From d35fbf6bdf4377f3a15b084ff812b3ee272e5347 Mon Sep 17 00:00:00 2001
From: Daniel Mack <zonque@gmail.com>
Date: Sat, 23 Aug 2014 16:02:21 +0200
Subject: [PATCH] exec: move code executed after fork into exec_child()
This factors out one conditional branch that has grown way too big, and
makes the code more readable by using return statements rather than jump
labels.
---
src/core/execute.c | 911 +++++++++++++++++++++++++++--------------------------
1 file changed, 458 insertions(+), 453 deletions(-)
diff --git a/src/core/execute.c b/src/core/execute.c
index e683fa5e16..0a5914759f 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -1223,561 +1223,566 @@ static int build_environment(
return 0;
}
-int exec_spawn(ExecCommand *command,
- const ExecContext *context,
- const ExecParameters *exec_params,
- ExecRuntime *runtime,
- pid_t *ret) {
-
- _cleanup_strv_free_ char **files_env = NULL;
- int *fds = NULL; unsigned n_fds = 0;
- int socket_fd;
- char *line, **argv;
- pid_t pid;
- int r;
+static int exec_child(ExecCommand *command,
+ const ExecContext *context,
+ const ExecParameters *params,
+ ExecRuntime *runtime,
+ char **argv,
+ int socket_fd,
+ int *fds, unsigned n_fds,
+ char **files_env,
+ int *error) {
+
+ _cleanup_strv_free_ char **our_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;
+ const char *username = NULL, *home = NULL, *shell = NULL;
+ unsigned n_dont_close = 0;
+ int dont_close[n_fds + 3];
+ uid_t uid = (uid_t) -1;
+ gid_t gid = (gid_t) -1;
+ int i, err;
assert(command);
assert(context);
- assert(ret);
- assert(exec_params);
- assert(exec_params->fds || exec_params->n_fds <= 0);
+ assert(params);
+ assert(error);
- if (context->std_input == EXEC_INPUT_SOCKET ||
- context->std_output == EXEC_OUTPUT_SOCKET ||
- context->std_error == EXEC_OUTPUT_SOCKET) {
+ rename_process_from_path(command->path);
- if (exec_params->n_fds != 1)
- return -EINVAL;
+ /* We reset exactly these signals, since they are the
+ * only ones we set to SIG_IGN in the main daemon. All
+ * others we leave untouched because we set them to
+ * SIG_DFL or a valid handler initially, both of which
+ * will be demoted to SIG_DFL. */
+ default_signals(SIGNALS_CRASH_HANDLER,
+ SIGNALS_IGNORE, -1);
- socket_fd = exec_params->fds[0];
- } else {
- socket_fd = -1;
- fds = exec_params->fds;
- n_fds = exec_params->n_fds;
+ if (context->ignore_sigpipe)
+ ignore_signals(SIGPIPE, -1);
+
+ err = reset_signal_mask();
+ if (err < 0) {
+ *error = EXIT_SIGNAL_MASK;
+ return err;
}
- r = exec_context_load_environment(context, &files_env);
- if (r < 0) {
- log_struct_unit(LOG_ERR,
- exec_params->unit_id,
- "MESSAGE=Failed to load environment files: %s", strerror(-r),
- "ERRNO=%d", -r,
- NULL);
- return r;
+ if (params->idle_pipe)
+ do_idle_pipe_dance(params->idle_pipe);
+
+ /* Close sockets very early to make sure we don't
+ * block init reexecution because it cannot bind its
+ * sockets */
+ log_forget_fds();
+
+ if (socket_fd >= 0)
+ dont_close[n_dont_close++] = socket_fd;
+ if (n_fds > 0) {
+ memcpy(dont_close + n_dont_close, fds, sizeof(int) * n_fds);
+ n_dont_close += n_fds;
+ }
+ if (runtime) {
+ if (runtime->netns_storage_socket[0] >= 0)
+ dont_close[n_dont_close++] = runtime->netns_storage_socket[0];
+ if (runtime->netns_storage_socket[1] >= 0)
+ dont_close[n_dont_close++] = runtime->netns_storage_socket[1];
}
- argv = exec_params->argv ?: command->argv;
+ err = close_all_fds(dont_close, n_dont_close);
+ if (err < 0) {
+ *error = EXIT_FDS;
+ return err;
+ }
- line = exec_command_line(argv);
- if (!line)
- return log_oom();
+ if (!context->same_pgrp)
+ if (setsid() < 0) {
+ *error = EXIT_SETSID;
+ return -errno;
+ }
- log_struct_unit(LOG_DEBUG,
- exec_params->unit_id,
- "EXECUTABLE=%s", command->path,
- "MESSAGE=About to execute: %s", line,
- NULL);
- free(line);
+ exec_context_tty_reset(context);
+
+ if (params->confirm_spawn) {
+ char response;
+
+ err = ask_for_confirmation(&response, argv);
+ if (err == -ETIMEDOUT)
+ write_confirm_message("Confirmation question timed out, assuming positive response.\n");
+ else if (err < 0)
+ write_confirm_message("Couldn't ask confirmation question, assuming positive response: %s\n", strerror(-err));
+ else if (response == 's') {
+ write_confirm_message("Skipping execution.\n");
+ *error = EXIT_CONFIRM;
+ return -ECANCELED;
+ } else if (response == 'n') {
+ write_confirm_message("Failing execution.\n");
+ *error = 0;
+ return 0;
+ }
+ }
- pid = fork();
- if (pid < 0)
- return -errno;
+ /* If a socket is connected to STDIN/STDOUT/STDERR, we
+ * must sure to drop O_NONBLOCK */
+ if (socket_fd >= 0)
+ fd_nonblock(socket_fd, false);
- if (pid == 0) {
- _cleanup_strv_free_ char **our_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;
- const char *username = NULL, *home = NULL, *shell = NULL;
- unsigned n_dont_close = 0;
- int dont_close[n_fds + 3];
- uid_t uid = (uid_t) -1;
- gid_t gid = (gid_t) -1;
- int i, err;
-
- /* child */
-
- rename_process_from_path(command->path);
-
- /* We reset exactly these signals, since they are the
- * only ones we set to SIG_IGN in the main daemon. All
- * others we leave untouched because we set them to
- * SIG_DFL or a valid handler initially, both of which
- * will be demoted to SIG_DFL. */
- default_signals(SIGNALS_CRASH_HANDLER,
- SIGNALS_IGNORE, -1);
-
- if (context->ignore_sigpipe)
- ignore_signals(SIGPIPE, -1);
-
- err = reset_signal_mask();
+ err = setup_input(context, socket_fd, params->apply_tty_stdin);
+ if (err < 0) {
+ *error = EXIT_STDIN;
+ return err;
+ }
+
+ err = setup_output(context, STDOUT_FILENO, socket_fd, basename(command->path), params->unit_id, params->apply_tty_stdin);
+ if (err < 0) {
+ *error = EXIT_STDOUT;
+ return err;
+ }
+
+ err = setup_output(context, STDERR_FILENO, socket_fd, basename(command->path), params->unit_id, params->apply_tty_stdin);
+ if (err < 0) {
+ *error = EXIT_STDERR;
+ return err;
+ }
+
+ if (params->cgroup_path) {
+ err = cg_attach_everywhere(params->cgroup_supported, params->cgroup_path, 0);
if (err < 0) {
- r = EXIT_SIGNAL_MASK;
- goto fail_child;
+ *error = EXIT_CGROUP;
+ return err;
}
+ }
- if (exec_params->idle_pipe)
- do_idle_pipe_dance(exec_params->idle_pipe);
+ if (context->oom_score_adjust_set) {
+ char t[16];
- /* Close sockets very early to make sure we don't
- * block init reexecution because it cannot bind its
- * sockets */
- log_forget_fds();
+ snprintf(t, sizeof(t), "%i", context->oom_score_adjust);
+ char_array_0(t);
- if (socket_fd >= 0)
- dont_close[n_dont_close++] = socket_fd;
- if (n_fds > 0) {
- memcpy(dont_close + n_dont_close, fds, sizeof(int) * n_fds);
- n_dont_close += n_fds;
- }
- if (runtime) {
- if (runtime->netns_storage_socket[0] >= 0)
- dont_close[n_dont_close++] = runtime->netns_storage_socket[0];
- if (runtime->netns_storage_socket[1] >= 0)
- dont_close[n_dont_close++] = runtime->netns_storage_socket[1];
+ if (write_string_file("/proc/self/oom_score_adj", t) < 0) {
+ *error = EXIT_OOM_ADJUST;
+ return -errno;
}
+ }
- err = close_all_fds(dont_close, n_dont_close);
- if (err < 0) {
- r = EXIT_FDS;
- goto fail_child;
+ if (context->nice_set)
+ if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
+ *error = EXIT_NICE;
+ return -errno;
}
- if (!context->same_pgrp)
- if (setsid() < 0) {
- err = -errno;
- r = EXIT_SETSID;
- goto fail_child;
- }
+ if (context->cpu_sched_set) {
+ struct sched_param param = {
+ .sched_priority = context->cpu_sched_priority,
+ };
- exec_context_tty_reset(context);
+ err = sched_setscheduler(0,
+ context->cpu_sched_policy |
+ (context->cpu_sched_reset_on_fork ?
+ SCHED_RESET_ON_FORK : 0),
+ ¶m);
+ if (err < 0) {
+ *error = EXIT_SETSCHEDULER;
+ return -errno;
+ }
+ }
- if (exec_params->confirm_spawn) {
- char response;
-
- err = ask_for_confirmation(&response, argv);
- if (err == -ETIMEDOUT)
- write_confirm_message("Confirmation question timed out, assuming positive response.\n");
- else if (err < 0)
- write_confirm_message("Couldn't ask confirmation question, assuming positive response: %s\n", strerror(-err));
- else if (response == 's') {
- write_confirm_message("Skipping execution.\n");
- err = -ECANCELED;
- r = EXIT_CONFIRM;
- goto fail_child;
- } else if (response == 'n') {
- write_confirm_message("Failing execution.\n");
- err = r = 0;
- goto fail_child;
- }
+ if (context->cpuset)
+ if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) {
+ *error = EXIT_CPUAFFINITY;
+ return -errno;
}
- /* If a socket is connected to STDIN/STDOUT/STDERR, we
- * must sure to drop O_NONBLOCK */
- if (socket_fd >= 0)
- fd_nonblock(socket_fd, false);
+ if (context->ioprio_set)
+ if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
+ *error = EXIT_IOPRIO;
+ return -errno;
+ }
- err = setup_input(context, socket_fd, exec_params->apply_tty_stdin);
- if (err < 0) {
- r = EXIT_STDIN;
- goto fail_child;
+ if (context->timer_slack_nsec != NSEC_INFINITY)
+ if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {
+ *error = EXIT_TIMERSLACK;
+ return -errno;
}
- err = setup_output(context, STDOUT_FILENO, socket_fd, basename(command->path), exec_params->unit_id, exec_params->apply_tty_stdin);
- if (err < 0) {
- r = EXIT_STDOUT;
- goto fail_child;
+ if (context->personality != 0xffffffffUL)
+ if (personality(context->personality) < 0) {
+ *error = EXIT_PERSONALITY;
+ return -errno;
}
- err = setup_output(context, STDERR_FILENO, socket_fd, basename(command->path), exec_params->unit_id, exec_params->apply_tty_stdin);
+ if (context->utmp_id)
+ utmp_put_init_process(context->utmp_id, getpid(), getsid(0), context->tty_path);
+
+ if (context->user) {
+ username = context->user;
+ err = get_user_creds(&username, &uid, &gid, &home, &shell);
if (err < 0) {
- r = EXIT_STDERR;
- goto fail_child;
+ *error = EXIT_USER;
+ return err;
}
- if (exec_params->cgroup_path) {
- err = cg_attach_everywhere(exec_params->cgroup_supported, exec_params->cgroup_path, 0);
+ if (is_terminal_input(context->std_input)) {
+ err = chown_terminal(STDIN_FILENO, uid);
if (err < 0) {
- r = EXIT_CGROUP;
- goto fail_child;
+ *error = EXIT_STDIN;
+ return err;
}
}
+ }
- if (context->oom_score_adjust_set) {
- char t[16];
+#ifdef HAVE_PAM
+ if (params->cgroup_path && context->user && context->pam_name) {
+ err = cg_set_task_access(SYSTEMD_CGROUP_CONTROLLER, params->cgroup_path, 0644, uid, gid);
+ if (err < 0) {
+ *error = EXIT_CGROUP;
+ return err;
+ }
- snprintf(t, sizeof(t), "%i", context->oom_score_adjust);
- char_array_0(t);
- if (write_string_file("/proc/self/oom_score_adj", t) < 0) {
- err = -errno;
- r = EXIT_OOM_ADJUST;
- goto fail_child;
- }
+ err = cg_set_group_access(SYSTEMD_CGROUP_CONTROLLER, params->cgroup_path, 0755, uid, gid);
+ if (err < 0) {
+ *error = EXIT_CGROUP;
+ return err;
}
+ }
+#endif
- if (context->nice_set)
- if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
- err = -errno;
- r = EXIT_NICE;
- goto fail_child;
- }
+ if (!strv_isempty(context->runtime_directory) && params->runtime_prefix) {
+ char **rt;
- if (context->cpu_sched_set) {
- struct sched_param param = {
- .sched_priority = context->cpu_sched_priority,
- };
+ STRV_FOREACH(rt, context->runtime_directory) {
+ _cleanup_free_ char *p;
- r = sched_setscheduler(0,
- context->cpu_sched_policy |
- (context->cpu_sched_reset_on_fork ?
- SCHED_RESET_ON_FORK : 0),
- ¶m);
- if (r < 0) {
- err = -errno;
- r = EXIT_SETSCHEDULER;
- goto fail_child;
+ p = strjoin(params->runtime_prefix, "/", *rt, NULL);
+ if (!p) {
+ *error = EXIT_RUNTIME_DIRECTORY;
+ return -ENOMEM;
}
- }
- if (context->cpuset)
- if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) {
- err = -errno;
- r = EXIT_CPUAFFINITY;
- goto fail_child;
+ err = mkdir_safe(p, context->runtime_directory_mode, uid, gid);
+ if (err < 0) {
+ *error = EXIT_RUNTIME_DIRECTORY;
+ return err;
}
+ }
+ }
- if (context->ioprio_set)
- if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
- err = -errno;
- r = EXIT_IOPRIO;
- goto fail_child;
- }
+ if (params->apply_permissions) {
+ err = enforce_groups(context, username, gid);
+ if (err < 0) {
+ *error = EXIT_GROUP;
+ return err;
+ }
+ }
- if (context->timer_slack_nsec != NSEC_INFINITY)
- if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {
- err = -errno;
- r = EXIT_TIMERSLACK;
- goto fail_child;
- }
+ umask(context->umask);
- if (context->personality != 0xffffffffUL)
- if (personality(context->personality) < 0) {
- err = -errno;
- r = EXIT_PERSONALITY;
- goto fail_child;
- }
+#ifdef HAVE_PAM
+ if (params->apply_permissions && context->pam_name && username) {
+ err = setup_pam(context->pam_name, username, uid, context->tty_path, &pam_env, fds, n_fds);
+ if (err < 0) {
+ *error = EXIT_PAM;
+ return err;
+ }
+ }
+#endif
- if (context->utmp_id)
- utmp_put_init_process(context->utmp_id, getpid(), getsid(0), context->tty_path);
+ if (context->private_network && runtime && runtime->netns_storage_socket[0] >= 0) {
+ err = setup_netns(runtime->netns_storage_socket);
+ if (err < 0) {
+ *error = EXIT_NETWORK;
+ return err;
+ }
+ }
- if (context->user) {
- username = context->user;
- err = get_user_creds(&username, &uid, &gid, &home, &shell);
- if (err < 0) {
- r = EXIT_USER;
- goto fail_child;
- }
+ if (!strv_isempty(context->read_write_dirs) ||
+ !strv_isempty(context->read_only_dirs) ||
+ !strv_isempty(context->inaccessible_dirs) ||
+ context->mount_flags != 0 ||
+ (context->private_tmp && runtime && (runtime->tmp_dir || runtime->var_tmp_dir)) ||
+ context->private_devices ||
+ context->protect_system != PROTECT_SYSTEM_NO ||
+ context->protect_home != PROTECT_HOME_NO) {
+
+ char *tmp = NULL, *var = NULL;
+
+ /* The runtime struct only contains the parent
+ * of the private /tmp, which is
+ * non-accessible to world users. Inside of it
+ * there's a /tmp that is sticky, and that's
+ * the one we want to use here. */
+
+ if (context->private_tmp && runtime) {
+ if (runtime->tmp_dir)
+ tmp = strappenda(runtime->tmp_dir, "/tmp");
+ if (runtime->var_tmp_dir)
+ var = strappenda(runtime->var_tmp_dir, "/tmp");
+ }
- if (is_terminal_input(context->std_input)) {
- err = chown_terminal(STDIN_FILENO, uid);
- if (err < 0) {
- r = EXIT_STDIN;
- goto fail_child;
- }
- }
+ err = setup_namespace(
+ context->read_write_dirs,
+ context->read_only_dirs,
+ context->inaccessible_dirs,
+ tmp,
+ var,
+ context->private_devices,
+ context->protect_home,
+ context->protect_system,
+ context->mount_flags);
+ if (err < 0) {
+ *error = EXIT_NAMESPACE;
+ return err;
}
+ }
-#ifdef HAVE_PAM
- if (exec_params->cgroup_path && context->user && context->pam_name) {
- err = cg_set_task_access(SYSTEMD_CGROUP_CONTROLLER, exec_params->cgroup_path, 0644, uid, gid);
- if (err < 0) {
- r = EXIT_CGROUP;
- goto fail_child;
+ if (params->apply_chroot) {
+ if (context->root_directory)
+ if (chroot(context->root_directory) < 0) {
+ *error = EXIT_CHROOT;
+ return -errno;
}
+ if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
+ *error = EXIT_CHDIR;
+ return -errno;
+ }
+ } else {
+ _cleanup_free_ char *d = NULL;
- err = cg_set_group_access(SYSTEMD_CGROUP_CONTROLLER, exec_params->cgroup_path, 0755, uid, gid);
- if (err < 0) {
- r = EXIT_CGROUP;
- goto fail_child;
- }
+ if (asprintf(&d, "%s/%s",
+ context->root_directory ? context->root_directory : "",
+ context->working_directory ? context->working_directory : "") < 0) {
+ *error = EXIT_MEMORY;
+ return -ENOMEM;
}
-#endif
- if (!strv_isempty(context->runtime_directory) && exec_params->runtime_prefix) {
- char **rt;
+ if (chdir(d) < 0) {
+ *error = EXIT_CHDIR;
+ return -errno;
+ }
+ }
- STRV_FOREACH(rt, context->runtime_directory) {
- _cleanup_free_ char *p;
+ /* We repeat the fd closing here, to make sure that
+ * nothing is leaked from the PAM modules. Note that
+ * we are more aggressive this time since socket_fd
+ * and the netns fds we don#t need anymore. */
+ err = close_all_fds(fds, n_fds);
+ if (err >= 0)
+ err = shift_fds(fds, n_fds);
+ if (err >= 0)
+ err = flags_fds(fds, n_fds, context->non_blocking);
+ if (err < 0) {
+ *error = EXIT_FDS;
+ return err;
+ }
- p = strjoin(exec_params->runtime_prefix, "/", *rt, NULL);
- if (!p) {
- r = EXIT_RUNTIME_DIRECTORY;
- err = -ENOMEM;
- goto fail_child;
- }
+ if (params->apply_permissions) {
- err = mkdir_safe(p, context->runtime_directory_mode, uid, gid);
- if (err < 0) {
- r = EXIT_RUNTIME_DIRECTORY;
- goto fail_child;
- }
+ for (i = 0; i < _RLIMIT_MAX; i++) {
+ if (!context->rlimit[i])
+ continue;
+
+ if (setrlimit_closest(i, context->rlimit[i]) < 0) {
+ *error = EXIT_LIMITS;
+ return -errno;
}
}
- if (exec_params->apply_permissions) {
- err = enforce_groups(context, username, gid);
+ if (context->capability_bounding_set_drop) {
+ err = capability_bounding_set_drop(context->capability_bounding_set_drop, false);
if (err < 0) {
- r = EXIT_GROUP;
- goto fail_child;
+ *error = EXIT_CAPABILITIES;
+ return err;
}
}
- umask(context->umask);
-
-#ifdef HAVE_PAM
- if (exec_params->apply_permissions && context->pam_name && username) {
- err = setup_pam(context->pam_name, username, uid, context->tty_path, &pam_env, fds, n_fds);
+ if (context->user) {
+ err = enforce_user(context, uid);
if (err < 0) {
- r = EXIT_PAM;
- goto fail_child;
+ *error = EXIT_USER;
+ return err;
}
}
-#endif
- if (context->private_network && runtime && runtime->netns_storage_socket[0] >= 0) {
- err = setup_netns(runtime->netns_storage_socket);
- if (err < 0) {
- r = EXIT_NETWORK;
- goto fail_child;
+
+ /* PR_GET_SECUREBITS is not privileged, while
+ * PR_SET_SECUREBITS is. So to suppress
+ * potential EPERMs we'll try not to call
+ * PR_SET_SECUREBITS unless necessary. */
+ if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
+ if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
+ *error = EXIT_SECUREBITS;
+ return -errno;
+ }
+
+ if (context->capabilities)
+ if (cap_set_proc(context->capabilities) < 0) {
+ *error = EXIT_CAPABILITIES;
+ return -errno;
}
- }
- if (!strv_isempty(context->read_write_dirs) ||
- !strv_isempty(context->read_only_dirs) ||
- !strv_isempty(context->inaccessible_dirs) ||
- context->mount_flags != 0 ||
- (context->private_tmp && runtime && (runtime->tmp_dir || runtime->var_tmp_dir)) ||
- context->private_devices ||
- context->protect_system != PROTECT_SYSTEM_NO ||
- context->protect_home != PROTECT_HOME_NO) {
-
- char *tmp = NULL, *var = NULL;
-
- /* The runtime struct only contains the parent
- * of the private /tmp, which is
- * non-accessible to world users. Inside of it
- * there's a /tmp that is sticky, and that's
- * the one we want to use here. */
-
- if (context->private_tmp && runtime) {
- if (runtime->tmp_dir)
- tmp = strappenda(runtime->tmp_dir, "/tmp");
- if (runtime->var_tmp_dir)
- var = strappenda(runtime->var_tmp_dir, "/tmp");
+ if (context->no_new_privileges)
+ if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) < 0) {
+ *error = EXIT_NO_NEW_PRIVILEGES;
+ return -errno;
}
- err = setup_namespace(
- context->read_write_dirs,
- context->read_only_dirs,
- context->inaccessible_dirs,
- tmp,
- var,
- context->private_devices,
- context->protect_home,
- context->protect_system,
- context->mount_flags);
+#ifdef HAVE_SECCOMP
+ if (context->address_families_whitelist ||
+ !set_isempty(context->address_families)) {
+ err = apply_address_families(context);
if (err < 0) {
- r = EXIT_NAMESPACE;
- goto fail_child;
+ *error = EXIT_ADDRESS_FAMILIES;
+ return err;
}
}
- if (exec_params->apply_chroot) {
- if (context->root_directory)
- if (chroot(context->root_directory) < 0) {
- err = -errno;
- r = EXIT_CHROOT;
- goto fail_child;
- }
-
- if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
- err = -errno;
- r = EXIT_CHDIR;
- goto fail_child;
- }
- } else {
- _cleanup_free_ char *d = NULL;
-
- if (asprintf(&d, "%s/%s",
- context->root_directory ? context->root_directory : "",
- context->working_directory ? context->working_directory : "") < 0) {
- err = -ENOMEM;
- r = EXIT_MEMORY;
- goto fail_child;
+ if (context->syscall_whitelist ||
+ !set_isempty(context->syscall_filter) ||
+ !set_isempty(context->syscall_archs)) {
+ err = apply_seccomp(context);
+ if (err < 0) {
+ *error = EXIT_SECCOMP;
+ return err;
}
+ }
+#endif
- if (chdir(d) < 0) {
- err = -errno;
- r = EXIT_CHDIR;
- goto fail_child;
+#ifdef HAVE_SELINUX
+ if (context->selinux_context && use_selinux()) {
+ err = setexeccon(context->selinux_context);
+ if (err < 0 && !context->selinux_context_ignore) {
+ *error = EXIT_SELINUX_CONTEXT;
+ return err;
}
}
+#endif
- /* We repeat the fd closing here, to make sure that
- * nothing is leaked from the PAM modules. Note that
- * we are more aggressive this time since socket_fd
- * and the netns fds we don#t need anymore. */
- err = close_all_fds(fds, n_fds);
- if (err >= 0)
- err = shift_fds(fds, n_fds);
- if (err >= 0)
- err = flags_fds(fds, n_fds, context->non_blocking);
- if (err < 0) {
- r = EXIT_FDS;
- goto fail_child;
+#ifdef HAVE_APPARMOR
+ if (context->apparmor_profile && use_apparmor()) {
+ err = aa_change_onexec(context->apparmor_profile);
+ if (err < 0 && !context->apparmor_profile_ignore) {
+ *error = EXIT_APPARMOR_PROFILE;
+ return err;
+ }
}
+#endif
+ }
- if (exec_params->apply_permissions) {
+ err = build_environment(context, n_fds, params->watchdog_usec, home, username, shell, &our_env);
+ if (err < 0) {
+ *error = EXIT_MEMORY;
+ return err;
+ }
- for (i = 0; i < _RLIMIT_MAX; i++) {
- if (!context->rlimit[i])
- continue;
+ final_env = strv_env_merge(5,
+ params->environment,
+ our_env,
+ context->environment,
+ files_env,
+ pam_env,
+ NULL);
+ if (!final_env) {
+ *error = EXIT_MEMORY;
+ return -ENOMEM;
+ }
- if (setrlimit_closest(i, context->rlimit[i]) < 0) {
- err = -errno;
- r = EXIT_LIMITS;
- goto fail_child;
- }
- }
+ final_argv = replace_env_argv(argv, final_env);
+ if (!final_argv) {
+ *error = EXIT_MEMORY;
+ return -ENOMEM;
+ }
- if (context->capability_bounding_set_drop) {
- err = capability_bounding_set_drop(context->capability_bounding_set_drop, false);
- if (err < 0) {
- r = EXIT_CAPABILITIES;
- goto fail_child;
- }
- }
+ final_env = strv_env_clean(final_env);
- if (context->user) {
- err = enforce_user(context, uid);
- if (err < 0) {
- r = EXIT_USER;
- goto fail_child;
- }
- }
+ if (_unlikely_(log_get_max_level() >= LOG_PRI(LOG_DEBUG))) {
+ _cleanup_free_ char *line;
- /* PR_GET_SECUREBITS is not privileged, while
- * PR_SET_SECUREBITS is. So to suppress
- * potential EPERMs we'll try not to call
- * PR_SET_SECUREBITS unless necessary. */
- if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
- if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
- err = -errno;
- r = EXIT_SECUREBITS;
- goto fail_child;
- }
+ line = exec_command_line(final_argv);
+ if (line) {
+ log_open();
+ log_struct_unit(LOG_DEBUG,
+ params->unit_id,
+ "EXECUTABLE=%s", command->path,
+ "MESSAGE=Executing: %s", line,
+ NULL);
+ log_close();
+ }
+ }
+ execve(command->path, final_argv, final_env);
+ *error = EXIT_EXEC;
+ return -errno;
+}
- if (context->capabilities)
- if (cap_set_proc(context->capabilities) < 0) {
- err = -errno;
- r = EXIT_CAPABILITIES;
- goto fail_child;
- }
+int exec_spawn(ExecCommand *command,
+ const ExecContext *context,
+ const ExecParameters *params,
+ ExecRuntime *runtime,
+ pid_t *ret) {
- if (context->no_new_privileges)
- if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) < 0) {
- err = -errno;
- r = EXIT_NO_NEW_PRIVILEGES;
- goto fail_child;
- }
+ _cleanup_strv_free_ char **files_env = NULL;
+ int *fds = NULL; unsigned n_fds = 0;
+ char *line, **argv;
+ int socket_fd;
+ pid_t pid;
+ int err;
-#ifdef HAVE_SECCOMP
- if (context->address_families_whitelist ||
- !set_isempty(context->address_families)) {
- err = apply_address_families(context);
- if (err < 0) {
- r = EXIT_ADDRESS_FAMILIES;
- goto fail_child;
- }
- }
+ assert(command);
+ assert(context);
+ assert(ret);
+ assert(params);
+ assert(params->fds || params->n_fds <= 0);
- if (context->syscall_whitelist ||
- !set_isempty(context->syscall_filter) ||
- !set_isempty(context->syscall_archs)) {
- err = apply_seccomp(context);
- if (err < 0) {
- r = EXIT_SECCOMP;
- goto fail_child;
- }
- }
-#endif
+ if (context->std_input == EXEC_INPUT_SOCKET ||
+ context->std_output == EXEC_OUTPUT_SOCKET ||
+ context->std_error == EXEC_OUTPUT_SOCKET) {
-#ifdef HAVE_SELINUX
- if (context->selinux_context && use_selinux()) {
- err = setexeccon(context->selinux_context);
- if (err < 0 && !context->selinux_context_ignore) {
- r = EXIT_SELINUX_CONTEXT;
- goto fail_child;
- }
- }
-#endif
+ if (params->n_fds != 1)
+ return -EINVAL;
-#ifdef HAVE_APPARMOR
- if (context->apparmor_profile && use_apparmor()) {
- err = aa_change_onexec(context->apparmor_profile);
- if (err < 0 && !context->apparmor_profile_ignore) {
- r = EXIT_APPARMOR_PROFILE;
- goto fail_child;
- }
- }
-#endif
- }
+ socket_fd = params->fds[0];
+ } else {
+ socket_fd = -1;
+ fds = params->fds;
+ n_fds = params->n_fds;
+ }
- err = build_environment(context, n_fds, exec_params->watchdog_usec, home, username, shell, &our_env);
- if (r < 0) {
- r = EXIT_MEMORY;
- goto fail_child;
- }
+ err = exec_context_load_environment(context, &files_env);
+ if (err < 0) {
+ log_struct_unit(LOG_ERR,
+ params->unit_id,
+ "MESSAGE=Failed to load environment files: %s", strerror(-err),
+ "ERRNO=%d", -err,
+ NULL);
+ return err;
+ }
- final_env = strv_env_merge(5,
- exec_params->environment,
- our_env,
- context->environment,
- files_env,
- pam_env,
- NULL);
- if (!final_env) {
- err = -ENOMEM;
- r = EXIT_MEMORY;
- goto fail_child;
- }
+ argv = params->argv ?: command->argv;
- final_argv = replace_env_argv(argv, final_env);
- if (!final_argv) {
- err = -ENOMEM;
- r = EXIT_MEMORY;
- goto fail_child;
- }
+ line = exec_command_line(argv);
+ if (!line)
+ return log_oom();
- final_env = strv_env_clean(final_env);
-
- if (_unlikely_(log_get_max_level() >= LOG_PRI(LOG_DEBUG))) {
- line = exec_command_line(final_argv);
- if (line) {
- log_open();
- log_struct_unit(LOG_DEBUG,
- exec_params->unit_id,
- "EXECUTABLE=%s", command->path,
- "MESSAGE=Executing: %s", line,
- NULL);
- log_close();
- free(line);
- line = NULL;
- }
- }
- execve(command->path, final_argv, final_env);
- err = -errno;
- r = EXIT_EXEC;
+ log_struct_unit(LOG_DEBUG,
+ params->unit_id,
+ "EXECUTABLE=%s", command->path,
+ "MESSAGE=About to execute: %s", line,
+ NULL);
+ free(line);
+
+ pid = fork();
+ if (pid < 0)
+ return -errno;
+
+ if (pid == 0) {
+ int r;
- fail_child:
+ err = exec_child(command,
+ context,
+ params,
+ runtime,
+ argv,
+ socket_fd,
+ fds, n_fds,
+ files_env,
+ &r);
if (r != 0) {
log_open();
log_struct(LOG_ERR, MESSAGE_ID(SD_MESSAGE_SPAWN_FAILED),
@@ -1794,7 +1799,7 @@ int exec_spawn(ExecCommand *command,
}
log_struct_unit(LOG_DEBUG,
- exec_params->unit_id,
+ params->unit_id,
"MESSAGE=Forked %s as "PID_FMT,
command->path, pid,
NULL);
@@ -1804,8 +1809,8 @@ int exec_spawn(ExecCommand *command,
* outside of the cgroup) and in the parent (so that we can be
* sure that when we kill the cgroup the process will be
* killed too). */
- if (exec_params->cgroup_path)
- cg_attach(SYSTEMD_CGROUP_CONTROLLER, exec_params->cgroup_path, pid);
+ if (params->cgroup_path)
+ cg_attach(SYSTEMD_CGROUP_CONTROLLER, params->cgroup_path, pid);
exec_status_start(&command->exec_status, pid);