For corrupting a block dd can be used. Just adjust the “ibs” argument to match your database block size and adjust “count” to specify the amount of blocks to be corrupted. “Seek” specifies how many blocks are skipped (counted from the beginning of the file) before writing the corrupted data.
dd ibs=8192 seek=100 count=110 if=/dev/zero of=test01.dbf conv=notrunc
Caution: This command WILL corrupt your data file. Use it ONLY on test systems and with a valid backup!