From: Matt Benjamin <mbenjamin@redhat.com>
Date: Wed, 14 Aug 2019 18:11:16 +0000 (-0400)
Subject: rgw_file: readdir: do not construct markers w/leading '/'
X-Git-Tag: v13.2.7~111^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=274d798b75079f23a6616e07cecb0b45067743d6;p=ceph.git

rgw_file: readdir: do not construct markers w/leading '/'

This case arises when listing the top directory of a bucket, and,
with proper continued enumeration, would generate a non-terminating
loop if a directory contained names which sort lexically before '/'.

Fixes: https://tracker.ceph.com/issues/41252

Signed-off-by: Matt Benjamin <mbenjamin@redhat.com>
(cherry picked from commit ca546fc53e5111052cbd7da35cb3105dde9b8bd1)
---

diff --git a/src/rgw/rgw_file.h b/src/rgw/rgw_file.h
index eade60cff8f6..1cf7fbd2cec0 100644
--- a/src/rgw/rgw_file.h
+++ b/src/rgw/rgw_file.h
@@ -486,17 +486,17 @@ namespace rgw {
 	reserve += (1 + tfh->object_name().length());
 	tfh = tfh->parent;
       }
-      bool first = true;
+      int pos = 1;
       path.reserve(reserve);
       for (auto& s : boost::adaptors::reverse(segments)) {
-	if (! first)
+	if (pos > 1) {
 	  path += "/";
-	else {
+	} else {
 	  if (!omit_bucket && (path.front() != '/')) // pretty-print
 	    path += "/";
-	  first = false;
 	}
 	path += *s;
+	++pos;
       }
       return path;
     }
@@ -1422,8 +1422,9 @@ public:
       const char* mk = get<const char*>(offset);
       if (mk) {
 	std::string tmark{rgw_fh->relative_object_name()};
-	tmark += "/";
-	tmark += mk;	
+	if (tmark.length() > 0)
+	  tmark += "/";
+	tmark += mk;
 	marker = rgw_obj_key{std::move(tmark), "", ""};
       }
     }