[CRIU] [PATCH 2/3] ns: Set NS_ROOT namespaces after tasks are read

[Kirill Tkhai]

Namespaces are read in read_ns_with_hookups(),
when tasks are not read. So, root_item is NULL,
and NS_ROOT is not set for appropriate namespaces.

This patch fixes NS_ROOT after tasks are read. Also
it adds uts, ipc and cgroup namespaces for uniformity.

Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
---
 criu/include/namespaces.h |    1 +
 criu/namespaces.c         |   33 +++++++++++++++++++++++++++++----
 criu/pstree.c             |   17 +++++++++++++++++
 3 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/criu/include/namespaces.h b/criu/include/namespaces.h
index 2a3dc085b..05c08b52e 100644
--- a/criu/include/namespaces.h
+++ b/criu/include/namespaces.h
@@ -149,6 +149,7 @@ extern int collect_mnt_namespaces(bool for_dump);
 extern int dump_mnt_namespaces(void);
 extern int dump_namespaces(struct pstree_item *item, unsigned int ns_flags);
 extern int read_ns_with_hookups(void);
+extern int set_ns_roots(void);
 extern int prepare_namespace_before_tasks(void);
 extern int prepare_namespace(struct pstree_item *item, unsigned long clone_flags);
 
diff --git a/criu/namespaces.c b/criu/namespaces.c
index b1e65df43..a92477df0 100644
--- a/criu/namespaces.c
+++ b/criu/namespaces.c
@@ -315,7 +315,6 @@ struct ns_id *rst_new_ns_id(unsigned int id, pid_t pid,
 int rst_add_ns_id(unsigned int id, struct pstree_item *i, struct ns_desc *nd)
 {
 	pid_t pid = vpid(i);
-	int type = NS_OTHER;
 	struct ns_id *nsid;
 
 	nsid = lookup_ns_by_id(id, nd);
@@ -325,9 +324,7 @@ int rst_add_ns_id(unsigned int id, struct pstree_item *i, struct ns_desc *nd)
 		return 0;
 	}
 
-	if (i == root_item && nd != &user_ns_desc)
-		type = NS_ROOT;
-	nsid = rst_new_ns_id(id, pid, nd, type);
+	nsid = rst_new_ns_id(id, pid, nd, NS_OTHER);
 	if (nsid == NULL)
 		return -1;
 
@@ -1985,6 +1982,34 @@ int read_ns_with_hookups(void)
 	return ret;
 }
 
+static int mark_root_ns(uint32_t id, struct ns_desc *desc)
+{
+	struct ns_id *ns;
+
+	ns = lookup_ns_by_id(id, desc);
+	if (!ns) {
+		pr_err("Can't find root ns %u, %s\n", id, desc->str);
+		return -1;
+	}
+	ns->type = NS_ROOT;
+	return 0;
+}
+
+int set_ns_roots(void)
+{
+	TaskKobjIdsEntry *ids = root_item->ids;
+
+	/* Set root for all namespaces except user_ns, which is set in read_ns_with_hookups() */
+	if ((ids->has_pid_ns_id && mark_root_ns(ids->pid_ns_id, &pid_ns_desc) < 0) ||
+	    (ids->has_net_ns_id && mark_root_ns(ids->net_ns_id, &net_ns_desc) < 0) ||
+	    (ids->has_ipc_ns_id && mark_root_ns(ids->ipc_ns_id, &ipc_ns_desc) < 0) ||
+	    (ids->has_uts_ns_id && mark_root_ns(ids->uts_ns_id, &uts_ns_desc) < 0) ||
+	    (ids->has_mnt_ns_id && mark_root_ns(ids->mnt_ns_id, &mnt_ns_desc) < 0) ||
+	    (ids->has_cgroup_ns_id && mark_root_ns(ids->cgroup_ns_id, &cgroup_ns_desc) < 0))
+		return -1;
+	return 0;
+}
+
 int prepare_userns(pid_t real_pid, UsernsEntry *e)
 {
 	if (write_id_map(real_pid, e->uid_map, e->n_uid_map, "uid_map"))
diff --git a/criu/pstree.c b/criu/pstree.c
index dd40fbcee..b497e1989 100644
--- a/criu/pstree.c
+++ b/criu/pstree.c
@@ -9,6 +9,9 @@
 #include "rst-malloc.h"
 #include "common/lock.h"
 #include "namespaces.h"
+#include "cgroup.h"
+#include "ipc_ns.h"
+#include "uts_ns.h"
 #include "files.h"
 #include "tty.h"
 #include "mount.h"
@@ -488,6 +491,18 @@ static int read_pstree_ids(struct pstree_item *pi)
 		if (rst_add_ns_id(pi->ids->pid_ns_id, pi, &pid_ns_desc))
 			return -1;
 	}
+	if (pi->ids->has_ipc_ns_id) {
+		if (rst_add_ns_id(pi->ids->ipc_ns_id, pi, &ipc_ns_desc))
+			return -1;
+	}
+	if (pi->ids->has_uts_ns_id) {
+		if (rst_add_ns_id(pi->ids->uts_ns_id, pi, &uts_ns_desc))
+			return -1;
+	}
+	if (pi->ids->has_cgroup_ns_id) {
+		if (rst_add_ns_id(pi->ids->cgroup_ns_id, pi, &cgroup_ns_desc))
+			return -1;
+	}
 
 	return 0;
 }
@@ -596,6 +611,8 @@ static int read_pstree_image(pid_t *pid_max)
 			goto err;
 	}
 
+	if (ret == 0)
+		ret = set_ns_roots();
 err:
 	close_image(img);
 	return ret;