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cglibc

Is there a fast way to remove malloc/free/memalign/realloc hooks in glibc?

I've tried to patch the libc i'm using to never call malloc hook. But this hook is actually initialized with a pointer to this function:

malloc_hook_ini (size_t sz, const void *caller)
{
      __malloc_hook = NULL;
      ptmalloc_init ();
      return __libc_malloc (sz);
}

I think this function is responsible for critical initializations in malloc, so it needs to be called at least once. For instance since the free hook is not initialized with a critical function, i can just nop the call instruction

Solution

  • DJ Delorie posted a patch which removes the hooks. It requires some porting to the current tree, though.

    Alternatively, you could interpose a different malloc which does not have such hooks. If you do this, glibc will use the interposed malloc, so the hooks are never called, either.