If the filesystem mounts on the host have the MS_SHARED or MS_SLAVE flag set, and a container without a rootfs is started, then any new mounts created inside the container are currently propagated into the host. In addition to mounts placed in the configuration file of the container or performed manually after startup, the automatic mounting of /proc by lxc-execute will propagate back into the host, effectively crippling the entire system. This can be prevented by setting the MS_SLAVE flag on all mounts (inside the container's own mount namespace) during startup if a rootfs is not configured.
Signed-off-by: David Ward <david.w...@ll.mit.edu> --- src/lxc/conf.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/src/lxc/conf.c b/src/lxc/conf.c index 965a0d2..6b3f318 100644 --- a/src/lxc/conf.c +++ b/src/lxc/conf.c @@ -1129,8 +1129,13 @@ static int setup_rootfs(struct lxc_conf *conf) { const struct lxc_rootfs *rootfs = &conf->rootfs; - if (!rootfs->path) + if (!rootfs->path) { + if (mount("", "/", NULL, MS_SLAVE|MS_REC, 0)) { + SYSERROR("Failed to make / rslave"); + return -1; + } return 0; + } if (access(rootfs->mount, F_OK)) { SYSERROR("failed to access to '%s', check it is present", -- 1.7.1 ------------------------------------------------------------------------------ Own the Future-Intel® Level Up Game Demo Contest 2013 Rise to greatness in Intel's independent game demo contest. Compete for recognition, cash, and the chance to get your game on Steam. $5K grand prize plus 10 genre and skill prizes. Submit your demo by 6/6/13. http://p.sf.net/sfu/intel_levelupd2d _______________________________________________ Lxc-devel mailing list Lxc-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lxc-devel