From: Jason Dillaman <dillaman@redhat.com>
Date: Sun, 25 Jan 2015 18:56:02 +0000 (-0500)
Subject: cls_rbd: object_map_resize shrink protection
X-Git-Tag: v0.93~143^2~3
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=f4b9442a88b88c7a5437e8307e9b2c125308feca;p=ceph.git

cls_rbd: object_map_resize shrink protection

When shrinking an object map, object_map_resize now ensures
that the objects being removed are initialized to default
state to protect against losing track of in-use objects.

Signed-off-by: Jason Dillaman <dillaman@redhat.com>
---

diff --git a/src/cls/rbd/cls_rbd.cc b/src/cls/rbd/cls_rbd.cc
index fdd6bba2d4e..481ca31be23 100644
--- a/src/cls/rbd/cls_rbd.cc
+++ b/src/cls/rbd/cls_rbd.cc
@@ -1972,7 +1972,14 @@ int object_map_resize(cls_method_context_t hctx, bufferlist *in, bufferlist *out
   }
 
   size_t orig_object_map_size = object_map.size();
-  if (orig_object_map_size != object_count) {
+  if (object_count < orig_object_map_size) {
+    for (uint64_t i = object_count; i < orig_object_map_size; ++i) {
+      if (object_map[i] != default_state) {
+	return -ESTALE;
+      }
+    }
+    object_map.resize(object_count);
+  } else if (object_count > orig_object_map_size) {
     object_map.resize(object_count);
     for (uint64_t i = orig_object_map_size; i < object_count; ++i) {
       object_map[i] = default_state;
diff --git a/src/test/cls_rbd/test_cls_rbd.cc b/src/test/cls_rbd/test_cls_rbd.cc
index e5f52c21ca3..3642efe2f87 100644
--- a/src/test/cls_rbd/test_cls_rbd.cc
+++ b/src/test/cls_rbd/test_cls_rbd.cc
@@ -960,11 +960,16 @@ TEST_F(TestClsRbd, object_map_resize)
   ASSERT_EQ(0, object_map_load(&ioctx, oid, &osd_bit_vector));
   ASSERT_EQ(ref_bit_vector, osd_bit_vector);
 
-  ref_bit_vector.resize(16);
+  ref_bit_vector.resize(32);
 
   librados::ObjectWriteOperation op3;
   object_map_resize(&op3, ref_bit_vector.size(), 1);
-  ASSERT_EQ(0, ioctx.operate(oid, &op3));
+  ASSERT_EQ(-ESTALE, ioctx.operate(oid, &op3));
+
+  librados::ObjectWriteOperation op4;
+  object_map_resize(&op4, ref_bit_vector.size(), 2);
+  ASSERT_EQ(0, ioctx.operate(oid, &op4));
+
   ASSERT_EQ(0, object_map_load(&ioctx, oid, &osd_bit_vector));
   ASSERT_EQ(ref_bit_vector, osd_bit_vector);