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Diffstat (limited to 'src/nspawn/nspawn.c')
-rw-r--r--src/nspawn/nspawn.c136
1 files changed, 60 insertions, 76 deletions
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index bad93a5e2b..e75cc28074 100644
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -40,7 +40,6 @@
#include <sys/un.h>
#include <sys/socket.h>
#include <linux/netlink.h>
-#include <sys/eventfd.h>
#include <net/if.h>
#include <linux/veth.h>
#include <sys/personality.h>
@@ -84,12 +83,12 @@
#include "def.h"
#include "rtnl-util.h"
#include "udev-util.h"
-#include "eventfd-util.h"
#include "blkid-util.h"
#include "gpt.h"
#include "siphash24.h"
#include "copy.h"
#include "base-filesystem.h"
+#include "barrier.h"
#ifdef HAVE_SECCOMP
#include "seccomp-util.h"
@@ -3074,12 +3073,18 @@ int main(int argc, char *argv[]) {
for (;;) {
ContainerStatus container_status;
- int eventfds[2] = { -1, -1 };
+ _barrier_destroy_ Barrier barrier = { };
struct sigaction sa = {
.sa_handler = nop_handler,
.sa_flags = SA_NOCLDSTOP,
};
+ r = barrier_init(&barrier);
+ if (r < 0) {
+ log_error("Cannot initialize IPC barrier: %s", strerror(-r));
+ goto finish;
+ }
+
/* Child can be killed before execv(), so handle SIGCHLD
* in order to interrupt parent's blocking calls and
* give it a chance to call wait() and terminate. */
@@ -3095,9 +3100,9 @@ int main(int argc, char *argv[]) {
goto finish;
}
- pid = clone_with_eventfd(SIGCHLD|CLONE_NEWNS|
- (arg_share_system ? 0 : CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS)|
- (arg_private_network ? CLONE_NEWNET : 0), eventfds);
+ pid = syscall(__NR_clone, SIGCHLD|CLONE_NEWNS|
+ (arg_share_system ? 0 : CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS)|
+ (arg_private_network ? CLONE_NEWNET : 0), NULL);
if (pid < 0) {
if (errno == EINVAL)
log_error("clone() failed, do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in): %m");
@@ -3126,6 +3131,8 @@ int main(int argc, char *argv[]) {
};
char **env_use;
+ barrier_set_role(&barrier, BARRIER_CHILD);
+
envp[n_env] = strv_find_prefix(environ, "TERM=");
if (envp[n_env])
n_env ++;
@@ -3151,26 +3158,26 @@ int main(int argc, char *argv[]) {
}
log_error("Failed to open console: %s", strerror(-k));
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
if (dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO ||
dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) {
log_error("Failed to duplicate console: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
if (setsid() < 0) {
log_error("setsid() failed: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
if (reset_audit_loginuid() < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0) {
log_error("PR_SET_PDEATHSIG failed: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
/* Mark everything as slave, so that we still
@@ -3178,113 +3185,109 @@ int main(int argc, char *argv[]) {
* propagate mounts to the real root. */
if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) {
log_error("MS_SLAVE|MS_REC failed: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
if (mount_devices(arg_directory,
root_device, root_device_rw,
home_device, home_device_rw,
srv_device, srv_device_rw) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
/* Turn directory into bind mount */
if (mount(arg_directory, arg_directory, "bind", MS_BIND|MS_REC, NULL) < 0) {
log_error("Failed to make bind mount: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
r = setup_volatile(arg_directory);
if (r < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (setup_volatile_state(arg_directory) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
r = base_filesystem_create(arg_directory);
if (r < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (arg_read_only) {
k = bind_remount_recursive(arg_directory, true);
if (k < 0) {
log_error("Failed to make tree read-only: %s", strerror(-k));
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
}
if (mount_all(arg_directory) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (copy_devnodes(arg_directory) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (setup_ptmx(arg_directory) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
dev_setup(arg_directory);
if (setup_seccomp() < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (setup_dev_console(arg_directory, console) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (setup_kmsg(arg_directory, kmsg_socket_pair[1]) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
kmsg_socket_pair[1] = safe_close(kmsg_socket_pair[1]);
if (setup_boot_id(arg_directory) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (setup_timezone(arg_directory) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (setup_resolv_conf(arg_directory) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (setup_journal(arg_directory) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (mount_binds(arg_directory, arg_bind, false) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (mount_binds(arg_directory, arg_bind_ro, true) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (mount_tmpfs(arg_directory) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if (setup_kdbus(arg_directory, kdbus_domain) < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
/* Tell the parent that we are ready, and that
* it can cgroupify us to that we lack access
* to certain devices and resources. */
- r = eventfd_send_state(eventfds[1],
- EVENTFD_CHILD_SUCCEEDED);
- eventfds[1] = safe_close(eventfds[1]);
- if (r < 0)
- goto child_fail;
+ barrier_place(&barrier);
if (chdir(arg_directory) < 0) {
log_error("chdir(%s) failed: %m", arg_directory);
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
if (mount(arg_directory, "/", NULL, MS_MOVE, NULL) < 0) {
log_error("mount(MS_MOVE) failed: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
if (chroot(".") < 0) {
log_error("chroot() failed: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
if (chdir("/") < 0) {
log_error("chdir() failed: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
umask(0022);
@@ -3294,18 +3297,18 @@ int main(int argc, char *argv[]) {
if (drop_capabilities() < 0) {
log_error("drop_capabilities() failed: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
r = change_uid_gid(&home);
if (r < 0)
- goto child_fail;
+ _exit(EXIT_FAILURE);
if ((asprintf((char**)(envp + n_env++), "HOME=%s", home ? home: "/root") < 0) ||
(asprintf((char**)(envp + n_env++), "USER=%s", arg_user ? arg_user : "root") < 0) ||
(asprintf((char**)(envp + n_env++), "LOGNAME=%s", arg_user ? arg_user : "root") < 0)) {
log_oom();
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
if (!sd_id128_equal(arg_uuid, SD_ID128_NULL)) {
@@ -3313,7 +3316,7 @@ int main(int argc, char *argv[]) {
if (asprintf((char**)(envp + n_env++), "container_uuid=%s", id128_format_as_uuid(arg_uuid, as_uuid)) < 0) {
log_oom();
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
}
@@ -3321,13 +3324,13 @@ int main(int argc, char *argv[]) {
k = fdset_cloexec(fds, false);
if (k < 0) {
log_error("Failed to unset O_CLOEXEC for file descriptors.");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
if ((asprintf((char **)(envp + n_env++), "LISTEN_FDS=%u", n_fd_passed) < 0) ||
(asprintf((char **)(envp + n_env++), "LISTEN_PID=1") < 0)) {
log_oom();
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
}
@@ -3336,12 +3339,12 @@ int main(int argc, char *argv[]) {
if (arg_personality != 0xffffffffLU) {
if (personality(arg_personality) < 0) {
log_error("personality() failed: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
} else if (secondary) {
if (personality(PER_LINUX32) < 0) {
log_error("personality() failed: %m");
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
}
@@ -3349,7 +3352,7 @@ int main(int argc, char *argv[]) {
if (arg_selinux_context)
if (setexeccon((security_context_t) arg_selinux_context) < 0) {
log_error("setexeccon(\"%s\") failed: %m", arg_selinux_context);
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
#endif
@@ -3359,7 +3362,7 @@ int main(int argc, char *argv[]) {
n = strv_env_merge(2, envp, arg_setenv);
if (!n) {
log_oom();
- goto child_fail;
+ _exit(EXIT_FAILURE);
}
env_use = n;
@@ -3367,10 +3370,8 @@ int main(int argc, char *argv[]) {
env_use = (char**) envp;
/* Wait until the parent is ready with the setup, too... */
- r = eventfd_parent_succeeded(eventfds[0]);
- eventfds[0] = safe_close(eventfds[0]);
- if (r < 0)
- goto child_fail;
+ if (!barrier_place_and_sync(&barrier))
+ _exit(EXIT_FAILURE);
if (arg_boot) {
char **a;
@@ -3399,29 +3400,15 @@ int main(int argc, char *argv[]) {
}
log_error("execv() failed: %m");
-
- child_fail:
- /* Tell the parent that the setup failed, so he
- * can clean up resources and terminate. */
- if (eventfds[1] != -1)
- eventfd_send_state(eventfds[1],
- EVENTFD_CHILD_FAILED);
_exit(EXIT_FAILURE);
}
+ barrier_set_role(&barrier, BARRIER_PARENT);
fdset_free(fds);
fds = NULL;
- /* Wait for the child event:
- * If EVENTFD_CHILD_FAILED, the child will terminate soon.
- * If EVENTFD_CHILD_SUCCEEDED, the child is reporting that
- * it is ready with all it needs to do with priviliges.
- * After we got the notification we can make the process
- * join its cgroup which might limit what it can do */
- r = eventfd_child_succeeded(eventfds[1]);
- eventfds[1] = safe_close(eventfds[1]);
-
- if (r >= 0) {
+ /* wait for child-setup to be done */
+ if (barrier_place_and_sync(&barrier)) {
int ifi = 0;
r = move_network_interfaces(pid);
@@ -3458,10 +3445,7 @@ int main(int argc, char *argv[]) {
/* Notify the child that the parent is ready with all
* its setup, and that the child can now hand over
* control to the code to run inside the container. */
- r = eventfd_send_state(eventfds[0], EVENTFD_PARENT_SUCCEEDED);
- eventfds[0] = safe_close(eventfds[0]);
- if (r < 0)
- goto finish;
+ barrier_place(&barrier);
k = process_pty(master, &mask, arg_boot ? pid : 0, SIGRTMIN+3);
if (k < 0) {
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-07-22 23:00:41 +0000