                if (waitpid(pid2, &status, 0) != pid2 || !WIFEXITED(status) ||
                    WEXITSTATUS(status))
                        _exit(EXIT_FAILURE);

                exit(EXIT_SUCCESS);
        }

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));

        /*
         * The seccomp filter has become unused so we should be notified once
         * the kernel gets around to cleaning up task struct.
         */
        pollfd.fd = 200;
        pollfd.events = POLLHUP;

        EXPECT_GT(poll(&pollfd, 1, 2000), 0);
        EXPECT_GT((pollfd.revents & POLLHUP) ?: 0, 0);
}


int get_next_fd(int prev_fd)
{
        for (int i = prev_fd + 1; i < FD_SETSIZE; ++i) {
                if (fcntl(i, F_GETFD) == -1)
                        return i;
        }
        _exit(EXIT_FAILURE);
}

TEST(user_notification_addfd)
{
        pid_t pid;
        long ret;
        int status, listener, memfd, fd, nextfd;
        struct seccomp_notif_addfd addfd = {};
        struct seccomp_notif_addfd_small small = {};
        struct seccomp_notif_addfd_big big = {};
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};
        /* 100 ms */
        struct timespec delay = { .tv_nsec = 100000000 };

        /* There may be arbitrary already-open fds at test start. */
        memfd = memfd_create("test", 0);
        ASSERT_GE(memfd, 0);
        nextfd = get_next_fd(memfd);

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        /* fd: 4 */
        /* Check that the basic notification machinery works */
        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_EQ(listener, nextfd);
        nextfd = get_next_fd(nextfd);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                /* fds will be added and this value is expected */
                if (syscall(__NR_getppid) != USER_NOTIF_MAGIC)
                        exit(1);

                /* Atomic addfd+send is received here. Check it is a valid fd */
                if (fcntl(syscall(__NR_getppid), F_GETFD) == -1)
                        exit(1);

                exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
        }

        ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);

        addfd.srcfd = memfd;
        addfd.newfd = 0;
        addfd.id = req.id;
        addfd.flags = 0x0;

        /* Verify bad newfd_flags cannot be set */
        addfd.newfd_flags = ~O_CLOEXEC;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
        EXPECT_EQ(errno, EINVAL);
        addfd.newfd_flags = O_CLOEXEC;

        /* Verify bad flags cannot be set */
        addfd.flags = 0xff;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
        EXPECT_EQ(errno, EINVAL);
        addfd.flags = 0;

        /* Verify that remote_fd cannot be set without setting flags */
        addfd.newfd = 1;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
        EXPECT_EQ(errno, EINVAL);
        addfd.newfd = 0;

        /* Verify small size cannot be set */
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD_SMALL, &small), -1);
        EXPECT_EQ(errno, EINVAL);

        /* Verify we can't send bits filled in unknown buffer area */
        memset(&big, 0xAA, sizeof(big));
        big.addfd = addfd;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD_BIG, &big), -1);
        EXPECT_EQ(errno, E2BIG);


        /* Verify we can set an arbitrary remote fd */
        fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd);
        EXPECT_EQ(fd, nextfd);
        nextfd = get_next_fd(nextfd);
        EXPECT_EQ(filecmp(getpid(), pid, memfd, fd), 0);

        /* Verify we can set an arbitrary remote fd with large size */
        memset(&big, 0x0, sizeof(big));
        big.addfd = addfd;
        fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD_BIG, &big);
        EXPECT_EQ(fd, nextfd);
        nextfd = get_next_fd(nextfd);

        /* Verify we can set a specific remote fd */
        addfd.newfd = 42;
        addfd.flags = SECCOMP_ADDFD_FLAG_SETFD;
        fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd);
        EXPECT_EQ(fd, 42);
        EXPECT_EQ(filecmp(getpid(), pid, memfd, fd), 0);

        /* Resume syscall */
        resp.id = req.id;
        resp.error = 0;
        resp.val = USER_NOTIF_MAGIC;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        /*
         * This sets the ID of the ADD FD to the last request plus 1. The
         * notification ID increments 1 per notification.
         */
        addfd.id = req.id + 1;

        /* This spins until the underlying notification is generated */
        while (ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd) != -1 &&
               errno != -EINPROGRESS)
                nanosleep(&delay, NULL);

        memset(&req, 0, sizeof(req));
        ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
        ASSERT_EQ(addfd.id, req.id);

        /* Verify we can do an atomic addfd and send */
        addfd.newfd = 0;
        addfd.flags = SECCOMP_ADDFD_FLAG_SEND;
        fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd);
        /*
         * Child has earlier "low" fds and now 42, so we expect the next
         * lowest available fd to be assigned here.
         */
        EXPECT_EQ(fd, nextfd);
        nextfd = get_next_fd(nextfd);
        ASSERT_EQ(filecmp(getpid(), pid, memfd, fd), 0);

        /*
         * This sets the ID of the ADD FD to the last request plus 1. The
         * notification ID increments 1 per notification.
         */
        addfd.id = req.id + 1;

        /* This spins until the underlying notification is generated */
        while (ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd) != -1 &&
               errno != -EINPROGRESS)
                nanosleep(&delay, NULL);

        memset(&req, 0, sizeof(req));
        ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
        ASSERT_EQ(addfd.id, req.id);

        resp.id = req.id;
        resp.error = 0;
        resp.val = USER_NOTIF_MAGIC;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        /* Wait for child to finish. */
        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));

        close(memfd);
}

TEST(user_notification_addfd_rlimit)
{
        pid_t pid;
        long ret;
        int status, listener, memfd;
        struct seccomp_notif_addfd addfd = {};
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};
        const struct rlimit lim = {
                .rlim_cur       = 0,
                .rlim_max       = 0,
        };

        memfd = memfd_create("test", 0);
        ASSERT_GE(memfd, 0);

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        /* Check that the basic notification machinery works */
        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0)
                exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);


        ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);

        ASSERT_EQ(prlimit(pid, RLIMIT_NOFILE, &lim, NULL), 0);

        addfd.srcfd = memfd;
        addfd.newfd_flags = O_CLOEXEC;
        addfd.newfd = 0;
        addfd.id = req.id;
        addfd.flags = 0;

        /* Should probably spot check /proc/sys/fs/file-nr */
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
        EXPECT_EQ(errno, EMFILE);

        addfd.flags = SECCOMP_ADDFD_FLAG_SEND;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
        EXPECT_EQ(errno, EMFILE);

        addfd.newfd = 100;
        addfd.flags = SECCOMP_ADDFD_FLAG_SETFD;
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
        EXPECT_EQ(errno, EBADF);

        resp.id = req.id;
        resp.error = 0;
        resp.val = USER_NOTIF_MAGIC;

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        /* Wait for child to finish. */
        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));

        close(memfd);
}

#ifndef SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP
#define SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP (1UL << 0)
#define SECCOMP_IOCTL_NOTIF_SET_FLAGS  SECCOMP_IOW(4, __u64)
#endif

TEST(user_notification_sync)
{
        struct seccomp_notif req = {};
        struct seccomp_notif_resp resp = {};
        int status, listener;
        pid_t pid;
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        /* Try to set invalid flags. */
        EXPECT_SYSCALL_RETURN(-EINVAL,
                ioctl(listener, SECCOMP_IOCTL_NOTIF_SET_FLAGS, 0xffffffff, 0));

        ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SET_FLAGS,
                        SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP, 0), 0);

        pid = fork();
        ASSERT_GE(pid, 0);
        if (pid == 0) {
                ret = syscall(__NR_getppid);
                ASSERT_EQ(ret, USER_NOTIF_MAGIC) {
                        _exit(1);
                }
                _exit(0);
        }

        req.pid = 0;
        ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);

        ASSERT_EQ(req.data.nr,  __NR_getppid);

        resp.id = req.id;
        resp.error = 0;
        resp.val = USER_NOTIF_MAGIC;
        resp.flags = 0;
        ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        ASSERT_EQ(waitpid(pid, &status, 0), pid);
        ASSERT_EQ(status, 0);
}


/* Make sure PTRACE_O_SUSPEND_SECCOMP requires CAP_SYS_ADMIN. */
FIXTURE(O_SUSPEND_SECCOMP) {
        pid_t pid;
};

FIXTURE_SETUP(O_SUSPEND_SECCOMP)
{
        ERRNO_FILTER(block_read, E2BIG);
        cap_value_t cap_list[] = { CAP_SYS_ADMIN };
        cap_t caps;

        self->pid = 0;

        /* make sure we don't have CAP_SYS_ADMIN */
        caps = cap_get_proc();
        ASSERT_NE(NULL, caps);
        ASSERT_EQ(0, cap_set_flag(caps, CAP_EFFECTIVE, 1, cap_list, CAP_CLEAR));
        ASSERT_EQ(0, cap_set_proc(caps));
        cap_free(caps);

        ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
        ASSERT_EQ(0, prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_block_read));

        self->pid = fork();
        ASSERT_GE(self->pid, 0);

        if (self->pid == 0) {
                while (1)
                        pause();
                _exit(127);
        }
}

FIXTURE_TEARDOWN(O_SUSPEND_SECCOMP)
{
        if (self->pid)
                kill(self->pid, SIGKILL);
}

TEST_F(O_SUSPEND_SECCOMP, setoptions)
{
        int wstatus;

        ASSERT_EQ(0, ptrace(PTRACE_ATTACH, self->pid, NULL, 0));
        ASSERT_EQ(self->pid, wait(&wstatus));
        ASSERT_EQ(-1, ptrace(PTRACE_SETOPTIONS, self->pid, NULL, PTRACE_O_SUSPEND_SECCOMP));
        if (errno == EINVAL)
                SKIP(return, "Kernel does not support PTRACE_O_SUSPEND_SECCOMP (missing CONFIG_CHECKPOINT_RESTORE?)");
        ASSERT_EQ(EPERM, errno);
}

TEST_F(O_SUSPEND_SECCOMP, seize)
{
        int ret;

        ret = ptrace(PTRACE_SEIZE, self->pid, NULL, PTRACE_O_SUSPEND_SECCOMP);
        ASSERT_EQ(-1, ret);
        if (errno == EINVAL)
                SKIP(return, "Kernel does not support PTRACE_O_SUSPEND_SECCOMP (missing CONFIG_CHECKPOINT_RESTORE?)");
        ASSERT_EQ(EPERM, errno);
}

/*
 * get_nth - Get the nth, space separated entry in a file.
 *
 * Returns the length of the read field.
 * Throws error if field is zero-lengthed.
 */
static ssize_t get_nth(struct __test_metadata *_metadata, const char *path,
                     const unsigned int position, char **entry)
{
        char *line = NULL;
        unsigned int i;
        ssize_t nread;
        size_t len = 0;
        FILE *f;

        f = fopen(path, "r");
        ASSERT_NE(f, NULL) {
                TH_LOG("Could not open %s: %s", path, strerror(errno));
        }

        for (i = 0; i < position; i++) {
                nread = getdelim(&line, &len, ' ', f);
                ASSERT_GE(nread, 0) {
                        TH_LOG("Failed to read %d entry in file %s", i, path);
                }
        }
        fclose(f);

        ASSERT_GT(nread, 0) {
                TH_LOG("Entry in file %s had zero length", path);
        }

        *entry = line;
        return nread - 1;
}

/* For a given PID, get the task state (D, R, etc...) */
static char get_proc_stat(struct __test_metadata *_metadata, pid_t pid)
{
        char proc_path[100] = {0};
        char status;
        char *line;

        snprintf(proc_path, sizeof(proc_path), "/proc/%d/stat", pid);
        ASSERT_EQ(get_nth(_metadata, proc_path, 3, &line), 1);

        status = *line;
        free(line);

        return status;
}

TEST(user_notification_fifo)
{
        struct seccomp_notif_resp resp = {};
        struct seccomp_notif req = {};
        int i, status, listener;
        pid_t pid, pids[3];
        __u64 baseid;
        long ret;
        /* 100 ms */
        struct timespec delay = { .tv_nsec = 100000000 };

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        /* Setup a listener */
        listener = user_notif_syscall(__NR_getppid,
                                      SECCOMP_FILTER_FLAG_NEW_LISTENER);
        ASSERT_GE(listener, 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                ret = syscall(__NR_getppid);
                exit(ret != USER_NOTIF_MAGIC);
        }

        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
        baseid = req.id + 1;

        resp.id = req.id;
        resp.error = 0;
        resp.val = USER_NOTIF_MAGIC;

        /* check that we make sure flags == 0 */
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));

        /* Start children, and generate notifications */
        for (i = 0; i < ARRAY_SIZE(pids); i++) {
                pid = fork();
                if (pid == 0) {
                        ret = syscall(__NR_getppid);
                        exit(ret != USER_NOTIF_MAGIC);
                }
                pids[i] = pid;
        }

        /* This spins until all of the children are sleeping */
restart_wait:
        for (i = 0; i < ARRAY_SIZE(pids); i++) {
                if (get_proc_stat(_metadata, pids[i]) != 'S') {
                        nanosleep(&delay, NULL);
                        goto restart_wait;
                }
        }

        /* Read the notifications in order (and respond) */
        for (i = 0; i < ARRAY_SIZE(pids); i++) {
                memset(&req, 0, sizeof(req));
                EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
                EXPECT_EQ(req.id, baseid + i);
                resp.id = req.id;
                EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
        }

        /* Make sure notifications were received */
        for (i = 0; i < ARRAY_SIZE(pids); i++) {
                EXPECT_EQ(waitpid(pids[i], &status, 0), pids[i]);
                EXPECT_EQ(true, WIFEXITED(status));
                EXPECT_EQ(0, WEXITSTATUS(status));
        }
}

/* get_proc_syscall - Get the syscall in progress for a given pid
 *
 * Returns the current syscall number for a given process
 * Returns -1 if not in syscall (running or blocked)
 */
static long get_proc_syscall(struct __test_metadata *_metadata, int pid)
{
        char proc_path[100] = {0};
        long ret = -1;
        ssize_t nread;
        char *line;

        snprintf(proc_path, sizeof(proc_path), "/proc/%d/syscall", pid);
        nread = get_nth(_metadata, proc_path, 1, &line);
        ASSERT_GT(nread, 0);

        if (!strncmp("running", line, MIN(7, nread)))
                ret = strtol(line, NULL, 16);

        free(line);
        return ret;
}

/* Ensure non-fatal signals prior to receive are unmodified */
TEST(user_notification_wait_killable_pre_notification)
{
        struct sigaction new_action = {
                .sa_handler = signal_handler,
        };
        int listener, status, sk_pair[2];
        pid_t pid;
        long ret;
        char c;
        /* 100 ms */
        struct timespec delay = { .tv_nsec = 100000000 };

        ASSERT_EQ(sigemptyset(&new_action.sa_mask), 0);

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret)
        {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        ASSERT_EQ(socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair), 0);

        listener = user_notif_syscall(
                __NR_getppid, SECCOMP_FILTER_FLAG_NEW_LISTENER |
                                      SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV);
        ASSERT_GE(listener, 0);

        /*
         * Check that we can kill the process with SIGUSR1 prior to receiving
         * the notification. SIGUSR1 is wired up to a custom signal handler,
         * and make sure it gets called.
         */
        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                close(sk_pair[0]);
                handled = sk_pair[1];

                /* Setup the non-fatal sigaction without SA_RESTART */
                if (sigaction(SIGUSR1, &new_action, NULL)) {
                        perror("sigaction");
                        exit(1);
                }

                ret = syscall(__NR_getppid);
                /* Make sure we got a return from a signal interruption */
                exit(ret != -1 || errno != EINTR);
        }

        /*
         * Make sure we've gotten to the seccomp user notification wait
         * from getppid prior to sending any signals
         */
        while (get_proc_syscall(_metadata, pid) != __NR_getppid &&
               get_proc_stat(_metadata, pid) != 'S')
                nanosleep(&delay, NULL);

        /* Send non-fatal kill signal */
        EXPECT_EQ(kill(pid, SIGUSR1), 0);

        /* wait for process to exit (exit checks for EINTR) */
        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));

        EXPECT_EQ(read(sk_pair[0], &c, 1), 1);
}

/* Ensure non-fatal signals after receive are blocked */
TEST(user_notification_wait_killable)
{
        struct sigaction new_action = {
                .sa_handler = signal_handler,
        };
        struct seccomp_notif_resp resp = {};
        struct seccomp_notif req = {};
        int listener, status, sk_pair[2];
        pid_t pid;
        long ret;
        char c;
        /* 100 ms */
        struct timespec delay = { .tv_nsec = 100000000 };

        ASSERT_EQ(sigemptyset(&new_action.sa_mask), 0);

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret)
        {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        ASSERT_EQ(socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair), 0);

        listener = user_notif_syscall(
                __NR_getppid, SECCOMP_FILTER_FLAG_NEW_LISTENER |
                                      SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV);
        ASSERT_GE(listener, 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                close(sk_pair[0]);
                handled = sk_pair[1];

                /* Setup the sigaction without SA_RESTART */
                if (sigaction(SIGUSR1, &new_action, NULL)) {
                        perror("sigaction");
                        exit(1);
                }

                /* Make sure that the syscall is completed (no EINTR) */
                ret = syscall(__NR_getppid);
                exit(ret != USER_NOTIF_MAGIC);
        }

        /*
         * Get the notification, to make move the notifying process into a
         * non-preemptible (TASK_KILLABLE) state.
         */
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
        /* Send non-fatal kill signal */
        EXPECT_EQ(kill(pid, SIGUSR1), 0);

        /*
         * Make sure the task enters moves to TASK_KILLABLE by waiting for
         * D (Disk Sleep) state after receiving non-fatal signal.
         */
        while (get_proc_stat(_metadata, pid) != 'D')
                nanosleep(&delay, NULL);

        resp.id = req.id;
        resp.val = USER_NOTIF_MAGIC;
        /* Make sure the notification is found and able to be replied to */
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);

        /*
         * Make sure that the signal handler does get called once we're back in
         * userspace.
         */
        EXPECT_EQ(read(sk_pair[0], &c, 1), 1);
        /* wait for process to exit (exit checks for USER_NOTIF_MAGIC) */
        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));
}

/* Ensure fatal signals after receive are not blocked */
TEST(user_notification_wait_killable_fatal)
{
        struct seccomp_notif req = {};
        int listener, status;
        pid_t pid;
        long ret;
        /* 100 ms */
        struct timespec delay = { .tv_nsec = 100000000 };

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret)
        {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        listener = user_notif_syscall(
                __NR_getppid, SECCOMP_FILTER_FLAG_NEW_LISTENER |
                                      SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV);
        ASSERT_GE(listener, 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                /* This should never complete as it should get a SIGTERM */
                syscall(__NR_getppid);
                exit(1);
        }

        while (get_proc_stat(_metadata, pid) != 'S')
                nanosleep(&delay, NULL);

        /*
         * Get the notification, to make move the notifying process into a
         * non-preemptible (TASK_KILLABLE) state.
         */
        EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
        /* Kill the process with a fatal signal */
        EXPECT_EQ(kill(pid, SIGTERM), 0);

        /*
         * Wait for the process to exit, and make sure the process terminated
         * due to the SIGTERM signal.
         */
        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFSIGNALED(status));
        EXPECT_EQ(SIGTERM, WTERMSIG(status));
}

/* Ensure signals after the reply do not interrupt */
TEST(user_notification_wait_killable_after_reply)
{
        int i, max_iter = 100000;
        int listener, status;
        int pipe_fds[2];
        pid_t pid;
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret)
        {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        listener = user_notif_syscall(
                __NR_dup, SECCOMP_FILTER_FLAG_NEW_LISTENER |
                          SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV);
        ASSERT_GE(listener, 0);

        /*
         * Used to count invocations. One token is transferred from the child
         * to the parent per syscall invocation, the parent tries to take
         * one token per successful RECV. If the syscall is restarted after
         * RECV the parent will try to get two tokens while the child only
         * provided one.
         */
        ASSERT_EQ(pipe(pipe_fds), 0);

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                struct sigaction new_action = {
                        .sa_handler = signal_handler_nop,
                        .sa_flags = SA_RESTART,
                };
                struct itimerval timer = {
                        .it_value = { .tv_usec = 1000 },
                        .it_interval = { .tv_usec = 1000 },
                };
                char c = 'a';

                close(pipe_fds[0]);

                /* Setup the sigaction with SA_RESTART */
                if (sigaction(SIGALRM, &new_action, NULL)) {
                        perror("sigaction");
                        exit(1);
                }

                /*
                 * Kill with SIGALRM repeatedly, to try to hit the race when
                 * handling the syscall.
                 */
                if (setitimer(ITIMER_REAL, &timer, NULL) < 0)
                        perror("setitimer");

                for (i = 0; i < max_iter; ++i) {
                        int fd;

                        /* Send one token per iteration to catch repeats. */
                        if (write(pipe_fds[1], &c, sizeof(c)) != 1) {
                                perror("write");
                                exit(1);
                        }

                        fd = syscall(__NR_dup, 0);
                        if (fd < 0) {
                                perror("dup");
                                exit(1);
                        }
                        close(fd);
                }

                exit(0);
        }

        close(pipe_fds[1]);

        for (i = 0; i < max_iter; ++i) {
                struct seccomp_notif req = {};
                struct seccomp_notif_addfd addfd = {};
                struct pollfd pfd = {
                        .fd = pipe_fds[0],
                        .events = POLLIN,
                };
                char c;

                /*
                 * Try to receive one token. If it failed, one child syscall
                 * was restarted after RECV and needed to be handled twice.
                 */
                ASSERT_EQ(poll(&pfd, 1, 1000), 1)
                        kill(pid, SIGKILL);

                ASSERT_EQ(read(pipe_fds[0], &c, sizeof(c)), 1)
                        kill(pid, SIGKILL);

                /*
                 * Get the notification, reply to it as fast as possible to test
                 * whether the child wrongly skips going into the non-preemptible
                 * (TASK_KILLABLE) state.
                 */
                do
                        ret = ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req);
                while (ret < 0 && errno == ENOENT); /* Accept interruptions before RECV */
                ASSERT_EQ(ret, 0)
                        kill(pid, SIGKILL);

                addfd.id = req.id;
                addfd.flags = SECCOMP_ADDFD_FLAG_SEND;
                addfd.srcfd = 0;
                ASSERT_GE(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), 0)
                        kill(pid, SIGKILL);
        }

        /*
         * Wait for the process to exit, and make sure the process terminated
         * with a zero exit code..
         */
        EXPECT_EQ(waitpid(pid, &status, 0), pid);
        EXPECT_EQ(true, WIFEXITED(status));
        EXPECT_EQ(0, WEXITSTATUS(status));
}

struct tsync_vs_thread_leader_args {
        pthread_t leader;
};

static void *tsync_vs_dead_thread_leader_sibling(void *_args)
{
        struct sock_filter allow_filter[] = {
                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 tsync_vs_thread_leader_args *args = _args;
        void *retval;
        long ret;

        ret = pthread_join(args->leader, &retval);
        if (ret)
                exit(1);
        if (retval != _args)
                exit(2);
        ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC, &allow_prog);
        if (ret)
                exit(3);

        exit(0);
}

/*
 * Ensure that a dead thread leader doesn't prevent installing new filters with
 * SECCOMP_FILTER_FLAG_TSYNC from other threads.
 */
TEST(tsync_vs_dead_thread_leader)
{
        int status;
        pid_t pid;
        long ret;

        ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
        ASSERT_EQ(0, ret) {
                TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
        }

        pid = fork();
        ASSERT_GE(pid, 0);

        if (pid == 0) {
                struct sock_filter allow_filter[] = {
                        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  tsync_vs_thread_leader_args *args;
                pthread_t sibling;

                args = malloc(sizeof(*args));
                ASSERT_NE(NULL, args);
                args->leader = pthread_self();

                ret = pthread_create(&sibling, NULL,
                                     tsync_vs_dead_thread_leader_sibling, args);
                ASSERT_EQ(0, ret);

                /* Install a new filter just to the leader thread. */
                ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
                ASSERT_EQ(0, ret);
                pthread_exit(args);
                exit(1);
        }

        EXPECT_EQ(pid, waitpid(pid, &status, 0));
        EXPECT_EQ(0, status);
}

#ifdef __x86_64__

/*
 * We need naked probed_uprobe function. Using __nocf_check
 * check to skip possible endbr64 instruction and ignoring
 * -Wattributes, otherwise the compilation might fail.
 */
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wattributes"

__naked __nocf_check noinline int probed_uprobe(void)
{
        /*
         * Optimized uprobe is possible only on top of nop5 instruction.
         */
        asm volatile ("                                 \n"
                ".byte 0x0f, 0x1f, 0x44, 0x00, 0x00     \n"
                "ret                                    \n"
        );
}
#pragma GCC diagnostic pop

#else
noinline int probed_uprobe(void)
{
        return 1;
}
#endif

noinline int probed_uretprobe(void)
{
        return 1;
}

static int parse_uint_from_file(const char *file, const char *fmt)
{
        int err = -1, ret;
        FILE *f;

        f = fopen(file, "re");
        if (f) {
                err = fscanf(f, fmt, &ret);
                fclose(f);
        }
        return err == 1 ? ret : err;
}

static int determine_uprobe_perf_type(void)
{
        const char *file = "/sys/bus/event_source/devices/uprobe/type";

        return parse_uint_from_file(file, "%d\n");
}

static int determine_uprobe_retprobe_bit(void)
{
        const char *file = "/sys/bus/event_source/devices/uprobe/format/retprobe";

        return parse_uint_from_file(file, "config:%d\n");
}

static ssize_t get_uprobe_offset(const void *addr)
{
        size_t start, base, end;
        bool found = false;
        char buf[256];
        FILE *f;

        f = fopen("/proc/self/maps", "r");
        if (!f)
                return -1;

        while (fscanf(f, "%zx-%zx %s %zx %*[^\n]\n", &start, &end, buf, &base) == 4) {
                if (buf[2] == 'x' && (uintptr_t)addr >= start && (uintptr_t)addr < end) {
                        found = true;
                        break;
                }
        }
        fclose(f);
        return found ? (uintptr_t)addr - start + base : -1;
}

FIXTURE(UPROBE) {
        int fd;
};

FIXTURE_VARIANT(UPROBE) {
        /*
         * All of the U(RET)PROBE behaviors can be tested with either
         * u(ret)probe attached or not
         */
        bool attach;
        /*
         * Test both uprobe and uretprobe.
         */
        bool uretprobe;
};

FIXTURE_VARIANT_ADD(UPROBE, not_attached) {
        .attach = false,
        .uretprobe = false,
};

FIXTURE_VARIANT_ADD(UPROBE, uprobe_attached) {
        .attach = true,
        .uretprobe = false,
};

FIXTURE_VARIANT_ADD(UPROBE, uretprobe_attached) {
        .attach = true,
        .uretprobe = true,
};

FIXTURE_SETUP(UPROBE)
{
        const size_t attr_sz = sizeof(struct perf_event_attr);
        struct perf_event_attr attr;
        ssize_t offset;
        int type, bit;

#if !defined(__NR_uprobe) || !defined(__NR_uretprobe)
        SKIP(return, "__NR_uprobe ot __NR_uretprobe syscalls not defined");
#endif

        if (!variant->attach)
                return;

        memset(&attr, 0, attr_sz);

        type = determine_uprobe_perf_type();
        ASSERT_GE(type, 0);

        if (variant->uretprobe) {
                bit = determine_uprobe_retprobe_bit();
                ASSERT_GE(bit, 0);
        }

        offset = get_uprobe_offset(variant->uretprobe ? probed_uretprobe : probed_uprobe);
        ASSERT_GE(offset, 0);

        if (variant->uretprobe)
                attr.config |= 1 << bit;
        attr.size = attr_sz;
        attr.type = type;
        attr.config1 = ptr_to_u64("/proc/self/exe");
        attr.config2 = offset;

        self->fd = syscall(__NR_perf_event_open, &attr,
                           getpid() /* pid */, -1 /* cpu */, -1 /* group_fd */,
                           PERF_FLAG_FD_CLOEXEC);
}

FIXTURE_TEARDOWN(UPROBE)
{
        /* we could call close(self->fd), but we'd need extra filter for
         * that and since we are calling _exit right away..
         */
}

static int run_probed_with_filter(struct sock_fprog *prog)
{
        if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) ||
            seccomp(SECCOMP_SET_MODE_FILTER, 0, prog)) {
                return -1;
        }

        /*
         * Uprobe is optimized after first hit, so let's hit twice.
         */
        probed_uprobe();
        probed_uprobe();

        probed_uretprobe();
        return 0;
}

TEST_F(UPROBE, uprobe_default_allow)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };

        ASSERT_EQ(0, run_probed_with_filter(&prog));
}

TEST_F(UPROBE, uprobe_default_block)
{
        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_exit_group, 1, 0),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };

        ASSERT_EQ(0, run_probed_with_filter(&prog));
}

TEST_F(UPROBE, uprobe_block_syscall)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
                        offsetof(struct seccomp_data, nr)),
#ifdef __NR_uprobe
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_uprobe, 1, 2),
#endif
#ifdef __NR_uretprobe
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_uretprobe, 0, 1),
#endif
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };

        ASSERT_EQ(0, run_probed_with_filter(&prog));
}

TEST_F(UPROBE, uprobe_default_block_with_syscall)
{
        struct sock_filter filter[] = {
                BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
                        offsetof(struct seccomp_data, nr)),
#ifdef __NR_uprobe
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_uprobe, 3, 0),
#endif
#ifdef __NR_uretprobe
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_uretprobe, 2, 0),
#endif
                BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit_group, 1, 0),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
                BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
        };
        struct sock_fprog prog = {
                .len = (unsigned short)ARRAY_SIZE(filter),
                .filter = filter,
        };

        ASSERT_EQ(0, run_probed_with_filter(&prog));
}

/*
 * TODO:
 * - expand NNP testing
 * - better arch-specific TRACE and TRAP handlers.
 * - 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
 */

TEST_HARNESS_MAIN