conf: use mount_fd() helper when mounting ttys

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

diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index 78f59e24a53cbf4eaac94982c5b808daf90c2816..4e0398097a9fa781bca7e61ec3209eb905e6bf72 100644 (file)
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -961,7 +961,6 @@ static int lxc_setup_ttys(struct lxc_conf *conf)
        struct lxc_rootfs *rootfs = &conf->rootfs;
        const struct lxc_tty_info *ttys = &conf->ttys;
        char *ttydir = ttys->dir;
-       char tty_source[LXC_PROC_PID_FD_LEN], tty_target[LXC_PROC_PID_FD_LEN];
 
        if (!conf->rootfs.path)
                return 0;
@@ -994,7 +993,7 @@ static int lxc_setup_ttys(struct lxc_conf *conf)
                                                       "Failed to unlink %d(%s)",
                                                       rootfs->dfd_dev, tty_name);
 
-                       if (can_use_mount_api()) {
+                       if (can_use_mount_api())
                                ret = fd_bind_mount(tty->pty, "",
                                                    PROTECT_OPATH_FILE,
                                                    PROTECT_LOOKUP_BENEATH_XDEV,
@@ -1002,17 +1001,8 @@ static int lxc_setup_ttys(struct lxc_conf *conf)
                                                    PROTECT_OPATH_FILE,
                                                    PROTECT_LOOKUP_BENEATH_XDEV, 0,
                                                    false);
-                       } else {
-                               ret = strnprintf(tty_source, sizeof(tty_source), "/proc/self/fd/%d", tty->pty);
-                               if (ret < 0)
-                                       return ret;
-
-                               ret = strnprintf(tty_target, sizeof(tty_target), "/proc/self/fd/%d", fd_to);
-                               if (ret < 0)
-                                       return ret;
-
-                               ret = mount(tty_source, tty_target, "none", MS_BIND, 0);
-                       }
+                       else
+                               ret = mount_fd(tty->pty, fd_to, "none", MS_BIND, 0);
                        if (ret < 0)
                                return log_error_errno(-errno, errno,
                                                       "Failed to bind mount \"%s\" onto \"%s\"",
@@ -1037,7 +1027,7 @@ static int lxc_setup_ttys(struct lxc_conf *conf)
                                                       "Failed to create tty mount target %d(%s)",
                                                       rootfs->dfd_dev, rootfs->buf);
 
-                       if (can_use_mount_api()) {
+                       if (can_use_mount_api())
                                ret = fd_bind_mount(tty->pty, "",
                                                    PROTECT_OPATH_FILE,
                                                    PROTECT_LOOKUP_BENEATH_XDEV,
@@ -1045,17 +1035,8 @@ static int lxc_setup_ttys(struct lxc_conf *conf)
                                                    PROTECT_OPATH_FILE,
                                                    PROTECT_LOOKUP_BENEATH, 0,
                                                    false);
-                       } else {
-                               ret = strnprintf(tty_source, sizeof(tty_source), "/proc/self/fd/%d", tty->pty);
-                               if (ret < 0)
-                                       return ret;
-
-                               ret = strnprintf(tty_target, sizeof(tty_target), "/proc/self/fd/%d", fd_to);
-                               if (ret < 0)
-                                       return ret;
-
-                               ret = mount(tty_source, tty_target, "none", MS_BIND, 0);
-                       }
+                       else
+                               ret = mount_fd(tty->pty, fd_to, "none", MS_BIND, 0);
                        if (ret < 0)
                                return log_error_errno(-errno, errno,
                                                       "Failed to bind mount \"%s\" onto \"%s\"",