ns proc: Add support for the uts namespace

Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c
index dcbd483e99156ce0281fe9b1715eef4060535ca7..b017181f12733a6a241da6eebcf9fcead0034b0f 100644 (file)
--- a/fs/proc/namespaces.c
+++ b/fs/proc/namespaces.c
@@ -19,6 +19,9 @@ static const struct proc_ns_operations *ns_entries[] = {
 #ifdef CONFIG_NET_NS
        &netns_operations,
 #endif
+#ifdef CONFIG_UTS_NS
+       &utsns_operations,
+#endif
 };
 
 static const struct file_operations ns_file_operations = {

diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index 62126ec6ede9f5f7ca2427e313904ff93a20888a..52aa89df8a6d4878104012017ecbfee7304d2c60 100644 (file)
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -266,6 +266,7 @@ struct proc_ns_operations {
        int (*install)(struct nsproxy *nsproxy, void *ns);
 };
 extern const struct proc_ns_operations netns_operations;
+extern const struct proc_ns_operations utsns_operations;
 
 union proc_op {
        int (*proc_get_link)(struct inode *, struct path *);

diff --git a/kernel/utsname.c b/kernel/utsname.c
index 44646179eabae8e8fd848174869f7d1782c90be8..bff131b9510a425452428005afda0acf7c979507 100644 (file)
--- a/kernel/utsname.c
+++ b/kernel/utsname.c
@@ -15,6 +15,7 @@
 #include <linux/err.h>
 #include <linux/slab.h>
 #include <linux/user_namespace.h>
+#include <linux/proc_fs.h>
 
 static struct uts_namespace *create_uts_ns(void)
 {
@@ -79,3 +80,41 @@ void free_uts_ns(struct kref *kref)
        put_user_ns(ns->user_ns);
        kfree(ns);
 }
+
+static void *utsns_get(struct task_struct *task)
+{
+       struct uts_namespace *ns = NULL;
+       struct nsproxy *nsproxy;
+
+       rcu_read_lock();
+       nsproxy = task_nsproxy(task);
+       if (nsproxy) {
+               ns = nsproxy->uts_ns;
+               get_uts_ns(ns);
+       }
+       rcu_read_unlock();
+
+       return ns;
+}
+
+static void utsns_put(void *ns)
+{
+       put_uts_ns(ns);
+}
+
+static int utsns_install(struct nsproxy *nsproxy, void *ns)
+{
+       get_uts_ns(ns);
+       put_uts_ns(nsproxy->uts_ns);
+       nsproxy->uts_ns = ns;
+       return 0;
+}
+
+const struct proc_ns_operations utsns_operations = {
+       .name           = "uts",
+       .type           = CLONE_NEWUTS,
+       .get            = utsns_get,
+       .put            = utsns_put,
+       .install        = utsns_install,
+};
+