The Jargon File (version 4.4.7, 29 Dec 2003):

smash the stack
 n.

    [C programming] To corrupt the execution stack by writing past the end of a
    local array or other data structure. Code that smashes the stack can cause
    a return from the routine to jump to a random address, resulting in some of
    the most insidious data-dependent bugs known to mankind. Variants include
    trash the stack, scribble the stack, mangle the stack; the term **mung
     the stack is not used, as this is never done intentionally. See spam;
    see also aliasing bug, fandango on core, memory leak, memory smash,
    precedence lossage, overrun screw.


The Free On-line Dictionary of Computing (30 December 2018):

smash the stack

    In C programming, to corrupt the execution stack by
   writing past the end of a local array or other data structure.
   Code that smashes the stack can cause a return from the
   routine to jump to a random address, resulting in insidious
   data-dependent bugs.

   Variants include "trash" the stack, scribble the stack,
   mangle the stack.

   See spam; see also aliasing bug, fandango on core,
   memory leak, memory smash, precedence lossage, overrun
   screw.

   [Jargon File]

   (1995-03-16)