Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull namespace changes from Eric Biederman:
 "This is an assorted mishmash of small cleanups, enhancements and bug
  fixes.

  The major theme is user namespace mount restrictions.  nsown_capable
  is killed as it encourages not thinking about details that need to be
  considered.  A very hard to hit pid namespace exiting bug was finally
  tracked and fixed.  A couple of cleanups to the basic namespace
  infrastructure.

  Finally there is an enhancement that makes per user namespace
  capabilities usable as capabilities, and an enhancement that allows
  the per userns root to nice other processes in the user namespace"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  userns:  Kill nsown_capable it makes the wrong thing easy
  capabilities: allow nice if we are privileged
  pidns: Don't have unshare(CLONE_NEWPID) imply CLONE_THREAD
  userns: Allow PR_CAPBSET_DROP in a user namespace.
  namespaces: Simplify copy_namespaces so it is clear what is going on.
  pidns: Fix hang in zap_pid_ns_processes by sending a potentially extra wakeup
  sysfs: Restrict mounting sysfs
  userns: Better restrictions on when proc and sysfs can be mounted
  vfs: Don't copy mount bind mounts of /proc/<pid>/ns/mnt between namespaces
  kernel/nsproxy.c: Improving a snippet of code.
  proc: Restrict mounting the proc filesystem
  vfs: Lock in place mounts from more privileged users

5 files changed, 4 insertions, 5 deletions

diff --git a/include/linux/capability.h b/include/linux/capability.h
index d9a4f7f40f32..a6ee1f9a5018 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -210,7 +210,6 @@ extern bool has_ns_capability_noaudit(struct task_struct *t,
                                       struct user_namespace *ns, int cap);
 extern bool capable(int cap);
 extern bool ns_capable(struct user_namespace *ns, int cap);
-extern bool nsown_capable(int cap);
 extern bool inode_capable(const struct inode *inode, int cap);
 extern bool file_ns_capable(const struct file *file, struct user_namespace *ns, int cap);
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 3b4cd8296e41..529d8711baba 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1900,6 +1900,7 @@ extern int vfs_ustat(dev_t, struct kstatfs *);
 extern int freeze_super(struct super_block *super);
 extern int thaw_super(struct super_block *super);
 extern bool our_mnt(struct vfsmount *mnt);
+extern bool fs_fully_visible(struct file_system_type *);
 
 extern int current_umask(void);
 
diff --git a/include/linux/kobject_ns.h b/include/linux/kobject_ns.h
index f66b065a8b5f..df32d2508290 100644
--- a/include/linux/kobject_ns.h
+++ b/include/linux/kobject_ns.h
@@ -39,6 +39,7 @@ enum kobj_ns_type {
  */
 struct kobj_ns_type_operations {
         enum kobj_ns_type type;
+        bool (*current_may_mount)(void);
         void *(*grab_current_ns)(void);
         const void *(*netlink_ns)(struct sock *sk);
         const void *(*initial_ns)(void);
@@ -50,6 +51,7 @@ int kobj_ns_type_registered(enum kobj_ns_type type);
 const struct kobj_ns_type_operations *kobj_child_ns_ops(struct kobject *parent);
 const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj);
 
+bool kobj_ns_current_may_mount(enum kobj_ns_type type);
 void *kobj_ns_grab_current(enum kobj_ns_type type);
 const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk);
 const void *kobj_ns_initial(enum kobj_ns_type type);
diff --git a/include/linux/mount.h b/include/linux/mount.h
index 73005f9957ea..38cd98f112a0 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -48,6 +48,7 @@ struct mnt_namespace;
 #define MNT_INTERNAL    0x4000
 
 #define MNT_LOCK_READONLY       0x400000
+#define MNT_LOCKED              0x800000
 
 struct vfsmount {
         struct dentry *mnt_root;        /* root of the mounted tree */
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h
index 14105c26a836..4db29859464f 100644
--- a/include/linux/user_namespace.h
+++ b/include/linux/user_namespace.h
@@ -27,8 +27,6 @@ struct user_namespace {
         kuid_t                  owner;
         kgid_t                  group;
         unsigned int            proc_inum;
-        bool                    may_mount_sysfs;
-        bool                    may_mount_proc;
 };
 
 extern struct user_namespace init_user_ns;
@@ -85,6 +83,4 @@ static inline void put_user_ns(struct user_namespace *ns)
 
 #endif
 
-void update_mnt_policy(struct user_namespace *userns);
-
 #endif /* _LINUX_USER_H */