From: Matt Benjamin <mbenjamin@redhat.com>
Date: Fri, 14 Jun 2019 18:26:27 +0000 (-0400)
Subject: rgw_file: fix readdir eof() calc--caller stop implies !eof
X-Git-Tag: v13.2.7~80^2~1
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=84784a2466a7916f4b71d0f8eb905a8ec3018673;p=ceph.git

rgw_file: fix readdir eof() calc--caller stop implies !eof

If rgw_readdir2()'s caller stops enumeration by returning an error
from the readdir callback function, the value of eof is false
for the rgw_readdir2() call.  I.e., eof() is true when the
underlying listing is !truncated and no results were refused by
the caller.

Fixes: http://tracker.ceph.com/issues/40375

Signed-off-by: Matt Benjamin <mbenjamin@redhat.com>
(cherry picked from commit 7fa9cf35deca5efbf82cf438574d7afe15748bc0)
---

diff --git a/src/rgw/rgw_file.h b/src/rgw/rgw_file.h
index eade60cff8f..c206acfef06 100644
--- a/src/rgw/rgw_file.h
+++ b/src/rgw/rgw_file.h
@@ -1272,12 +1272,14 @@ public:
   uint64_t* ioff;
   size_t ix;
   uint32_t d_count;
+  bool rcb_eof; // caller forced early stop in readdir cycle
 
   RGWListBucketsRequest(CephContext* _cct, RGWUserInfo *_user,
 			RGWFileHandle* _rgw_fh, rgw_readdir_cb _rcb,
 			void* _cb_arg, RGWFileHandle::readdir_offset& _offset)
     : RGWLibRequest(_cct, _user), rgw_fh(_rgw_fh), offset(_offset),
-      cb_arg(_cb_arg), rcb(_rcb), ioff(nullptr), ix(0), d_count(0) {
+      cb_arg(_cb_arg), rcb(_rcb), ioff(nullptr), ix(0), d_count(0),
+      rcb_eof(false) {
 
     using boost::get;
 
@@ -1350,6 +1352,7 @@ public:
 			      << " dirent=" << ent.bucket.name
 			      << " call count=" << ix
 			      << dendl;
+	rcb_eof = true;
 	return;
       }
       ++ix;
@@ -1383,7 +1386,7 @@ public:
 			     << " is_truncated: " << is_truncated
 			     << dendl;
     }
-    return !is_truncated;
+    return !is_truncated && !rcb_eof;
   }
 
 }; /* RGWListBucketsRequest */
@@ -1403,12 +1406,14 @@ public:
   uint64_t* ioff;
   size_t ix;
   uint32_t d_count;
+  bool rcb_eof; // caller forced early stop in readdir cycle
 
   RGWReaddirRequest(CephContext* _cct, RGWUserInfo *_user,
 		    RGWFileHandle* _rgw_fh, rgw_readdir_cb _rcb,
 		    void* _cb_arg, RGWFileHandle::readdir_offset& _offset)
     : RGWLibRequest(_cct, _user), rgw_fh(_rgw_fh), offset(_offset),
-      cb_arg(_cb_arg), rcb(_rcb), ioff(nullptr), ix(0), d_count(0) {
+      cb_arg(_cb_arg), rcb(_rcb), ioff(nullptr), ix(0), d_count(0),
+      rcb_eof(false) {
 
     using boost::get;
 
@@ -1519,12 +1524,13 @@ public:
 			     << " (" << sref << ")" << ""
 			     << dendl;
 
-      if(! this->operator()(sref, next_marker, RGW_FS_TYPE_FILE)) {
+      if (! this->operator()(sref, next_marker, RGW_FS_TYPE_FILE)) {
 	/* caller cannot accept more */
 	lsubdout(cct, rgw, 5) << "readdir rcb failed"
 			      << " dirent=" << sref.data()
 			      << " call count=" << ix
 			      << dendl;
+	rcb_eof = true;
 	return;
       }
       ++ix;
@@ -1565,7 +1571,15 @@ public:
 	return;
       }
 
-      this->operator()(sref, next_marker, RGW_FS_TYPE_DIRECTORY);
+      if (! this->operator()(sref, next_marker, RGW_FS_TYPE_DIRECTORY)) {
+	/* caller cannot accept more */
+	lsubdout(cct, rgw, 5) << "readdir rcb failed"
+			      << " dirent=" << sref.data()
+			      << " call count=" << ix
+			      << dendl;
+	rcb_eof = true;
+	return;
+      }
       ++ix;
     }
   }
@@ -1585,7 +1599,7 @@ public:
 			     << " is_truncated: " << is_truncated
 			     << dendl;
     }
-    return !is_truncated;
+    return !is_truncated && !rcb_eof;
   }
 
 }; /* RGWReaddirRequest */