Function read_sb_page may return ERR_PTR(...). Check for it.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NeilBrown <neilb@suse.de>
                                page = bitmap->sb_page;
                                offset = sizeof(bitmap_super_t);
                                if (!file)
-                                       read_sb_page(bitmap->mddev,
-                                                    bitmap->mddev->bitmap_info.offset,
-                                                    page,
-                                                    index, count);
+                                       page = read_sb_page(
+                                               bitmap->mddev,
+                                               bitmap->mddev->bitmap_info.offset,
+                                               page,
+                                               index, count);
                        } else if (file) {
                                page = read_page(file, index, bitmap, count);
                                offset = 0;