From 380c61bcf725d760362317176a2ca3f4cd601c8f Mon Sep 17 00:00:00 2001
From: Howard Chu <hyc@openldap.org>
Date: Fri, 13 Nov 2015 09:25:55 +0000
Subject: [PATCH] mdbx: backport - ITS#8310 fix mdb_rebalance cursor fixup.

When collapsing root, must adjust entire cursor stack

Change-Id: If62c42f556311e785aa414954a3d7fddc077cf62
---
 CHANGES | 1 +
 mdb.c   | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/CHANGES b/CHANGES
index 3880ee12..15ea76d9 100644
--- a/CHANGES
+++ b/CHANGES
@@ -8,6 +8,7 @@ LMDB 0.9.17 Release Engineering
 	Fix ITS#8258 rebalance/split assert
 	Fix ITS#8263 cursor_put cursor tracking
 	Fix ITS#8264 cursor_del cursor tracking
+	Fix ITS#8310 cursor_del cursor tracking
 	Fix ITS#8299 mdb_del cursor tracking
 	Fix ITS#8300 mdb_del cursor tracking
 	Fix ITS#8304 mdb_del cursor tracking
diff --git a/mdb.c b/mdb.c
index 064d3d0e..afafd152 100644
--- a/mdb.c
+++ b/mdb.c
@@ -8103,9 +8103,9 @@ mdb_rebalance(MDB_cursor *mc)
 						m3 = &m2->mc_xcursor->mx_cursor;
 					else
 						m3 = m2;
-					if (m3 == mc || m3->mc_snum < mc->mc_snum) continue;
+					if (m3 == mc) continue;
 					if (m3->mc_pg[0] == mp) {
-						for (i=0; i<m3->mc_snum; i++) {
+						for (i=0; i<mc->mc_db->md_depth; i++) {
 							m3->mc_pg[i] = m3->mc_pg[i+1];
 							m3->mc_ki[i] = m3->mc_ki[i+1];
 						}