I am running Debian 2.6.26-21lenny4 and I am puzzled by an issue with the
enforcement of page permissions. I have written a simple program with a basic
buffer overflow and compiled two versions using gcc: one with -z execstack and
another with -z noexecstack.
So, to verify that the option takes:
For the -z execstack version:
$ readelf -l a.out | grep -i -A1 stack
GNU_STACK 0x000000 0x00000000 0x00000000 0x00000 0x00000 RWE 0x4
For the -z noexecstack version:
$ readelf -l a.out | grep -i -A1 stack
GNU_STACK 0x000000 0x00000000 0x00000000 0x00000 0x00000 RW 0x4
However, I am able to inject and execute shellcode from a stack local character
buffer in both versions. Is there another system option I am unaware of that
affects enforcement? Is enforcement not supported for my system version?
Thanks for your help.
