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

Pull user namespace and namespace infrastructure changes from Eric W Biederman:
 "This set of changes starts with a few small enhnacements to the user
  namespace.  reboot support, allowing more arbitrary mappings, and
  support for mounting devpts, ramfs, tmpfs, and mqueuefs as just the
  user namespace root.

  I do my best to document that if you care about limiting your
  unprivileged users that when you have the user namespace support
  enabled you will need to enable memory control groups.

  There is a minor bug fix to prevent overflowing the stack if someone
  creates way too many user namespaces.

  The bulk of the changes are a continuation of the kuid/kgid push down
  work through the filesystems.  These changes make using uids and gids
  typesafe which ensures that these filesystems are safe to use when
  multiple user namespaces are in use.  The filesystems converted for
  3.9 are ceph, 9p, afs, ocfs2, gfs2, ncpfs, nfs, nfsd, and cifs.  The
  changes for these filesystems were a little more involved so I split
  the changes into smaller hopefully obviously correct changes.

  XFS is the only filesystem that remains.  I was hoping I could get
  that in this release so that user namespace support would be enabled
  with an allyesconfig or an allmodconfig but it looks like the xfs
  changes need another couple of days before it they are ready."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (93 commits)
  cifs: Enable building with user namespaces enabled.
  cifs: Convert struct cifs_ses to use a kuid_t and a kgid_t
  cifs: Convert struct cifs_sb_info to use kuids and kgids
  cifs: Modify struct smb_vol to use kuids and kgids
  cifs: Convert struct cifsFileInfo to use a kuid
  cifs: Convert struct cifs_fattr to use kuid and kgids
  cifs: Convert struct tcon_link to use a kuid.
  cifs: Modify struct cifs_unix_set_info_args to hold a kuid_t and a kgid_t
  cifs: Convert from a kuid before printing current_fsuid
  cifs: Use kuids and kgids SID to uid/gid mapping
  cifs: Pass GLOBAL_ROOT_UID and GLOBAL_ROOT_GID to keyring_alloc
  cifs: Use BUILD_BUG_ON to validate uids and gids are the same size
  cifs: Override unmappable incoming uids and gids
  nfsd: Enable building with user namespaces enabled.
  nfsd: Properly compare and initialize kuids and kgids
  nfsd: Store ex_anon_uid and ex_anon_gid as kuids and kgids
  nfsd: Modify nfsd4_cb_sec to use kuids and kgids
  nfsd: Handle kuids and kgids in the nfs4acl to posix_acl conversion
  nfsd: Convert nfsxdr to use kuids and kgids
  nfsd: Convert nfs3xdr to use kuids and kgids
  ...

10 files changed, 39 insertions, 33 deletions

diff --git a/include/linux/coda_psdev.h b/include/linux/coda_psdev.h
index 8031d6eef102..5b8721efa948 100644
--- a/include/linux/coda_psdev.h
+++ b/include/linux/coda_psdev.h
@@ -34,7 +34,7 @@ int venus_lookup(struct super_block *sb, struct CodaFid *fid,
 		 const char *name, int length, int *type, 
 		 struct CodaFid *resfid);
 int venus_close(struct super_block *sb, struct CodaFid *fid, int flags,
-		vuid_t uid);
+		kuid_t uid);
 int venus_open(struct super_block *sb, struct CodaFid *fid, int flags,
 	       struct file **f);
 int venus_mkdir(struct super_block *sb, struct CodaFid *dirfid, 
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index e111fa419a4e..7b8fc73810ad 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -13,6 +13,7 @@
 #define _LINUX_NFS4_H
 
 #include <linux/list.h>
+#include <linux/uidgid.h>
 #include <uapi/linux/nfs4.h>
 
 struct nfs4_ace {
@@ -20,7 +21,10 @@ struct nfs4_ace {
 	uint32_t	flag;
 	uint32_t	access_mask;
 	int		whotype;
-	uid_t		who;
+	union {
+		kuid_t	who_uid;
+		kgid_t	who_gid;
+	};
 };
 
 struct nfs4_acl {
diff --git a/include/linux/nfs_idmap.h b/include/linux/nfs_idmap.h
index 2dcef3ab58b6..0f4b79da6584 100644
--- a/include/linux/nfs_idmap.h
+++ b/include/linux/nfs_idmap.h
@@ -36,6 +36,7 @@
 #ifndef NFS_IDMAP_H
 #define NFS_IDMAP_H
 
+#include <linux/uidgid.h>
 #include <uapi/linux/nfs_idmap.h>
 
 
@@ -67,10 +68,10 @@ void nfs_fattr_init_names(struct nfs_fattr *fattr,
 void nfs_fattr_free_names(struct nfs_fattr *);
 void nfs_fattr_map_and_free_names(struct nfs_server *, struct nfs_fattr *);
 
-int nfs_map_name_to_uid(const struct nfs_server *, const char *, size_t, __u32 *);
-int nfs_map_group_to_gid(const struct nfs_server *, const char *, size_t, __u32 *);
-int nfs_map_uid_to_name(const struct nfs_server *, __u32, char *, size_t);
-int nfs_map_gid_to_group(const struct nfs_server *, __u32, char *, size_t);
+int nfs_map_name_to_uid(const struct nfs_server *, const char *, size_t, kuid_t *);
+int nfs_map_group_to_gid(const struct nfs_server *, const char *, size_t, kgid_t *);
+int nfs_map_uid_to_name(const struct nfs_server *, kuid_t, char *, size_t);
+int nfs_map_gid_to_group(const struct nfs_server *, kgid_t, char *, size_t);
 
 extern unsigned int nfs_idmap_cache_timeout;
 #endif /* NFS_IDMAP_H */
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 29adb12c7ecf..13441ddac33d 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -48,8 +48,8 @@ struct nfs_fattr {
 	unsigned int		valid;		/* which fields are valid */
 	umode_t			mode;
 	__u32			nlink;
-	__u32			uid;
-	__u32			gid;
+	kuid_t			uid;
+	kgid_t			gid;
 	dev_t			rdev;
 	__u64			size;
 	union {
diff --git a/include/linux/nfsd/export.h b/include/linux/nfsd/export.h
index 24c139288db4..7898c997dfea 100644
--- a/include/linux/nfsd/export.h
+++ b/include/linux/nfsd/export.h
@@ -49,8 +49,8 @@ struct svc_export {
 	struct auth_domain *	ex_client;
 	int			ex_flags;
 	struct path		ex_path;
-	uid_t			ex_anon_uid;
-	gid_t			ex_anon_gid;
+	kuid_t			ex_anon_uid;
+	kgid_t			ex_anon_gid;
 	int			ex_fsid;
 	unsigned char *		ex_uuid; /* 16 byte fsid */
 	struct nfsd4_fs_locations ex_fslocs;
diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h
index f25ba922baaf..58fda1c3c783 100644
--- a/include/linux/sunrpc/auth.h
+++ b/include/linux/sunrpc/auth.h
@@ -17,14 +17,15 @@
 
 #include <linux/atomic.h>
 #include <linux/rcupdate.h>
+#include <linux/uidgid.h>
 
 /* size of the nodename buffer */
 #define UNX_MAXNODENAME	32
 
 /* Work around the lack of a VFS credential */
 struct auth_cred {
-	uid_t	uid;
-	gid_t	gid;
+	kuid_t	uid;
+	kgid_t	gid;
 	struct group_info *group_info;
 	const char *principal;
 	unsigned char machine_cred : 1;
@@ -48,7 +49,7 @@ struct rpc_cred {
 	unsigned long		cr_flags;	/* various flags */
 	atomic_t		cr_count;	/* ref count */
 
-	uid_t			cr_uid;
+	kuid_t			cr_uid;
 
 	/* per-flavor data */
 };
diff --git a/include/linux/sunrpc/svcauth.h b/include/linux/sunrpc/svcauth.h
index dd74084a9799..ff374ab30839 100644
--- a/include/linux/sunrpc/svcauth.h
+++ b/include/linux/sunrpc/svcauth.h
@@ -18,8 +18,8 @@
 #include <linux/cred.h>
 
 struct svc_cred {
-	uid_t			cr_uid;
-	gid_t			cr_gid;
+	kuid_t			cr_uid;
+	kgid_t			cr_gid;
 	struct group_info	*cr_group_info;
 	u32			cr_flavor; /* pseudoflavor */
 	char			*cr_principal; /* for gss */
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h
index b9bd2e6c73cc..4ce009324933 100644
--- a/include/linux/user_namespace.h
+++ b/include/linux/user_namespace.h
@@ -21,7 +21,7 @@ struct user_namespace {
 	struct uid_gid_map	uid_map;
 	struct uid_gid_map	gid_map;
 	struct uid_gid_map	projid_map;
-	struct kref		kref;
+	atomic_t		count;
 	struct user_namespace	*parent;
 	kuid_t			owner;
 	kgid_t			group;
@@ -35,18 +35,18 @@ extern struct user_namespace init_user_ns;
 static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
 {
 	if (ns)
-		kref_get(&ns->kref);
+		atomic_inc(&ns->count);
 	return ns;
 }
 
 extern int create_user_ns(struct cred *new);
 extern int unshare_userns(unsigned long unshare_flags, struct cred **new_cred);
-extern void free_user_ns(struct kref *kref);
+extern void free_user_ns(struct user_namespace *ns);
 
 static inline void put_user_ns(struct user_namespace *ns)
 {
-	if (ns)
-		kref_put(&ns->kref, free_user_ns);
+	if (ns && atomic_dec_and_test(&ns->count))
+		free_user_ns(ns);
 }
 
 struct seq_operations;
diff --git a/include/net/9p/9p.h b/include/net/9p/9p.h
index 7184853ca360..27dfe85772b1 100644
--- a/include/net/9p/9p.h
+++ b/include/net/9p/9p.h
@@ -407,17 +407,17 @@ struct p9_wstat {
 	char *gid;
 	char *muid;
 	char *extension;	/* 9p2000.u extensions */
-	u32 n_uid;		/* 9p2000.u extensions */
-	u32 n_gid;		/* 9p2000.u extensions */
-	u32 n_muid;		/* 9p2000.u extensions */
+	kuid_t n_uid;		/* 9p2000.u extensions */
+	kgid_t n_gid;		/* 9p2000.u extensions */
+	kuid_t n_muid;		/* 9p2000.u extensions */
 };
 
 struct p9_stat_dotl {
 	u64 st_result_mask;
 	struct p9_qid qid;
 	u32 st_mode;
-	u32 st_uid;
-	u32 st_gid;
+	kuid_t st_uid;
+	kgid_t st_gid;
 	u64 st_nlink;
 	u64 st_rdev;
 	u64 st_size;
@@ -471,8 +471,8 @@ struct p9_stat_dotl {
 struct p9_iattr_dotl {
 	u32 valid;
 	u32 mode;
-	u32 uid;
-	u32 gid;
+	kuid_t uid;
+	kgid_t gid;
 	u64 size;
 	u64 atime_sec;
 	u64 atime_nsec;
diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index fc9b90b0c052..5ff70f433e87 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -187,7 +187,7 @@ struct p9_fid {
 	int mode;
 	struct p9_qid qid;
 	u32 iounit;
-	uid_t uid;
+	kuid_t uid;
 
 	void *rdir;
 
@@ -220,17 +220,17 @@ void p9_client_destroy(struct p9_client *clnt);
 void p9_client_disconnect(struct p9_client *clnt);
 void p9_client_begin_disconnect(struct p9_client *clnt);
 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
-					char *uname, u32 n_uname, char *aname);
+				char *uname, kuid_t n_uname, char *aname);
 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
 		char **wnames, int clone);
 int p9_client_open(struct p9_fid *fid, int mode);
 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
 							char *extension);
 int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, char *newname);
-int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, gid_t gid,
+int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, kgid_t gid,
 							struct p9_qid *qid);
 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
-		gid_t gid, struct p9_qid *qid);
+		kgid_t gid, struct p9_qid *qid);
 int p9_client_clunk(struct p9_fid *fid);
 int p9_client_fsync(struct p9_fid *fid, int datasync);
 int p9_client_remove(struct p9_fid *fid);
@@ -250,9 +250,9 @@ struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
 							u64 request_mask);
 
 int p9_client_mknod_dotl(struct p9_fid *oldfid, char *name, int mode,
-			dev_t rdev, gid_t gid, struct p9_qid *);
+			dev_t rdev, kgid_t gid, struct p9_qid *);
 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
-				gid_t gid, struct p9_qid *);
+				kgid_t gid, struct p9_qid *);
 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status);
 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl);
 struct p9_req_t *p9_tag_lookup(struct p9_client *, u16);