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2553 lines (2117 loc) · 75 KB
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/* Copyright 2016 The ChromiumOS Authors
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*
* Test platform independent logic of Minijail using gtest.
*/
#include <errno.h>
#include <dirent.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <gtest/gtest.h>
#include <functional>
#include <map>
#include <set>
#include <string>
#include "landlock_util.h"
#include "libminijail-private.h"
#include "libminijail.h"
#include "scoped_minijail.h"
#include "test_util.h"
#include "unittest_util.h"
#include "util.h"
namespace {
#if defined(__ANDROID__)
#define ROOT_PREFIX "/system"
#else
#define ROOT_PREFIX ""
#endif
constexpr char kShellPath[] = ROOT_PREFIX "/bin/sh";
constexpr char kCatPath[] = ROOT_PREFIX "/bin/cat";
constexpr char kPreloadPath[] = "./libminijailpreload.so";
constexpr size_t kBufferSize = 128;
constexpr bool kCompiledWithCoverage =
#if defined(CROS_CODE_COVERAGE_ENABLED)
true;
#else
false;
#endif
std::set<pid_t> GetProcessSubtreePids(pid_t root_pid) {
std::set<pid_t> pids{root_pid};
bool progress = false;
do {
progress = false;
DIR* d = opendir("/proc");
if (!d)
pdie("opendir(\"/proc\")");
struct dirent* dir_entry;
while ((dir_entry = readdir(d)) != nullptr) {
if (dir_entry->d_type != DT_DIR)
continue;
char* end;
const int pid = strtol(dir_entry->d_name, &end, 10);
if (*end != '\0')
continue;
std::string path = "/proc/" + std::to_string(pid) + "/stat";
FILE* f = fopen(path.c_str(), "re");
if (!f) {
if (errno == ENOENT) {
// This loop is inherently racy, since PIDs can be reaped in the
// middle of this. Not being able to find one /proc/PID/stat file is
// completely normal.
continue;
}
pdie("fopen(%s)", path.c_str());
}
pid_t ppid;
int ret = fscanf(f, "%*d (%*[^)]) %*c %d", &ppid);
fclose(f);
if (ret != 1) {
continue;
}
if (pids.find(ppid) == pids.end())
continue;
progress |= pids.insert(pid).second;
}
closedir(d);
} while (progress);
return pids;
}
std::map<std::string, std::string> GetNamespaces(
pid_t pid, const std::vector<std::string>& namespace_names) {
std::map<std::string, std::string> namespaces;
char buf[kBufferSize];
for (const auto& namespace_name : namespace_names) {
std::string path = "/proc/" + std::to_string(pid) + "/ns/" + namespace_name;
ssize_t len = readlink(path.c_str(), buf, sizeof(buf));
if (len == -1)
pdie("readlink(\"%s\")", path.c_str());
namespaces.emplace(namespace_name, std::string(buf, len));
}
return namespaces;
}
void set_preload_path(minijail* j) {
// We need to get the absolute path because entering a new mntns will
// implicitly chdir(/) for us.
char* preload_path = realpath(kPreloadPath, nullptr);
ASSERT_NE(preload_path, nullptr);
minijail_set_preload_path(j, preload_path);
free(preload_path);
}
} // namespace
/* Silence unused variable warnings. */
TEST(silence, silence_unused) {
EXPECT_STREQ(kLdPreloadEnvVar, kLdPreloadEnvVar);
EXPECT_STREQ(kFdEnvVar, kFdEnvVar);
EXPECT_STRNE(kFdEnvVar, kLdPreloadEnvVar);
}
TEST(consumebytes, zero) {
char buf[1024];
size_t len = sizeof(buf);
char* pos = &buf[0];
EXPECT_NE(nullptr, consumebytes(0, &pos, &len));
EXPECT_EQ(&buf[0], pos);
EXPECT_EQ(sizeof(buf), len);
}
TEST(consumebytes, exact) {
char buf[1024];
size_t len = sizeof(buf);
char* pos = &buf[0];
/* One past the end since it consumes the whole buffer. */
char* end = &buf[sizeof(buf)];
EXPECT_NE(nullptr, consumebytes(len, &pos, &len));
EXPECT_EQ((size_t)0, len);
EXPECT_EQ(end, pos);
}
TEST(consumebytes, half) {
char buf[1024];
size_t len = sizeof(buf);
char* pos = &buf[0];
/* One past the end since it consumes the whole buffer. */
char* end = &buf[sizeof(buf) / 2];
EXPECT_NE(nullptr, consumebytes(len / 2, &pos, &len));
EXPECT_EQ(sizeof(buf) / 2, len);
EXPECT_EQ(end, pos);
}
TEST(consumebytes, toolong) {
char buf[1024];
size_t len = sizeof(buf);
char* pos = &buf[0];
/* One past the end since it consumes the whole buffer. */
EXPECT_EQ(nullptr, consumebytes(len + 1, &pos, &len));
EXPECT_EQ(sizeof(buf), len);
EXPECT_EQ(&buf[0], pos);
}
TEST(consumestr, zero) {
char buf[1024];
size_t len = 0;
char* pos = &buf[0];
memset(buf, 0xff, sizeof(buf));
EXPECT_EQ(nullptr, consumestr(&pos, &len));
EXPECT_EQ((size_t)0, len);
EXPECT_EQ(&buf[0], pos);
}
TEST(consumestr, nonul) {
char buf[1024];
size_t len = sizeof(buf);
char* pos = &buf[0];
memset(buf, 0xff, sizeof(buf));
EXPECT_EQ(nullptr, consumestr(&pos, &len));
EXPECT_EQ(sizeof(buf), len);
EXPECT_EQ(&buf[0], pos);
}
TEST(consumestr, full) {
char buf[1024];
size_t len = sizeof(buf);
char* pos = &buf[0];
memset(buf, 0xff, sizeof(buf));
buf[sizeof(buf) - 1] = '\0';
EXPECT_EQ((void*)buf, consumestr(&pos, &len));
EXPECT_EQ((size_t)0, len);
EXPECT_EQ(&buf[sizeof(buf)], pos);
}
TEST(consumestr, trailing_nul) {
char buf[1024];
size_t len = sizeof(buf) - 1;
char* pos = &buf[0];
memset(buf, 0xff, sizeof(buf));
buf[sizeof(buf) - 1] = '\0';
EXPECT_EQ(nullptr, consumestr(&pos, &len));
EXPECT_EQ(sizeof(buf) - 1, len);
EXPECT_EQ(&buf[0], pos);
}
class MarshalTest : public ::testing::Test {
protected:
virtual void SetUp() {
m_ = minijail_new();
j_ = minijail_new();
size_ = minijail_size(m_);
}
virtual void TearDown() {
minijail_destroy(m_);
minijail_destroy(j_);
}
char buf_[4096];
struct minijail* m_;
struct minijail* j_;
size_t size_;
};
TEST_F(MarshalTest, empty) {
ASSERT_EQ(0, minijail_marshal(m_, buf_, sizeof(buf_)));
EXPECT_EQ(0, minijail_unmarshal(j_, buf_, size_));
}
TEST_F(MarshalTest, 0xff) {
memset(buf_, 0xff, sizeof(buf_));
/* Should fail on the first consumestr since a NUL will never be found. */
EXPECT_EQ(-EINVAL, minijail_unmarshal(j_, buf_, sizeof(buf_)));
}
TEST_F(MarshalTest, copy_empty) {
ASSERT_EQ(0, minijail_copy_jail(m_, j_));
}
TEST_F(MarshalTest, profile_flags) {
minijail_bind(m_, "/var", "/var", false);
minijail_set_using_minimalistic_mountns(m_);
minijail_set_enable_profile_fs_restrictions(m_);
minijail_add_minimalistic_mountns_fs_rules(m_);
size_ = minijail_size(m_);
for (size_t offset = 0; offset < 8; ++offset) {
do_log(LOG_INFO, "offset: %zu", offset);
ASSERT_EQ(0, minijail_marshal(m_, buf_ + offset, sizeof(buf_) - offset));
EXPECT_EQ(0, minijail_unmarshal(j_, buf_ + offset, size_));
}
}
TEST(KillTest, running_process) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"sh", "-c", "sleep 1000", nullptr};
EXPECT_EQ(minijail_run(j.get(), kShellPath, argv), 0);
EXPECT_EQ(minijail_kill(j.get()), 128 + SIGTERM);
EXPECT_EQ(minijail_kill(j.get()), -ESRCH);
}
TEST(KillTest, process_already_awaited) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"sh", "-c", "sleep 1; exit 42", nullptr};
set_preload_path(j.get());
EXPECT_EQ(minijail_run(j.get(), kShellPath, argv), 0);
EXPECT_EQ(minijail_wait(j.get()), 42);
EXPECT_EQ(minijail_kill(j.get()), -ESRCH);
}
TEST(KillTest, process_already_finished_but_not_awaited) {
int fds[2];
const ScopedMinijail j(minijail_new());
char* const argv[] = {"sh", "-c", "exit 42", nullptr};
set_preload_path(j.get());
ASSERT_EQ(pipe(fds), 0);
EXPECT_EQ(minijail_run(j.get(), kShellPath, argv), 0);
ASSERT_EQ(close(fds[1]), 0);
// Wait for process to finish.
char buf[PIPE_BUF];
EXPECT_EQ(read(fds[0], buf, PIPE_BUF), 0);
EXPECT_EQ(minijail_kill(j.get()), 42);
EXPECT_EQ(minijail_wait(j.get()), -ECHILD);
}
TEST(KillTest, process_not_started) {
const ScopedMinijail j(minijail_new());
EXPECT_EQ(minijail_kill(j.get()), -ECHILD);
}
TEST(WaitTest, return_zero) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"sh", "-c", "exit 0", nullptr};
set_preload_path(j.get());
EXPECT_EQ(minijail_run(j.get(), kShellPath, argv), 0);
EXPECT_EQ(minijail_wait(j.get()), 0);
}
TEST(WaitTest, return_max) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"sh", "-c", "exit 255", nullptr};
set_preload_path(j.get());
EXPECT_EQ(minijail_run(j.get(), kShellPath, argv), 0);
EXPECT_EQ(minijail_wait(j.get()), 255);
}
TEST(WaitTest, return_modulo) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"sh", "-c", "exit 256", nullptr};
set_preload_path(j.get());
EXPECT_EQ(minijail_run(j.get(), kShellPath, argv), 0);
EXPECT_EQ(minijail_wait(j.get()), 0);
}
TEST(WaitTest, killed_by_sigkill) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"sh", "-c", "kill -KILL $$; sleep 1000", nullptr};
set_preload_path(j.get());
EXPECT_EQ(minijail_run(j.get(), kShellPath, argv), 0);
EXPECT_EQ(minijail_wait(j.get()), MINIJAIL_ERR_SIG_BASE + SIGKILL);
}
TEST(WaitTest, killed_by_sigsys) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"sh", "-c", "kill -SYS $$; sleep 1000", nullptr};
set_preload_path(j.get());
EXPECT_EQ(minijail_run(j.get(), kShellPath, argv), 0);
EXPECT_EQ(minijail_wait(j.get()), MINIJAIL_ERR_SECCOMP_VIOLATION);
}
TEST(WaitTest, command_not_found) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"whatever", nullptr};
EXPECT_EQ(minijail_run(j.get(), "command that cannot be found", argv), 0);
EXPECT_EQ(minijail_wait(j.get()), MINIJAIL_ERR_NO_COMMAND);
}
TEST(WaitTest, command_not_run) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"whatever", nullptr};
EXPECT_EQ(minijail_run(j.get(), "/dev/null", argv), 0);
EXPECT_EQ(minijail_wait(j.get()), MINIJAIL_ERR_NO_ACCESS);
}
TEST(WaitTest, no_process) {
const ScopedMinijail j(minijail_new());
EXPECT_EQ(minijail_wait(j.get()), -ECHILD);
}
TEST(WaitTest, can_wait_only_once) {
const ScopedMinijail j(minijail_new());
char* const argv[] = {"sh", "-c", "exit 0", nullptr};
set_preload_path(j.get());
EXPECT_EQ(minijail_run(j.get(), kShellPath, argv), 0);
EXPECT_EQ(minijail_wait(j.get()), 0);
EXPECT_EQ(minijail_wait(j.get()), -ECHILD);
}
TEST(Test, seccomp_logging_emits_warning_to_stderr_when_logging_to_fd) {
if (!debug_logging_allowed())
GTEST_SKIP() << "seccomp logging disabled in this build";
std::string policy_path = source_path("test/seccomp.policy");
int pipefd[2];
ASSERT_EQ(pipe(pipefd), 0);
pid_t pid = fork();
ASSERT_GE(pid, 0);
if (pid == 0) {
close(pipefd[0]);
minijail_log_to_fd(pipefd[1], LOG_INFO);
ScopedMinijail j(minijail_new());
minijail_no_new_privs(j.get());
minijail_use_seccomp_filter(j.get());
minijail_log_seccomp_filter_failures(j.get());
minijail_parse_seccomp_filters(j.get(), policy_path.c_str());
minijail_enter(j.get());
_exit(0);
}
close(pipefd[1]);
std::string log_output;
char buffer[256];
ssize_t read_ret;
while ((read_ret = read(pipefd[0], buffer, sizeof(buffer))) > 0) {
log_output.append(buffer, static_cast<size_t>(read_ret));
}
close(pipefd[0]);
int status;
ASSERT_EQ(waitpid(pid, &status, 0), pid);
ASSERT_TRUE(WIFEXITED(status));
EXPECT_EQ(WEXITSTATUS(status), 0);
EXPECT_NE(log_output.find("logging seccomp filter failures"),
std::string::npos);
}
TEST(Test, minijail_preserve_fd_no_leak) {
const ScopedMinijail j(minijail_new());
char* const script = R"(
echo Hi >&1;
exec 1>&-;
read line1;
read line2;
echo "$line1$line2 and Goodbye" >&2;
exit 42;
)";
char* const argv[] = {"sh", "-c", script, nullptr};
struct rlimit limit {};
ASSERT_EQ(0, getrlimit(RLIMIT_NOFILE, &limit));
const int high_fd = static_cast<int>(limit.rlim_cur) - 1;
const int npipes = 4;
int fds[npipes][2];
// Create pipes.
for (int i = 0; i < npipes; ++i) {
ASSERT_EQ(pipe(fds[i]), 0);
}
// (b/308042314) Move a pipe to > 1024 to check for a crash.
ASSERT_FALSE(minijail_fd_is_open(high_fd)) << "high_fd is already in use";
ASSERT_EQ(dup2(fds[3][1], high_fd), high_fd) << strerror(errno);
EXPECT_EQ(close(fds[3][1]), 0);
fds[3][1] = high_fd;
// All pipes are output pipes except for the first one which is used as
// input pipe.
std::swap(fds[0][0], fds[0][1]);
for (int i = 0; i < npipes; ++i) {
const int fd = fds[i][1];
minijail_preserve_fd(j.get(), fd, i);
}
minijail_close_open_fds(j.get());
EXPECT_EQ(minijail_run_no_preload(j.get(), kShellPath, argv), 0);
// Close unused end of pipes.
for (int i = 0; i < npipes; ++i) {
const int fd = fds[i][1];
ASSERT_EQ(close(fd), 0);
}
const int in = fds[0][0];
const int out = fds[1][0];
const int err = fds[2][0];
char buf[PIPE_BUF];
ssize_t nbytes;
// Check that stdout pipe works.
nbytes = read(out, buf, PIPE_BUF);
ASSERT_GT(nbytes, 0);
EXPECT_EQ(std::string(buf, nbytes), "Hi\n");
// Check that the write end of stdout pipe got closed by the child process. If
// the child process kept other file descriptors connected to stdout, then the
// parent process wouldn't be able to detect that all write ends of this pipe
// are closed and it would block here.
EXPECT_EQ(read(out, buf, PIPE_BUF), 0);
ASSERT_EQ(close(out), 0);
// Check that stdin pipe works.
const std::string s = "Greetings\n";
EXPECT_EQ(write(in, s.data(), s.size()), s.size());
// Close write end of pipe connected to child's stdin. If there was another
// file descriptor connected to this write end, then the child process
// wouldn't be able to detect that this write end is closed and it would
// block.
ASSERT_EQ(close(in), 0);
// Check that child process continued and ended.
nbytes = read(err, buf, PIPE_BUF);
ASSERT_GT(nbytes, 0);
EXPECT_EQ(std::string(buf, nbytes), "Greetings and Goodbye\n");
// Check that the write end of the stderr pipe is closed when the child
// process finishes.
EXPECT_EQ(read(err, buf, PIPE_BUF), 0);
ASSERT_EQ(close(err), 0);
// Check the child process termination status.
EXPECT_EQ(minijail_wait(j.get()), 42);
}
TEST(Test, close_original_pipes_after_dup2) {
// Pipe used by child process to signal that it continued after reading from
// stdin.
int to_wait[2];
ASSERT_EQ(pipe(to_wait), 0);
const ScopedMinijail j(minijail_new());
// Ensure the child inherits a stable write fd for signaling.
const int preserved_fd = 3;
minijail_preserve_fd(j.get(), to_wait[1], preserved_fd);
char* program;
ASSERT_GT(asprintf(&program, R"(
echo Hi >&1;
echo There >&2;
exec 1>&-;
exec 2>&-;
echo ready >&%d; # Signal parent that we closed fd 1 and 2
read line1;
read line2;
echo "$line1$line2 and Goodbye" >&%d;
exit 42;
)",
preserved_fd, preserved_fd),
0);
char* const argv[] = {"sh", "-c", program, nullptr};
pid_t child_pid = -1;
int in = -1;
int out = -1;
int err = -1;
EXPECT_EQ(minijail_run_pid_pipes_no_preload(j.get(), kShellPath, argv,
&child_pid, &in, &out, &err),
0);
free(program);
// Close parent's copy of child's write end of signaling pipe.
ASSERT_EQ(close(to_wait[1]), 0);
EXPECT_GT(child_pid, 0);
EXPECT_GT(in, 0);
EXPECT_GT(out, 0);
EXPECT_GT(err, 0);
struct stat st;
ASSERT_EQ(fstat(err, &st), 0);
ino_t pipe_inode = st.st_ino;
char buf[PIPE_BUF];
ssize_t n;
// Check that stdout and stderr pipes work.
n = read(out, buf, PIPE_BUF);
ASSERT_GT(n, 0);
EXPECT_EQ(std::string(buf, n), "Hi\n");
n = read(err, buf, PIPE_BUF);
ASSERT_GT(n, 0);
EXPECT_EQ(std::string(buf, n), "There\n");
// Check that the write end of stdout pipe got closed by the child.
EXPECT_EQ(read(out, buf, PIPE_BUF), 0);
ASSERT_EQ(close(out), 0);
// Read "ready" signal from child.
n = read(to_wait[0], buf, PIPE_BUF);
ASSERT_GT(n, 0);
EXPECT_EQ(std::string(buf, n), "ready\n");
// Now verify that fd 2 is closed in the child via /proc.
// Note: we do not check read(err) == 0 here because mksh keeps the pipe
// open on a high fd internally.
auto is_fd_open_in_child = [](pid_t pid, int fd, ino_t inode) -> bool {
char path[PATH_MAX];
snprintf(path, sizeof(path), "/proc/%d/fd/%d", pid, fd);
char link_target[PATH_MAX];
ssize_t len = readlink(path, link_target, sizeof(link_target) - 1);
if (len <= 0) {
return false;
}
link_target[len] = '\0';
char expected_target[64];
snprintf(expected_target, sizeof(expected_target),
"pipe:[%lu]", (unsigned long)inode);
return strcmp(link_target, expected_target) == 0;
};
EXPECT_FALSE(is_fd_open_in_child(child_pid, 2, pipe_inode));
ASSERT_EQ(close(err), 0);
// Check that stdin pipe works.
const std::string s = "Greetings\n";
EXPECT_EQ(write(in, s.data(), s.size()), s.size());
// Close write end of pipe connected to child's stdin. If there was another
// file descriptor connected to this write end, then the child wouldn't be
// able to detect that this write end is closed and it would block.
ASSERT_EQ(close(in), 0);
// Check that child process continued and ended.
n = read(to_wait[0], buf, PIPE_BUF);
ASSERT_GT(n, 0);
EXPECT_EQ(std::string(buf, n), "Greetings and Goodbye\n");
ASSERT_EQ(close(to_wait[0]), 0);
EXPECT_EQ(minijail_wait(j.get()), 42);
}
TEST(Test, minijail_no_clobber_pipe_fd) {
const ScopedMinijail j(minijail_new());
char* const script = R"(
echo Hi >&1;
exec 1>&-;
exec 4>&-;
exec 7>&-;
read line1;
read line2;
echo "$line1$line2 and Goodbye" >&2;
exit 42;
)";
char* const argv[] = {"sh", "-c", script, nullptr};
const int npipes = 3;
int fds[npipes][2];
// Create pipes.
for (int i = 0; i < npipes; ++i) {
ASSERT_EQ(pipe(fds[i]), 0);
}
// All pipes are output pipes except for the first one which is used as
// input pipe.
std::swap(fds[0][0], fds[0][1]);
// Generate a lot of mappings to try to clobber any file descriptors generated
// by libminijail.
for (int offset = 0; offset < npipes * 3; offset += npipes) {
for (int i = 0; i < npipes; ++i) {
const int fd = fds[i][1];
minijail_preserve_fd(j.get(), fd, i + offset);
}
}
minijail_close_open_fds(j.get());
EXPECT_EQ(minijail_run_no_preload(j.get(), kShellPath, argv), 0);
// Close unused end of pipes.
for (int i = 0; i < npipes; ++i) {
const int fd = fds[i][1];
ASSERT_EQ(close(fd), 0);
}
const int in = fds[0][0];
const int out = fds[1][0];
const int err = fds[2][0];
char buf[PIPE_BUF];
ssize_t nbytes;
// Check that stdout pipe works.
nbytes = read(out, buf, PIPE_BUF);
ASSERT_GT(nbytes, 0);
EXPECT_EQ(std::string(buf, nbytes), "Hi\n");
// Check that the write end of stdout pipe got closed by the child process. If
// the child process kept other file descriptors connected to stdout, then the
// parent process wouldn't be able to detect that all write ends of this pipe
// are closed and it would block here.
EXPECT_EQ(read(out, buf, PIPE_BUF), 0);
ASSERT_EQ(close(out), 0);
// Check that stdin pipe works.
const std::string s = "Greetings\n";
EXPECT_EQ(write(in, s.data(), s.size()), s.size());
// Close write end of pipe connected to child's stdin. If there was another
// file descriptor connected to this write end, then the child process
// wouldn't be able to detect that this write end is closed and it would
// block.
ASSERT_EQ(close(in), 0);
// Check that child process continued and ended.
nbytes = read(err, buf, PIPE_BUF);
ASSERT_GT(nbytes, 0);
EXPECT_EQ(std::string(buf, nbytes), "Greetings and Goodbye\n");
// Check that the write end of the stderr pipe is closed when the child
// process finishes.
EXPECT_EQ(read(err, buf, PIPE_BUF), 0);
ASSERT_EQ(close(err), 0);
// Check the child process termination status.
EXPECT_EQ(minijail_wait(j.get()), 42);
}
TEST(Test, minijail_run_env_pid_pipes) {
// TODO(crbug.com/895875): The preload library interferes with ASan since they
// both need to use LD_PRELOAD.
// TODO(b/238743201): This test consistently breaks with code coverage
// enabled. That should be fixed.
if (kCompiledWithCoverage || running_with_asan())
GTEST_SKIP();
ScopedMinijail j(minijail_new());
set_preload_path(j.get());
char* argv[4];
argv[0] = const_cast<char*>(kCatPath);
argv[1] = NULL;
pid_t pid;
int child_stdin, child_stdout;
int mj_run_ret = minijail_run_pid_pipes(j.get(), argv[0], argv, &pid,
&child_stdin, &child_stdout, NULL);
EXPECT_EQ(mj_run_ret, 0);
char teststr[] = "test\n";
const size_t teststr_len = strlen(teststr);
ssize_t write_ret = write(child_stdin, teststr, teststr_len);
EXPECT_EQ(write_ret, static_cast<ssize_t>(teststr_len));
char buf[kBufferSize] = {};
ssize_t read_ret = read(child_stdout, buf, sizeof(buf) - 1);
EXPECT_EQ(read_ret, static_cast<ssize_t>(teststr_len));
EXPECT_STREQ(buf, teststr);
int status;
EXPECT_EQ(kill(pid, SIGTERM), 0);
EXPECT_EQ(waitpid(pid, &status, 0), pid);
ASSERT_TRUE(WIFSIGNALED(status));
EXPECT_EQ(WTERMSIG(status), SIGTERM);
argv[0] = const_cast<char*>(kShellPath);
argv[1] = "-c";
argv[2] = "echo \"${TEST_PARENT+set}|${TEST_VAR}\" >&2";
argv[3] = nullptr;
char* envp[2];
envp[0] = "TEST_VAR=test";
envp[1] = NULL;
// Set a canary env var in the parent that should not be present in the child.
ASSERT_EQ(setenv("TEST_PARENT", "test", 1 /*overwrite*/), 0);
int child_stderr;
mj_run_ret =
minijail_run_env_pid_pipes(j.get(), argv[0], argv, envp, &pid,
&child_stdin, &child_stdout, &child_stderr);
EXPECT_EQ(mj_run_ret, 0);
memset(buf, 0, sizeof(buf));
read_ret = read(child_stderr, buf, sizeof(buf) - 1);
EXPECT_GE(read_ret, 0);
EXPECT_STREQ(buf, "|test\n");
EXPECT_EQ(waitpid(pid, &status, 0), pid);
ASSERT_TRUE(WIFEXITED(status));
EXPECT_EQ(WEXITSTATUS(status), 0);
}
TEST(Test, minijail_run_fd_env_pid_pipes) {
// TODO(crbug.com/895875): The preload library interferes with ASan since they
// both need to use LD_PRELOAD.
// TODO(b/238743201): This test consistently breaks with code coverage
// enabled. That should be fixed.
if (kCompiledWithCoverage || running_with_asan())
GTEST_SKIP();
ScopedMinijail j(minijail_new());
set_preload_path(j.get());
char* argv[4];
argv[0] = const_cast<char*>(kShellPath);
argv[1] = "-c";
argv[2] = "echo \"${TEST_PARENT+set}|${TEST_VAR}\" >&2\n";
argv[3] = nullptr;
char* envp[2];
envp[0] = "TEST_VAR=test";
envp[1] = nullptr;
// Set a canary env var in the parent that should not be present in the child.
ASSERT_EQ(setenv("TEST_PARENT", "test", 1 /*overwrite*/), 0);
int elf_fd = open(const_cast<char*>(kShellPath), O_RDONLY | O_CLOEXEC);
ASSERT_NE(elf_fd, -1);
int dev_null = open("/dev/null", O_RDONLY);
ASSERT_NE(dev_null, -1);
// Create a mapping to dev_null that would clobber elf_fd if it is not
// relocated.
minijail_preserve_fd(j.get(), dev_null, elf_fd);
pid_t pid;
int child_stdin, child_stdout, child_stderr;
int mj_run_ret =
minijail_run_fd_env_pid_pipes(j.get(), elf_fd, argv, envp, &pid,
&child_stdin, &child_stdout, &child_stderr);
EXPECT_EQ(mj_run_ret, 0);
close(dev_null);
char buf[kBufferSize] = {};
ssize_t read_ret = read(child_stderr, buf, sizeof(buf) - 1);
EXPECT_GE(read_ret, 0);
EXPECT_STREQ(buf, "|test\n");
int status;
EXPECT_EQ(waitpid(pid, &status, 0), pid);
ASSERT_TRUE(WIFEXITED(status));
EXPECT_EQ(WEXITSTATUS(status), 0);
}
TEST(Test, minijail_run_env_pid_pipes_with_local_preload) {
// TODO(crbug.com/895875): The preload library interferes with ASan since they
// both need to use LD_PRELOAD.
// TODO(b/238743201): This test consistently breaks with code coverage
// enabled. That should be fixed.
if (kCompiledWithCoverage || running_with_asan())
GTEST_SKIP();
ScopedMinijail j(minijail_new());
// Use the preload library from this test build.
set_preload_path(j.get());
char* argv[4];
argv[0] = const_cast<char*>(kCatPath);
argv[1] = NULL;
pid_t pid;
int child_stdin, child_stdout;
int mj_run_ret = minijail_run_pid_pipes(j.get(), argv[0], argv, &pid,
&child_stdin, &child_stdout, NULL);
EXPECT_EQ(mj_run_ret, 0);
char teststr[] = "test\n";
const size_t teststr_len = strlen(teststr);
ssize_t write_ret = write(child_stdin, teststr, teststr_len);
EXPECT_EQ(write_ret, static_cast<ssize_t>(teststr_len));
char buf[kBufferSize] = {};
ssize_t read_ret = read(child_stdout, buf, sizeof(buf) - 1);
EXPECT_EQ(read_ret, static_cast<ssize_t>(teststr_len));
EXPECT_STREQ(buf, teststr);
int status;
EXPECT_EQ(kill(pid, SIGTERM), 0);
EXPECT_EQ(waitpid(pid, &status, 0), pid);
ASSERT_TRUE(WIFSIGNALED(status));
EXPECT_EQ(WTERMSIG(status), SIGTERM);
argv[0] = const_cast<char*>(kShellPath);
argv[1] = "-c";
argv[2] = "echo \"${TEST_PARENT+set}|${TEST_VAR}\" >&2";
argv[3] = nullptr;
char* envp[2];
envp[0] = "TEST_VAR=test";
envp[1] = NULL;
// Set a canary env var in the parent that should not be present in the child.
ASSERT_EQ(setenv("TEST_PARENT", "test", 1 /*overwrite*/), 0);
int child_stderr;
mj_run_ret =
minijail_run_env_pid_pipes(j.get(), argv[0], argv, envp, &pid,
&child_stdin, &child_stdout, &child_stderr);
EXPECT_EQ(mj_run_ret, 0);
memset(buf, 0, sizeof(buf));
read_ret = read(child_stderr, buf, sizeof(buf) - 1);
EXPECT_GE(read_ret, 0);
EXPECT_STREQ(buf, "|test\n");
EXPECT_EQ(waitpid(pid, &status, 0), pid);
ASSERT_TRUE(WIFEXITED(status));
EXPECT_EQ(WEXITSTATUS(status), 0);
}
TEST(Test, preload_clears_logging_env_var_for_child) {
if (kCompiledWithCoverage || running_with_asan())
GTEST_SKIP();
ScopedMinijail j(minijail_new());
set_preload_path(j.get());
char* argv[4];
argv[0] = const_cast<char*>(kShellPath);
argv[1] = "-c";
argv[2] = "env | grep '^__MINIJAIL_LOGGING=' || echo missing";
argv[3] = nullptr;
char* envp[2];
envp[0] = "__MINIJAIL_LOGGING=stderr";
envp[1] = nullptr;
pid_t pid;
int child_stdin, child_stdout;
int mj_run_ret =
minijail_run_env_pid_pipes(j.get(), argv[0], argv, envp, &pid,
&child_stdin, &child_stdout, nullptr);
ASSERT_EQ(mj_run_ret, 0);
ASSERT_EQ(close(child_stdin), 0);
char buf[kBufferSize] = {};
ssize_t read_ret = read(child_stdout, buf, sizeof(buf) - 1);
ASSERT_GT(read_ret, 0);
EXPECT_STREQ(buf, "missing\n");
ASSERT_EQ(close(child_stdout), 0);
int status;
EXPECT_EQ(waitpid(pid, &status, 0), pid);
ASSERT_TRUE(WIFEXITED(status));
EXPECT_EQ(WEXITSTATUS(status), 0);
}
TEST(Test, test_minijail_no_clobber_fds) {
int dev_null = open("/dev/null", O_RDONLY);
ASSERT_NE(dev_null, -1);
ScopedMinijail j(minijail_new());
// Keep stderr.
minijail_preserve_fd(j.get(), 2, 2);
// Create a lot of mappings to dev_null to possibly clobber libminijail.c fds.
for (int i = 3; i < 15; ++i) {
minijail_preserve_fd(j.get(), dev_null, i);
}
char* argv[4];
argv[0] = const_cast<char*>(kShellPath);
argv[1] = "-c";
argv[2] = "echo Hello; read line1; echo \"${line1}\" >&2";
argv[3] = nullptr;
pid_t pid;
int child_stdin;
int child_stdout;
int child_stderr;
int mj_run_ret = minijail_run_pid_pipes_no_preload(
j.get(), argv[0], argv, &pid, &child_stdin, &child_stdout, &child_stderr);
EXPECT_EQ(mj_run_ret, 0);
char buf[kBufferSize];
ssize_t read_ret = read(child_stdout, buf, sizeof(buf));
EXPECT_GE(read_ret, 0);
buf[read_ret] = '\0';
EXPECT_STREQ(buf, "Hello\n");
constexpr char to_write[] = "test in and err\n";
ssize_t write_ret = write(child_stdin, to_write, sizeof(to_write));
EXPECT_EQ(write_ret, sizeof(to_write));
read_ret = read(child_stderr, buf, sizeof(buf));
EXPECT_GE(read_ret, 0);
buf[read_ret] = '\0';
EXPECT_STREQ(buf, to_write);
int status;
waitpid(pid, &status, 0);
ASSERT_TRUE(WIFEXITED(status));
EXPECT_EQ(WEXITSTATUS(status), 0);
close(dev_null);
}
TEST(Test, test_minijail_no_fd_leaks) {
pid_t pid;
int child_stdout;
int mj_run_ret;
ssize_t read_ret;
char buf[kBufferSize];
char script[kBufferSize];
int status;
char* argv[4];
int dev_null = open("/dev/null", O_RDONLY);
ASSERT_NE(dev_null, -1);
snprintf(script, sizeof(script),
"[ -e /proc/self/fd/%d ] && echo yes || echo no", dev_null);
struct minijail* j = minijail_new();
argv[0] = const_cast<char*>(kShellPath);
argv[1] = "-c";
argv[2] = script;
argv[3] = NULL;
mj_run_ret = minijail_run_pid_pipes_no_preload(j, argv[0], argv, &pid, NULL,
&child_stdout, NULL);
EXPECT_EQ(mj_run_ret, 0);
read_ret = read(child_stdout, buf, sizeof(buf));
EXPECT_GE(read_ret, 0);
buf[read_ret] = '\0';
EXPECT_STREQ(buf, "yes\n");
waitpid(pid, &status, 0);
ASSERT_TRUE(WIFEXITED(status));