The array we kmalloc() here is not large enough.

Thanks to Johann Dahm and David Richter for bug report and testing.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Cc: David Richter <richterd@citi.umich.edu>
Tested-by: NJohann Dahm <jdahm@umich.edu>