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
  ...

5 files changed, 50 insertions, 33 deletions

diff --git a/ipc/msg.c b/ipc/msg.c
index 7385de25788a..a71af5a65abf 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -443,9 +443,12 @@ static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
                         goto out_unlock;
                 }
 
+                err = ipc_update_perm(&msqid64.msg_perm, ipcp);
+                if (err)
+                        goto out_unlock;
+
                 msq->q_qbytes = msqid64.msg_qbytes;
 
-                ipc_update_perm(&msqid64.msg_perm, ipcp);
                 msq->q_ctime = get_seconds();
                 /* sleeping receivers might be excluded by
                  * stricter permissions.
@@ -922,6 +925,7 @@ out:
 #ifdef CONFIG_PROC_FS
 static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
 {
+        struct user_namespace *user_ns = seq_user_ns(s);
         struct msg_queue *msq = it;
 
         return seq_printf(s,
@@ -933,10 +937,10 @@ static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
                         msq->q_qnum,
                         msq->q_lspid,
                         msq->q_lrpid,
-                        msq->q_perm.uid,
-                        msq->q_perm.gid,
-                        msq->q_perm.cuid,
-                        msq->q_perm.cgid,
+                        from_kuid_munged(user_ns, msq->q_perm.uid),
+                        from_kgid_munged(user_ns, msq->q_perm.gid),
+                        from_kuid_munged(user_ns, msq->q_perm.cuid),
+                        from_kgid_munged(user_ns, msq->q_perm.cgid),
                         msq->q_stime,
                         msq->q_rtime,
                         msq->q_ctime);
diff --git a/ipc/sem.c b/ipc/sem.c
index 5215a81420df..58d31f1c1eb5 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -1104,7 +1104,9 @@ static int semctl_down(struct ipc_namespace *ns, int semid,
                 freeary(ns, ipcp);
                 goto out_up;
         case IPC_SET:
-                ipc_update_perm(&semid64.sem_perm, ipcp);
+                err = ipc_update_perm(&semid64.sem_perm, ipcp);
+                if (err)
+                        goto out_unlock;
                 sma->sem_ctime = get_seconds();
                 break;
         default:
@@ -1677,6 +1679,7 @@ void exit_sem(struct task_struct *tsk)
 #ifdef CONFIG_PROC_FS
 static int sysvipc_sem_proc_show(struct seq_file *s, void *it)
 {
+        struct user_namespace *user_ns = seq_user_ns(s);
         struct sem_array *sma = it;
 
         return seq_printf(s,
@@ -1685,10 +1688,10 @@ static int sysvipc_sem_proc_show(struct seq_file *s, void *it)
                           sma->sem_perm.id,
                           sma->sem_perm.mode,
                           sma->sem_nsems,
-                          sma->sem_perm.uid,
-                          sma->sem_perm.gid,
-                          sma->sem_perm.cuid,
-                          sma->sem_perm.cgid,
+                          from_kuid_munged(user_ns, sma->sem_perm.uid),
+                          from_kgid_munged(user_ns, sma->sem_perm.gid),
+                          from_kuid_munged(user_ns, sma->sem_perm.cuid),
+                          from_kgid_munged(user_ns, sma->sem_perm.cgid),
                           sma->sem_otime,
                           sma->sem_ctime);
 }
diff --git a/ipc/shm.c b/ipc/shm.c
index 00faa05cf72a..dff40c9f73c9 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -758,7 +758,9 @@ static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
                 do_shm_rmid(ns, ipcp);
                 goto out_up;
         case IPC_SET:
-                ipc_update_perm(&shmid64.shm_perm, ipcp);
+                err = ipc_update_perm(&shmid64.shm_perm, ipcp);
+                if (err)
+                        goto out_unlock;
                 shp->shm_ctim = get_seconds();
                 break;
         default:
@@ -893,10 +895,10 @@ SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
                 audit_ipc_obj(&(shp->shm_perm));
 
                 if (!ns_capable(ns->user_ns, CAP_IPC_LOCK)) {
-                        uid_t euid = current_euid();
+                        kuid_t euid = current_euid();
                         err = -EPERM;
-                        if (euid != shp->shm_perm.uid &&
-                            euid != shp->shm_perm.cuid)
+                        if (!uid_eq(euid, shp->shm_perm.uid) &&
+                            !uid_eq(euid, shp->shm_perm.cuid))
                                 goto out_unlock;
                         if (cmd == SHM_LOCK && !rlimit(RLIMIT_MEMLOCK))
                                 goto out_unlock;
@@ -1220,6 +1222,7 @@ SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
 #ifdef CONFIG_PROC_FS
 static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
 {
+        struct user_namespace *user_ns = seq_user_ns(s);
         struct shmid_kernel *shp = it;
         unsigned long rss = 0, swp = 0;
 
@@ -1242,10 +1245,10 @@ static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
                           shp->shm_cprid,
                           shp->shm_lprid,
                           shp->shm_nattch,
-                          shp->shm_perm.uid,
-                          shp->shm_perm.gid,
-                          shp->shm_perm.cuid,
-                          shp->shm_perm.cgid,
+                          from_kuid_munged(user_ns, shp->shm_perm.uid),
+                          from_kgid_munged(user_ns, shp->shm_perm.gid),
+                          from_kuid_munged(user_ns, shp->shm_perm.cuid),
+                          from_kgid_munged(user_ns, shp->shm_perm.cgid),
                           shp->shm_atim,
                           shp->shm_dtim,
                           shp->shm_ctim,
diff --git a/ipc/util.c b/ipc/util.c
index eb07fd356f27..72fd0785ac94 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -249,8 +249,8 @@ int ipc_get_maxid(struct ipc_ids *ids)
  
 int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
 {
-        uid_t euid;
-        gid_t egid;
+        kuid_t euid;
+        kgid_t egid;
         int id, err;
 
         if (size > IPCMNI)
@@ -606,14 +606,14 @@ void ipc_rcu_putref(void *ptr)
  
 int ipcperms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, short flag)
 {
-        uid_t euid = current_euid();
+        kuid_t euid = current_euid();
         int requested_mode, granted_mode;
 
         audit_ipc_obj(ipcp);
         requested_mode = (flag >> 6) | (flag >> 3) | flag;
         granted_mode = ipcp->mode;
-        if (euid == ipcp->cuid ||
-            euid == ipcp->uid)
+        if (uid_eq(euid, ipcp->cuid) ||
+            uid_eq(euid, ipcp->uid))
                 granted_mode >>= 6;
         else if (in_group_p(ipcp->cgid) || in_group_p(ipcp->gid))
                 granted_mode >>= 3;
@@ -643,10 +643,10 @@ int ipcperms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, short flag)
 void kernel_to_ipc64_perm (struct kern_ipc_perm *in, struct ipc64_perm *out)
 {
         out->key        = in->key;
-        out->uid        = in->uid;
-        out->gid        = in->gid;
-        out->cuid       = in->cuid;
-        out->cgid       = in->cgid;
+        out->uid        = from_kuid_munged(current_user_ns(), in->uid);
+        out->gid        = from_kgid_munged(current_user_ns(), in->gid);
+        out->cuid       = from_kuid_munged(current_user_ns(), in->cuid);
+        out->cgid       = from_kgid_munged(current_user_ns(), in->cgid);
         out->mode       = in->mode;
         out->seq        = in->seq;
 }
@@ -747,12 +747,19 @@ int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
  * @in:  the permission given as input.
  * @out: the permission of the ipc to set.
  */
-void ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out)
+int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out)
 {
-        out->uid = in->uid;
-        out->gid = in->gid;
+        kuid_t uid = make_kuid(current_user_ns(), in->uid);
+        kgid_t gid = make_kgid(current_user_ns(), in->gid);
+        if (!uid_valid(uid) || !gid_valid(gid))
+                return -EINVAL;
+
+        out->uid = uid;
+        out->gid = gid;
         out->mode = (out->mode & ~S_IRWXUGO)
                 | (in->mode & S_IRWXUGO);
+
+        return 0;
 }
 
 /**
@@ -777,7 +784,7 @@ struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns,
                                       struct ipc64_perm *perm, int extra_perm)
 {
         struct kern_ipc_perm *ipcp;
-        uid_t euid;
+        kuid_t euid;
         int err;
 
         down_write(&ids->rw_mutex);
@@ -793,7 +800,7 @@ struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns,
                                          perm->gid, perm->mode);
 
         euid = current_euid();
-        if (euid == ipcp->cuid || euid == ipcp->uid  ||
+        if (uid_eq(euid, ipcp->cuid) || uid_eq(euid, ipcp->uid)  ||
             ns_capable(ns->user_ns, CAP_SYS_ADMIN))
                 return ipcp;
 
diff --git a/ipc/util.h b/ipc/util.h
index 850ef3e962cb..c8fe2f7631e9 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -125,7 +125,7 @@ struct kern_ipc_perm *ipc_lock(struct ipc_ids *, int);
 
 void kernel_to_ipc64_perm(struct kern_ipc_perm *in, struct ipc64_perm *out);
 void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out);
-void ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out);
+int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out);
 struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns,
                                       struct ipc_ids *ids, int id, int cmd,
                                       struct ipc64_perm *perm, int extra_perm);