From 98b63ed7b5612bd422f6bb52a6a7043fc2c09a1c Mon Sep 17 00:00:00 2001 From: Etienne CHAMPETIER Date: Sun, 29 May 2016 23:39:17 +0000 Subject: [PATCH] jail: ensure mounts are not MS_SHARED to avoid pivot_root() failure By default mounts are MS_PRIVATE (kernel default) but systemd decided to make it MS_SHARED by default since v188 https://github.com/systemd/systemd/commit/b3ac5f8cb98757416d8660023d6564a7c411f0a0 This patch fixes ujail on systemd distro (useful for development at least). Signed-off-by: Etienne CHAMPETIER --- jail/jail.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/jail/jail.c b/jail/jail.c index b3f27d3..e425254 100644 --- a/jail/jail.c +++ b/jail/jail.c @@ -129,6 +129,12 @@ static int build_jail_fs(void) return -1; } + /* oldroot can't be MS_SHARED else pivot_root() fails */ + if (mount("none", "/", NULL, MS_REC|MS_PRIVATE, NULL)) { + ERROR("private mount failed %s\n", strerror(errno)); + return -1; + } + if (mount("tmpfs", jail_root, "tmpfs", MS_NOATIME, "mode=0755")) { ERROR("tmpfs mount failed %s\n", strerror(errno)); return -1; -- 2.25.1