Re: [libvirt] [PATCH]lxc: don't mount dir if ownership couldn't be known

From: Chen Hanxiao <chenhanxiao(a)cn.fujitsu.com&gt; We bind mount some dir from host to guest. With userns enabled, if we couldn't know the dir's ownership, don't mount it. Signed-off-by: Chen Hanxiao <chenhanxiao(a)cn.fujitsu.com&gt; --- src/lxc/lxc_container.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c index 255c711..92d0a39 100644 --- a/src/lxc/lxc_container.c +++ b/src/lxc/lxc_container.c @@ -96,6 +96,8 @@ typedef char lxc_message_t; #define LXC_CONTINUE_MSG 'c' +#define OVERFLOWUID 65534 + typedef struct __lxc_child_argv lxc_child_argv_t; struct __lxc_child_argv { virDomainDefPtr config; @@ -1073,6 +1075,18 @@ static int lxcContainerMountFSBind(virDomainFSDefPtr fs, if (virAsprintf(&src, "%s%s", srcprefix, fs->src) < 0) goto cleanup; + if (stat(src, &st) < 0) { + virReportSystemError(errno, _("Unable to stat bind source %s"), + src); + goto cleanup; + } else { + if (OVERFLOWUID == st.st_uid || OVERFLOWUID == st.st_gid) + errno = EPERM; + virReportSystemError(errno, _("Unknown st_uid/st_gid for %s"), + fs->src); + goto cleanup; + } + if (stat(fs->dst, &st) < 0) { if (errno != ENOENT) { virReportSystemError(errno, _("Unable to stat bind target %s"),