On 08/05/2015 05:46 PM, Leonid Yegoshin wrote:
On 08/05/2015 05:37 PM, David Daney wrote:
This just means that your userspace is broken.
If GLibC cannot do the right thing then it should be fixed.
Let's skip this until you explain how to create a fully
non-executable-stack process.
Build almost any program with a gcc/glibc from a recent Cavium SDK
toolchain.
Something like this:
mips64-octeon-linux-gnu-gcc -o myprogram myprogram.c
You cannot change the default setting for executable stack just
because you have created a broken userspace.
Please give me at least one example, one existing application which
would suffer.
Anything compiled with gcj that uses java.lang.reflect.Method.invoke()
Anything that uses gcc nested functions.
Anything that uses libffi
Where an older toolchain that doesn't set PT_GNU_STACK was used.
I remember that people already wrote here that this kind of apps (which
is based on eXecutable stack and doesn't announce it in PT_GNU_STACK)
need to be eliminated.
The ability of legacy userspace to continue functioning cannot be
sacrificed.
Not at any price.
However, this switch is a separate patch from others. It can be not
applied or it can be applied, depending from prevailing mind - what is
more significant, some (unknown) app or non-executable stack protection.
- Leonid.
