https://bugs.openldap.org/show_bug.cgi?id=9842
--- Comment #1 from Howard Chu hyc@openldap.org --- (In reply to stephan.j.bircher from comment #0)
The documentation for the function mdb_cursor_put states for MDB_RESERVE the following: "return a pointer to the reserved space, which the caller can fill in later". However this seems only to be valid if no other operation is performed on the cursor. Once the cursor is moved the page where the reserved data resides on might become untracked and therefore eligible to be spilled at any time.
True. Any data pointed to by a cursor is only valid while the cursor points to it. There's no bug here.