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4ee0776760
linux_dsm_epyc7002/tools/testing/selftests/seccomp/seccomp_bpf.c
Kees Cook 4ee0776760 selftests/seccomp: Prepare for exclusive seccomp flags 
Some seccomp flags will become exclusive, so the selftest needs to
be adjusted to mask those out and test them individually for the "all
flags" tests.

Cc: stable@vger.kernel.org # v5.0+
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Tycho Andersen <tycho@tycho.ws>
Acked-by: James Morris <jamorris@linux.microsoft.com>
2019-04-25 15:55:48 -07:00

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/*
* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by the GPLv2 license.
*
* 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/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 <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 <unistd.h>
#include <sys/syscall.h>
#include <poll.h>
#include "../kselftest_harness.h"
#ifndef PR_SET_PTRACER
# define PR_SET_PTRACER 0x59616d61
#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(__hppa__)
# define __NR_seccomp 338
# elif defined(__powerpc__)
# define __NR_seccomp 358
# elif defined(__s390__)
# define __NR_seccomp 348
# else
# warning "seccomp syscall number unknown for this architecture"
# define __NR_seccomp 0xffff
# endif
#endif
#ifndef SECCOMP_SET_MODE_STRICT
#define SECCOMP_SET_MODE_STRICT 0
#endif
#ifndef SECCOMP_SET_MODE_FILTER
#define SECCOMP_SET_MODE_FILTER 1
#endif
#ifndef SECCOMP_GET_ACTION_AVAIL
#define SECCOMP_GET_ACTION_AVAIL 2
#endif
#ifndef SECCOMP_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)
#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_IOR(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
int seccomp(unsigned int op, unsigned int flags, void *args)
{
errno = 0;
return syscall(__NR_seccomp, op, flags, args);
}
#endif
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
#elif __BYTE_ORDER == __BIG_ENDIAN
#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
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;
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 */
/* TODO(wad) check caps not euid */
if (geteuid()) {
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) {
prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
return (void *)SIBLING_EXIT_FAILURE;
}
return (void *)SIBLING_EXIT_UNKILLED;
}
/* Prepare a thread that will kill itself or both of us. */
void kill_thread_or_group(struct __test_metadata *_metadata, bool kill_process)
{
pthread_t thread;
void *status;
/* Kill only when calling __NR_prctl. */
struct sock_filter filter_thread[] = {
BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
offsetof(struct seccomp_data, nr)),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_THREAD),
BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
};
struct sock_fprog prog_thread = {
.len = (unsigned short)ARRAY_SIZE(filter_thread),
.filter = filter_thread,
};
struct sock_filter filter_process[] = {
BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
offsetof(struct seccomp_data, nr)),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_PROCESS),
BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
};
struct sock_fprog prog_process = {
.len = (unsigned short)ARRAY_SIZE(filter_process),
.filter = filter_process,
};
ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
}
ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0,
kill_process ? &prog_process : &prog_thread));
/*
* Add the KILL_THREAD rule again to make sure that the KILL_PROCESS
* flag cannot be downgraded by a new filter.
*/
ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog_thread));
/* Start a thread that will exit immediately. */
ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)false));
ASSERT_EQ(0, pthread_join(thread, &status));
ASSERT_EQ(SIBLING_EXIT_UNKILLED, (unsigned long)status);
/* Start a thread that will die immediately. */
ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)true));
ASSERT_EQ(0, pthread_join(thread, &status));
ASSERT_NE(SIBLING_EXIT_FAILURE, (unsigned long)status);
/*
* If we get here, only the spawned thread died. Let the parent know
* the whole process didn't die (i.e. this thread, the spawner,
* stayed running).
*/
exit(42);
}
TEST(KILL_thread)
{
int status;
pid_t child_pid;
child_pid = fork();
ASSERT_LE(0, child_pid);
if (child_pid == 0) {
kill_thread_or_group(_metadata, false);
_exit(38);
}
ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
/* If only the thread was killed, we'll see exit 42. */
ASSERT_TRUE(WIFEXITED(status));
ASSERT_EQ(42, WEXITSTATUS(status));
}
TEST(KILL_process)
{
int status;
pid_t child_pid;
child_pid = fork();
ASSERT_LE(0, child_pid);
if (child_pid == 0) {
kill_thread_or_group(_metadata, true);
_exit(38);
}
ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
/* If the entire process was killed, we'll see SIGSYS. */
ASSERT_TRUE(WIFSIGNALED(status));
ASSERT_EQ(SIGSYS, WTERMSIG(status));
}
/* TODO(wad) add 64-bit versus 32-bit arg tests. */
TEST(arg_out_of_range)
{
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(0, 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(0, NULL, 0));
}
/*
* The SECCOMP_RET_DATA mask is 16 bits wide, but errno is smaller.
* This tests that the errno value gets capped correctly, fixed by
* 580c57f10768 ("seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO").
*/
TEST(ERRNO_capped)
{
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(0, 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(0, NULL, 0));
EXPECT_EQ(12, errno);
}
FIXTURE_DATA(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_DATA(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 IS_SECCOMP_EVENT(status) ((status >> 16) == PTRACE_EVENT_SECCOMP)
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) || WIFEXITED(status))
/* Child is dead. Time to go. */
return;
/* Check if this is a seccomp event. */
ASSERT_EQ(!ptrace_syscall, IS_SECCOMP_EVENT(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->passed ? EXIT_SUCCESS : EXIT_FAILURE);
}
/* 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;
/*
* Extract the exit code from the other process and
* adopt it for ourselves in case its asserts failed.
*/
ASSERT_EQ(0, kill(tracer, SIGUSR1));
ASSERT_EQ(tracer, waitpid(tracer, &status, 0));
if (WEXITSTATUS(status))
_metadata->passed = 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_DATA(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 orig_rax
# define SYSCALL_RET rax
#elif defined(__i386__)
# define ARCH_REGS struct user_regs_struct
# define SYSCALL_NUM orig_eax
# define SYSCALL_RET eax
#elif defined(__arm__)
# define ARCH_REGS struct pt_regs
# define SYSCALL_NUM ARM_r7
# define SYSCALL_RET ARM_r0
#elif defined(__aarch64__)
# define ARCH_REGS struct user_pt_regs
# define SYSCALL_NUM regs[8]
# define SYSCALL_RET regs[0]
#elif defined(__hppa__)
# define ARCH_REGS struct user_regs_struct
# define SYSCALL_NUM gr[20]
# define SYSCALL_RET gr[28]
#elif defined(__powerpc__)
# define ARCH_REGS struct pt_regs
# define SYSCALL_NUM gpr[0]
# define SYSCALL_RET gpr[3]
#elif defined(__s390__)
# define ARCH_REGS s390_regs
# define SYSCALL_NUM gprs[2]
# define SYSCALL_RET gprs[2]
#elif defined(__mips__)
# define ARCH_REGS struct pt_regs
# define SYSCALL_NUM regs[2]
# define SYSCALL_SYSCALL_NUM regs[4]
# define SYSCALL_RET regs[2]
# define SYSCALL_NUM_RET_SHARE_REG
#else
# error "Do not know how to find your architecture's registers and syscalls"
#endif
/* When the syscall return can't be changed, stub out the tests for it. */
#ifdef SYSCALL_NUM_RET_SHARE_REG
# define EXPECT_SYSCALL_RETURN(val, action) EXPECT_EQ(-1, action)
#else
# define EXPECT_SYSCALL_RETURN(val, action) \
do { \
errno = 0; \
if (val < 0) { \
EXPECT_EQ(-1, action); \
EXPECT_EQ(-(val), errno); \
} else { \
EXPECT_EQ(val, action); \
} \
} while (0)
#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__)
#define HAVE_GETREGS
#endif
/* Architecture-specific syscall fetching routine. */
int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
{
ARCH_REGS regs;
#ifdef HAVE_GETREGS
EXPECT_EQ(0, ptrace(PTRACE_GETREGS, tracee, 0, &regs)) {
TH_LOG("PTRACE_GETREGS failed");
return -1;
}
#else
struct iovec iov;
iov.iov_base = &regs;
iov.iov_len = sizeof(regs);
EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) {
TH_LOG("PTRACE_GETREGSET failed");
return -1;
}
#endif
#if defined(__mips__)
if (regs.SYSCALL_NUM == __NR_O32_Linux)
return regs.SYSCALL_SYSCALL_NUM;
#endif
return regs.SYSCALL_NUM;
}
/* Architecture-specific syscall changing routine. */
void change_syscall(struct __test_metadata *_metadata,
pid_t tracee, int syscall, int result)
{
int ret;
ARCH_REGS regs;
#ifdef HAVE_GETREGS
ret = ptrace(PTRACE_GETREGS, tracee, 0, &regs);
#else
struct iovec iov;
iov.iov_base = &regs;
iov.iov_len = sizeof(regs);
ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov);
#endif
EXPECT_EQ(0, ret) {}
#if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \
defined(__s390__) || defined(__hppa__)
{
regs.SYSCALL_NUM = syscall;
}
#elif defined(__mips__)
{
if (regs.SYSCALL_NUM == __NR_O32_Linux)
regs.SYSCALL_SYSCALL_NUM = syscall;
else
regs.SYSCALL_NUM = syscall;
}
#elif defined(__arm__)
# ifndef PTRACE_SET_SYSCALL
# define PTRACE_SET_SYSCALL 23
# endif
{
ret = ptrace(PTRACE_SET_SYSCALL, tracee, NULL, syscall);
EXPECT_EQ(0, ret);
}
#elif defined(__aarch64__)
# ifndef NT_ARM_SYSTEM_CALL
# define NT_ARM_SYSTEM_CALL 0x404
# endif
{
iov.iov_base = &syscall;
iov.iov_len = sizeof(syscall);
ret = ptrace(PTRACE_SETREGSET, tracee, NT_ARM_SYSTEM_CALL,
&iov);
EXPECT_EQ(0, ret);
}
#else
ASSERT_EQ(1, 0) {
TH_LOG("How is the syscall changed on this architecture?");
}
#endif
/* If syscall is skipped, change return value. */
if (syscall == -1)
#ifdef SYSCALL_NUM_RET_SHARE_REG
TH_LOG("Can't modify syscall return on this architecture");
#else
regs.SYSCALL_RET = result;
#endif
#ifdef HAVE_GETREGS
ret = ptrace(PTRACE_SETREGS, tracee, 0, &regs);
#else
iov.iov_base = &regs;
iov.iov_len = sizeof(regs);
ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov);
#endif
EXPECT_EQ(0, ret);
}
void tracer_syscall(struct __test_metadata *_metadata, pid_t tracee,
int status, void *args)
{
int ret;
unsigned long msg;
/* 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(_metadata, tracee, __NR_getppid, 0);
break;
case 0x1003:
/* skip gettid with valid return code. */
EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
change_syscall(_metadata, tracee, -1, 45000);
break;
case 0x1004:
/* skip openat with error. */
EXPECT_EQ(__NR_openat, get_syscall(_metadata, tracee));
change_syscall(_metadata, tracee, -1, -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);
}
}
}
void tracer_ptrace(struct __test_metadata *_metadata, pid_t tracee,
int status, void *args)
{
int ret, nr;
unsigned long msg;
static bool entry;
/* Make sure we got an empty message. */
ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
EXPECT_EQ(0, ret);
EXPECT_EQ(0, msg);
/* The only way to tell PTRACE_SYSCALL entry/exit is by counting. */
entry = !entry;
if (!entry)
return;
nr = get_syscall(_metadata, tracee);
if (nr == __NR_getpid)
change_syscall(_metadata, tracee, __NR_getppid, 0);
if (nr == __NR_gettid)
change_syscall(_metadata, tracee, -1, 45000);
if (nr == __NR_openat)
change_syscall(_metadata, tracee, -1, -ESRCH);
}
FIXTURE_DATA(TRACE_syscall) {
struct sock_fprog prog;
pid_t tracer, mytid, mypid, parent;
};
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),
};
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);
/* 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, tracer_syscall, NULL,
false);
}
FIXTURE_TEARDOWN(TRACE_syscall)
{
teardown_trace_fixture(_metadata, self->tracer);
if (self->prog.filter)
free(self->prog.filter);
}
TEST_F(TRACE_syscall, ptrace_syscall_redirected)
{
/* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
teardown_trace_fixture(_metadata, self->tracer);
self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
true);
/* Tracer will redirect getpid to getppid. */
EXPECT_NE(self->mypid, syscall(__NR_getpid));
}
TEST_F(TRACE_syscall, ptrace_syscall_errno)
{
/* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
teardown_trace_fixture(_metadata, self->tracer);
self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
true);
/* Tracer should skip the open syscall, resulting in ESRCH. */
EXPECT_SYSCALL_RETURN(-ESRCH, syscall(__NR_openat));
}
TEST_F(TRACE_syscall, ptrace_syscall_faked)
{
/* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
teardown_trace_fixture(_metadata, self->tracer);
self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
true);
/* Tracer should skip the gettid syscall, resulting fake pid. */
EXPECT_SYSCALL_RETURN(45000, syscall(__NR_gettid));
}
TEST_F(TRACE_syscall, syscall_allowed)
{
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);
/* 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)
{
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);
/* 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)
{
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);
/* openat has been skipped and an errno return. */
EXPECT_SYSCALL_RETURN(-ESRCH, syscall(__NR_openat));
}
TEST_F(TRACE_syscall, syscall_faked)
{
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);
/* gettid has been skipped and an altered return value stored. */
EXPECT_SYSCALL_RETURN(45000, syscall(__NR_gettid));
}
TEST_F(TRACE_syscall, skip_after_RET_TRACE)
{
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;
ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
ASSERT_EQ(0, ret);
/* Install fixture filter. */
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
ASSERT_EQ(0, ret);
/* Install "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_RET_TRACE, 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;
ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
ASSERT_EQ(0, ret);
/* Install fixture filter. */
ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
ASSERT_EQ(0, ret);
/* Install "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_F(TRACE_syscall, skip_after_ptrace)
{
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;
/* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
teardown_trace_fixture(_metadata, self->tracer);
self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
true);
ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
ASSERT_EQ(0, ret);
/* Install "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. */
EXPECT_EQ(-1, syscall(__NR_getpid));
EXPECT_EQ(EPERM, errno);
}
TEST_F_SIGNAL(TRACE_syscall, kill_after_ptrace, 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;
/* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
teardown_trace_fixture(_metadata, self->tracer);
self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
true);
ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
ASSERT_EQ(0, ret);
/* Install "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 };
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_DATA(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(0, 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_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, 6, 0),
#endif
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 5, 0),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 4, 0),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 3, 0),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_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)", 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->passed ? EXIT_SUCCESS
: EXIT_FAILURE);
}
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);
EXPECT_EQ(__NR_nanosleep, get_syscall(_metadata, child_pid));
/* 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__)
/*
* FIXME:
* - native ARM registers do NOT expose true syscall.
* - compat ARM registers on ARM64 DO expose true syscall.
*/
ASSERT_EQ(0, uname(&utsbuf));
if (strncmp(utsbuf.machine, "arm", 3) == 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->passed = 0;
}
TEST_SIGNAL(filter_flag_log, SIGSYS)
{
struct sock_filter allow_filter[] = {
BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
};
struct sock_filter kill_filter[] = {
BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
offsetof(struct seccomp_data, nr)),
BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
};
struct sock_fprog allow_prog = {
.len = (unsigned short)ARRAY_SIZE(allow_filter),
.filter = allow_filter,
};
struct sock_fprog kill_prog = {
.len = (unsigned short)ARRAY_SIZE(kill_filter),
.filter = kill_filter,
};
long ret;
pid_t parent = getppid();
ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
ASSERT_EQ(0, ret);
/* Verify that the FILTER_FLAG_LOG flag isn't accepted in strict mode */
ret = seccomp(SECCOMP_SET_MODE_STRICT, SECCOMP_FILTER_FLAG_LOG,
&allow_prog);
ASSERT_NE(ENOSYS, errno) {
TH_LOG("Kernel does not support seccomp syscall!");
}
EXPECT_NE(0, ret) {
TH_LOG("Kernel accepted FILTER_FLAG_LOG flag in strict mode!");
}
EXPECT_EQ(EINVAL, errno) {
TH_LOG("Kernel returned unexpected errno for FILTER_FLAG_LOG flag in strict mode!");
}
/* Verify that a simple, permissive filter can be added with no flags */
ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
EXPECT_EQ(0, ret);
/* See if the same filter can be added with the FILTER_FLAG_LOG flag */
ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
&allow_prog);
ASSERT_NE(EINVAL, errno) {
TH_LOG("Kernel does not support the FILTER_FLAG_LOG flag!");
}
EXPECT_EQ(0, ret);
/* Ensure that the kill filter works with the FILTER_FLAG_LOG flag */
ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
&kill_prog);
EXPECT_EQ(0, ret);
EXPECT_EQ(parent, syscall(__NR_getppid));
/* getpid() should never return. */
EXPECT_EQ(0, syscall(__NR_getpid));
}
TEST(get_action_avail)
{
__u32 actions[] = { SECCOMP_RET_KILL_THREAD, SECCOMP_RET_TRAP,
SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE,
SECCOMP_RET_LOG, SECCOMP_RET_ALLOW };
__u32 unknown_action = 0x10000000U;
int i;
long ret;
ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[0]);
ASSERT_NE(ENOSYS, errno) {
TH_LOG("Kernel does not support seccomp syscall!");
}
ASSERT_NE(EINVAL, errno) {
TH_LOG("Kernel does not support SECCOMP_GET_ACTION_AVAIL operation!");
}
EXPECT_EQ(ret, 0);
for (i = 0; i < ARRAY_SIZE(actions); i++) {
ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[i]);
EXPECT_EQ(ret, 0) {
TH_LOG("Expected action (0x%X) not available!",
actions[i]);
}
}
/* Check that an unknown action is handled properly (EOPNOTSUPP) */
ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &unknown_action);
EXPECT_EQ(ret, -1);
EXPECT_EQ(errno, EOPNOTSUPP);
}
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()) {
XFAIL(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)
XFAIL(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_trap_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 116983961184613L
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_trap_syscall(__NR_getpid, 0) < 0)
exit(1);
ret = syscall(__NR_getpid);
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_trap_syscall(__NR_getpid,
SECCOMP_FILTER_FLAG_NEW_LISTENER);
ASSERT_GE(listener, 0);
/* Installing a second listener in the chain should EBUSY */
EXPECT_EQ(user_trap_syscall(__NR_getpid,
SECCOMP_FILTER_FLAG_NEW_LISTENER),
-1);
EXPECT_EQ(errno, EBUSY);
pid = fork();
ASSERT_GE(pid, 0);
if (pid == 0) {
ret = syscall(__NR_getpid);
exit(ret != USER_NOTIF_MAGIC);
}
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_getpid);
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_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_trap_syscall(__NR_getpid,
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_getpid);
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");
}
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_trap_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]);
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);
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_trap_syscall(__NR_getpid,
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_getpid);
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);
listener = user_trap_syscall(__NR_getpid, SECCOMP_FILTER_FLAG_NEW_LISTENER);
ASSERT_GE(listener, 0);
pid = fork();
ASSERT_GE(pid, 0);
if (pid == 0)
exit(syscall(__NR_getpid) != 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_trap_syscall(__NR_getpid, SECCOMP_FILTER_FLAG_NEW_LISTENER);
ASSERT_GE(listener, 0);
pid = fork();
ASSERT_GE(pid, 0);
if (pid == 0) {
ASSERT_EQ(unshare(CLONE_NEWPID), 0);
pid2 = fork();
ASSERT_GE(pid2, 0);
if (pid2 == 0)
exit(syscall(__NR_getpid) != 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. */
EXPECT_EQ(unshare(CLONE_NEWPID), 0);
EXPECT_EQ(errno, 0);
pid2 = fork();
EXPECT_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".
*/
ASSERT_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);
listener = user_trap_syscall(__NR_getpid, SECCOMP_FILTER_FLAG_NEW_LISTENER);
ASSERT_GE(listener, 0);
pid = fork();
ASSERT_GE(pid, 0);
if (pid == 0)
exit(syscall(__NR_getpid) != 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));
}
/*
* TODO:
* - add microbenchmarks
* - 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
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