From: Ilya Dryomov <idryomov@gmail.com>
Date: Tue, 19 Feb 2019 15:07:22 +0000 (+0100)
Subject: librados: don't claim ObjectOperation::cmpext() buffer
X-Git-Tag: v14.1.0~36^2~3
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=4daddf0564dcd548ecc7c214ab9a41fc12ba71c0;p=ceph.git

librados: don't claim ObjectOperation::cmpext() buffer

This is counter-intuitive and doesn't match the behavior of either
other compare ops (cmpxattr, omap_cmp) or write ops.

Fixes: http://tracker.ceph.com/issues/38383
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---

diff --git a/src/include/rados/librados.hpp b/src/include/rados/librados.hpp
index c4a87aa2697e..081ccb3e1c24 100644
--- a/src/include/rados/librados.hpp
+++ b/src/include/rados/librados.hpp
@@ -303,7 +303,7 @@ namespace librados
     //flag mean ObjectOperationFlags
     void set_op_flags2(int flags);
 
-    void cmpext(uint64_t off, bufferlist& cmp_bl, int *prval);
+    void cmpext(uint64_t off, const bufferlist& cmp_bl, int *prval);
     void cmpxattr(const char *name, uint8_t op, const bufferlist& val);
     void cmpxattr(const char *name, uint8_t op, uint64_t v);
     void exec(const char *cls, const char *method, bufferlist& inbl);
diff --git a/src/librados/librados_cxx.cc b/src/librados/librados_cxx.cc
index 601141670871..c174c7d58a79 100644
--- a/src/librados/librados_cxx.cc
+++ b/src/librados/librados_cxx.cc
@@ -115,11 +115,12 @@ void librados::ObjectOperation::set_op_flags2(int flags)
 }
 
 void librados::ObjectOperation::cmpext(uint64_t off,
-                                       bufferlist &cmp_bl,
+                                       const bufferlist &cmp_bl,
                                        int *prval)
 {
   ::ObjectOperation *o = &impl->o;
-  o->cmpext(off, cmp_bl, prval);
+  bufferlist c = cmp_bl;
+  o->cmpext(off, c, prval);
 }
 
 void librados::ObjectOperation::cmpxattr(const char *name, uint8_t op, const bufferlist& v)
diff --git a/src/test/librados_test_stub/LibradosTestStub.cc b/src/test/librados_test_stub/LibradosTestStub.cc
index 78a290a3ac5e..bd9a8f1860dc 100644
--- a/src/test/librados_test_stub/LibradosTestStub.cc
+++ b/src/test/librados_test_stub/LibradosTestStub.cc
@@ -811,7 +811,8 @@ size_t ObjectOperation::size() {
   return o->ops.size();
 }
 
-void ObjectOperation::cmpext(uint64_t off, bufferlist& cmp_bl, int *prval) {
+void ObjectOperation::cmpext(uint64_t off, const bufferlist& cmp_bl,
+                             int *prval) {
   TestObjectOperationImpl *o = reinterpret_cast<TestObjectOperationImpl*>(impl);
   ObjectOperationTestImpl op = boost::bind(&TestIoCtxImpl::cmpext, _1, _2, off, cmp_bl);
   if (prval != NULL) {