diff --git a/libraries/liblmdb/CHANGES b/libraries/liblmdb/CHANGES
index 5bfb22ef7a..6892dde1ef 100644
--- a/libraries/liblmdb/CHANGES
+++ b/libraries/liblmdb/CHANGES
@@ -2,6 +2,7 @@ LMDB 0.9 Change Log
 
 LMDB 0.9.18 Release Engineering
 	Fix robust mutex detection on glibc 2.10-11 (ITS#8330)
+	Fix page_search_root assert on FreeDB (ITS#8336)
 	Check for utf8_to_utf16 failures (ITS#7992)
 	Catch strdup failure in mdb_dbi_open
 	Build
diff --git a/libraries/liblmdb/lmdb.h b/libraries/liblmdb/lmdb.h
index 3ecdc1063c..8323af5ec0 100644
--- a/libraries/liblmdb/lmdb.h
+++ b/libraries/liblmdb/lmdb.h
@@ -1458,7 +1458,8 @@ int  mdb_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
 	 *		the database supports duplicates (#MDB_DUPSORT).
 	 *	<li>#MDB_RESERVE - reserve space for data of the given size, but
 	 *		don't copy the given data. Instead, return a pointer to the
-	 *		reserved space, which the caller can fill in later. This saves
+	 *		reserved space, which the caller can fill in later - before
+	 *		the next update operation or the transaction ends. This saves
 	 *		an extra memcpy if the data is being generated later. This flag
 	 *		must not be specified if the database was opened with #MDB_DUPSORT.
 	 *	<li>#MDB_APPEND - append the given key/data pair to the end of the
diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index fa0c9e5b9c..a624cba3c4 100644
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -5279,7 +5279,11 @@ mdb_page_search_root(MDB_cursor *mc, MDB_val *key, int flags)
 		indx_t		i;
 
 		DPRINTF(("branch page %"Z"u has %u keys", mp->mp_pgno, NUMKEYS(mp)));
-		mdb_cassert(mc, NUMKEYS(mp) > 1);
+		/* Don't assert on branch pages in the FreeDB. We can get here
+		 * while in the process of rebalancing a FreeDB branch page; we must
+		 * let that proceed. ITS#8336
+		 */
+		mdb_cassert(mc, !mc->mc_dbi || NUMKEYS(mp) > 1);
 		DPRINTF(("found index 0 to page %"Z"u", NODEPGNO(NODEPTR(mp, 0))));
 
 		if (flags & (MDB_PS_FIRST|MDB_PS_LAST)) {