I would not do that. Userspace Apps have way to many ways to screw up memory managment already. Allowing them to buf=malloc(128); free(buf, 256); seem

I would not do that. Userspace Apps have way to many ways to screw up memory managment already. Allowing them to buf=malloc(128); free(buf, 256); seems dangerous, if free can't check the size. But kernels sometimes do just that ( free(ptr, size) ), for performance reasons and because "kernel writers know what they are doing".