[RFC]confusion about syscall

[Mulyadi Santosa]

Hi...

On Sun, Jul 15, 2012 at 4:18 PM, 王哲 <wangzhe5004 at gmail.com> wrote:
>    thanks for reply.
>    and i wander why the address of vsyscall page is not 0xffffe000 in my
> system?

address space randomization sometimes put the vsyscall page in much
lower address AFAIK. And it varies per invocation...

But wait, i just recall that your getpid() might contain a jump into
unpatched PLT first. It happens for the first time an external
function is called. On subsequent call, getpid() will jump directly to
the needed address in glibc.

Once I wrote about it....try google...

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
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