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

Pull userns fixes from Eric W Biederman:
 "The bulk of the changes are fixing the worst consequences of the user
  namespace design oversight in not considering what happens when one
  namespace starts off as a clone of another namespace, as happens with
  the mount namespace.

  The rest of the changes are just plain bug fixes.

  Many thanks to Andy Lutomirski for pointing out many of these issues."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  userns: Restrict when proc and sysfs can be mounted
  ipc: Restrict mounting the mqueue filesystem
  vfs: Carefully propogate mounts across user namespaces
  vfs: Add a mount flag to lock read only bind mounts
  userns:  Don't allow creation if the user is chrooted
  yama:  Better permission check for ptraceme
  pid: Handle the exit of a multi-threaded init.
  scm: Require CAP_SYS_ADMIN over the current pidns to spoof pids.

3 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/fs_struct.h b/include/linux/fs_struct.h
index 729eded4b24f..2b93a9a5a1e6 100644
--- a/include/linux/fs_struct.h
+++ b/include/linux/fs_struct.h
@@ -50,4 +50,6 @@ static inline void get_fs_root_and_pwd(struct fs_struct *fs, struct path *root,
         spin_unlock(&fs->lock);
 }
 
+extern bool current_chrooted(void);
+
 #endif /* _LINUX_FS_STRUCT_H */
diff --git a/include/linux/mount.h b/include/linux/mount.h
index d7029f4a191a..73005f9957ea 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -47,6 +47,8 @@ struct mnt_namespace;
 
 #define MNT_INTERNAL    0x4000
 
+#define MNT_LOCK_READONLY       0x400000
+
 struct vfsmount {
         struct dentry *mnt_root;        /* root of the mounted tree */
         struct super_block *mnt_sb;     /* pointer to superblock */
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h
index 4ce009324933..b6b215f13b45 100644
--- a/include/linux/user_namespace.h
+++ b/include/linux/user_namespace.h
@@ -26,6 +26,8 @@ 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;
@@ -82,4 +84,6 @@ static inline void put_user_ns(struct user_namespace *ns)
 
 #endif
 
+void update_mnt_policy(struct user_namespace *userns);
+
 #endif /* _LINUX_USER_H */