Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

Pull ceph fixes from Sage Weil:
 "Jim's fix closes a narrow race introduced with the msgr changes.  One
  fix resolves problems with debugfs initialization that Yan found when
  multiple client instances are created (e.g., two clusters mounted, or
  rbd + cephfs), another one fixes problems with mounting a nonexistent
  server subdirectory, and the last one fixes a divide by zero error
  from unsanitized ioctl input that Dan Carpenter found."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  ceph: avoid divide by zero in __validate_layout()
  libceph: avoid truncation due to racing banners
  ceph: tolerate (and warn on) extraneous dentry from mds
  libceph: delay debugfs initialization until we learn global_id

3 files changed, 13 insertions, 6 deletions

diff --git a/fs/ceph/debugfs.c b/fs/ceph/debugfs.c
index fb962efdace..6d59006bfa2 100644
--- a/fs/ceph/debugfs.c
+++ b/fs/ceph/debugfs.c
@@ -201,6 +201,7 @@ int ceph_fs_debugfs_init(struct ceph_fs_client *fsc)
         int err = -ENOMEM;
 
         dout("ceph_fs_debugfs_init\n");
+        BUG_ON(!fsc->client->debugfs_dir);
         fsc->debugfs_congestion_kb =
                 debugfs_create_file("writeback_congestion_kb",
                                     0600,
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 9fff9f3b17e..4b5762ef7c2 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -992,11 +992,15 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
         if (rinfo->head->is_dentry) {
                 struct inode *dir = req->r_locked_dir;
 
-                err = fill_inode(dir, &rinfo->diri, rinfo->dirfrag,
-                                 session, req->r_request_started, -1,
-                                 &req->r_caps_reservation);
-                if (err < 0)
-                        return err;
+                if (dir) {
+                        err = fill_inode(dir, &rinfo->diri, rinfo->dirfrag,
+                                         session, req->r_request_started, -1,
+                                         &req->r_caps_reservation);
+                        if (err < 0)
+                                return err;
+                } else {
+                        WARN_ON_ONCE(1);
+                }
         }
 
         /*
@@ -1004,6 +1008,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
          * will have trouble splicing in the virtual snapdir later
          */
         if (rinfo->head->is_dentry && !req->r_aborted &&
+            req->r_locked_dir &&
             (rinfo->head->is_target || strncmp(req->r_dentry->d_name.name,
                                                fsc->mount_options->snapdir_name,
                                                req->r_dentry->d_name.len))) {
diff --git a/fs/ceph/ioctl.c b/fs/ceph/ioctl.c
index 8e3fb69fbe6..1396ceb4679 100644
--- a/fs/ceph/ioctl.c
+++ b/fs/ceph/ioctl.c
@@ -42,7 +42,8 @@ static long __validate_layout(struct ceph_mds_client *mdsc,
         /* validate striping parameters */
         if ((l->object_size & ~PAGE_MASK) ||
             (l->stripe_unit & ~PAGE_MASK) ||
-            ((unsigned)l->object_size % (unsigned)l->stripe_unit))
+            (l->stripe_unit != 0 &&
+             ((unsigned)l->object_size % (unsigned)l->stripe_unit)))
                 return -EINVAL;
 
         /* make sure it's a valid data pool */