blob: 009a2e192229f1725d4e370cfdf54c4734855589 [file] [log] [blame] [raw]
/* SPDX-License-Identifier: LGPL-2.1+ */
#include <poll.h>
#include <sched.h>
#include <stdlib.h>
#include <sys/eventfd.h>
#include <sys/mman.h>
#include <sys/personality.h>
#include <sys/shm.h>
#include <sys/types.h>
#include <unistd.h>
#include "alloc-util.h"
#include "fd-util.h"
#include "macro.h"
#include "missing.h"
#include "nsflags.h"
#include "process-util.h"
#include "raw-clone.h"
#include "rm-rf.h"
#include "seccomp-util.h"
#include "set.h"
#include "string-util.h"
#include "umask-util.h"
#include "util.h"
#include "virt.h"
#if SCMP_SYS(socket) < 0 || defined(__i386__) || defined(__s390x__) || defined(__s390__)
/* On these archs, socket() is implemented via the socketcall() syscall multiplexer,
* and we can't restrict it hence via seccomp. */
# define SECCOMP_RESTRICT_ADDRESS_FAMILIES_BROKEN 1
#else
# define SECCOMP_RESTRICT_ADDRESS_FAMILIES_BROKEN 0
#endif
static void test_seccomp_arch_to_string(void) {
uint32_t a, b;
const char *name;
a = seccomp_arch_native();
assert_se(a > 0);
name = seccomp_arch_to_string(a);
assert_se(name);
assert_se(seccomp_arch_from_string(name, &b) >= 0);
assert_se(a == b);
}
static void test_architecture_table(void) {
const char *n, *n2;
NULSTR_FOREACH(n,
"native\0"
"x86\0"
"x86-64\0"
"x32\0"
"arm\0"
"arm64\0"
"mips\0"
"mips64\0"
"mips64-n32\0"
"mips-le\0"
"mips64-le\0"
"mips64-le-n32\0"
"ppc\0"
"ppc64\0"
"ppc64-le\0"
"s390\0"
"s390x\0") {
uint32_t c;
assert_se(seccomp_arch_from_string(n, &c) >= 0);
n2 = seccomp_arch_to_string(c);
log_info("seccomp-arch: %s → 0x%"PRIx32" → %s", n, c, n2);
assert_se(streq_ptr(n, n2));
}
}
static void test_syscall_filter_set_find(void) {
assert_se(!syscall_filter_set_find(NULL));
assert_se(!syscall_filter_set_find(""));
assert_se(!syscall_filter_set_find("quux"));
assert_se(!syscall_filter_set_find("@quux"));
assert_se(syscall_filter_set_find("@clock") == syscall_filter_sets + SYSCALL_FILTER_SET_CLOCK);
assert_se(syscall_filter_set_find("@default") == syscall_filter_sets + SYSCALL_FILTER_SET_DEFAULT);
assert_se(syscall_filter_set_find("@raw-io") == syscall_filter_sets + SYSCALL_FILTER_SET_RAW_IO);
}
static void test_filter_sets(void) {
unsigned i;
int r;
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
for (i = 0; i < _SYSCALL_FILTER_SET_MAX; i++) {
pid_t pid;
log_info("Testing %s", syscall_filter_sets[i].name);
pid = fork();
assert_se(pid >= 0);
if (pid == 0) { /* Child? */
int fd;
/* If we look at the default set (or one that includes it), whitelist instead of blacklist */
if (IN_SET(i, SYSCALL_FILTER_SET_DEFAULT, SYSCALL_FILTER_SET_SYSTEM_SERVICE))
r = seccomp_load_syscall_filter_set(SCMP_ACT_ERRNO(EUCLEAN), syscall_filter_sets + i, SCMP_ACT_ALLOW, true);
else
r = seccomp_load_syscall_filter_set(SCMP_ACT_ALLOW, syscall_filter_sets + i, SCMP_ACT_ERRNO(EUCLEAN), true);
if (r < 0)
_exit(EXIT_FAILURE);
/* Test the sycall filter with one random system call */
fd = eventfd(0, EFD_NONBLOCK|EFD_CLOEXEC);
if (IN_SET(i, SYSCALL_FILTER_SET_IO_EVENT, SYSCALL_FILTER_SET_DEFAULT))
assert_se(fd < 0 && errno == EUCLEAN);
else {
assert_se(fd >= 0);
safe_close(fd);
}
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check(syscall_filter_sets[i].name, pid, WAIT_LOG) == EXIT_SUCCESS);
}
}
static void test_restrict_namespace(void) {
char *s = NULL;
unsigned long ul;
pid_t pid;
assert_se(namespace_flags_to_string(0, &s) == 0 && streq(s, ""));
s = mfree(s);
assert_se(namespace_flags_to_string(CLONE_NEWNS, &s) == 0 && streq(s, "mnt"));
s = mfree(s);
assert_se(namespace_flags_to_string(CLONE_NEWNS|CLONE_NEWIPC, &s) == 0 && streq(s, "ipc mnt"));
s = mfree(s);
assert_se(namespace_flags_to_string(CLONE_NEWCGROUP, &s) == 0 && streq(s, "cgroup"));
s = mfree(s);
assert_se(namespace_flags_from_string("mnt", &ul) == 0 && ul == CLONE_NEWNS);
assert_se(namespace_flags_from_string(NULL, &ul) == 0 && ul == 0);
assert_se(namespace_flags_from_string("", &ul) == 0 && ul == 0);
assert_se(namespace_flags_from_string("uts", &ul) == 0 && ul == CLONE_NEWUTS);
assert_se(namespace_flags_from_string("mnt uts ipc", &ul) == 0 && ul == (CLONE_NEWNS|CLONE_NEWUTS|CLONE_NEWIPC));
assert_se(namespace_flags_to_string(CLONE_NEWUTS, &s) == 0 && streq(s, "uts"));
assert_se(namespace_flags_from_string(s, &ul) == 0 && ul == CLONE_NEWUTS);
s = mfree(s);
assert_se(namespace_flags_from_string("ipc", &ul) == 0 && ul == CLONE_NEWIPC);
assert_se(namespace_flags_to_string(ul, &s) == 0 && streq(s, "ipc"));
s = mfree(s);
assert_se(namespace_flags_to_string(NAMESPACE_FLAGS_ALL, &s) == 0);
assert_se(streq(s, "cgroup ipc net mnt pid user uts"));
assert_se(namespace_flags_from_string(s, &ul) == 0 && ul == NAMESPACE_FLAGS_ALL);
s = mfree(s);
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
assert_se(seccomp_restrict_namespaces(CLONE_NEWNS|CLONE_NEWNET) >= 0);
assert_se(unshare(CLONE_NEWNS) == 0);
assert_se(unshare(CLONE_NEWNET) == 0);
assert_se(unshare(CLONE_NEWUTS) == -1);
assert_se(errno == EPERM);
assert_se(unshare(CLONE_NEWIPC) == -1);
assert_se(errno == EPERM);
assert_se(unshare(CLONE_NEWNET|CLONE_NEWUTS) == -1);
assert_se(errno == EPERM);
/* We use fd 0 (stdin) here, which of course will fail with EINVAL on setns(). Except of course our
* seccomp filter worked, and hits first and makes it return EPERM */
assert_se(setns(0, CLONE_NEWNS) == -1);
assert_se(errno == EINVAL);
assert_se(setns(0, CLONE_NEWNET) == -1);
assert_se(errno == EINVAL);
assert_se(setns(0, CLONE_NEWUTS) == -1);
assert_se(errno == EPERM);
assert_se(setns(0, CLONE_NEWIPC) == -1);
assert_se(errno == EPERM);
assert_se(setns(0, CLONE_NEWNET|CLONE_NEWUTS) == -1);
assert_se(errno == EPERM);
assert_se(setns(0, 0) == -1);
assert_se(errno == EPERM);
pid = raw_clone(CLONE_NEWNS);
assert_se(pid >= 0);
if (pid == 0)
_exit(EXIT_SUCCESS);
pid = raw_clone(CLONE_NEWNET);
assert_se(pid >= 0);
if (pid == 0)
_exit(EXIT_SUCCESS);
pid = raw_clone(CLONE_NEWUTS);
assert_se(pid < 0);
assert_se(errno == EPERM);
pid = raw_clone(CLONE_NEWIPC);
assert_se(pid < 0);
assert_se(errno == EPERM);
pid = raw_clone(CLONE_NEWNET|CLONE_NEWUTS);
assert_se(pid < 0);
assert_se(errno == EPERM);
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("nsseccomp", pid, WAIT_LOG) == EXIT_SUCCESS);
}
static void test_protect_sysctl(void) {
pid_t pid;
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
if (detect_container() > 0) /* in containers _sysctl() is likely missing anyway */
return;
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
#if defined __NR__sysctl && __NR__sysctl >= 0
assert_se(syscall(__NR__sysctl, NULL) < 0);
assert_se(errno == EFAULT);
#endif
assert_se(seccomp_protect_sysctl() >= 0);
#if defined __NR__sysctl && __NR__sysctl >= 0
assert_se(syscall(__NR__sysctl, 0, 0, 0) < 0);
assert_se(errno == EPERM);
#endif
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("sysctlseccomp", pid, WAIT_LOG) == EXIT_SUCCESS);
}
static void test_restrict_address_families(void) {
pid_t pid;
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
int fd;
Set *s;
fd = socket(AF_INET, SOCK_DGRAM, 0);
assert_se(fd >= 0);
safe_close(fd);
fd = socket(AF_UNIX, SOCK_DGRAM, 0);
assert_se(fd >= 0);
safe_close(fd);
fd = socket(AF_NETLINK, SOCK_DGRAM, 0);
assert_se(fd >= 0);
safe_close(fd);
assert_se(s = set_new(NULL));
assert_se(set_put(s, INT_TO_PTR(AF_UNIX)) >= 0);
assert_se(seccomp_restrict_address_families(s, false) >= 0);
fd = socket(AF_INET, SOCK_DGRAM, 0);
assert_se(fd >= 0);
safe_close(fd);
fd = socket(AF_UNIX, SOCK_DGRAM, 0);
#if SECCOMP_RESTRICT_ADDRESS_FAMILIES_BROKEN
assert_se(fd >= 0);
safe_close(fd);
#else
assert_se(fd < 0);
assert_se(errno == EAFNOSUPPORT);
#endif
fd = socket(AF_NETLINK, SOCK_DGRAM, 0);
assert_se(fd >= 0);
safe_close(fd);
set_clear(s);
assert_se(set_put(s, INT_TO_PTR(AF_INET)) >= 0);
assert_se(seccomp_restrict_address_families(s, true) >= 0);
fd = socket(AF_INET, SOCK_DGRAM, 0);
assert_se(fd >= 0);
safe_close(fd);
fd = socket(AF_UNIX, SOCK_DGRAM, 0);
#if SECCOMP_RESTRICT_ADDRESS_FAMILIES_BROKEN
assert_se(fd >= 0);
safe_close(fd);
#else
assert_se(fd < 0);
assert_se(errno == EAFNOSUPPORT);
#endif
fd = socket(AF_NETLINK, SOCK_DGRAM, 0);
#if SECCOMP_RESTRICT_ADDRESS_FAMILIES_BROKEN
assert_se(fd >= 0);
safe_close(fd);
#else
assert_se(fd < 0);
assert_se(errno == EAFNOSUPPORT);
#endif
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("socketseccomp", pid, WAIT_LOG) == EXIT_SUCCESS);
}
static void test_restrict_realtime(void) {
pid_t pid;
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
if (detect_container() > 0) /* in containers RT privs are likely missing anyway */
return;
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
assert_se(sched_setscheduler(0, SCHED_FIFO, &(struct sched_param) { .sched_priority = 1 }) >= 0);
assert_se(sched_setscheduler(0, SCHED_RR, &(struct sched_param) { .sched_priority = 1 }) >= 0);
assert_se(sched_setscheduler(0, SCHED_IDLE, &(struct sched_param) { .sched_priority = 0 }) >= 0);
assert_se(sched_setscheduler(0, SCHED_BATCH, &(struct sched_param) { .sched_priority = 0 }) >= 0);
assert_se(sched_setscheduler(0, SCHED_OTHER, &(struct sched_param) {}) >= 0);
assert_se(seccomp_restrict_realtime() >= 0);
assert_se(sched_setscheduler(0, SCHED_IDLE, &(struct sched_param) { .sched_priority = 0 }) >= 0);
assert_se(sched_setscheduler(0, SCHED_BATCH, &(struct sched_param) { .sched_priority = 0 }) >= 0);
assert_se(sched_setscheduler(0, SCHED_OTHER, &(struct sched_param) {}) >= 0);
assert_se(sched_setscheduler(0, SCHED_FIFO, &(struct sched_param) { .sched_priority = 1 }) < 0);
assert_se(errno == EPERM);
assert_se(sched_setscheduler(0, SCHED_RR, &(struct sched_param) { .sched_priority = 1 }) < 0);
assert_se(errno == EPERM);
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("realtimeseccomp", pid, WAIT_LOG) == EXIT_SUCCESS);
}
static void test_memory_deny_write_execute_mmap(void) {
pid_t pid;
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
void *p;
p = mmap(NULL, page_size(), PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_ANONYMOUS, -1,0);
assert_se(p != MAP_FAILED);
assert_se(munmap(p, page_size()) >= 0);
p = mmap(NULL, page_size(), PROT_WRITE|PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1,0);
assert_se(p != MAP_FAILED);
assert_se(munmap(p, page_size()) >= 0);
assert_se(seccomp_memory_deny_write_execute() >= 0);
p = mmap(NULL, page_size(), PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_ANONYMOUS, -1,0);
#if defined(__x86_64__) || defined(__i386__) || defined(__powerpc64__) || defined(__arm__) || defined(__aarch64__)
assert_se(p == MAP_FAILED);
assert_se(errno == EPERM);
#else /* unknown architectures */
assert_se(p != MAP_FAILED);
assert_se(munmap(p, page_size()) >= 0);
#endif
p = mmap(NULL, page_size(), PROT_WRITE|PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1,0);
assert_se(p != MAP_FAILED);
assert_se(munmap(p, page_size()) >= 0);
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("memoryseccomp-mmap", pid, WAIT_LOG) == EXIT_SUCCESS);
}
static void test_memory_deny_write_execute_shmat(void) {
int shmid;
pid_t pid;
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
shmid = shmget(IPC_PRIVATE, page_size(), 0);
assert_se(shmid >= 0);
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
void *p;
p = shmat(shmid, NULL, 0);
assert_se(p != MAP_FAILED);
assert_se(shmdt(p) == 0);
p = shmat(shmid, NULL, SHM_EXEC);
assert_se(p != MAP_FAILED);
assert_se(shmdt(p) == 0);
assert_se(seccomp_memory_deny_write_execute() >= 0);
p = shmat(shmid, NULL, SHM_EXEC);
#if defined(__x86_64__) || defined(__arm__) || defined(__aarch64__)
assert_se(p == MAP_FAILED);
assert_se(errno == EPERM);
#else /* __i386__, __powerpc64__, and "unknown" architectures */
assert_se(p != MAP_FAILED);
assert_se(shmdt(p) == 0);
#endif
p = shmat(shmid, NULL, 0);
assert_se(p != MAP_FAILED);
assert_se(shmdt(p) == 0);
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("memoryseccomp-shmat", pid, WAIT_LOG) == EXIT_SUCCESS);
}
static void test_restrict_archs(void) {
pid_t pid;
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
_cleanup_set_free_ Set *s = NULL;
assert_se(access("/", F_OK) >= 0);
assert_se(s = set_new(NULL));
#ifdef __x86_64__
assert_se(set_put(s, UINT32_TO_PTR(SCMP_ARCH_X86+1)) >= 0);
#endif
assert_se(seccomp_restrict_archs(s) >= 0);
assert_se(access("/", F_OK) >= 0);
assert_se(seccomp_restrict_archs(NULL) >= 0);
assert_se(access("/", F_OK) >= 0);
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("archseccomp", pid, WAIT_LOG) == EXIT_SUCCESS);
}
static void test_load_syscall_filter_set_raw(void) {
pid_t pid;
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
_cleanup_hashmap_free_ Hashmap *s = NULL;
assert_se(access("/", F_OK) >= 0);
assert_se(poll(NULL, 0, 0) == 0);
assert_se(seccomp_load_syscall_filter_set_raw(SCMP_ACT_ALLOW, NULL, SCMP_ACT_KILL, true) >= 0);
assert_se(access("/", F_OK) >= 0);
assert_se(poll(NULL, 0, 0) == 0);
assert_se(s = hashmap_new(NULL));
#if SCMP_SYS(access) >= 0
assert_se(hashmap_put(s, UINT32_TO_PTR(__NR_access + 1), INT_TO_PTR(-1)) >= 0);
#else
assert_se(hashmap_put(s, UINT32_TO_PTR(__NR_faccessat + 1), INT_TO_PTR(-1)) >= 0);
#endif
assert_se(seccomp_load_syscall_filter_set_raw(SCMP_ACT_ALLOW, s, SCMP_ACT_ERRNO(EUCLEAN), true) >= 0);
assert_se(access("/", F_OK) < 0);
assert_se(errno == EUCLEAN);
assert_se(poll(NULL, 0, 0) == 0);
s = hashmap_free(s);
assert_se(s = hashmap_new(NULL));
#if SCMP_SYS(access) >= 0
assert_se(hashmap_put(s, UINT32_TO_PTR(__NR_access + 1), INT_TO_PTR(EILSEQ)) >= 0);
#else
assert_se(hashmap_put(s, UINT32_TO_PTR(__NR_faccessat + 1), INT_TO_PTR(EILSEQ)) >= 0);
#endif
assert_se(seccomp_load_syscall_filter_set_raw(SCMP_ACT_ALLOW, s, SCMP_ACT_ERRNO(EUCLEAN), true) >= 0);
assert_se(access("/", F_OK) < 0);
assert_se(errno == EILSEQ);
assert_se(poll(NULL, 0, 0) == 0);
s = hashmap_free(s);
assert_se(s = hashmap_new(NULL));
#if SCMP_SYS(poll) >= 0
assert_se(hashmap_put(s, UINT32_TO_PTR(__NR_poll + 1), INT_TO_PTR(-1)) >= 0);
#else
assert_se(hashmap_put(s, UINT32_TO_PTR(__NR_ppoll + 1), INT_TO_PTR(-1)) >= 0);
#endif
assert_se(seccomp_load_syscall_filter_set_raw(SCMP_ACT_ALLOW, s, SCMP_ACT_ERRNO(EUNATCH), true) >= 0);
assert_se(access("/", F_OK) < 0);
assert_se(errno == EILSEQ);
assert_se(poll(NULL, 0, 0) < 0);
assert_se(errno == EUNATCH);
s = hashmap_free(s);
assert_se(s = hashmap_new(NULL));
#if SCMP_SYS(poll) >= 0
assert_se(hashmap_put(s, UINT32_TO_PTR(__NR_poll + 1), INT_TO_PTR(EILSEQ)) >= 0);
#else
assert_se(hashmap_put(s, UINT32_TO_PTR(__NR_ppoll + 1), INT_TO_PTR(EILSEQ)) >= 0);
#endif
assert_se(seccomp_load_syscall_filter_set_raw(SCMP_ACT_ALLOW, s, SCMP_ACT_ERRNO(EUNATCH), true) >= 0);
assert_se(access("/", F_OK) < 0);
assert_se(errno == EILSEQ);
assert_se(poll(NULL, 0, 0) < 0);
assert_se(errno == EILSEQ);
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("syscallrawseccomp", pid, WAIT_LOG) == EXIT_SUCCESS);
}
static void test_lock_personality(void) {
unsigned long current;
pid_t pid;
if (!is_seccomp_available())
return;
if (geteuid() != 0)
return;
assert_se(opinionated_personality(&current) >= 0);
log_info("current personality=%lu", current);
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
assert_se(seccomp_lock_personality(current) >= 0);
assert_se((unsigned long) safe_personality(current) == current);
/* Note, we also test that safe_personality() works correctly, by checkig whether errno is properly
* set, in addition to the return value */
errno = 0;
assert_se(safe_personality(PER_LINUX | ADDR_NO_RANDOMIZE) == -EPERM);
assert_se(errno == EPERM);
assert_se(safe_personality(PER_LINUX | MMAP_PAGE_ZERO) == -EPERM);
assert_se(safe_personality(PER_LINUX | ADDR_COMPAT_LAYOUT) == -EPERM);
assert_se(safe_personality(PER_LINUX | READ_IMPLIES_EXEC) == -EPERM);
assert_se(safe_personality(PER_LINUX_32BIT) == -EPERM);
assert_se(safe_personality(PER_SVR4) == -EPERM);
assert_se(safe_personality(PER_BSD) == -EPERM);
assert_se(safe_personality(current == PER_LINUX ? PER_LINUX32 : PER_LINUX) == -EPERM);
assert_se(safe_personality(PER_LINUX32_3GB) == -EPERM);
assert_se(safe_personality(PER_UW7) == -EPERM);
assert_se(safe_personality(0x42) == -EPERM);
assert_se(safe_personality(PERSONALITY_INVALID) == -EPERM); /* maybe remove this later */
assert_se((unsigned long) personality(current) == current);
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("lockpersonalityseccomp", pid, WAIT_LOG) == EXIT_SUCCESS);
}
static void test_filter_sets_ordered(void) {
size_t i;
/* Ensure "@default" always remains at the beginning of the list */
assert_se(SYSCALL_FILTER_SET_DEFAULT == 0);
assert_se(streq(syscall_filter_sets[0].name, "@default"));
for (i = 0; i < _SYSCALL_FILTER_SET_MAX; i++) {
const char *k, *p = NULL;
/* Make sure each group has a description */
assert_se(!isempty(syscall_filter_sets[0].help));
/* Make sure the groups are ordered alphabetically, except for the first entry */
assert_se(i < 2 || strcmp(syscall_filter_sets[i-1].name, syscall_filter_sets[i].name) < 0);
NULSTR_FOREACH(k, syscall_filter_sets[i].value) {
/* Ensure each syscall list is in itself ordered, but groups before names */
assert_se(!p ||
(*p == '@' && *k != '@') ||
(((*p == '@' && *k == '@') ||
(*p != '@' && *k != '@')) &&
strcmp(p, k) < 0));
p = k;
}
}
}
static int mkostemp_safe(char *pattern) {
_unused_ _cleanup_umask_ mode_t u = umask(0077);
int fd;
assert(pattern);
fd = mkostemp(pattern, O_CLOEXEC);
if (fd < 0)
return -errno;
return fd;
}
static int real_open(const char *path, int flags, mode_t mode) {
/* glibc internally calls openat() when open() is requested. Let's hence define our own wrapper for
* testing purposes that calls the real syscall, on architectures where SYS_open is defined. On
* other architectures, let's just fall back to the glibc call. */
#ifdef SYS_open
return (int) syscall(SYS_open, path, flags, mode);
#else
return open(path, flags, mode);
#endif
}
static void test_restrict_suid_sgid(void) {
pid_t pid;
log_info("/* %s */", __func__);
if (!is_seccomp_available()) {
log_notice("Seccomp not available, skipping %s", __func__);
return;
}
if (geteuid() != 0) {
log_notice("Not root, skipping %s", __func__);
return;
}
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
char path[] = "/tmp/suidsgidXXXXXX", dir[] = "/tmp/suidsgiddirXXXXXX";
int fd = -1, k = -1;
const char *z;
fd = mkostemp_safe(path);
assert_se(fd >= 0);
assert_se(mkdtemp(dir));
z = strjoina(dir, "/test");
assert_se(chmod(path, 0755 | S_ISUID) >= 0);
assert_se(chmod(path, 0755 | S_ISGID) >= 0);
assert_se(chmod(path, 0755 | S_ISGID | S_ISUID) >= 0);
assert_se(chmod(path, 0755) >= 0);
assert_se(fchmod(fd, 0755 | S_ISUID) >= 0);
assert_se(fchmod(fd, 0755 | S_ISGID) >= 0);
assert_se(fchmod(fd, 0755 | S_ISGID | S_ISUID) >= 0);
assert_se(fchmod(fd, 0755) >= 0);
assert_se(fchmodat(AT_FDCWD, path, 0755 | S_ISUID, 0) >= 0);
assert_se(fchmodat(AT_FDCWD, path, 0755 | S_ISGID, 0) >= 0);
assert_se(fchmodat(AT_FDCWD, path, 0755 | S_ISGID | S_ISUID, 0) >= 0);
assert_se(fchmodat(AT_FDCWD, path, 0755, 0) >= 0);
k = real_open(z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISUID);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = real_open(z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISGID);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = real_open(z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISUID | S_ISGID);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = real_open(z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = creat(z, 0644 | S_ISUID);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = creat(z, 0644 | S_ISGID);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = creat(z, 0644 | S_ISUID | S_ISGID);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = creat(z, 0644);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = openat(AT_FDCWD, z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISUID);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = openat(AT_FDCWD, z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISGID);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = openat(AT_FDCWD, z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISUID | S_ISGID);
k = safe_close(k);
assert_se(unlink(z) >= 0);
k = openat(AT_FDCWD, z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644);
k = safe_close(k);
assert_se(unlink(z) >= 0);
assert_se(mkdir(z, 0755 | S_ISUID) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mkdir(z, 0755 | S_ISGID) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mkdir(z, 0755 | S_ISUID | S_ISGID) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mkdir(z, 0755) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mkdirat(AT_FDCWD, z, 0755 | S_ISUID) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mkdirat(AT_FDCWD, z, 0755 | S_ISGID) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mkdirat(AT_FDCWD, z, 0755 | S_ISUID | S_ISGID) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mkdirat(AT_FDCWD, z, 0755) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mknod(z, S_IFREG | 0755 | S_ISUID, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(mknod(z, S_IFREG | 0755 | S_ISGID, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(mknod(z, S_IFREG | 0755 | S_ISUID | S_ISGID, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(mknod(z, S_IFREG | 0755, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(mknodat(AT_FDCWD, z, S_IFREG | 0755 | S_ISUID, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(mknodat(AT_FDCWD, z, S_IFREG | 0755 | S_ISGID, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(mknodat(AT_FDCWD, z, S_IFREG | 0755 | S_ISUID | S_ISGID, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(mknodat(AT_FDCWD, z, S_IFREG | 0755, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(seccomp_restrict_suid_sgid() >= 0);
assert_se(chmod(path, 0775 | S_ISUID) < 0 && errno == EPERM);
assert_se(chmod(path, 0775 | S_ISGID) < 0 && errno == EPERM);
assert_se(chmod(path, 0775 | S_ISGID | S_ISUID) < 0 && errno == EPERM);
assert_se(chmod(path, 0775) >= 0);
assert_se(fchmod(fd, 0775 | S_ISUID) < 0 && errno == EPERM);
assert_se(fchmod(fd, 0775 | S_ISGID) < 0 && errno == EPERM);
assert_se(fchmod(fd, 0775 | S_ISGID | S_ISUID) < 0 && errno == EPERM);
assert_se(fchmod(fd, 0775) >= 0);
assert_se(fchmodat(AT_FDCWD, path, 0755 | S_ISUID, 0) < 0 && errno == EPERM);
assert_se(fchmodat(AT_FDCWD, path, 0755 | S_ISGID, 0) < 0 && errno == EPERM);
assert_se(fchmodat(AT_FDCWD, path, 0755 | S_ISGID | S_ISUID, 0) < 0 && errno == EPERM);
assert_se(fchmodat(AT_FDCWD, path, 0755, 0) >= 0);
assert_se(real_open(z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISUID) < 0 && errno == EPERM);
assert_se(real_open(z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISGID) < 0 && errno == EPERM);
assert_se(real_open(z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISUID | S_ISGID) < 0 && errno == EPERM);
k = real_open(z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644);
k = safe_close(k);
assert_se(unlink(z) >= 0);
assert_se(creat(z, 0644 | S_ISUID) < 0 && errno == EPERM);
assert_se(creat(z, 0644 | S_ISGID) < 0 && errno == EPERM);
assert_se(creat(z, 0644 | S_ISUID | S_ISGID) < 0 && errno == EPERM);
k = creat(z, 0644);
k = safe_close(k);
assert_se(unlink(z) >= 0);
assert_se(openat(AT_FDCWD, z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISUID) < 0 && errno == EPERM);
assert_se(openat(AT_FDCWD, z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISGID) < 0 && errno == EPERM);
assert_se(openat(AT_FDCWD, z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644 | S_ISUID | S_ISGID) < 0 && errno == EPERM);
k = openat(AT_FDCWD, z, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL, 0644);
k = safe_close(k);
assert_se(unlink(z) >= 0);
assert_se(mkdir(z, 0755 | S_ISUID) < 0 && errno == EPERM);
assert_se(mkdir(z, 0755 | S_ISGID) < 0 && errno == EPERM);
assert_se(mkdir(z, 0755 | S_ISUID | S_ISGID) < 0 && errno == EPERM);
assert_se(mkdir(z, 0755) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mkdirat(AT_FDCWD, z, 0755 | S_ISUID) < 0 && errno == EPERM);
assert_se(mkdirat(AT_FDCWD, z, 0755 | S_ISGID) < 0 && errno == EPERM);
assert_se(mkdirat(AT_FDCWD, z, 0755 | S_ISUID | S_ISGID) < 0 && errno == EPERM);
assert_se(mkdirat(AT_FDCWD, z, 0755) >= 0);
assert_se(rmdir(z) >= 0);
assert_se(mknod(z, S_IFREG | 0755 | S_ISUID, 0) < 0 && errno == EPERM);
assert_se(mknod(z, S_IFREG | 0755 | S_ISGID, 0) < 0 && errno == EPERM);
assert_se(mknod(z, S_IFREG | 0755 | S_ISUID | S_ISGID, 0) < 0 && errno == EPERM);
assert_se(mknod(z, S_IFREG | 0755, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(mknodat(AT_FDCWD, z, S_IFREG | 0755 | S_ISUID, 0) < 0 && errno == EPERM);
assert_se(mknodat(AT_FDCWD, z, S_IFREG | 0755 | S_ISGID, 0) < 0 && errno == EPERM);
assert_se(mknodat(AT_FDCWD, z, S_IFREG | 0755 | S_ISUID | S_ISGID, 0) < 0 && errno == EPERM);
assert_se(mknodat(AT_FDCWD, z, S_IFREG | 0755, 0) >= 0);
assert_se(unlink(z) >= 0);
assert_se(unlink(path) >= 0);
assert_se(rm_rf(dir, REMOVE_ROOT|REMOVE_PHYSICAL) >= 0);
_exit(EXIT_SUCCESS);
}
assert_se(wait_for_terminate_and_check("suidsgidseccomp", pid, WAIT_LOG) == EXIT_SUCCESS);
}
int main(int argc, char *argv[]) {
log_set_max_level(LOG_DEBUG);
test_seccomp_arch_to_string();
test_architecture_table();
test_syscall_filter_set_find();
test_filter_sets();
test_restrict_namespace();
test_protect_sysctl();
test_restrict_address_families();
test_restrict_realtime();
test_memory_deny_write_execute_mmap();
test_memory_deny_write_execute_shmat();
test_restrict_archs();
test_load_syscall_filter_set_raw();
test_lock_personality();
test_filter_sets_ordered();
test_restrict_suid_sgid();
return 0;
}