conf: use mount_fd() in lxc_setup_dev_console()

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index 4e0398097a9fa781bca7e61ec3209eb905e6bf72..2f6230545573f946ac56b7abe22aa141fb7bbbd1 100644 (file)
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -1876,14 +1876,16 @@ static int lxc_bind_mount_console(const struct lxc_terminal *console,
 static int lxc_setup_dev_console(struct lxc_rootfs *rootfs,
                                 const struct lxc_terminal *console)
 {
+       __do_close int fd_console = -EBADF;
        int ret;
-       char *rootfs_path = rootfs->path ? rootfs->mount : "";
 
        /*
         * When we are asked to setup a console we remove any previous
         * /dev/console bind-mounts.
         */
        if (exists_file_at(rootfs->dfd_dev, "console")) {
+               char *rootfs_path = rootfs->path ? rootfs->mount : "";
+
                ret = strnprintf(rootfs->buf, sizeof(rootfs->buf), "%s/dev/console", rootfs_path);
                if (ret < 0)
                        return -1;
@@ -1899,23 +1901,19 @@ static int lxc_setup_dev_console(struct lxc_rootfs *rootfs,
         * For unprivileged containers autodev or automounts will already have
         * taken care of creating /dev/console.
         */
-       ret = mknodat(rootfs->dfd_dev, "console", S_IFREG | 0000, 0);
-       if (ret < 0 && errno != EEXIST)
-               return log_error_errno(-errno, errno, "Failed to create console");
+       fd_console = open_at(rootfs->dfd_dev, "console", PROTECT_OPEN | O_CREAT,
+                            PROTECT_LOOKUP_BENEATH, 0000);
+       if (fd_console < 0)
+               return syserror("Failed to create console");
 
        ret = fchmod(console->pty, 0620);
        if (ret < 0)
                return log_error_errno(-errno, errno, "Failed to set mode \"0%o\" to \"%s\"", 0620, console->name);
 
-       if (can_use_mount_api()) {
+       if (can_use_mount_api())
                ret = lxc_bind_mount_console(console, rootfs->dfd_dev, "console");
-       } else {
-               ret = strnprintf(rootfs->buf, sizeof(rootfs->buf), "%s/dev/console", rootfs_path);
-               if (ret < 0)
-                       return ret;
-
-               ret = safe_mount(console->name, rootfs->buf, "none", MS_BIND, NULL, rootfs_path);
-       }
+       else
+               ret = mount_fd(console->pty, fd_console, "none", MS_BIND, NULL);
        if (ret < 0)
                return log_error_errno(ret, errno, "Failed to mount %d(%s) on \"%s\"", console->pty, console->name, rootfs->buf);