From: Serge Hallyn <serge.hallyn@ubuntu.com>
Date: Tue, 14 Oct 2014 11:04:35 +0000 (+0000)
Subject: lxc-start: don't re-try to mount rootfs if we already did so
X-Git-Tag: lxc-1.1.0.alpha3~51
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6a0c909a375a75e005b2048b2d143320678e11b9;p=thirdparty%2Flxc.git

lxc-start: don't re-try to mount rootfs if we already did so

If we are root using a user namespace and are mounting a blockdev as rootfs,
then we do this before unsharing the userns, because we are not allowed to
do it in a userns.  But after unsharing the userns, we unconditionally
retried mounting the rootfs, resulting in failure.  stop that.

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
---

diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index dc790a304..8273e6ee2 100644
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -3891,7 +3891,7 @@ void tmp_proc_unmount(struct lxc_conf *lxc_conf)
 	}
 }
 
-static void remount_all_slave(void)
+void remount_all_slave(void)
 {
 	/* walk /proc/mounts and change any shared entries to slave */
 	FILE *f = fopen("/proc/self/mountinfo", "r");
@@ -4024,6 +4024,7 @@ static bool verify_start_hooks(struct lxc_conf *conf)
 					hookname);
 			return false;
 		}
+		return true;
 	}
 
 	return true;
diff --git a/src/lxc/conf.h b/src/lxc/conf.h
index 97d9f9151..2223b2d6e 100644
--- a/src/lxc/conf.h
+++ b/src/lxc/conf.h
@@ -414,5 +414,6 @@ extern int userns_exec_1(struct lxc_conf *conf, int (*fn)(void *), void *data);
 extern int parse_mntopts(const char *mntopts, unsigned long *mntflags,
 			 char **mntdata);
 extern void tmp_proc_unmount(struct lxc_conf *lxc_conf);
+void remount_all_slave(void);
 extern void suggest_default_idmap(void);
 #endif
diff --git a/src/lxc/start.c b/src/lxc/start.c
index 6fbe81cb5..b71af3787 100644
--- a/src/lxc/start.c
+++ b/src/lxc/start.c
@@ -1074,6 +1074,7 @@ int __lxc_start(const char *name, struct lxc_conf *conf,
 				ERROR("Error unsharing mounts");
 				goto out_fini_nonet;
 			}
+			remount_all_slave();
 			if (do_rootfs_setup(conf, name, lxcpath) < 0) {
 				ERROR("Error setting up rootfs mount as root before spawn");
 				goto out_fini_nonet;