Blocking the IP did away with repeating getblocks messages for now.
The mempool messages are still rolling in after a wallet restart and a rescan.
Same here on hbn.zabmail.ru:
getblocks -1 to 00000000000000000000 limit 500
getblocks -1 to 00000000000000000000 limit 500
ERROR: mempool transaction missing input
getblocks -1 to 00000000000000000000 limit 500
ERROR: mempool transaction missing input
Flushing wallet.dat
Flushed wallet.dat 93ms
getblocks -1 to 00000000000000000000 limit 500
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input
connection timeout
ERROR: mempool transaction missing input
trying connection 83.79.123.234:7372 lastseen=37.1hrs
connect() failed after select(): Connection refused
ERROR: mempool transaction missing input
trying connection 46.98.62.63:7372 lastseen=66.6hrs
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input
ThreadRPCServer method=getinfo
ERROR: mempool transaction missing input
ThreadRPCServer method=getmininginfo
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input
ERROR: mempool transaction missing input