[...]
> In theory it is possible to write executable code into a buffer
> in the data segment and overflow a buffer in the stack so that
> the stack frame contains a return address that points into that
> data. In practice it is much harder to create an exploit with
> this method as it requires quite detailed knowledge of the data
> segment layout.
Yep, it is somewhat harder, and thus not done regularly by crackers today,
as this is rarely needed now. If/when this becomes common, the cracks will
become common too. Then we are where we started. Better than buying (false)
security is to fix the affected programs.
-- Dr. Horst H. von Brand mailto:vonbrand@inf.utfsm.cl Departamento de Informatica Fono: +56 32 654431 Universidad Tecnica Federico Santa Maria +56 32 654239 Casilla 110-V, Valparaiso, Chile Fax: +56 32 797513- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/