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

Pull user namespace changes from Eric Biederman:
 "This is a mostly modest set of changes to enable basic user namespace
  support.  This allows the code to code to compile with user namespaces
  enabled and removes the assumption there is only the initial user
  namespace.  Everything is converted except for the most complex of the
  filesystems: autofs4, 9p, afs, ceph, cifs, coda, fuse, gfs2, ncpfs,
  nfs, ocfs2 and xfs as those patches need a bit more review.

  The strategy is to push kuid_t and kgid_t values are far down into
  subsystems and filesystems as reasonable.  Leaving the make_kuid and
  from_kuid operations to happen at the edge of userspace, as the values
  come off the disk, and as the values come in from the network.
  Letting compile type incompatible compile errors (present when user
  namespaces are enabled) guide me to find the issues.

  The most tricky areas have been the places where we had an implicit
  union of uid and gid values and were storing them in an unsigned int.
  Those places were converted into explicit unions.  I made certain to
  handle those places with simple trivial patches.

  Out of that work I discovered we have generic interfaces for storing
  quota by projid.  I had never heard of the project identifiers before.
  Adding full user namespace support for project identifiers accounts
  for most of the code size growth in my git tree.

  Ultimately there will be work to relax privlige checks from
  "capable(FOO)" to "ns_capable(user_ns, FOO)" where it is safe allowing
  root in a user names to do those things that today we only forbid to
  non-root users because it will confuse suid root applications.

  While I was pushing kuid_t and kgid_t changes deep into the audit code
  I made a few other cleanups.  I capitalized on the fact we process
  netlink messages in the context of the message sender.  I removed
  usage of NETLINK_CRED, and started directly using current->tty.

  Some of these patches have also made it into maintainer trees, with no
  problems from identical code from different trees showing up in
  linux-next.

  After reading through all of this code I feel like I might be able to
  win a game of kernel trivial pursuit."

Fix up some fairly trivial conflicts in netfilter uid/git logging code.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (107 commits)
  userns: Convert the ufs filesystem to use kuid/kgid where appropriate
  userns: Convert the udf filesystem to use kuid/kgid where appropriate
  userns: Convert ubifs to use kuid/kgid
  userns: Convert squashfs to use kuid/kgid where appropriate
  userns: Convert reiserfs to use kuid and kgid where appropriate
  userns: Convert jfs to use kuid/kgid where appropriate
  userns: Convert jffs2 to use kuid and kgid where appropriate
  userns: Convert hpfs to use kuid and kgid where appropriate
  userns: Convert btrfs to use kuid/kgid where appropriate
  userns: Convert bfs to use kuid/kgid where appropriate
  userns: Convert affs to use kuid/kgid wherwe appropriate
  userns: On alpha modify linux_to_osf_stat to use convert from kuids and kgids
  userns: On ia64 deal with current_uid and current_gid being kuid and kgid
  userns: On ppc convert current_uid from a kuid before printing.
  userns: Convert s390 getting uid and gid system calls to use kuid and kgid
  userns: Convert s390 hypfs to use kuid and kgid where appropriate
  userns: Convert binder ipc to use kuids
  userns: Teach security_path_chown to take kuids and kgids
  userns: Add user namespace support to IMA
  userns: Convert EVM to deal with kuids and kgids in it's hmac computation
  ...

1 files changed, 130 insertions, 6 deletions

diff --git a/include/linux/quota.h b/include/linux/quota.h
index 524ede8a160a..dcd5721e626d 100644
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -181,10 +181,135 @@ enum {
 #include <linux/dqblk_v2.h>
 
 #include <linux/atomic.h>
+#include <linux/uidgid.h>
+#include <linux/projid.h>
+
+#undef USRQUOTA
+#undef GRPQUOTA
+enum quota_type {
+	USRQUOTA = 0,		/* element used for user quotas */
+	GRPQUOTA = 1,		/* element used for group quotas */
+	PRJQUOTA = 2,		/* element used for project quotas */
+};
 
 typedef __kernel_uid32_t qid_t; /* Type in which we store ids in memory */
 typedef long long qsize_t;	/* Type in which we store sizes */
 
+struct kqid {			/* Type in which we store the quota identifier */
+	union {
+		kuid_t uid;
+		kgid_t gid;
+		kprojid_t projid;
+	};
+	enum quota_type type;  /* USRQUOTA (uid) or GRPQUOTA (gid) or PRJQUOTA (projid) */
+};
+
+extern bool qid_eq(struct kqid left, struct kqid right);
+extern bool qid_lt(struct kqid left, struct kqid right);
+extern qid_t from_kqid(struct user_namespace *to, struct kqid qid);
+extern qid_t from_kqid_munged(struct user_namespace *to, struct kqid qid);
+extern bool qid_valid(struct kqid qid);
+
+/**
+ *	make_kqid - Map a user-namespace, type, qid tuple into a kqid.
+ *	@from: User namespace that the qid is in
+ *	@type: The type of quota
+ *	@qid: Quota identifier
+ *
+ *	Maps a user-namespace, type qid tuple into a kernel internal
+ *	kqid, and returns that kqid.
+ *
+ *	When there is no mapping defined for the user-namespace, type,
+ *	qid tuple an invalid kqid is returned.  Callers are expected to
+ *	test for and handle handle invalid kqids being returned.
+ *	Invalid kqids may be tested for using qid_valid().
+ */
+static inline struct kqid make_kqid(struct user_namespace *from,
+				    enum quota_type type, qid_t qid)
+{
+	struct kqid kqid;
+
+	kqid.type = type;
+	switch (type) {
+	case USRQUOTA:
+		kqid.uid = make_kuid(from, qid);
+		break;
+	case GRPQUOTA:
+		kqid.gid = make_kgid(from, qid);
+		break;
+	case PRJQUOTA:
+		kqid.projid = make_kprojid(from, qid);
+		break;
+	default:
+		BUG();
+	}
+	return kqid;
+}
+
+/**
+ *	make_kqid_invalid - Explicitly make an invalid kqid
+ *	@type: The type of quota identifier
+ *
+ *	Returns an invalid kqid with the specified type.
+ */
+static inline struct kqid make_kqid_invalid(enum quota_type type)
+{
+	struct kqid kqid;
+
+	kqid.type = type;
+	switch (type) {
+	case USRQUOTA:
+		kqid.uid = INVALID_UID;
+		break;
+	case GRPQUOTA:
+		kqid.gid = INVALID_GID;
+		break;
+	case PRJQUOTA:
+		kqid.projid = INVALID_PROJID;
+		break;
+	default:
+		BUG();
+	}
+	return kqid;
+}
+
+/**
+ *	make_kqid_uid - Make a kqid from a kuid
+ *	@uid: The kuid to make the quota identifier from
+ */
+static inline struct kqid make_kqid_uid(kuid_t uid)
+{
+	struct kqid kqid;
+	kqid.type = USRQUOTA;
+	kqid.uid = uid;
+	return kqid;
+}
+
+/**
+ *	make_kqid_gid - Make a kqid from a kgid
+ *	@gid: The kgid to make the quota identifier from
+ */
+static inline struct kqid make_kqid_gid(kgid_t gid)
+{
+	struct kqid kqid;
+	kqid.type = GRPQUOTA;
+	kqid.gid = gid;
+	return kqid;
+}
+
+/**
+ *	make_kqid_projid - Make a kqid from a projid
+ *	@projid: The kprojid to make the quota identifier from
+ */
+static inline struct kqid make_kqid_projid(kprojid_t projid)
+{
+	struct kqid kqid;
+	kqid.type = PRJQUOTA;
+	kqid.projid = projid;
+	return kqid;
+}
+
+
 extern spinlock_t dq_data_lock;
 
 /* Maximal numbers of writes for quota operation (insert/delete/update)
@@ -294,10 +419,9 @@ struct dquot {
 	atomic_t dq_count;		/* Use count */
 	wait_queue_head_t dq_wait_unused;	/* Wait queue for dquot to become unused */
 	struct super_block *dq_sb;	/* superblock this applies to */
-	unsigned int dq_id;		/* ID this applies to (uid, gid) */
+	struct kqid dq_id;		/* ID this applies to (uid, gid, projid) */
 	loff_t dq_off;			/* Offset of dquot on disk */
 	unsigned long dq_flags;		/* See DQ_* */
-	short dq_type;			/* Type of quota */
 	struct mem_dqblk dq_dqb;	/* Diskquota usage */
 };
 
@@ -336,8 +460,8 @@ struct quotactl_ops {
 	int (*quota_sync)(struct super_block *, int);
 	int (*get_info)(struct super_block *, int, struct if_dqinfo *);
 	int (*set_info)(struct super_block *, int, struct if_dqinfo *);
-	int (*get_dqblk)(struct super_block *, int, qid_t, struct fs_disk_quota *);
-	int (*set_dqblk)(struct super_block *, int, qid_t, struct fs_disk_quota *);
+	int (*get_dqblk)(struct super_block *, struct kqid, struct fs_disk_quota *);
+	int (*set_dqblk)(struct super_block *, struct kqid, struct fs_disk_quota *);
 	int (*get_xstate)(struct super_block *, struct fs_quota_stat *);
 	int (*set_xstate)(struct super_block *, unsigned int, int);
 };
@@ -386,10 +510,10 @@ static inline unsigned int dquot_generic_flag(unsigned int flags, int type)
 }
 
 #ifdef CONFIG_QUOTA_NETLINK_INTERFACE
-extern void quota_send_warning(short type, unsigned int id, dev_t dev,
+extern void quota_send_warning(struct kqid qid, dev_t dev,
 			       const char warntype);
 #else
-static inline void quota_send_warning(short type, unsigned int id, dev_t dev,
+static inline void quota_send_warning(struct kqid qid, dev_t dev,
 				      const char warntype)
 {
 	return;