chiark / gitweb /
udevd: add pid to kmsg logs
[elogind.git] / udev / udevd.c
index 1bde8f4a746d19b719d71289137e308e5721ae2f..ad2ca3b4d24beababe283e00c26c5cae6f04870b 100644 (file)
@@ -34,6 +34,7 @@
 #include <sys/time.h>
 #include <sys/prctl.h>
 #include <sys/socket.h>
+#include <sys/un.h>
 #include <sys/signalfd.h>
 #include <sys/select.h>
 #include <sys/poll.h>
@@ -41,6 +42,7 @@
 #include <sys/stat.h>
 #include <sys/ioctl.h>
 #include <sys/inotify.h>
+#include <sys/utsname.h>
 
 #include "udev.h"
 
@@ -68,7 +70,6 @@ static void log_fn(struct udev *udev, int priority,
        }
 }
 
-static bool debug_trace;
 static struct udev_rules *rules;
 static struct udev_queue_export *udev_queue_export;
 static struct udev_ctrl *udev_ctrl;
@@ -77,8 +78,9 @@ static int worker_watch[2];
 static pid_t settle_pid;
 static bool stop_exec_queue;
 static bool reload_config;
-static int max_childs;
-static int childs;
+static int children;
+static int children_max;
+static int exec_delay;
 static sigset_t orig_sigmask;
 static struct udev_list_node event_list;
 static struct udev_list_node worker_list;
@@ -204,7 +206,7 @@ static void worker_unref(struct worker *worker)
 
        udev_list_node_remove(&worker->node);
        udev_monitor_unref(worker->monitor);
-       childs--;
+       children--;
        info(worker->udev, "worker [%u] cleaned up\n", worker->pid);
        free(worker);
 }
@@ -225,8 +227,10 @@ static void worker_new(struct event *event)
        udev_monitor_enable_receiving(worker_monitor);
 
        worker = calloc(1, sizeof(struct worker));
-       if (worker == NULL)
+       if (worker == NULL) {
+               udev_monitor_unref(worker_monitor);
                return;
+       }
        /* worker + event reference */
        worker->refcount = 2;
        worker->udev = event->udev;
@@ -285,6 +289,9 @@ static void worker_new(struct event *event)
                        /* set timeout to prevent hanging processes */
                        alarm(UDEV_EVENT_TIMEOUT);
 
+                       if (exec_delay > 0)
+                               udev_event->exec_delay = exec_delay;
+
                        /* apply rules, create node, symlinks */
                        err = udev_event_execute_rules(udev_event, rules);
 
@@ -354,7 +361,7 @@ static void worker_new(struct event *event)
                worker->event = event;
                event->state = EVENT_RUNNING;
                udev_list_node_append(&worker->node, &worker_list);
-               childs++;
+               children++;
                info(event->udev, "seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
                break;
        }
@@ -385,8 +392,9 @@ static void event_run(struct event *event, bool force)
                return;
        }
 
-       if (!force && childs >= max_childs) {
-               info(event->udev, "maximum number (%i) of childs reached\n", childs);
+       if (!force && children >= children_max) {
+               if (children_max > 1)
+                       info(event->udev, "maximum number (%i) of children reached\n", children);
                return;
        }
 
@@ -394,13 +402,13 @@ static void event_run(struct event *event, bool force)
        worker_new(event);
 }
 
-static void event_queue_insert(struct udev_device *dev)
+static int event_queue_insert(struct udev_device *dev)
 {
        struct event *event;
 
        event = calloc(1, sizeof(struct event));
        if (event == NULL)
-               return;
+               return -1;
 
        event->udev = udev_device_get_udev(dev);
        event->dev = dev;
@@ -421,8 +429,10 @@ static void event_queue_insert(struct udev_device *dev)
        /* run all events with a timeout set immediately */
        if (udev_device_get_timeout(dev) > 0) {
                event_run(event, true);
-               return;
+               return 0;
        }
+
+       return 0;
 }
 
 static void worker_kill(struct udev *udev, int retain)
@@ -430,10 +440,10 @@ static void worker_kill(struct udev *udev, int retain)
        struct udev_list_node *loop;
        int max;
 
-       if (childs <= retain)
+       if (children <= retain)
                return;
 
-       max = childs - retain;
+       max = children - retain;
 
        udev_list_node_foreach(loop, &worker_list) {
                struct worker *worker = node_to_worker(loop);
@@ -535,7 +545,7 @@ static void events_start(struct udev *udev)
 
 static void worker_returned(void)
 {
-       while (1) {
+       for (;;) {
                struct worker_message msg;
                ssize_t size;
                struct udev_list_node *loop;
@@ -624,10 +634,10 @@ static void handle_ctrl_msg(struct udev_ctrl *uctrl)
                worker_kill(udev, 0);
        }
 
-       i = udev_ctrl_get_set_max_childs(ctrl_msg);
+       i = udev_ctrl_get_set_children_max(ctrl_msg);
        if (i >= 0) {
-               info(udev, "udevd message (SET_MAX_CHILDS) received, max_childs=%i\n", i);
-               max_childs = i;
+               info(udev, "udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
+               children_max = i;
        }
 
        settle_pid = udev_ctrl_get_settle(ctrl_msg);
@@ -708,7 +718,7 @@ static void handle_signal(struct udev *udev, int signo)
                udev_exit = true;
                break;
        case SIGCHLD:
-               while (1) {
+               for (;;) {
                        pid_t pid;
                        int status;
                        struct udev_list_node *loop, *tmp;
@@ -745,6 +755,72 @@ static void handle_signal(struct udev *udev, int signo)
        }
 }
 
+static void static_dev_create_from_modules(struct udev *udev)
+{
+       struct utsname kernel;
+       char modules[UTIL_PATH_SIZE];
+       char buf[4096];
+       FILE *f;
+
+       uname(&kernel);
+       util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
+       f = fopen(modules, "r");
+       if (f == NULL)
+               return;
+
+       while (fgets(buf, sizeof(buf), f) != NULL) {
+               char *s;
+               const char *modname;
+               const char *devname;
+               const char *devno;
+               int maj, min;
+               char type;
+               mode_t mode;
+               char filename[UTIL_PATH_SIZE];
+
+               if (buf[0] == '#')
+                       continue;
+
+               modname = buf;
+               s = strchr(modname, ' ');
+               if (s == NULL)
+                       continue;
+               s[0] = '\0';
+
+               devname = &s[1];
+               s = strchr(devname, ' ');
+               if (s == NULL)
+                       continue;
+               s[0] = '\0';
+
+               devno = &s[1];
+               s = strchr(devno, ' ');
+               if (s == NULL)
+                       s = strchr(devno, '\n');
+               if (s != NULL)
+                       s[0] = '\0';
+               if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
+                       continue;
+
+               if (type == 'c')
+                       mode = 0600 | S_IFCHR;
+               else if (type == 'b')
+                       mode = 0600 | S_IFBLK;
+               else
+                       continue;
+
+               util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/", devname, NULL);
+               util_create_path(udev, filename);
+               udev_selinux_setfscreatecon(udev, filename, mode);
+               info(udev, "mknod '%s' %c%u:%u\n", filename, type, maj, min);
+               if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
+                       utimensat(AT_FDCWD, filename, NULL, 0);
+               udev_selinux_resetfscreatecon(udev);
+       }
+
+       fclose(f);
+}
+
 static int copy_dir(struct udev *udev, DIR *dir_from, DIR *dir_to, int maxdepth)
 {
        struct dirent *dent;
@@ -808,7 +884,7 @@ static int copy_dir(struct udev *udev, DIR *dir_from, DIR *dir_to, int maxdepth)
        return 0;
 }
 
-static void prepare_dev(struct udev *udev)
+static void static_dev_create_links(struct udev *udev, DIR *dir)
 {
        struct stdlinks {
                const char *link;
@@ -816,34 +892,48 @@ static void prepare_dev(struct udev *udev)
        };
        static const struct stdlinks stdlinks[] = {
                { "core", "/proc/kcore" },
-               { "fd", "/proc/fd" },
+               { "fd", "/proc/self/fd" },
                { "stdin", "/proc/self/fd/0" },
                { "stdout", "/proc/self/fd/1" },
                { "stderr", "/proc/self/fd/2" },
        };
        unsigned int i;
-       DIR *dir_from, *dir_to;
 
-       dir_to = opendir(udev_get_dev_path(udev));
-       if (dir_to == NULL)
-               return;
-
-       /* create standard symlinks to /proc */
        for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
-               udev_selinux_setfscreateconat(udev, dirfd(dir_to), stdlinks[i].link, S_IFLNK);
-               if (symlinkat(stdlinks[i].target, dirfd(dir_to), stdlinks[i].link) < 0 && errno == EEXIST)
-                       utimensat(dirfd(dir_to), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
-               udev_selinux_resetfscreatecon(udev);
+               struct stat sb;
+
+               if (stat(stdlinks[i].target, &sb) == 0) {
+                       udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
+                       if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
+                               utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
+                       udev_selinux_resetfscreatecon(udev);
+               }
        }
+}
+
+static void static_dev_create_from_devices(struct udev *udev, DIR *dir)
+{
+       DIR *dir_from;
 
-       /* copy content from /lib/udev/devices to /dev */
        dir_from = opendir(LIBEXECDIR "/devices");
-       if (dir_from != NULL) {
-               copy_dir(udev, dir_from, dir_to, 8);
-               closedir(dir_from);
-       }
+       if (dir_from == NULL)
+               return;
+       copy_dir(udev, dir_from, dir, 8);
+       closedir(dir_from);
+}
+
+static void static_dev_create(struct udev *udev)
+{
+       DIR *dir;
 
-       closedir(dir_to);
+       dir = opendir(udev_get_dev_path(udev));
+       if (dir == NULL)
+               return;
+
+       static_dev_create_links(udev, dir);
+       static_dev_create_from_devices(udev, dir);
+
+       closedir(dir);
 }
 
 static int mem_size_mb(void)
@@ -869,22 +959,99 @@ static int mem_size_mb(void)
        return memsize;
 }
 
+static int init_notify(const char *state)
+{
+       int fd = -1, r;
+       struct msghdr msghdr;
+       struct iovec iovec;
+       struct ucred *ucred;
+       union {
+               struct sockaddr sa;
+               struct sockaddr_un un;
+       } sockaddr;
+       union {
+               struct cmsghdr cmsghdr;
+               uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
+       } control;
+       const char *e;
+
+       if (!(e = getenv("NOTIFY_SOCKET"))) {
+               r = 0;
+               goto finish;
+       }
+
+       /* Must be an abstract socket, or an absolute path */
+       if ((e[0] != '@' && e[0] != '/') || e[1] == 0) {
+               r = -EINVAL;
+               goto finish;
+       }
+
+       if ((fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) {
+               r = -errno;
+               goto finish;
+       }
+
+       memset(&sockaddr, 0, sizeof(sockaddr));
+       sockaddr.sa.sa_family = AF_UNIX;
+       strncpy(sockaddr.un.sun_path, e, sizeof(sockaddr.un.sun_path));
+
+       if (sockaddr.un.sun_path[0] == '@')
+               sockaddr.un.sun_path[0] = 0;
+
+       memset(&iovec, 0, sizeof(iovec));
+       iovec.iov_base = (char*) state;
+       iovec.iov_len = strlen(state);
+
+       memset(&control, 0, sizeof(control));
+       control.cmsghdr.cmsg_level = SOL_SOCKET;
+       control.cmsghdr.cmsg_type = SCM_CREDENTIALS;
+       control.cmsghdr.cmsg_len = CMSG_LEN(sizeof(struct ucred));
+
+       ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
+       ucred->pid = getpid();
+       ucred->uid = getuid();
+       ucred->gid = getgid();
+
+       memset(&msghdr, 0, sizeof(msghdr));
+       msghdr.msg_name = &sockaddr;
+       msghdr.msg_namelen = sizeof(sa_family_t) + strlen(e);
+       if (msghdr.msg_namelen > sizeof(struct sockaddr_un))
+               msghdr.msg_namelen = sizeof(struct sockaddr_un);
+       msghdr.msg_iov = &iovec;
+       msghdr.msg_iovlen = 1;
+       msghdr.msg_control = &control;
+       msghdr.msg_controllen = control.cmsghdr.cmsg_len;
+
+       if (sendmsg(fd, &msghdr, MSG_NOSIGNAL) < 0) {
+               r = -errno;
+               goto finish;
+       }
+
+       r = 0;
+
+finish:
+       if (fd >= 0)
+               close(fd);
+
+       return r;
+}
+
 int main(int argc, char *argv[])
 {
        struct udev *udev;
        int fd;
        FILE *f;
        sigset_t mask;
-       const char *value;
        int daemonize = false;
        int resolve_names = 1;
        static const struct option options[] = {
                { "daemon", no_argument, NULL, 'd' },
-               { "debug-trace", no_argument, NULL, 't' },
                { "debug", no_argument, NULL, 'D' },
+               { "children-max", required_argument, NULL, 'c' },
+               { "exec-delay", required_argument, NULL, 'e' },
+               { "resolve-names", required_argument, NULL, 'N' },
                { "help", no_argument, NULL, 'h' },
                { "version", no_argument, NULL, 'V' },
-               { "resolve-names", required_argument, NULL, 'N' },
                {}
        };
        int rc = 1;
@@ -898,10 +1065,10 @@ int main(int argc, char *argv[])
        info(udev, "version %s\n", VERSION);
        udev_selinux_init(udev);
 
-       while (1) {
+       for (;;) {
                int option;
 
-               option = getopt_long(argc, argv, "dDthV", options, NULL);
+               option = getopt_long(argc, argv, "c:deDthV", options, NULL);
                if (option == -1)
                        break;
 
@@ -909,8 +1076,11 @@ int main(int argc, char *argv[])
                case 'd':
                        daemonize = true;
                        break;
-               case 't':
-                       debug_trace = true;
+               case 'c':
+                       children_max = strtoul(optarg, NULL, 0);
+                       break;
+               case 'e':
+                       exec_delay = strtoul(optarg, NULL, 0);
                        break;
                case 'D':
                        debug = true;
@@ -931,8 +1101,15 @@ int main(int argc, char *argv[])
                        }
                        break;
                case 'h':
-                       printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] "
-                              "[--resolve-names=early|late|never] [--version]\n");
+                       printf("Usage: udevd OPTIONS\n"
+                              "  --daemon\n"
+                              "  --debug\n"
+                              "  --children-max=<maximum number of workers>\n"
+                              "  --exec-delay=<seconds to wait before executing RUN=>\n"
+                              "  --resolve-names=early|late|never\n" 
+                              "  --version\n"
+                              "  --help\n"
+                              "\n");
                        goto exit;
                case 'V':
                        printf("%s\n", VERSION);
@@ -942,13 +1119,51 @@ int main(int argc, char *argv[])
                }
        }
 
+       /*
+        * read the kernel commandline, in case we need to get into debug mode
+        *   udev.log-priority=<level>              syslog priority
+        *   udev.children-max=<number of workers>  events are fully serialized if set to 1
+        *
+        */
+       f = fopen("/proc/cmdline", "r");
+       if (f != NULL) {
+               char cmdline[4096];
+
+               if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
+                       char *pos;
+
+                       pos = strstr(cmdline, "udev.log-priority=");
+                       if (pos != NULL) {
+                               pos += strlen("udev.log-priority=");
+                               udev_set_log_priority(udev, util_log_priority(pos));
+                       }
+
+                       pos = strstr(cmdline, "udev.children-max=");
+                       if (pos != NULL) {
+                               pos += strlen("udev.children-max=");
+                               children_max = strtoul(pos, NULL, 0);
+                       }
+
+                       pos = strstr(cmdline, "udev.exec-delay=");
+                       if (pos != NULL) {
+                               pos += strlen("udev.exec-delay=");
+                               exec_delay = strtoul(pos, NULL, 0);
+                       }
+               }
+               fclose(f);
+       }
+
        if (getuid() != 0) {
                fprintf(stderr, "root privileges required\n");
                err(udev, "root privileges required\n");
                goto exit;
        }
 
-       /* make sure std{in,out,err} fd's are in a sane state */
+       /* set umask before creating any file/directory */
+       chdir("/");
+       umask(022);
+
+       /* before opening new files, make sure std{in,out,err} fds are in a sane state */
        fd = open("/dev/null", O_RDWR);
        if (fd < 0) {
                fprintf(stderr, "cannot open /dev/null\n");
@@ -959,9 +1174,6 @@ int main(int argc, char *argv[])
        if (write(STDERR_FILENO, 0, 0) < 0)
                dup2(fd, STDERR_FILENO);
 
-       prepare_dev(udev);
-
-       /* init control socket, bind() ensures, that only one udevd instance is running */
        udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
        if (udev_ctrl == NULL) {
                fprintf(stderr, "error initializing control socket");
@@ -1052,6 +1264,14 @@ int main(int argc, char *argv[])
                goto exit;
        }
 
+       if (!debug) {
+               dup2(fd, STDIN_FILENO);
+               dup2(fd, STDOUT_FILENO);
+               dup2(fd, STDERR_FILENO);
+       }
+       if (fd > STDERR_FILENO)
+               close(fd);
+
        if (daemonize) {
                pid_t pid;
 
@@ -1067,30 +1287,21 @@ int main(int argc, char *argv[])
                        rc = 0;
                        goto exit;
                }
+       } else {
+               init_notify("READY=1");
        }
 
+       /* set scheduling priority for the main daemon process */
+       setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
+
+       setsid();
+
        f = fopen("/dev/kmsg", "w");
        if (f != NULL) {
-               fprintf(f, "<6>udev: starting version " VERSION "\n");
+               fprintf(f, "<6>udev[%u]: starting version " VERSION "\n", getpid());
                fclose(f);
        }
 
-       /* redirect std{out,err} */
-       if (!debug && !debug_trace) {
-               dup2(fd, STDIN_FILENO);
-               dup2(fd, STDOUT_FILENO);
-               dup2(fd, STDERR_FILENO);
-       }
-       if (fd > STDERR_FILENO)
-               close(fd);
-
-       /* set scheduling priority for the daemon */
-       setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
-
-       chdir("/");
-       umask(022);
-       setsid();
-
        /* OOM_DISABLE == -17 */
        fd = open("/proc/self/oom_adj", O_RDWR);
        if (fd < 0) {
@@ -1100,23 +1311,20 @@ int main(int argc, char *argv[])
                close(fd);
        }
 
-       /* in trace mode run one event after the other */
-       if (debug_trace) {
-               max_childs = 1;
-       } else {
+       if (children_max <= 0) {
                int memsize = mem_size_mb();
 
+               /* set value depending on the amount of RAM */
                if (memsize > 0)
-                       max_childs = 128 + (memsize / 8);
+                       children_max = 128 + (memsize / 8);
                else
-                       max_childs = 128;
+                       children_max = 128;
        }
+       info(udev, "set children_max to %u\n", children_max);
 
-       /* possibly overwrite maximum limit of executed events */
-       value = getenv("UDEVD_MAX_CHILDS");
-       if (value)
-               max_childs = strtoul(value, NULL, 10);
-       info(udev, "initialize max_childs to %u\n", max_childs);
+       static_dev_create(udev);
+       static_dev_create_from_modules(udev);
+       udev_rules_apply_static_dev_perms(rules);
 
        udev_list_init(&event_list);
        udev_list_init(&worker_list);
@@ -1126,7 +1334,7 @@ int main(int argc, char *argv[])
                int timeout;
 
                /* set timeout to kill idle workers */
-               if (udev_list_is_empty(&event_list) && childs > 2)
+               if (udev_list_is_empty(&event_list) && children > 2)
                        timeout = 3 * 1000;
                else
                        timeout = -1;
@@ -1149,9 +1357,8 @@ int main(int argc, char *argv[])
 
                        dev = udev_monitor_receive_device(monitor);
                        if (dev != NULL)
-                               event_queue_insert(dev);
-                       else
-                               udev_device_unref(dev);
+                               if (event_queue_insert(dev) < 0)
+                                       udev_device_unref(dev);
                }
 
                /* start new events */